K8PetStore: A scalable kubernetes application with automated load generation (#3137).

examples/k8petstore/README.md

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+## Welcome to k8PetStore
+
+This is a follow up to the Guestbook example, which implements a slightly more real world demonstration using 
+
+the same application architecture.
+
+- It leverages the same components (redis, Go REST API) as the guestbook application
+- It comes with visualizations for graphing whats happening in Redis transactions, along with commandline printouts of transaction throughput
+- It is hackable : you can build all images from the files is in this repository (With the exception of the data generator, which is apache bigtop).
+- It generates massive load using a semantically rich, realistic transaction simulator for petstores
+
+This application will run a web server which returns REDIS records for a petstore application.
+It is meant to simulate and test high load on kubernetes or any other docker based system.
+
+If you are new to kubernetes, and you haven't run guestbook yet, 
+
+you might want to stop here and go back and run guestbook app first.  
+
+The guestbook tutorial will teach you alot about the basics of kubernetes, and we've tried not to be redundant here.
+
+## Architecture of this SOA
+
+A diagram of the overall architecture of this application can be seen in arch.dot (you can paste the contents in any graphviz viewer, including online ones such as http://sandbox.kidstrythisathome.com/erdos/.
+
+## Docker image dependencies
+
+Reading this section is optional, only if you want to rebuild everything from scratch.
+
+This project depends on three docker images which you can build for yourself and save
+in your dockerhub "dockerhub-name".
+
+Since these images are already published under other parties like redis, jayunit100, and so on,
+so you don't need to build the images to run the app. 
+
+If you do want to build the images, you will need to build and push these 3 docker images.
+
+- dockerhub-name/bigpetstore-load-generator, which generates transactions for the database.
+- dockerhub-name/redis, which is a simple curated redis image.
+- dockerhub-name/k8petstore, which is the web app image.
+
+## Get started with the WEBAPP 
+
+The web app is written in Go, and borrowed from the original Guestbook example by brendan burns.
+
+We have extended it to do some error reporting, persisting of JSON petstore transactions (not much different then guestbook entries),
+
+and supporting of additional REST calls, like LLEN, which returns the total # of transactions in the database.
+
+To run it locally, you simply need to run basic Go commands.  Assuming you have Go set up, do something like: 
+
+```
+#Assuming your gopath is in / (i.e. this is the case, for example, in our Dockerfile).
+go get main
+go build main
+export STATIC_FILES=/tmp/static
+/gopath/bin/main
+```
+
+## Set up the data generator
+
+The web front end provides users an interface for watching pet store transactions in real time as they occur.
+
+To generate those transactions, you can use the bigpetstore data generator.  Alternatively, you could just write a 
+
+shell script which calls "curl localhost:3000/k8petstore/rpush/blahblahblah" over and over again :).  But thats not nearly
+
+as fun, and its not a good test of a real world scenario where payloads scale and have lots of information content. 
+
+Similarly, you can locally run and test the data generator code, which is Java based, you can pull it down directly from 
+
+apache bigtop.
+
+Directions for that are here : https://github.com/apache/bigtop/tree/master/bigtop-bigpetstore/bigpetstore-transaction-queue
+
+You will likely want to checkout the branch 2b2392bf135e9f1256bd0b930f05ae5aef8bbdcb, which is the exact commit which the current k8petstore was tested on.
+
+## Set up REDIS
+
+Install and run redis locally.  This can be done very easily on any Unix system, and redis starts in an insecure mode so its easy 
+
+to develop against.
+
+Install the bigpetstore-transaction-queue generator app locally (optional), but for realistic testing.
+Then, run the go app directly.  You will have to get dependencies using go the first time (will add directions later for that, its easy).
+
+## Now what? 
+
+Once you have done the above 3 steps, you have a working, from source, locally runnable version of the k8petstore app, now, we can try to run it in kubernetes.
+
+## Hacking, testing, benchmarking
+
+Once the app is running, you can go to the location of publicIP:3000 (the first parameter in the script).  In your browser, you should see a chart 
+
+and the k8petstore title page, as well as an indicator of transaction throughput, and so on.  You should be able to modify  
+
+You can modify the HTML pages, add new REST paths to the Go app, and so on.
+
+## Running in kubernetes
+
+Now that you are done hacking around on the app, you can run it in kubernetes.  To do this, you will want to rebuild the docker images (most likely, for the Go web-server app), but less likely for the other images which you are less likely to need to change. Then you will push those images to dockerhub.
+
+Now, how to run the entire application in kubernetes? 
+
+To simplify running this application, we have a single file, k8petstore.sh, which writes out json files on to disk.  This allows us to have dynamic parameters, without needing to worry about managing multiplejson files.
+
+You might want to change it to point to your customized Go image, if you chose to modify things.  
+
+like the number of data generators (more generators will create more load on the redis master).
+
+So, to run this app in kubernetes, simply run `k8petstore.sh`.
+
+## Future
+
+In the future, we plan to add cassandra support.  Redis is a fabulous in memory data store, but it is not meant for truly available and resilient storage.  
+
+Thus we plan to add another tier of queueing, which empties the REDIS transactions into a cassandra store which persists.   
+
+## Questions
+
+For questions on running this app, you can ask on the google containers group.
+
+For questions about bigpetstore, and how the data is generated, ask on the apache bigtop mailing list.
+

examples/k8petstore/Vagrantfile

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+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+require 'fileutils'
+
+#$fes = 1
+#$rslavess = 1 
+
+Vagrant.configure("2") do |config|
+
+    config.vm.define "rmaster" do |rm|     
+        rm.vm.provider "docker" do |d|
+            d.vagrant_vagrantfile = "./docker-host/Vagrantfile"  
+            d.build_dir = "redis-master"
+            d.name = "rmaster"
+            d.create_args = ["--privileged=true", "-m", "1g"]
+            #d.ports = [ "6379:6379" ]
+            d.remains_running = true
+        end
+    end
+
+    config.vm.define "frontend" do |fe|
+        fe.vm.provider "docker" do |d|
+            d.vagrant_vagrantfile = "./docker-host/Vagrantfile"
+            d.build_dir = "web-server"
+            d.name = "web-server"
+            d.create_args = ["--privileged=true"]
+            d.remains_running = true
+            d.create_args = d.create_args << "--link" << "rmaster:rmaster"
+            d.ports = ["3000:3000"]
+            d.env = {"REDISMASTER_SERVICE_HOST"=>"rmaster","REDISMASTER_SERVICE_PORT"=>"6379"} 
+        end
+    end
+
+   
+ 
+    ### Todo , add data generator.
+
+
+end

examples/k8petstore/bps-data-generator/README.md

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+# How to generate the bps-data-generator container #
+
+This container is maintained as part of the apache bigtop project.
+
+To create it, simply 
+
+`git clone https://github.com/apache/bigtop`
+
+and checkout the last exact version (will be updated periodically).
+
+`git checkout -b aNewBranch 2b2392bf135e9f1256bd0b930f05ae5aef8bbdcb`
+
+then, cd to bigtop-bigpetstore/bigpetstore-transaction-queue, and run the docker file, i.e. 
+
+`Docker build -t -i jayunit100/bps-transaction-queue`.

examples/k8petstore/build-push-containers.sh

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+#K8PetStore version is tied to the redis version.  We will add more info to version tag later.
+#Change the 'jayunit100' string below to you're own dockerhub name and run this script.
+#It will build all the containers for this application and publish them to your dockerhub account
+version="r.2.8.19"
+docker build -t jayunit100/k8-petstore-redis:$version ./redis/
+docker build -t jayunit100/k8-petstore-redis-master:$version ./redis-master
+docker build -t jayunit100/k8-petstore-redis-slave:$version ./redis-slave
+docker build -t jayunit100/k8-petstore-web-server:$version ./web-server
+
+docker push jayunit100/k8-petstore-redis:$version
+docker push jayunit100/k8-petstore-redis-master:$version
+docker push jayunit100/k8-petstore-redis-slave:$version
+docker push jayunit100/k8-petstore-web-server:$version

examples/k8petstore/dev/README

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+### Local development 
+
+1) Install Go
+
+2) Install Redis
+
+Now start a local redis instance 
+
+```
+redis-server
+```
+
+And run the app 
+
+```
+export GOPATH=~/Development/k8hacking/k8petstore/web-server/
+cd $GOPATH/src/main/
+## Now, you're in the local dir to run the app.  Go get its depenedencies.
+go get
+go run PetStoreBook.go
+```
+
+Once the app works the way you want it to, test it in the vagrant recipe below.  This will gaurantee that you're local environment isn't doing something that breaks the containers at the  versioning level.
+
+### Testing 
+
+This folder can be used by anyone interested in building and developing the k8petstore application.
+
+This is for dev and test.
+
+`vagrant up` gets you a cluster with the app's core components running.
+
+You can rename Vagrantfile_atomic to Vagrantfile if you want to try to test in atomic instead.
+
+** Now you can run the code on the kubernetes cluster with reasonable assurance that any problems you run into are not bugs in the code itself :) *

examples/k8petstore/dev/Vagrantfile

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+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+require 'fileutils'
+
+#$fes = 1
+#$rslavess = 1 
+
+Vagrant.configure("2") do |config|
+
+    config.vm.define "rmaster" do |rm|     
+        rm.vm.provider "docker" do |d|
+            d.vagrant_vagrantfile = "./hosts/Vagrantfile"  
+            d.build_dir = "../redis-master"
+            d.name = "rmaster"
+            d.create_args = ["--privileged=true"]
+            #d.ports = [ "6379:6379" ]
+            d.remains_running = true
+        end
+    end
+   
+   puts "sleep 20 to make sure container is up..."
+   sleep(20)    
+   puts "resume"
+
+    config.vm.define "frontend" do |fe|
+        fe.vm.provider "docker" do |d|
+            d.vagrant_vagrantfile = "./hosts/Vagrantfile"
+            d.build_dir = "../web-server"
+            d.name = "web-server"
+            d.create_args = ["--privileged=true"]
+            d.remains_running = true
+            d.create_args = d.create_args << "--link" << "rmaster:rmaster"
+            d.ports = ["3000:3000"]
+            d.env = {"REDISMASTER_SERVICE_HOST"=>"rmaster","REDISMASTER_SERVICE_PORT"=>"6379"} 
+        end
+    end
+
+   
+ 
+    ### Todo , add data generator.
+
+
+end

examples/k8petstore/dev/hosts/Vagrantfile

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+VAGRANTFILE_API_VERSION = "2"
+
+Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
+  config.vm.box = "jayunit100/centos7"
+  config.vm.provision "docker"
+  config.vm.provision "shell", inline: "ps aux | grep 'sshd:' | awk '{print $2}' | xargs kill"
+  config.vm.provision "shell", inline: "yum install -y git && service firewalld stop && service docker restart"  
+  config.vm.provision "shell", inline: "docker ps -a | awk '{print $1}' | xargs --no-run-if-empty docker rm -f || ls"
+  config.vm.network :forwarded_port, guest: 3000, host: 3000
+
+end

examples/k8petstore/dev/test.sh

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+## First set up the host VM.  That ensures
+## we avoid vagrant race conditions.
+set -x 
+
+cd hosts/ 
+echo "note: the VM must be running before you try this"
+echo "if not already running, cd to hosts and run vagrant up"
+vagrant provision
+#echo "removing containers"
+#vagrant ssh -c "sudo docker rm -f $(docker ps -a -q)"
+cd ..
+
+## Now spin up the docker containers
+## these will run in the ^ host vm above.
+
+vagrant up
+
+## Finally, curl the length, it should be 3 .
+
+x=`curl localhost:3000/llen`
+
+for i in `seq 1 100` do
+    if [ x$x == "x3" ]; then 
+       echo " passed $3 "
+       exit 0
+    else
+       echo " FAIL" 
+    fi
+done
+
+exit 1 # if we get here the test obviously failed.

examples/k8petstore/k8petstore.dot

@@ -0,0 +1,9 @@
+ digraph k8petstore {
+          
+    USERS -> publicIP_proxy -> web_server;
+    bps_data_generator -> web_server [arrowhead = crow, label = "http://$FRONTEND_SERVICE_HOST:3000/rpush/k8petstore/{name..address..,product=..."];
+    external -> web_server [arrowhead = crow, label="  http://$FRONTEND_SERVICE_HOST/k8petstore/llen:3000"];
+    web_server -> redis_master [label=" RESP : k8petstore, llen"];
+    redis_master -> redis_slave [arrowhead = crow] [label="replication (one-way)"];
+}
+                                            

examples/k8petstore/k8petstore.sh

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+echo "WRITING KUBE FILES , will overwrite the jsons, then testing pods. is kube clean ready to go?"
+
+VERSION="r.2.8.19"
+PUBLIC_IP="127.0.0.1" # ip which we use to access the Web server.
+SECONDS=1000          # number of seconds to measure throughput.
+FE="1"                # amount of Web server  
+LG="1"                # amount of load generators
+SLAVE="1"             # amount of redis slaves 
+
+function create { 
+
+cat << EOF > fe-rc.json
+{
+  "id": "fectrl",
+  "kind": "ReplicationController",
+  "apiVersion": "v1beta1",
+  "desiredState": {
+    "replicas": $FE,
+    "replicaSelector": {"name": "frontend"},
+    "podTemplate": {
+      "desiredState": {
+         "manifest": {
+           "version": "v1beta1",
+           "id": "frontendCcontroller",
+           "containers": [{
+             "name": "frontend-go-restapi",
+             "image": "jayunit100/k8-petstore-web-server:$VERSION",
+           }]
+         }
+       },
+       "labels": {
+         "name": "frontend",
+         "uses": "redis-master"
+       }
+      }},
+  "labels": {"name": "frontend"}
+}
+EOF
+
+cat << EOF > bps-load-gen-rc.json
+{
+  "id": "bpsloadgenrc",
+  "kind": "ReplicationController",
+  "apiVersion": "v1beta1",
+  "desiredState": {
+    "replicas": $LG,
+    "replicaSelector": {"name": "bps"},
+    "podTemplate": {
+      "desiredState": {
+         "manifest": {
+           "version": "v1beta1",
+           "id": "bpsLoadGenController",
+           "containers": [{
+             "name": "bps",
+             "image": "jayunit100/bigpetstore-load-generator",
+             "command": ["sh","-c","/opt/PetStoreLoadGenerator-1.0/bin/PetStoreLoadGenerator http://\$FRONTEND_SERVICE_HOST:3000/rpush/k8petstore/ 4 4 1000 123"]
+         }]
+         }
+       },
+       "labels": {
+         "name": "bps",
+         "uses": "frontend"
+        }
+      }},
+  "labels": {"name": "bpsLoadGenController"}
+}
+EOF
+
+cat << EOF > fe-s.json
+{
+  "id": "frontend",
+  "kind": "Service",
+  "apiVersion": "v1beta1",
+  "port": 3000,
+  "containerPort": 3000,
+  "publicIPs":["$PUBLIC_IP","$PUBLIC_IP2", "10.1.4.89","127.0.0.1","10.1.4.82"],
+  "selector": {
+    "name": "frontend"
+  },
+  "labels": {
+    "name": "frontend"
+  }
+}
+EOF
+
+cat << EOF > rm.json
+{
+  "id": "redismaster",
+  "kind": "Pod",
+  "apiVersion": "v1beta1",
+  "desiredState": {
+    "manifest": {
+      "version": "v1beta1",
+      "id": "redismaster",
+      "containers": [{
+        "name": "master",
+        "image": "jayunit100/k8-petstore-redis-master:$VERSION",
+        "ports": [{
+          "containerPort": 6379,
+          "hostPort": 6379
+        }]
+      }]
+    }
+  },
+  "labels": {
+    "name": "redis-master"
+  }
+}
+EOF
+
+cat << EOF > rm-s.json
+{
+  "id": "redismaster",
+  "kind": "Service",
+  "apiVersion": "v1beta1",
+  "port": 6379,
+  "containerPort": 6379,
+  "selector": {
+    "name": "redis-master"
+  },
+  "labels": {
+    "name": "redis-master"
+  }
+}
+EOF
+
+cat << EOF > rs-s.json
+{
+  "id": "redisslave",
+  "kind": "Service",
+  "apiVersion": "v1beta1",
+  "port": 6379,
+  "containerPort": 6379,
+  "labels": {
+    "name": "redisslave"
+  },
+  "selector": {
+    "name": "redisslave"
+  }
+}
+EOF
+
+cat << EOF > slave-rc.json
+{
+  "id": "redissc",
+  "kind": "ReplicationController",
+  "apiVersion": "v1beta1",
+  "desiredState": {
+    "replicas": $SLAVE,
+    "replicaSelector": {"name": "redisslave"},
+    "podTemplate": {
+      "desiredState": {
+         "manifest": {
+           "version": "v1beta1",
+           "id": "redissc",
+           "containers": [{
+             "name": "slave",
+             "image": "jayunit100/k8-petstore-redis-slave:$VERSION",
+             "ports": [{"containerPort": 6379, "hostPort": 6380}]
+           }]
+         }
+      },
+      "labels": {
+        "name": "redisslave",
+        "uses": "redis-master"
+      }
+    }
+  },
+  "labels": {"name": "redisslave"}
+}
+EOF
+kubectl create -f rm.json --api-version=v1beta1
+kubectl create -f rm-s.json --api-version=v1beta1
+sleep 3 # precaution to prevent fe from spinning up too soon.
+kubectl create -f slave-rc.json --api-version=v1beta1
+kubectl create -f rs-s.json --api-version=v1beta1
+sleep 3 # see above comment.
+kubectl create -f fe-rc.json --api-version=v1beta1 
+kubectl create -f fe-s.json --api-version=v1beta1
+kubectl create -f bps-load-gen-rc.json --api-version=v1beta1
+}
+
+function test { 
+	pass_http=0
+
+	### Test HTTP Server comes up.
+	for i in `seq 1 150`;
+	do
+	    ### Just testing that the front end comes up.  Not sure how to test total entries etc... (yet)
+	    echo "Trying curl ... $i . expect a few failures while pulling images... " 
+	    curl "$PUBLIC_IP:3000" > result
+	    cat result
+	    cat result | grep -q "k8-bps"
+	    if [ $? -eq 0 ]; then
+		echo "TEST PASSED after $i tries !"
+		i=1000
+		break
+	    else	
+		echo "the above RESULT didn't contain target string for trial $i"
+	    fi
+	    sleep 5
+	done
+
+	if [ $i -eq 1000 ]; then
+	   pass_http=-1
+	fi
+
+	pass_load=0 
+
+	### Print statistics of db size, every second, until $SECONDS are up.
+	for i in `seq 1 $SECONDS`;
+	do
+	    echo "curl : $i"
+            curl "$PUBLIC_IP:3000/llen" >> result
+	    sleep 1
+	done
+}
+
+create
+
+test

examples/k8petstore/redis-master/Dockerfile

@@ -0,0 +1,17 @@
+#
+# Redis Dockerfile
+#
+# https://github.com/dockerfile/redis
+#
+
+# Pull base image.
+#
+# Just a stub. 
+
+FROM jayunit100/redis:2.8.19
+
+ADD etc_redis_redis.conf /etc/redis/redis.conf
+
+CMD ["redis-server", "/etc/redis/redis.conf"]
+# Expose ports.
+EXPOSE 6379

examples/k8petstore/redis-master/etc_redis_redis.conf

@@ -0,0 +1,796 @@
+# Redis configuration file example
+
+# Note on units: when memory size is needed, it is possible to specify
+# it in the usual form of 1k 5GB 4M and so forth:
+#
+# 1k => 1000 bytes
+# 1kb => 1024 bytes
+# 1m => 1000000 bytes
+# 1mb => 1024*1024 bytes
+# 1g => 1000000000 bytes
+# 1gb => 1024*1024*1024 bytes
+#
+# units are case insensitive so 1GB 1Gb 1gB are all the same.
+
+################################## INCLUDES ###################################
+
+# Include one or more other config files here.  This is useful if you
+# have a standard template that goes to all Redis server but also need
+# to customize a few per-server settings.  Include files can include
+# other files, so use this wisely.
+#
+# Notice option "include" won't be rewritten by command "CONFIG REWRITE"
+# from admin or Redis Sentinel. Since Redis always uses the last processed
+# line as value of a configuration directive, you'd better put includes
+# at the beginning of this file to avoid overwriting config change at runtime.
+#
+# If instead you are interested in using includes to override configuration
+# options, it is better to use include as the last line.
+#
+# include /path/to/local.conf
+# include /path/to/other.conf
+
+################################ GENERAL  #####################################
+
+# By default Redis does not run as a daemon. Use 'yes' if you need it.
+# Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
+# daemonize no
+
+# When running daemonized, Redis writes a pid file in /var/run/redis.pid by
+# default. You can specify a custom pid file location here.
+pidfile /var/run/redis.pid
+
+# Accept connections on the specified port, default is 6379.
+# If port 0 is specified Redis will not listen on a TCP socket.
+port 6379
+
+# TCP listen() backlog.
+#
+# In high requests-per-second environments you need an high backlog in order
+# to avoid slow clients connections issues. Note that the Linux kernel
+# will silently truncate it to the value of /proc/sys/net/core/somaxconn so
+# make sure to raise both the value of somaxconn and tcp_max_syn_backlog
+# in order to get the desired effect.
+tcp-backlog 511
+
+# By default Redis listens for connections from all the network interfaces
+# available on the server. It is possible to listen to just one or multiple
+# interfaces using the "bind" configuration directive, followed by one or
+# more IP addresses.
+#
+# Examples:
+#
+# bind 192.168.1.100 10.0.0.1
+# bind 127.0.0.1
+
+# Specify the path for the Unix socket that will be used to listen for
+# incoming connections. There is no default, so Redis will not listen
+# on a unix socket when not specified.
+#
+# unixsocket /tmp/redis.sock
+# unixsocketperm 700
+
+# Close the connection after a client is idle for N seconds (0 to disable)
+timeout 0
+
+# TCP keepalive.
+#
+# If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
+# of communication. This is useful for two reasons:
+#
+# 1) Detect dead peers.
+# 2) Take the connection alive from the point of view of network
+#    equipment in the middle.
+#
+# On Linux, the specified value (in seconds) is the period used to send ACKs.
+# Note that to close the connection the double of the time is needed.
+# On other kernels the period depends on the kernel configuration.
+#
+# A reasonable value for this option is 60 seconds.
+tcp-keepalive 0
+
+# Specify the server verbosity level.
+# This can be one of:
+# debug (a lot of information, useful for development/testing)
+# verbose (many rarely useful info, but not a mess like the debug level)
+# notice (moderately verbose, what you want in production probably)
+# warning (only very important / critical messages are logged)
+loglevel verbose
+
+# Specify the log file name. Also the empty string can be used to force
+# Redis to log on the standard output. Note that if you use standard
+# output for logging but daemonize, logs will be sent to /dev/null
+# logfile ""
+
+# To enable logging to the system logger, just set 'syslog-enabled' to yes,
+# and optionally update the other syslog parameters to suit your needs.
+syslog-enabled yes
+
+# Specify the syslog identity.
+# syslog-ident redis
+
+# Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
+# syslog-facility local0
+
+# Set the number of databases. The default database is DB 0, you can select
+# a different one on a per-connection basis using SELECT <dbid> where
+# dbid is a number between 0 and 'databases'-1
+databases 16
+
+################################ SNAPSHOTTING  ################################
+#
+# Save the DB on disk:
+#
+#   save <seconds> <changes>
+#
+#   Will save the DB if both the given number of seconds and the given
+#   number of write operations against the DB occurred.
+#
+#   In the example below the behaviour will be to save:
+#   after 900 sec (15 min) if at least 1 key changed
+#   after 300 sec (5 min) if at least 10 keys changed
+#   after 60 sec if at least 10000 keys changed
+#
+#   Note: you can disable saving at all commenting all the "save" lines.
+#
+#   It is also possible to remove all the previously configured save
+#   points by adding a save directive with a single empty string argument
+#   like in the following example:
+#
+#   save ""
+
+### Modification for extreme consistency, experimenal (jay)
+save 1 1
+save 900 1
+save 300 10
+save 60 10000
+
+# By default Redis will stop accepting writes if RDB snapshots are enabled
+# (at least one save point) and the latest background save failed.
+# This will make the user aware (in a hard way) that data is not persisting
+# on disk properly, otherwise chances are that no one will notice and some
+# disaster will happen.
+#
+# If the background saving process will start working again Redis will
+# automatically allow writes again.
+#
+# However if you have setup your proper monitoring of the Redis server
+# and persistence, you may want to disable this feature so that Redis will
+# continue to work as usual even if there are problems with disk,
+# permissions, and so forth.
+stop-writes-on-bgsave-error yes
+
+# Compress string objects using LZF when dump .rdb databases?
+# For default that's set to 'yes' as it's almost always a win.
+# If you want to save some CPU in the saving child set it to 'no' but
+# the dataset will likely be bigger if you have compressible values or keys.
+rdbcompression no
+
+# Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
+# This makes the format more resistant to corruption but there is a performance
+# hit to pay (around 10%) when saving and loading RDB files, so you can disable it
+# for maximum performances.
+#
+# RDB files created with checksum disabled have a checksum of zero that will
+# tell the loading code to skip the check.
+rdbchecksum yes
+
+# The filename where to dump the DB
+dbfilename dump.rdb
+
+# The working directory.
+#
+# The DB will be written inside this directory, with the filename specified
+# above using the 'dbfilename' configuration directive.
+# 
+# The Append Only File will also be created inside this directory.
+# 
+# Note that you must specify a directory here, not a file name.
+# dir ./
+
+# should we toggle this, try a persistent dir w/ iscsi?
+dir /data
+
+################################# REPLICATION #################################
+
+# Master-Slave replication. Use slaveof to make a Redis instance a copy of
+# another Redis server. A few things to understand ASAP about Redis replication.
+#
+# 1) Redis replication is asynchronous, but you can configure a master to
+#    stop accepting writes if it appears to be not connected with at least
+#    a given number of slaves.
+# 2) Redis slaves are able to perform a partial resynchronization with the
+#    master if the replication link is lost for a relatively small amount of
+#    time. You may want to configure the replication backlog size (see the next
+#    sections of this file) with a sensible value depending on your needs.
+# 3) Replication is automatic and does not need user intervention. After a
+#    network partition slaves automatically try to reconnect to masters
+#    and resynchronize with them.
+#
+# slaveof <masterip> <masterport>
+
+# If the master is password protected (using the "requirepass" configuration
+# directive below) it is possible to tell the slave to authenticate before
+# starting the replication synchronization process, otherwise the master will
+# refuse the slave request.
+#
+# masterauth <master-password>
+
+# When a slave loses its connection with the master, or when the replication
+# is still in progress, the slave can act in two different ways:
+#
+# 1) if slave-serve-stale-data is set to 'yes' (the default) the slave will
+#    still reply to client requests, possibly with out of date data, or the
+#    data set may just be empty if this is the first synchronization.
+#
+# 2) if slave-serve-stale-data is set to 'no' the slave will reply with
+#    an error "SYNC with master in progress" to all the kind of commands
+#    but to INFO and SLAVEOF.
+#
+
+# experimental change to "no"  hopefully this will highlight when there are failures 
+# at the consistency level (jay)
+slave-serve-stale-data no
+
+# You can configure a slave instance to accept writes or not. Writing against
+# a slave instance may be useful to store some ephemeral data (because data
+# written on a slave will be easily deleted after resync with the master) but
+# may also cause problems if clients are writing to it because of a
+# misconfiguration.
+#
+# Since Redis 2.6 by default slaves are read-only.
+#
+# Note: read only slaves are not designed to be exposed to untrusted clients
+# on the internet. It's just a protection layer against misuse of the instance.
+# Still a read only slave exports by default all the administrative commands
+# such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
+# security of read only slaves using 'rename-command' to shadow all the
+# administrative / dangerous commands.
+slave-read-only yes
+
+# Slaves send PINGs to server in a predefined interval. It's possible to change
+# this interval with the repl_ping_slave_period option. The default value is 10
+# seconds.
+#
+# repl-ping-slave-period 10
+
+# The following option sets the replication timeout for:
+#
+# 1) Bulk transfer I/O during SYNC, from the point of view of slave.
+# 2) Master timeout from the point of view of slaves (data, pings).
+# 3) Slave timeout from the point of view of masters (REPLCONF ACK pings).
+#
+# It is important to make sure that this value is greater than the value
+# specified for repl-ping-slave-period otherwise a timeout will be detected
+# every time there is low traffic between the master and the slave.
+#
+# repl-timeout 60
+
+# Disable TCP_NODELAY on the slave socket after SYNC?
+#
+# If you select "yes" Redis will use a smaller number of TCP packets and
+# less bandwidth to send data to slaves. But this can add a delay for
+# the data to appear on the slave side, up to 40 milliseconds with
+# Linux kernels using a default configuration.
+#
+# If you select "no" the delay for data to appear on the slave side will
+# be reduced but more bandwidth will be used for replication.
+#
+# By default we optimize for low latency, but in very high traffic conditions
+# or when the master and slaves are many hops away, turning this to "yes" may
+# be a good idea.
+repl-disable-tcp-nodelay no
+
+# Set the replication backlog size. The backlog is a buffer that accumulates
+# slave data when slaves are disconnected for some time, so that when a slave
+# wants to reconnect again, often a full resync is not needed, but a partial
+# resync is enough, just passing the portion of data the slave missed while
+# disconnected.
+#
+# The biggest the replication backlog, the longer the time the slave can be
+# disconnected and later be able to perform a partial resynchronization.
+#
+# The backlog is only allocated once there is at least a slave connected.
+#
+# repl-backlog-size 1mb
+
+# After a master has no longer connected slaves for some time, the backlog
+# will be freed. The following option configures the amount of seconds that
+# need to elapse, starting from the time the last slave disconnected, for
+# the backlog buffer to be freed.
+#
+# A value of 0 means to never release the backlog.
+#
+# repl-backlog-ttl 3600
+
+# The slave priority is an integer number published by Redis in the INFO output.
+# It is used by Redis Sentinel in order to select a slave to promote into a
+# master if the master is no longer working correctly.
+#
+# A slave with a low priority number is considered better for promotion, so
+# for instance if there are three slaves with priority 10, 100, 25 Sentinel will
+# pick the one with priority 10, that is the lowest.
+#
+# However a special priority of 0 marks the slave as not able to perform the
+# role of master, so a slave with priority of 0 will never be selected by
+# Redis Sentinel for promotion.
+#
+# By default the priority is 100.
+slave-priority 100
+
+# It is possible for a master to stop accepting writes if there are less than
+# N slaves connected, having a lag less or equal than M seconds.
+#
+# The N slaves need to be in "online" state.
+#
+# The lag in seconds, that must be <= the specified value, is calculated from
+# the last ping received from the slave, that is usually sent every second.
+#
+# This option does not GUARANTEES that N replicas will accept the write, but
+# will limit the window of exposure for lost writes in case not enough slaves
+# are available, to the specified number of seconds.
+#
+# For example to require at least 3 slaves with a lag <= 10 seconds use:
+#
+# min-slaves-to-write 3
+# min-slaves-max-lag 10
+#
+# Setting one or the other to 0 disables the feature.
+#
+# By default min-slaves-to-write is set to 0 (feature disabled) and
+# min-slaves-max-lag is set to 10.
+
+################################## SECURITY ###################################
+
+# Require clients to issue AUTH <PASSWORD> before processing any other
+# commands.  This might be useful in environments in which you do not trust
+# others with access to the host running redis-server.
+#
+# This should stay commented out for backward compatibility and because most
+# people do not need auth (e.g. they run their own servers).
+# 
+# Warning: since Redis is pretty fast an outside user can try up to
+# 150k passwords per second against a good box. This means that you should
+# use a very strong password otherwise it will be very easy to break.
+#
+# requirepass foobared
+
+# Command renaming.
+#
+# It is possible to change the name of dangerous commands in a shared
+# environment. For instance the CONFIG command may be renamed into something
+# hard to guess so that it will still be available for internal-use tools
+# but not available for general clients.
+#
+# Example:
+#
+# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
+#
+# It is also possible to completely kill a command by renaming it into
+# an empty string:
+#
+# rename-command CONFIG ""
+#
+# Please note that changing the name of commands that are logged into the
+# AOF file or transmitted to slaves may cause problems.
+
+################################### LIMITS ####################################
+
+# Set the max number of connected clients at the same time. By default
+# this limit is set to 10000 clients, however if the Redis server is not
+# able to configure the process file limit to allow for the specified limit
+# the max number of allowed clients is set to the current file limit
+# minus 32 (as Redis reserves a few file descriptors for internal uses).
+#
+# Once the limit is reached Redis will close all the new connections sending
+# an error 'max number of clients reached'.
+#
+# maxclients 10000
+
+# Don't use more memory than the specified amount of bytes.
+# When the memory limit is reached Redis will try to remove keys
+# according to the eviction policy selected (see maxmemory-policy).
+#
+# If Redis can't remove keys according to the policy, or if the policy is
+# set to 'noeviction', Redis will start to reply with errors to commands
+# that would use more memory, like SET, LPUSH, and so on, and will continue
+# to reply to read-only commands like GET.
+#
+# This option is usually useful when using Redis as an LRU cache, or to set
+# a hard memory limit for an instance (using the 'noeviction' policy).
+#
+# WARNING: If you have slaves attached to an instance with maxmemory on,
+# the size of the output buffers needed to feed the slaves are subtracted
+# from the used memory count, so that network problems / resyncs will
+# not trigger a loop where keys are evicted, and in turn the output
+# buffer of slaves is full with DELs of keys evicted triggering the deletion
+# of more keys, and so forth until the database is completely emptied.
+#
+# In short... if you have slaves attached it is suggested that you set a lower
+# limit for maxmemory so that there is some free RAM on the system for slave
+# output buffers (but this is not needed if the policy is 'noeviction').
+#
+# maxmemory <bytes>
+
+# MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
+# is reached. You can select among five behaviors:
+# 
+# volatile-lru -> remove the key with an expire set using an LRU algorithm
+# allkeys-lru -> remove any key accordingly to the LRU algorithm
+# volatile-random -> remove a random key with an expire set
+# allkeys-random -> remove a random key, any key
+# volatile-ttl -> remove the key with the nearest expire time (minor TTL)
+# noeviction -> don't expire at all, just return an error on write operations
+# 
+# Note: with any of the above policies, Redis will return an error on write
+#       operations, when there are not suitable keys for eviction.
+#
+#       At the date of writing this commands are: set setnx setex append
+#       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
+#       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
+#       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
+#       getset mset msetnx exec sort
+#
+# The default is:
+#
+# maxmemory-policy volatile-lru
+
+# LRU and minimal TTL algorithms are not precise algorithms but approximated
+# algorithms (in order to save memory), so you can select as well the sample
+# size to check. For instance for default Redis will check three keys and
+# pick the one that was used less recently, you can change the sample size
+# using the following configuration directive.
+#
+# maxmemory-samples 3
+
+############################## APPEND ONLY MODE ###############################
+
+# By default Redis asynchronously dumps the dataset on disk. This mode is
+# good enough in many applications, but an issue with the Redis process or
+# a power outage may result into a few minutes of writes lost (depending on
+# the configured save points).
+#
+# The Append Only File is an alternative persistence mode that provides
+# much better durability. For instance using the default data fsync policy
+# (see later in the config file) Redis can lose just one second of writes in a
+# dramatic event like a server power outage, or a single write if something
+# wrong with the Redis process itself happens, but the operating system is
+# still running correctly.
+#
+# AOF and RDB persistence can be enabled at the same time without problems.
+# If the AOF is enabled on startup Redis will load the AOF, that is the file
+# with the better durability guarantees.
+#
+# Please check http://redis.io/topics/persistence for more information.
+
+appendonly yes
+
+# The name of the append only file (default: "appendonly.aof")
+
+appendfilename "appendonly.aof"
+
+# The fsync() call tells the Operating System to actually write data on disk
+# instead to wait for more data in the output buffer. Some OS will really flush 
+# data on disk, some other OS will just try to do it ASAP.
+#
+# Redis supports three different modes:
+#
+# no: don't fsync, just let the OS flush the data when it wants. Faster.
+# always: fsync after every write to the append only log . Slow, Safest.
+# everysec: fsync only one time every second. Compromise.
+#
+# The default is "everysec", as that's usually the right compromise between
+# speed and data safety. It's up to you to understand if you can relax this to
+# "no" that will let the operating system flush the output buffer when
+# it wants, for better performances (but if you can live with the idea of
+# some data loss consider the default persistence mode that's snapshotting),
+# or on the contrary, use "always" that's very slow but a bit safer than
+# everysec.
+#
+# More details please check the following article:
+# http://antirez.com/post/redis-persistence-demystified.html
+#
+# If unsure, use "everysec".
+
+# appendfsync always
+appendfsync everysec
+# appendfsync no
+
+# When the AOF fsync policy is set to always or everysec, and a background
+# saving process (a background save or AOF log background rewriting) is
+# performing a lot of I/O against the disk, in some Linux configurations
+# Redis may block too long on the fsync() call. Note that there is no fix for
+# this currently, as even performing fsync in a different thread will block
+# our synchronous write(2) call.
+#
+# In order to mitigate this problem it's possible to use the following option
+# that will prevent fsync() from being called in the main process while a
+# BGSAVE or BGREWRITEAOF is in progress.
+#
+# This means that while another child is saving, the durability of Redis is
+# the same as "appendfsync none". In practical terms, this means that it is
+# possible to lose up to 30 seconds of log in the worst scenario (with the
+# default Linux settings).
+# 
+# If you have latency problems turn this to "yes". Otherwise leave it as
+# "no" that is the safest pick from the point of view of durability.
+
+no-appendfsync-on-rewrite no
+
+# Automatic rewrite of the append only file.
+# Redis is able to automatically rewrite the log file implicitly calling
+# BGREWRITEAOF when the AOF log size grows by the specified percentage.
+# 
+# This is how it works: Redis remembers the size of the AOF file after the
+# latest rewrite (if no rewrite has happened since the restart, the size of
+# the AOF at startup is used).
+#
+# This base size is compared to the current size. If the current size is
+# bigger than the specified percentage, the rewrite is triggered. Also
+# you need to specify a minimal size for the AOF file to be rewritten, this
+# is useful to avoid rewriting the AOF file even if the percentage increase
+# is reached but it is still pretty small.
+#
+# Specify a percentage of zero in order to disable the automatic AOF
+# rewrite feature.
+
+auto-aof-rewrite-percentage 100
+
+# another experimental feature
+auto-aof-rewrite-min-size 1 
+
+# An AOF file may be found to be truncated at the end during the Redis
+# startup process, when the AOF data gets loaded back into memory.
+# This may happen when the system where Redis is running
+# crashes, especially when an ext4 filesystem is mounted without the
+# data=ordered option (however this can't happen when Redis itself
+# crashes or aborts but the operating system still works correctly).
+#
+# Redis can either exit with an error when this happens, or load as much
+# data as possible (the default now) and start if the AOF file is found
+# to be truncated at the end. The following option controls this behavior.
+#
+# If aof-load-truncated is set to yes, a truncated AOF file is loaded and
+# the Redis server starts emitting a log to inform the user of the event.
+# Otherwise if the option is set to no, the server aborts with an error
+# and refuses to start. When the option is set to no, the user requires
+# to fix the AOF file using the "redis-check-aof" utility before to restart
+# the server.
+#
+# Note that if the AOF file will be found to be corrupted in the middle
+# the server will still exit with an error. This option only applies when
+# Redis will try to read more data from the AOF file but not enough bytes
+# will be found.
+aof-load-truncated yes
+
+################################ LUA SCRIPTING  ###############################
+
+# Max execution time of a Lua script in milliseconds.
+#
+# If the maximum execution time is reached Redis will log that a script is
+# still in execution after the maximum allowed time and will start to
+# reply to queries with an error.
+#
+# When a long running script exceed the maximum execution time only the
+# SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
+# used to stop a script that did not yet called write commands. The second
+# is the only way to shut down the server in the case a write commands was
+# already issue by the script but the user don't want to wait for the natural
+# termination of the script.
+#
+# Set it to 0 or a negative value for unlimited execution without warnings.
+lua-time-limit 5000
+
+################################## SLOW LOG ###################################
+
+# The Redis Slow Log is a system to log queries that exceeded a specified
+# execution time. The execution time does not include the I/O operations
+# like talking with the client, sending the reply and so forth,
+# but just the time needed to actually execute the command (this is the only
+# stage of command execution where the thread is blocked and can not serve
+# other requests in the meantime).
+# 
+# You can configure the slow log with two parameters: one tells Redis
+# what is the execution time, in microseconds, to exceed in order for the
+# command to get logged, and the other parameter is the length of the
+# slow log. When a new command is logged the oldest one is removed from the
+# queue of logged commands.
+
+# The following time is expressed in microseconds, so 1000000 is equivalent
+# to one second. Note that a negative number disables the slow log, while
+# a value of zero forces the logging of every command.
+slowlog-log-slower-than 10000
+
+# There is no limit to this length. Just be aware that it will consume memory.
+# You can reclaim memory used by the slow log with SLOWLOG RESET.
+slowlog-max-len 128
+
+################################ LATENCY MONITOR ##############################
+
+# The Redis latency monitoring subsystem samples different operations
+# at runtime in order to collect data related to possible sources of
+# latency of a Redis instance.
+#
+# Via the LATENCY command this information is available to the user that can
+# print graphs and obtain reports.
+#
+# The system only logs operations that were performed in a time equal or
+# greater than the amount of milliseconds specified via the
+# latency-monitor-threshold configuration directive. When its value is set
+# to zero, the latency monitor is turned off.
+#
+# By default latency monitoring is disabled since it is mostly not needed
+# if you don't have latency issues, and collecting data has a performance
+# impact, that while very small, can be measured under big load. Latency
+# monitoring can easily be enalbed at runtime using the command
+# "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
+latency-monitor-threshold 0
+
+############################# Event notification ##############################
+
+# Redis can notify Pub/Sub clients about events happening in the key space.
+# This feature is documented at http://redis.io/topics/notifications
+# 
+# For instance if keyspace events notification is enabled, and a client
+# performs a DEL operation on key "foo" stored in the Database 0, two
+# messages will be published via Pub/Sub:
+#
+# PUBLISH __keyspace@0__:foo del
+# PUBLISH __keyevent@0__:del foo
+#
+# It is possible to select the events that Redis will notify among a set
+# of classes. Every class is identified by a single character:
+#
+#  K     Keyspace events, published with __keyspace@<db>__ prefix.
+#  E     Keyevent events, published with __keyevent@<db>__ prefix.
+#  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
+#  $     String commands
+#  l     List commands
+#  s     Set commands
+#  h     Hash commands
+#  z     Sorted set commands
+#  x     Expired events (events generated every time a key expires)
+#  e     Evicted events (events generated when a key is evicted for maxmemory)
+#  A     Alias for g$lshzxe, so that the "AKE" string means all the events.
+#
+#  The "notify-keyspace-events" takes as argument a string that is composed
+#  by zero or multiple characters. The empty string means that notifications
+#  are disabled at all.
+#
+#  Example: to enable list and generic events, from the point of view of the
+#           event name, use:
+#
+#  notify-keyspace-events Elg
+#
+#  Example 2: to get the stream of the expired keys subscribing to channel
+#             name __keyevent@0__:expired use:
+#
+#  notify-keyspace-events Ex
+#
+#  By default all notifications are disabled because most users don't need
+#  this feature and the feature has some overhead. Note that if you don't
+#  specify at least one of K or E, no events will be delivered.
+notify-keyspace-events KElg
+# lots of logging, also experimental
+
+############################### ADVANCED CONFIG ###############################
+
+# Hashes are encoded using a memory efficient data structure when they have a
+# small number of entries, and the biggest entry does not exceed a given
+# threshold. These thresholds can be configured using the following directives.
+hash-max-ziplist-entries 512
+hash-max-ziplist-value 64
+
+# Similarly to hashes, small lists are also encoded in a special way in order
+# to save a lot of space. The special representation is only used when
+# you are under the following limits:
+list-max-ziplist-entries 512
+list-max-ziplist-value 64
+
+# Sets have a special encoding in just one case: when a set is composed
+# of just strings that happens to be integers in radix 10 in the range
+# of 64 bit signed integers.
+# The following configuration setting sets the limit in the size of the
+# set in order to use this special memory saving encoding.
+set-max-intset-entries 512
+
+# Similarly to hashes and lists, sorted sets are also specially encoded in
+# order to save a lot of space. This encoding is only used when the length and
+# elements of a sorted set are below the following limits:
+zset-max-ziplist-entries 128
+zset-max-ziplist-value 64
+
+# HyperLogLog sparse representation bytes limit. The limit includes the
+# 16 bytes header. When an HyperLogLog using the sparse representation crosses
+# this limit, it is converted into the dense representation.
+#
+# A value greater than 16000 is totally useless, since at that point the
+# dense representation is more memory efficient.
+# 
+# The suggested value is ~ 3000 in order to have the benefits of
+# the space efficient encoding without slowing down too much PFADD,
+# which is O(N) with the sparse encoding. The value can be raised to
+# ~ 10000 when CPU is not a concern, but space is, and the data set is
+# composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
+hll-sparse-max-bytes 3000
+
+# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
+# order to help rehashing the main Redis hash table (the one mapping top-level
+# keys to values). The hash table implementation Redis uses (see dict.c)
+# performs a lazy rehashing: the more operation you run into a hash table
+# that is rehashing, the more rehashing "steps" are performed, so if the
+# server is idle the rehashing is never complete and some more memory is used
+# by the hash table.
+# 
+# The default is to use this millisecond 10 times every second in order to
+# active rehashing the main dictionaries, freeing memory when possible.
+#
+# If unsure:
+# use "activerehashing no" if you have hard latency requirements and it is
+# not a good thing in your environment that Redis can reply form time to time
+# to queries with 2 milliseconds delay.
+#
+# use "activerehashing yes" if you don't have such hard requirements but
+# want to free memory asap when possible.
+activerehashing yes
+
+# The client output buffer limits can be used to force disconnection of clients
+# that are not reading data from the server fast enough for some reason (a
+# common reason is that a Pub/Sub client can't consume messages as fast as the
+# publisher can produce them).
+#
+# The limit can be set differently for the three different classes of clients:
+#
+# normal -> normal clients including MONITOR clients
+# slave  -> slave clients
+# pubsub -> clients subscribed to at least one pubsub channel or pattern
+#
+# The syntax of every client-output-buffer-limit directive is the following:
+#
+# client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
+#
+# A client is immediately disconnected once the hard limit is reached, or if
+# the soft limit is reached and remains reached for the specified number of
+# seconds (continuously).
+# So for instance if the hard limit is 32 megabytes and the soft limit is
+# 16 megabytes / 10 seconds, the client will get disconnected immediately
+# if the size of the output buffers reach 32 megabytes, but will also get
+# disconnected if the client reaches 16 megabytes and continuously overcomes
+# the limit for 10 seconds.
+#
+# By default normal clients are not limited because they don't receive data
+# without asking (in a push way), but just after a request, so only
+# asynchronous clients may create a scenario where data is requested faster
+# than it can read.
+#
+# Instead there is a default limit for pubsub and slave clients, since
+# subscribers and slaves receive data in a push fashion.
+#
+# Both the hard or the soft limit can be disabled by setting them to zero.
+client-output-buffer-limit normal 0 0 0
+client-output-buffer-limit slave 256mb 64mb 60
+client-output-buffer-limit pubsub 32mb 8mb 60
+
+# Redis calls an internal function to perform many background tasks, like
+# closing connections of clients in timeout, purging expired keys that are
+# never requested, and so forth.
+#
+# Not all tasks are performed with the same frequency, but Redis checks for
+# tasks to perform accordingly to the specified "hz" value.
+#
+# By default "hz" is set to 10. Raising the value will use more CPU when
+# Redis is idle, but at the same time will make Redis more responsive when
+# there are many keys expiring at the same time, and timeouts may be
+# handled with more precision.
+#
+# The range is between 1 and 500, however a value over 100 is usually not
+# a good idea. Most users should use the default of 10 and raise this up to
+# 100 only in environments where very low latency is required.
+hz 10
+
+# When a child rewrites the AOF file, if the following option is enabled
+# the file will be fsync-ed every 32 MB of data generated. This is useful
+# in order to commit the file to the disk more incrementally and avoid
+# big latency spikes.
+aof-rewrite-incremental-fsync yes
+

examples/k8petstore/redis-slave/Dockerfile

@@ -0,0 +1,15 @@
+#
+# Redis Dockerfile
+#
+# https://github.com/dockerfile/redis
+#
+
+# Pull base image.
+#
+# Just a stub. 
+
+FROM jayunit100/redis:2.8.19
+
+ADD run.sh /run.sh
+
+CMD /run.sh

examples/k8petstore/redis-slave/etc_redis_redis.conf

@@ -0,0 +1,796 @@
+# Redis configuration file example
+
+# Note on units: when memory size is needed, it is possible to specify
+# it in the usual form of 1k 5GB 4M and so forth:
+#
+# 1k => 1000 bytes
+# 1kb => 1024 bytes
+# 1m => 1000000 bytes
+# 1mb => 1024*1024 bytes
+# 1g => 1000000000 bytes
+# 1gb => 1024*1024*1024 bytes
+#
+# units are case insensitive so 1GB 1Gb 1gB are all the same.
+
+################################## INCLUDES ###################################
+
+# Include one or more other config files here.  This is useful if you
+# have a standard template that goes to all Redis server but also need
+# to customize a few per-server settings.  Include files can include
+# other files, so use this wisely.
+#
+# Notice option "include" won't be rewritten by command "CONFIG REWRITE"
+# from admin or Redis Sentinel. Since Redis always uses the last processed
+# line as value of a configuration directive, you'd better put includes
+# at the beginning of this file to avoid overwriting config change at runtime.
+#
+# If instead you are interested in using includes to override configuration
+# options, it is better to use include as the last line.
+#
+# include /path/to/local.conf
+# include /path/to/other.conf
+
+################################ GENERAL  #####################################
+
+# By default Redis does not run as a daemon. Use 'yes' if you need it.
+# Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
+# daemonize no
+
+# When running daemonized, Redis writes a pid file in /var/run/redis.pid by
+# default. You can specify a custom pid file location here.
+pidfile /var/run/redis.pid
+
+# Accept connections on the specified port, default is 6379.
+# If port 0 is specified Redis will not listen on a TCP socket.
+port 6379
+
+# TCP listen() backlog.
+#
+# In high requests-per-second environments you need an high backlog in order
+# to avoid slow clients connections issues. Note that the Linux kernel
+# will silently truncate it to the value of /proc/sys/net/core/somaxconn so
+# make sure to raise both the value of somaxconn and tcp_max_syn_backlog
+# in order to get the desired effect.
+tcp-backlog 511
+
+# By default Redis listens for connections from all the network interfaces
+# available on the server. It is possible to listen to just one or multiple
+# interfaces using the "bind" configuration directive, followed by one or
+# more IP addresses.
+#
+# Examples:
+#
+# bind 192.168.1.100 10.0.0.1
+# bind 127.0.0.1
+
+# Specify the path for the Unix socket that will be used to listen for
+# incoming connections. There is no default, so Redis will not listen
+# on a unix socket when not specified.
+#
+# unixsocket /tmp/redis.sock
+# unixsocketperm 700
+
+# Close the connection after a client is idle for N seconds (0 to disable)
+timeout 0
+
+# TCP keepalive.
+#
+# If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
+# of communication. This is useful for two reasons:
+#
+# 1) Detect dead peers.
+# 2) Take the connection alive from the point of view of network
+#    equipment in the middle.
+#
+# On Linux, the specified value (in seconds) is the period used to send ACKs.
+# Note that to close the connection the double of the time is needed.
+# On other kernels the period depends on the kernel configuration.
+#
+# A reasonable value for this option is 60 seconds.
+tcp-keepalive 0
+
+# Specify the server verbosity level.
+# This can be one of:
+# debug (a lot of information, useful for development/testing)
+# verbose (many rarely useful info, but not a mess like the debug level)
+# notice (moderately verbose, what you want in production probably)
+# warning (only very important / critical messages are logged)
+loglevel verbose
+
+# Specify the log file name. Also the empty string can be used to force
+# Redis to log on the standard output. Note that if you use standard
+# output for logging but daemonize, logs will be sent to /dev/null
+# logfile ""
+
+# To enable logging to the system logger, just set 'syslog-enabled' to yes,
+# and optionally update the other syslog parameters to suit your needs.
+syslog-enabled yes
+
+# Specify the syslog identity.
+# syslog-ident redis
+
+# Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
+# syslog-facility local0
+
+# Set the number of databases. The default database is DB 0, you can select
+# a different one on a per-connection basis using SELECT <dbid> where
+# dbid is a number between 0 and 'databases'-1
+databases 16
+
+################################ SNAPSHOTTING  ################################
+#
+# Save the DB on disk:
+#
+#   save <seconds> <changes>
+#
+#   Will save the DB if both the given number of seconds and the given
+#   number of write operations against the DB occurred.
+#
+#   In the example below the behaviour will be to save:
+#   after 900 sec (15 min) if at least 1 key changed
+#   after 300 sec (5 min) if at least 10 keys changed
+#   after 60 sec if at least 10000 keys changed
+#
+#   Note: you can disable saving at all commenting all the "save" lines.
+#
+#   It is also possible to remove all the previously configured save
+#   points by adding a save directive with a single empty string argument
+#   like in the following example:
+#
+#   save ""
+
+### Modification for extreme consistency, experimenal (jay)
+save 1 1
+save 900 1
+save 300 10
+save 60 10000
+
+# By default Redis will stop accepting writes if RDB snapshots are enabled
+# (at least one save point) and the latest background save failed.
+# This will make the user aware (in a hard way) that data is not persisting
+# on disk properly, otherwise chances are that no one will notice and some
+# disaster will happen.
+#
+# If the background saving process will start working again Redis will
+# automatically allow writes again.
+#
+# However if you have setup your proper monitoring of the Redis server
+# and persistence, you may want to disable this feature so that Redis will
+# continue to work as usual even if there are problems with disk,
+# permissions, and so forth.
+stop-writes-on-bgsave-error yes
+
+# Compress string objects using LZF when dump .rdb databases?
+# For default that's set to 'yes' as it's almost always a win.
+# If you want to save some CPU in the saving child set it to 'no' but
+# the dataset will likely be bigger if you have compressible values or keys.
+rdbcompression no
+
+# Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
+# This makes the format more resistant to corruption but there is a performance
+# hit to pay (around 10%) when saving and loading RDB files, so you can disable it
+# for maximum performances.
+#
+# RDB files created with checksum disabled have a checksum of zero that will
+# tell the loading code to skip the check.
+rdbchecksum yes
+
+# The filename where to dump the DB
+dbfilename dump.rdb
+
+# The working directory.
+#
+# The DB will be written inside this directory, with the filename specified
+# above using the 'dbfilename' configuration directive.
+# 
+# The Append Only File will also be created inside this directory.
+# 
+# Note that you must specify a directory here, not a file name.
+# dir ./
+
+# should we toggle this, try a persistent dir w/ iscsi?
+dir /data
+
+################################# REPLICATION #################################
+
+# Master-Slave replication. Use slaveof to make a Redis instance a copy of
+# another Redis server. A few things to understand ASAP about Redis replication.
+#
+# 1) Redis replication is asynchronous, but you can configure a master to
+#    stop accepting writes if it appears to be not connected with at least
+#    a given number of slaves.
+# 2) Redis slaves are able to perform a partial resynchronization with the
+#    master if the replication link is lost for a relatively small amount of
+#    time. You may want to configure the replication backlog size (see the next
+#    sections of this file) with a sensible value depending on your needs.
+# 3) Replication is automatic and does not need user intervention. After a
+#    network partition slaves automatically try to reconnect to masters
+#    and resynchronize with them.
+#
+# slaveof <masterip> <masterport>
+
+# If the master is password protected (using the "requirepass" configuration
+# directive below) it is possible to tell the slave to authenticate before
+# starting the replication synchronization process, otherwise the master will
+# refuse the slave request.
+#
+# masterauth <master-password>
+
+# When a slave loses its connection with the master, or when the replication
+# is still in progress, the slave can act in two different ways:
+#
+# 1) if slave-serve-stale-data is set to 'yes' (the default) the slave will
+#    still reply to client requests, possibly with out of date data, or the
+#    data set may just be empty if this is the first synchronization.
+#
+# 2) if slave-serve-stale-data is set to 'no' the slave will reply with
+#    an error "SYNC with master in progress" to all the kind of commands
+#    but to INFO and SLAVEOF.
+#
+
+# experimental change to "no"  hopefully this will highlight when there are failures 
+# at the consistency level (jay)
+slave-serve-stale-data no
+
+# You can configure a slave instance to accept writes or not. Writing against
+# a slave instance may be useful to store some ephemeral data (because data
+# written on a slave will be easily deleted after resync with the master) but
+# may also cause problems if clients are writing to it because of a
+# misconfiguration.
+#
+# Since Redis 2.6 by default slaves are read-only.
+#
+# Note: read only slaves are not designed to be exposed to untrusted clients
+# on the internet. It's just a protection layer against misuse of the instance.
+# Still a read only slave exports by default all the administrative commands
+# such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
+# security of read only slaves using 'rename-command' to shadow all the
+# administrative / dangerous commands.
+slave-read-only yes
+
+# Slaves send PINGs to server in a predefined interval. It's possible to change
+# this interval with the repl_ping_slave_period option. The default value is 10
+# seconds.
+#
+# repl-ping-slave-period 10
+
+# The following option sets the replication timeout for:
+#
+# 1) Bulk transfer I/O during SYNC, from the point of view of slave.
+# 2) Master timeout from the point of view of slaves (data, pings).
+# 3) Slave timeout from the point of view of masters (REPLCONF ACK pings).
+#
+# It is important to make sure that this value is greater than the value
+# specified for repl-ping-slave-period otherwise a timeout will be detected
+# every time there is low traffic between the master and the slave.
+#
+# repl-timeout 60
+
+# Disable TCP_NODELAY on the slave socket after SYNC?
+#
+# If you select "yes" Redis will use a smaller number of TCP packets and
+# less bandwidth to send data to slaves. But this can add a delay for
+# the data to appear on the slave side, up to 40 milliseconds with
+# Linux kernels using a default configuration.
+#
+# If you select "no" the delay for data to appear on the slave side will
+# be reduced but more bandwidth will be used for replication.
+#
+# By default we optimize for low latency, but in very high traffic conditions
+# or when the master and slaves are many hops away, turning this to "yes" may
+# be a good idea.
+repl-disable-tcp-nodelay no
+
+# Set the replication backlog size. The backlog is a buffer that accumulates
+# slave data when slaves are disconnected for some time, so that when a slave
+# wants to reconnect again, often a full resync is not needed, but a partial
+# resync is enough, just passing the portion of data the slave missed while
+# disconnected.
+#
+# The biggest the replication backlog, the longer the time the slave can be
+# disconnected and later be able to perform a partial resynchronization.
+#
+# The backlog is only allocated once there is at least a slave connected.
+#
+# repl-backlog-size 1mb
+
+# After a master has no longer connected slaves for some time, the backlog
+# will be freed. The following option configures the amount of seconds that
+# need to elapse, starting from the time the last slave disconnected, for
+# the backlog buffer to be freed.
+#
+# A value of 0 means to never release the backlog.
+#
+# repl-backlog-ttl 3600
+
+# The slave priority is an integer number published by Redis in the INFO output.
+# It is used by Redis Sentinel in order to select a slave to promote into a
+# master if the master is no longer working correctly.
+#
+# A slave with a low priority number is considered better for promotion, so
+# for instance if there are three slaves with priority 10, 100, 25 Sentinel will
+# pick the one with priority 10, that is the lowest.
+#
+# However a special priority of 0 marks the slave as not able to perform the
+# role of master, so a slave with priority of 0 will never be selected by
+# Redis Sentinel for promotion.
+#
+# By default the priority is 100.
+slave-priority 100
+
+# It is possible for a master to stop accepting writes if there are less than
+# N slaves connected, having a lag less or equal than M seconds.
+#
+# The N slaves need to be in "online" state.
+#
+# The lag in seconds, that must be <= the specified value, is calculated from
+# the last ping received from the slave, that is usually sent every second.
+#
+# This option does not GUARANTEES that N replicas will accept the write, but
+# will limit the window of exposure for lost writes in case not enough slaves
+# are available, to the specified number of seconds.
+#
+# For example to require at least 3 slaves with a lag <= 10 seconds use:
+#
+# min-slaves-to-write 3
+# min-slaves-max-lag 10
+#
+# Setting one or the other to 0 disables the feature.
+#
+# By default min-slaves-to-write is set to 0 (feature disabled) and
+# min-slaves-max-lag is set to 10.
+
+################################## SECURITY ###################################
+
+# Require clients to issue AUTH <PASSWORD> before processing any other
+# commands.  This might be useful in environments in which you do not trust
+# others with access to the host running redis-server.
+#
+# This should stay commented out for backward compatibility and because most
+# people do not need auth (e.g. they run their own servers).
+# 
+# Warning: since Redis is pretty fast an outside user can try up to
+# 150k passwords per second against a good box. This means that you should
+# use a very strong password otherwise it will be very easy to break.
+#
+# requirepass foobared
+
+# Command renaming.
+#
+# It is possible to change the name of dangerous commands in a shared
+# environment. For instance the CONFIG command may be renamed into something
+# hard to guess so that it will still be available for internal-use tools
+# but not available for general clients.
+#
+# Example:
+#
+# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
+#
+# It is also possible to completely kill a command by renaming it into
+# an empty string:
+#
+# rename-command CONFIG ""
+#
+# Please note that changing the name of commands that are logged into the
+# AOF file or transmitted to slaves may cause problems.
+
+################################### LIMITS ####################################
+
+# Set the max number of connected clients at the same time. By default
+# this limit is set to 10000 clients, however if the Redis server is not
+# able to configure the process file limit to allow for the specified limit
+# the max number of allowed clients is set to the current file limit
+# minus 32 (as Redis reserves a few file descriptors for internal uses).
+#
+# Once the limit is reached Redis will close all the new connections sending
+# an error 'max number of clients reached'.
+#
+# maxclients 10000
+
+# Don't use more memory than the specified amount of bytes.
+# When the memory limit is reached Redis will try to remove keys
+# according to the eviction policy selected (see maxmemory-policy).
+#
+# If Redis can't remove keys according to the policy, or if the policy is
+# set to 'noeviction', Redis will start to reply with errors to commands
+# that would use more memory, like SET, LPUSH, and so on, and will continue
+# to reply to read-only commands like GET.
+#
+# This option is usually useful when using Redis as an LRU cache, or to set
+# a hard memory limit for an instance (using the 'noeviction' policy).
+#
+# WARNING: If you have slaves attached to an instance with maxmemory on,
+# the size of the output buffers needed to feed the slaves are subtracted
+# from the used memory count, so that network problems / resyncs will
+# not trigger a loop where keys are evicted, and in turn the output
+# buffer of slaves is full with DELs of keys evicted triggering the deletion
+# of more keys, and so forth until the database is completely emptied.
+#
+# In short... if you have slaves attached it is suggested that you set a lower
+# limit for maxmemory so that there is some free RAM on the system for slave
+# output buffers (but this is not needed if the policy is 'noeviction').
+#
+# maxmemory <bytes>
+
+# MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
+# is reached. You can select among five behaviors:
+# 
+# volatile-lru -> remove the key with an expire set using an LRU algorithm
+# allkeys-lru -> remove any key accordingly to the LRU algorithm
+# volatile-random -> remove a random key with an expire set
+# allkeys-random -> remove a random key, any key
+# volatile-ttl -> remove the key with the nearest expire time (minor TTL)
+# noeviction -> don't expire at all, just return an error on write operations
+# 
+# Note: with any of the above policies, Redis will return an error on write
+#       operations, when there are not suitable keys for eviction.
+#
+#       At the date of writing this commands are: set setnx setex append
+#       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
+#       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
+#       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
+#       getset mset msetnx exec sort
+#
+# The default is:
+#
+# maxmemory-policy volatile-lru
+
+# LRU and minimal TTL algorithms are not precise algorithms but approximated
+# algorithms (in order to save memory), so you can select as well the sample
+# size to check. For instance for default Redis will check three keys and
+# pick the one that was used less recently, you can change the sample size
+# using the following configuration directive.
+#
+# maxmemory-samples 3
+
+############################## APPEND ONLY MODE ###############################
+
+# By default Redis asynchronously dumps the dataset on disk. This mode is
+# good enough in many applications, but an issue with the Redis process or
+# a power outage may result into a few minutes of writes lost (depending on
+# the configured save points).
+#
+# The Append Only File is an alternative persistence mode that provides
+# much better durability. For instance using the default data fsync policy
+# (see later in the config file) Redis can lose just one second of writes in a
+# dramatic event like a server power outage, or a single write if something
+# wrong with the Redis process itself happens, but the operating system is
+# still running correctly.
+#
+# AOF and RDB persistence can be enabled at the same time without problems.
+# If the AOF is enabled on startup Redis will load the AOF, that is the file
+# with the better durability guarantees.
+#
+# Please check http://redis.io/topics/persistence for more information.
+
+appendonly yes
+
+# The name of the append only file (default: "appendonly.aof")
+
+appendfilename "appendonly.aof"
+
+# The fsync() call tells the Operating System to actually write data on disk
+# instead to wait for more data in the output buffer. Some OS will really flush 
+# data on disk, some other OS will just try to do it ASAP.
+#
+# Redis supports three different modes:
+#
+# no: don't fsync, just let the OS flush the data when it wants. Faster.
+# always: fsync after every write to the append only log . Slow, Safest.
+# everysec: fsync only one time every second. Compromise.
+#
+# The default is "everysec", as that's usually the right compromise between
+# speed and data safety. It's up to you to understand if you can relax this to
+# "no" that will let the operating system flush the output buffer when
+# it wants, for better performances (but if you can live with the idea of
+# some data loss consider the default persistence mode that's snapshotting),
+# or on the contrary, use "always" that's very slow but a bit safer than
+# everysec.
+#
+# More details please check the following article:
+# http://antirez.com/post/redis-persistence-demystified.html
+#
+# If unsure, use "everysec".
+
+# appendfsync always
+appendfsync everysec
+# appendfsync no
+
+# When the AOF fsync policy is set to always or everysec, and a background
+# saving process (a background save or AOF log background rewriting) is
+# performing a lot of I/O against the disk, in some Linux configurations
+# Redis may block too long on the fsync() call. Note that there is no fix for
+# this currently, as even performing fsync in a different thread will block
+# our synchronous write(2) call.
+#
+# In order to mitigate this problem it's possible to use the following option
+# that will prevent fsync() from being called in the main process while a
+# BGSAVE or BGREWRITEAOF is in progress.
+#
+# This means that while another child is saving, the durability of Redis is
+# the same as "appendfsync none". In practical terms, this means that it is
+# possible to lose up to 30 seconds of log in the worst scenario (with the
+# default Linux settings).
+# 
+# If you have latency problems turn this to "yes". Otherwise leave it as
+# "no" that is the safest pick from the point of view of durability.
+
+no-appendfsync-on-rewrite no
+
+# Automatic rewrite of the append only file.
+# Redis is able to automatically rewrite the log file implicitly calling
+# BGREWRITEAOF when the AOF log size grows by the specified percentage.
+# 
+# This is how it works: Redis remembers the size of the AOF file after the
+# latest rewrite (if no rewrite has happened since the restart, the size of
+# the AOF at startup is used).
+#
+# This base size is compared to the current size. If the current size is
+# bigger than the specified percentage, the rewrite is triggered. Also
+# you need to specify a minimal size for the AOF file to be rewritten, this
+# is useful to avoid rewriting the AOF file even if the percentage increase
+# is reached but it is still pretty small.
+#
+# Specify a percentage of zero in order to disable the automatic AOF
+# rewrite feature.
+
+auto-aof-rewrite-percentage 100
+
+# another experimental feature
+auto-aof-rewrite-min-size 1 
+
+# An AOF file may be found to be truncated at the end during the Redis
+# startup process, when the AOF data gets loaded back into memory.
+# This may happen when the system where Redis is running
+# crashes, especially when an ext4 filesystem is mounted without the
+# data=ordered option (however this can't happen when Redis itself
+# crashes or aborts but the operating system still works correctly).
+#
+# Redis can either exit with an error when this happens, or load as much
+# data as possible (the default now) and start if the AOF file is found
+# to be truncated at the end. The following option controls this behavior.
+#
+# If aof-load-truncated is set to yes, a truncated AOF file is loaded and
+# the Redis server starts emitting a log to inform the user of the event.
+# Otherwise if the option is set to no, the server aborts with an error
+# and refuses to start. When the option is set to no, the user requires
+# to fix the AOF file using the "redis-check-aof" utility before to restart
+# the server.
+#
+# Note that if the AOF file will be found to be corrupted in the middle
+# the server will still exit with an error. This option only applies when
+# Redis will try to read more data from the AOF file but not enough bytes
+# will be found.
+aof-load-truncated yes
+
+################################ LUA SCRIPTING  ###############################
+
+# Max execution time of a Lua script in milliseconds.
+#
+# If the maximum execution time is reached Redis will log that a script is
+# still in execution after the maximum allowed time and will start to
+# reply to queries with an error.
+#
+# When a long running script exceed the maximum execution time only the
+# SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
+# used to stop a script that did not yet called write commands. The second
+# is the only way to shut down the server in the case a write commands was
+# already issue by the script but the user don't want to wait for the natural
+# termination of the script.
+#
+# Set it to 0 or a negative value for unlimited execution without warnings.
+lua-time-limit 5000
+
+################################## SLOW LOG ###################################
+
+# The Redis Slow Log is a system to log queries that exceeded a specified
+# execution time. The execution time does not include the I/O operations
+# like talking with the client, sending the reply and so forth,
+# but just the time needed to actually execute the command (this is the only
+# stage of command execution where the thread is blocked and can not serve
+# other requests in the meantime).
+# 
+# You can configure the slow log with two parameters: one tells Redis
+# what is the execution time, in microseconds, to exceed in order for the
+# command to get logged, and the other parameter is the length of the
+# slow log. When a new command is logged the oldest one is removed from the
+# queue of logged commands.
+
+# The following time is expressed in microseconds, so 1000000 is equivalent
+# to one second. Note that a negative number disables the slow log, while
+# a value of zero forces the logging of every command.
+slowlog-log-slower-than 10000
+
+# There is no limit to this length. Just be aware that it will consume memory.
+# You can reclaim memory used by the slow log with SLOWLOG RESET.
+slowlog-max-len 128
+
+################################ LATENCY MONITOR ##############################
+
+# The Redis latency monitoring subsystem samples different operations
+# at runtime in order to collect data related to possible sources of
+# latency of a Redis instance.
+#
+# Via the LATENCY command this information is available to the user that can
+# print graphs and obtain reports.
+#
+# The system only logs operations that were performed in a time equal or
+# greater than the amount of milliseconds specified via the
+# latency-monitor-threshold configuration directive. When its value is set
+# to zero, the latency monitor is turned off.
+#
+# By default latency monitoring is disabled since it is mostly not needed
+# if you don't have latency issues, and collecting data has a performance
+# impact, that while very small, can be measured under big load. Latency
+# monitoring can easily be enalbed at runtime using the command
+# "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
+latency-monitor-threshold 0
+
+############################# Event notification ##############################
+
+# Redis can notify Pub/Sub clients about events happening in the key space.
+# This feature is documented at http://redis.io/topics/notifications
+# 
+# For instance if keyspace events notification is enabled, and a client
+# performs a DEL operation on key "foo" stored in the Database 0, two
+# messages will be published via Pub/Sub:
+#
+# PUBLISH __keyspace@0__:foo del
+# PUBLISH __keyevent@0__:del foo
+#
+# It is possible to select the events that Redis will notify among a set
+# of classes. Every class is identified by a single character:
+#
+#  K     Keyspace events, published with __keyspace@<db>__ prefix.
+#  E     Keyevent events, published with __keyevent@<db>__ prefix.
+#  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
+#  $     String commands
+#  l     List commands
+#  s     Set commands
+#  h     Hash commands
+#  z     Sorted set commands
+#  x     Expired events (events generated every time a key expires)
+#  e     Evicted events (events generated when a key is evicted for maxmemory)
+#  A     Alias for g$lshzxe, so that the "AKE" string means all the events.
+#
+#  The "notify-keyspace-events" takes as argument a string that is composed
+#  by zero or multiple characters. The empty string means that notifications
+#  are disabled at all.
+#
+#  Example: to enable list and generic events, from the point of view of the
+#           event name, use:
+#
+#  notify-keyspace-events Elg
+#
+#  Example 2: to get the stream of the expired keys subscribing to channel
+#             name __keyevent@0__:expired use:
+#
+#  notify-keyspace-events Ex
+#
+#  By default all notifications are disabled because most users don't need
+#  this feature and the feature has some overhead. Note that if you don't
+#  specify at least one of K or E, no events will be delivered.
+notify-keyspace-events KElg
+# lots of logging, also experimental
+
+############################### ADVANCED CONFIG ###############################
+
+# Hashes are encoded using a memory efficient data structure when they have a
+# small number of entries, and the biggest entry does not exceed a given
+# threshold. These thresholds can be configured using the following directives.
+hash-max-ziplist-entries 512
+hash-max-ziplist-value 64
+
+# Similarly to hashes, small lists are also encoded in a special way in order
+# to save a lot of space. The special representation is only used when
+# you are under the following limits:
+list-max-ziplist-entries 512
+list-max-ziplist-value 64
+
+# Sets have a special encoding in just one case: when a set is composed
+# of just strings that happens to be integers in radix 10 in the range
+# of 64 bit signed integers.
+# The following configuration setting sets the limit in the size of the
+# set in order to use this special memory saving encoding.
+set-max-intset-entries 512
+
+# Similarly to hashes and lists, sorted sets are also specially encoded in
+# order to save a lot of space. This encoding is only used when the length and
+# elements of a sorted set are below the following limits:
+zset-max-ziplist-entries 128
+zset-max-ziplist-value 64
+
+# HyperLogLog sparse representation bytes limit. The limit includes the
+# 16 bytes header. When an HyperLogLog using the sparse representation crosses
+# this limit, it is converted into the dense representation.
+#
+# A value greater than 16000 is totally useless, since at that point the
+# dense representation is more memory efficient.
+# 
+# The suggested value is ~ 3000 in order to have the benefits of
+# the space efficient encoding without slowing down too much PFADD,
+# which is O(N) with the sparse encoding. The value can be raised to
+# ~ 10000 when CPU is not a concern, but space is, and the data set is
+# composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
+hll-sparse-max-bytes 3000
+
+# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
+# order to help rehashing the main Redis hash table (the one mapping top-level
+# keys to values). The hash table implementation Redis uses (see dict.c)
+# performs a lazy rehashing: the more operation you run into a hash table
+# that is rehashing, the more rehashing "steps" are performed, so if the
+# server is idle the rehashing is never complete and some more memory is used
+# by the hash table.
+# 
+# The default is to use this millisecond 10 times every second in order to
+# active rehashing the main dictionaries, freeing memory when possible.
+#
+# If unsure:
+# use "activerehashing no" if you have hard latency requirements and it is
+# not a good thing in your environment that Redis can reply form time to time
+# to queries with 2 milliseconds delay.
+#
+# use "activerehashing yes" if you don't have such hard requirements but
+# want to free memory asap when possible.
+activerehashing yes
+
+# The client output buffer limits can be used to force disconnection of clients
+# that are not reading data from the server fast enough for some reason (a
+# common reason is that a Pub/Sub client can't consume messages as fast as the
+# publisher can produce them).
+#
+# The limit can be set differently for the three different classes of clients:
+#
+# normal -> normal clients including MONITOR clients
+# slave  -> slave clients
+# pubsub -> clients subscribed to at least one pubsub channel or pattern
+#
+# The syntax of every client-output-buffer-limit directive is the following:
+#
+# client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
+#
+# A client is immediately disconnected once the hard limit is reached, or if
+# the soft limit is reached and remains reached for the specified number of
+# seconds (continuously).
+# So for instance if the hard limit is 32 megabytes and the soft limit is
+# 16 megabytes / 10 seconds, the client will get disconnected immediately
+# if the size of the output buffers reach 32 megabytes, but will also get
+# disconnected if the client reaches 16 megabytes and continuously overcomes
+# the limit for 10 seconds.
+#
+# By default normal clients are not limited because they don't receive data
+# without asking (in a push way), but just after a request, so only
+# asynchronous clients may create a scenario where data is requested faster
+# than it can read.
+#
+# Instead there is a default limit for pubsub and slave clients, since
+# subscribers and slaves receive data in a push fashion.
+#
+# Both the hard or the soft limit can be disabled by setting them to zero.
+client-output-buffer-limit normal 0 0 0
+client-output-buffer-limit slave 256mb 64mb 60
+client-output-buffer-limit pubsub 32mb 8mb 60
+
+# Redis calls an internal function to perform many background tasks, like
+# closing connections of clients in timeout, purging expired keys that are
+# never requested, and so forth.
+#
+# Not all tasks are performed with the same frequency, but Redis checks for
+# tasks to perform accordingly to the specified "hz" value.
+#
+# By default "hz" is set to 10. Raising the value will use more CPU when
+# Redis is idle, but at the same time will make Redis more responsive when
+# there are many keys expiring at the same time, and timeouts may be
+# handled with more precision.
+#
+# The range is between 1 and 500, however a value over 100 is usually not
+# a good idea. Most users should use the default of 10 and raise this up to
+# 100 only in environments where very low latency is required.
+hz 10
+
+# When a child rewrites the AOF file, if the following option is enabled
+# the file will be fsync-ed every 32 MB of data generated. This is useful
+# in order to commit the file to the disk more incrementally and avoid
+# big latency spikes.
+aof-rewrite-incremental-fsync yes
+

examples/k8petstore/redis-slave/run.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+i
+echo "Note, if you get errors below indicate kubernetes env injection could be faliing..."
+echo "env vars ="
+env
+echo "CHECKING ENVS BEFORE STARTUP........"
+if [ ! "$REDISMASTER_SERVICE_HOST" ]; then
+    echo "Need to set REDIS_MASTER_SERVICE_HOST" && exit 1;
+fi
+if [ ! "$REDISMASTER_PORT" ]; then
+    echo "Need to set REDIS_MASTER_PORT" && exit 1;
+fi
+
+echo "ENV Vars look good, starting !"
+
+redis-server --slaveof ${REDISMASTER_SERVICE_HOST:-$SERVICE_HOST} $REDISMASTER_SERVICE_PORT

examples/k8petstore/redis/Dockerfile

@@ -0,0 +1,45 @@
+#
+# Redis Dockerfile
+#
+# https://github.com/dockerfile/redis
+#
+
+# Pull base image.
+FROM dockerfile/ubuntu
+
+# Install Redis.
+RUN \
+  cd /tmp && \
+  # Modify to stay at this version rather then always update.
+
+  #################################################################
+  ###################### REDIS INSTALL ############################
+  wget http://download.redis.io/releases/redis-2.8.19.tar.gz && \
+  tar xvzf redis-2.8.19.tar.gz && \
+  cd redis-2.8.19 && \
+  ################################################################
+  ################################################################
+  make && \
+  make install && \
+  cp -f src/redis-sentinel /usr/local/bin && \
+  mkdir -p /etc/redis && \
+  cp -f *.conf /etc/redis && \
+  rm -rf /tmp/redis-stable* && \
+  sed -i 's/^\(bind .*\)$/# \1/' /etc/redis/redis.conf && \
+  sed -i 's/^\(daemonize .*\)$/# \1/' /etc/redis/redis.conf && \
+  sed -i 's/^\(dir .*\)$/# \1\ndir \/data/' /etc/redis/redis.conf && \
+  sed -i 's/^\(logfile .*\)$/# \1/' /etc/redis/redis.conf
+
+# Define mountable directories.
+VOLUME ["/data"]
+
+# Define working directory.
+WORKDIR /data
+
+ADD etc_redis_redis.conf /etc/redis/redis.conf
+
+# Print redis configs and start.
+# CMD "redis-server /etc/redis/redis.conf"
+
+# Expose ports.
+EXPOSE 6379

examples/k8petstore/redis/etc_redis_redis.conf

@@ -0,0 +1,796 @@
+# Redis configuration file example
+
+# Note on units: when memory size is needed, it is possible to specify
+# it in the usual form of 1k 5GB 4M and so forth:
+#
+# 1k => 1000 bytes
+# 1kb => 1024 bytes
+# 1m => 1000000 bytes
+# 1mb => 1024*1024 bytes
+# 1g => 1000000000 bytes
+# 1gb => 1024*1024*1024 bytes
+#
+# units are case insensitive so 1GB 1Gb 1gB are all the same.
+
+################################## INCLUDES ###################################
+
+# Include one or more other config files here.  This is useful if you
+# have a standard template that goes to all Redis server but also need
+# to customize a few per-server settings.  Include files can include
+# other files, so use this wisely.
+#
+# Notice option "include" won't be rewritten by command "CONFIG REWRITE"
+# from admin or Redis Sentinel. Since Redis always uses the last processed
+# line as value of a configuration directive, you'd better put includes
+# at the beginning of this file to avoid overwriting config change at runtime.
+#
+# If instead you are interested in using includes to override configuration
+# options, it is better to use include as the last line.
+#
+# include /path/to/local.conf
+# include /path/to/other.conf
+
+################################ GENERAL  #####################################
+
+# By default Redis does not run as a daemon. Use 'yes' if you need it.
+# Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
+# daemonize no
+
+# When running daemonized, Redis writes a pid file in /var/run/redis.pid by
+# default. You can specify a custom pid file location here.
+pidfile /var/run/redis.pid
+
+# Accept connections on the specified port, default is 6379.
+# If port 0 is specified Redis will not listen on a TCP socket.
+port 6379
+
+# TCP listen() backlog.
+#
+# In high requests-per-second environments you need an high backlog in order
+# to avoid slow clients connections issues. Note that the Linux kernel
+# will silently truncate it to the value of /proc/sys/net/core/somaxconn so
+# make sure to raise both the value of somaxconn and tcp_max_syn_backlog
+# in order to get the desired effect.
+tcp-backlog 511
+
+# By default Redis listens for connections from all the network interfaces
+# available on the server. It is possible to listen to just one or multiple
+# interfaces using the "bind" configuration directive, followed by one or
+# more IP addresses.
+#
+# Examples:
+#
+# bind 192.168.1.100 10.0.0.1
+# bind 127.0.0.1
+
+# Specify the path for the Unix socket that will be used to listen for
+# incoming connections. There is no default, so Redis will not listen
+# on a unix socket when not specified.
+#
+# unixsocket /tmp/redis.sock
+# unixsocketperm 700
+
+# Close the connection after a client is idle for N seconds (0 to disable)
+timeout 0
+
+# TCP keepalive.
+#
+# If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
+# of communication. This is useful for two reasons:
+#
+# 1) Detect dead peers.
+# 2) Take the connection alive from the point of view of network
+#    equipment in the middle.
+#
+# On Linux, the specified value (in seconds) is the period used to send ACKs.
+# Note that to close the connection the double of the time is needed.
+# On other kernels the period depends on the kernel configuration.
+#
+# A reasonable value for this option is 60 seconds.
+tcp-keepalive 0
+
+# Specify the server verbosity level.
+# This can be one of:
+# debug (a lot of information, useful for development/testing)
+# verbose (many rarely useful info, but not a mess like the debug level)
+# notice (moderately verbose, what you want in production probably)
+# warning (only very important / critical messages are logged)
+loglevel verbose
+
+# Specify the log file name. Also the empty string can be used to force
+# Redis to log on the standard output. Note that if you use standard
+# output for logging but daemonize, logs will be sent to /dev/null
+# logfile ""
+
+# To enable logging to the system logger, just set 'syslog-enabled' to yes,
+# and optionally update the other syslog parameters to suit your needs.
+syslog-enabled yes
+
+# Specify the syslog identity.
+# syslog-ident redis
+
+# Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
+# syslog-facility local0
+
+# Set the number of databases. The default database is DB 0, you can select
+# a different one on a per-connection basis using SELECT <dbid> where
+# dbid is a number between 0 and 'databases'-1
+
+databases 1 ### This is for an app that only does 1 thing.
+
+################################ SNAPSHOTTING  ################################
+#
+# Save the DB on disk:
+#
+#   save <seconds> <changes>
+#
+#   Will save the DB if both the given number of seconds and the given
+#   number of write operations against the DB occurred.
+#
+#   In the example below the behaviour will be to save:
+#   after 900 sec (15 min) if at least 1 key changed
+#   after 300 sec (5 min) if at least 10 keys changed
+#   after 60 sec if at least 10000 keys changed
+#
+#   Note: you can disable saving at all commenting all the "save" lines.
+#
+#   It is also possible to remove all the previously configured save
+#   points by adding a save directive with a single empty string argument
+#   like in the following example:
+#
+#   save ""
+
+### Modification for extreme consistency, experimenal (jay)
+save 1 1
+save 900 1
+save 300 10
+save 60 10000
+
+# By default Redis will stop accepting writes if RDB snapshots are enabled
+# (at least one save point) and the latest background save failed.
+# This will make the user aware (in a hard way) that data is not persisting
+# on disk properly, otherwise chances are that no one will notice and some
+# disaster will happen.
+#
+# If the background saving process will start working again Redis will
+# automatically allow writes again.
+#
+# However if you have setup your proper monitoring of the Redis server
+# and persistence, you may want to disable this feature so that Redis will
+# continue to work as usual even if there are problems with disk,
+# permissions, and so forth.
+stop-writes-on-bgsave-error yes
+
+# Compress string objects using LZF when dump .rdb databases?
+# For default that's set to 'yes' as it's almost always a win.
+# If you want to save some CPU in the saving child set it to 'no' but
+# the dataset will likely be bigger if you have compressible values or keys.
+rdbcompression no
+
+# Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
+# This makes the format more resistant to corruption but there is a performance
+# hit to pay (around 10%) when saving and loading RDB files, so you can disable it
+# for maximum performances.
+#
+# RDB files created with checksum disabled have a checksum of zero that will
+# tell the loading code to skip the check.
+rdbchecksum yes
+
+# The filename where to dump the DB
+dbfilename dump.rdb
+
+# The working directory.
+#
+# The DB will be written inside this directory, with the filename specified
+# above using the 'dbfilename' configuration directive.
+# 
+# The Append Only File will also be created inside this directory.
+# 
+# Note that you must specify a directory here, not a file name.
+# dir ./
+
+# should we toggle this, try a persistent dir w/ iscsi?
+dir /data
+
+################################# REPLICATION #################################
+
+# Master-Slave replication. Use slaveof to make a Redis instance a copy of
+# another Redis server. A few things to understand ASAP about Redis replication.
+#
+# 1) Redis replication is asynchronous, but you can configure a master to
+#    stop accepting writes if it appears to be not connected with at least
+#    a given number of slaves.
+# 2) Redis slaves are able to perform a partial resynchronization with the
+#    master if the replication link is lost for a relatively small amount of
+#    time. You may want to configure the replication backlog size (see the next
+#    sections of this file) with a sensible value depending on your needs.
+# 3) Replication is automatic and does not need user intervention. After a
+#    network partition slaves automatically try to reconnect to masters
+#    and resynchronize with them.
+#
+# slaveof <masterip> <masterport>
+
+# If the master is password protected (using the "requirepass" configuration
+# directive below) it is possible to tell the slave to authenticate before
+# starting the replication synchronization process, otherwise the master will
+# refuse the slave request.
+#
+# masterauth <master-password>
+
+# When a slave loses its connection with the master, or when the replication
+# is still in progress, the slave can act in two different ways:
+#
+# 1) if slave-serve-stale-data is set to 'yes' (the default) the slave will
+#    still reply to client requests, possibly with out of date data, or the
+#    data set may just be empty if this is the first synchronization.
+#
+# 2) if slave-serve-stale-data is set to 'no' the slave will reply with
+#    an error "SYNC with master in progress" to all the kind of commands
+#    but to INFO and SLAVEOF.
+#
+
+# experimental change to "no"  hopefully this will highlight when there are failures 
+# at the consistency level (jay)
+slave-serve-stale-data no
+
+# You can configure a slave instance to accept writes or not. Writing against
+# a slave instance may be useful to store some ephemeral data (because data
+# written on a slave will be easily deleted after resync with the master) but
+# may also cause problems if clients are writing to it because of a
+# misconfiguration.
+#
+# Since Redis 2.6 by default slaves are read-only.
+#
+# Note: read only slaves are not designed to be exposed to untrusted clients
+# on the internet. It's just a protection layer against misuse of the instance.
+# Still a read only slave exports by default all the administrative commands
+# such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
+# security of read only slaves using 'rename-command' to shadow all the
+# administrative / dangerous commands.
+slave-read-only yes
+
+# Slaves send PINGs to server in a predefined interval. It's possible to change
+# this interval with the repl_ping_slave_period option. The default value is 10
+# seconds.
+#
+# repl-ping-slave-period 10
+
+# The following option sets the replication timeout for:
+#
+# 1) Bulk transfer I/O during SYNC, from the point of view of slave.
+# 2) Master timeout from the point of view of slaves (data, pings).
+# 3) Slave timeout from the point of view of masters (REPLCONF ACK pings).
+#
+# It is important to make sure that this value is greater than the value
+# specified for repl-ping-slave-period otherwise a timeout will be detected
+# every time there is low traffic between the master and the slave.
+#
+# repl-timeout 60
+
+# Disable TCP_NODELAY on the slave socket after SYNC?
+#
+# If you select "yes" Redis will use a smaller number of TCP packets and
+# less bandwidth to send data to slaves. But this can add a delay for
+# the data to appear on the slave side, up to 40 milliseconds with
+# Linux kernels using a default configuration.
+#
+# If you select "no" the delay for data to appear on the slave side will
+# be reduced but more bandwidth will be used for replication.
+#
+# By default we optimize for low latency, but in very high traffic conditions
+# or when the master and slaves are many hops away, turning this to "yes" may
+# be a good idea.
+repl-disable-tcp-nodelay no
+
+# Set the replication backlog size. The backlog is a buffer that accumulates
+# slave data when slaves are disconnected for some time, so that when a slave
+# wants to reconnect again, often a full resync is not needed, but a partial
+# resync is enough, just passing the portion of data the slave missed while
+# disconnected.
+#
+# The biggest the replication backlog, the longer the time the slave can be
+# disconnected and later be able to perform a partial resynchronization.
+#
+# The backlog is only allocated once there is at least a slave connected.
+#
+# repl-backlog-size 1mb
+
+# After a master has no longer connected slaves for some time, the backlog
+# will be freed. The following option configures the amount of seconds that
+# need to elapse, starting from the time the last slave disconnected, for
+# the backlog buffer to be freed.
+#
+# A value of 0 means to never release the backlog.
+#
+# repl-backlog-ttl 3600
+
+# The slave priority is an integer number published by Redis in the INFO output.
+# It is used by Redis Sentinel in order to select a slave to promote into a
+# master if the master is no longer working correctly.
+#
+# A slave with a low priority number is considered better for promotion, so
+# for instance if there are three slaves with priority 10, 100, 25 Sentinel will
+# pick the one with priority 10, that is the lowest.
+#
+# However a special priority of 0 marks the slave as not able to perform the
+# role of master, so a slave with priority of 0 will never be selected by
+# Redis Sentinel for promotion.
+#
+# By default the priority is 100.
+slave-priority 100
+
+# It is possible for a master to stop accepting writes if there are less than
+# N slaves connected, having a lag less or equal than M seconds.
+#
+# The N slaves need to be in "online" state.
+#
+# The lag in seconds, that must be <= the specified value, is calculated from
+# the last ping received from the slave, that is usually sent every second.
+#
+# This option does not GUARANTEES that N replicas will accept the write, but
+# will limit the window of exposure for lost writes in case not enough slaves
+# are available, to the specified number of seconds.
+#
+# For example to require at least 3 slaves with a lag <= 10 seconds use:
+#
+# min-slaves-to-write 3
+# min-slaves-max-lag 10
+#
+# Setting one or the other to 0 disables the feature.
+#
+# By default min-slaves-to-write is set to 0 (feature disabled) and
+# min-slaves-max-lag is set to 10.
+
+################################## SECURITY ###################################
+
+# Require clients to issue AUTH <PASSWORD> before processing any other
+# commands.  This might be useful in environments in which you do not trust
+# others with access to the host running redis-server.
+#
+# This should stay commented out for backward compatibility and because most
+# people do not need auth (e.g. they run their own servers).
+# 
+# Warning: since Redis is pretty fast an outside user can try up to
+# 150k passwords per second against a good box. This means that you should
+# use a very strong password otherwise it will be very easy to break.
+#
+# requirepass foobared
+
+# Command renaming.
+#
+# It is possible to change the name of dangerous commands in a shared
+# environment. For instance the CONFIG command may be renamed into something
+# hard to guess so that it will still be available for internal-use tools
+# but not available for general clients.
+#
+# Example:
+#
+# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
+#
+# It is also possible to completely kill a command by renaming it into
+# an empty string:
+#
+# rename-command CONFIG ""
+#
+# Please note that changing the name of commands that are logged into the
+# AOF file or transmitted to slaves may cause problems.
+
+################################### LIMITS ####################################
+
+# Set the max number of connected clients at the same time. By default
+# this limit is set to 10000 clients, however if the Redis server is not
+# able to configure the process file limit to allow for the specified limit
+# the max number of allowed clients is set to the current file limit
+# minus 32 (as Redis reserves a few file descriptors for internal uses).
+#
+# Once the limit is reached Redis will close all the new connections sending
+# an error 'max number of clients reached'.
+#
+# maxclients 10000
+
+# Don't use more memory than the specified amount of bytes.
+# When the memory limit is reached Redis will try to remove keys
+# according to the eviction policy selected (see maxmemory-policy).
+#
+# If Redis can't remove keys according to the policy, or if the policy is
+# set to 'noeviction', Redis will start to reply with errors to commands
+# that would use more memory, like SET, LPUSH, and so on, and will continue
+# to reply to read-only commands like GET.
+#
+# This option is usually useful when using Redis as an LRU cache, or to set
+# a hard memory limit for an instance (using the 'noeviction' policy).
+#
+# WARNING: If you have slaves attached to an instance with maxmemory on,
+# the size of the output buffers needed to feed the slaves are subtracted
+# from the used memory count, so that network problems / resyncs will
+# not trigger a loop where keys are evicted, and in turn the output
+# buffer of slaves is full with DELs of keys evicted triggering the deletion
+# of more keys, and so forth until the database is completely emptied.
+#
+# In short... if you have slaves attached it is suggested that you set a lower
+# limit for maxmemory so that there is some free RAM on the system for slave
+# output buffers (but this is not needed if the policy is 'noeviction').
+#
+# maxmemory <bytes>
+
+# MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
+# is reached. You can select among five behaviors:
+# 
+# volatile-lru -> remove the key with an expire set using an LRU algorithm
+# allkeys-lru -> remove any key accordingly to the LRU algorithm
+# volatile-random -> remove a random key with an expire set
+# allkeys-random -> remove a random key, any key
+# volatile-ttl -> remove the key with the nearest expire time (minor TTL)
+# noeviction -> don't expire at all, just return an error on write operations
+# 
+# Note: with any of the above policies, Redis will return an error on write
+#       operations, when there are not suitable keys for eviction.
+#
+#       At the date of writing this commands are: set setnx setex append
+#       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
+#       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
+#       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
+#       getset mset msetnx exec sort
+#
+# The default is:
+#
+# maxmemory-policy volatile-lru
+
+# LRU and minimal TTL algorithms are not precise algorithms but approximated
+# algorithms (in order to save memory), so you can select as well the sample
+# size to check. For instance for default Redis will check three keys and
+# pick the one that was used less recently, you can change the sample size
+# using the following configuration directive.
+#
+# maxmemory-samples 3
+
+############################## APPEND ONLY MODE ###############################
+
+# By default Redis asynchronously dumps the dataset on disk. This mode is
+# good enough in many applications, but an issue with the Redis process or
+# a power outage may result into a few minutes of writes lost (depending on
+# the configured save points).
+#
+# The Append Only File is an alternative persistence mode that provides
+# much better durability. For instance using the default data fsync policy
+# (see later in the config file) Redis can lose just one second of writes in a
+# dramatic event like a server power outage, or a single write if something
+# wrong with the Redis process itself happens, but the operating system is
+# still running correctly.
+#
+# AOF and RDB persistence can be enabled at the same time without problems.
+# If the AOF is enabled on startup Redis will load the AOF, that is the file
+# with the better durability guarantees.
+#
+# Please check http://redis.io/topics/persistence for more information.
+
+appendonly yes
+
+# The name of the append only file (default: "appendonly.aof")
+
+appendfilename "appendonly.aof"
+
+# The fsync() call tells the Operating System to actually write data on disk
+# instead to wait for more data in the output buffer. Some OS will really flush 
+# data on disk, some other OS will just try to do it ASAP.
+#
+# Redis supports three different modes:
+#
+# no: don't fsync, just let the OS flush the data when it wants. Faster.
+# always: fsync after every write to the append only log . Slow, Safest.
+# everysec: fsync only one time every second. Compromise.
+#
+# The default is "everysec", as that's usually the right compromise between
+# speed and data safety. It's up to you to understand if you can relax this to
+# "no" that will let the operating system flush the output buffer when
+# it wants, for better performances (but if you can live with the idea of
+# some data loss consider the default persistence mode that's snapshotting),
+# or on the contrary, use "always" that's very slow but a bit safer than
+# everysec.
+#
+# More details please check the following article:
+# http://antirez.com/post/redis-persistence-demystified.html
+#
+# If unsure, use "everysec".
+
+# appendfsync always
+appendfsync everysec
+# appendfsync no
+
+# When the AOF fsync policy is set to always or everysec, and a background
+# saving process (a background save or AOF log background rewriting) is
+# performing a lot of I/O against the disk, in some Linux configurations
+# Redis may block too long on the fsync() call. Note that there is no fix for
+# this currently, as even performing fsync in a different thread will block
+# our synchronous write(2) call.
+#
+# In order to mitigate this problem it's possible to use the following option
+# that will prevent fsync() from being called in the main process while a
+# BGSAVE or BGREWRITEAOF is in progress.
+#
+# This means that while another child is saving, the durability of Redis is
+# the same as "appendfsync none". In practical terms, this means that it is
+# possible to lose up to 30 seconds of log in the worst scenario (with the
+# default Linux settings).
+# 
+# If you have latency problems turn this to "yes". Otherwise leave it as
+# "no" that is the safest pick from the point of view of durability.
+
+no-appendfsync-on-rewrite no
+
+# Automatic rewrite of the append only file.
+# Redis is able to automatically rewrite the log file implicitly calling
+# BGREWRITEAOF when the AOF log size grows by the specified percentage.
+# 
+# This is how it works: Redis remembers the size of the AOF file after the
+# latest rewrite (if no rewrite has happened since the restart, the size of
+# the AOF at startup is used).
+#
+# This base size is compared to the current size. If the current size is
+# bigger than the specified percentage, the rewrite is triggered. Also
+# you need to specify a minimal size for the AOF file to be rewritten, this
+# is useful to avoid rewriting the AOF file even if the percentage increase
+# is reached but it is still pretty small.
+#
+# Specify a percentage of zero in order to disable the automatic AOF
+# rewrite feature.
+
+auto-aof-rewrite-percentage 100
+
+# another experimental feature
+auto-aof-rewrite-min-size 1 
+
+# An AOF file may be found to be truncated at the end during the Redis
+# startup process, when the AOF data gets loaded back into memory.
+# This may happen when the system where Redis is running
+# crashes, especially when an ext4 filesystem is mounted without the
+# data=ordered option (however this can't happen when Redis itself
+# crashes or aborts but the operating system still works correctly).
+#
+# Redis can either exit with an error when this happens, or load as much
+# data as possible (the default now) and start if the AOF file is found
+# to be truncated at the end. The following option controls this behavior.
+#
+# If aof-load-truncated is set to yes, a truncated AOF file is loaded and
+# the Redis server starts emitting a log to inform the user of the event.
+# Otherwise if the option is set to no, the server aborts with an error
+# and refuses to start. When the option is set to no, the user requires
+# to fix the AOF file using the "redis-check-aof" utility before to restart
+# the server.
+#
+# Note that if the AOF file will be found to be corrupted in the middle
+# the server will still exit with an error. This option only applies when
+# Redis will try to read more data from the AOF file but not enough bytes
+# will be found.
+aof-load-truncated yes
+
+################################ LUA SCRIPTING  ###############################
+
+# Max execution time of a Lua script in milliseconds.
+#
+# If the maximum execution time is reached Redis will log that a script is
+# still in execution after the maximum allowed time and will start to
+# reply to queries with an error.
+#
+# When a long running script exceed the maximum execution time only the
+# SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
+# used to stop a script that did not yet called write commands. The second
+# is the only way to shut down the server in the case a write commands was
+# already issue by the script but the user don't want to wait for the natural
+# termination of the script.
+#
+# Set it to 0 or a negative value for unlimited execution without warnings.
+lua-time-limit 5000
+
+################################## SLOW LOG ###################################
+
+# The Redis Slow Log is a system to log queries that exceeded a specified
+# execution time. The execution time does not include the I/O operations
+# like talking with the client, sending the reply and so forth,
+# but just the time needed to actually execute the command (this is the only
+# stage of command execution where the thread is blocked and can not serve
+# other requests in the meantime).
+# 
+# You can configure the slow log with two parameters: one tells Redis
+# what is the execution time, in microseconds, to exceed in order for the
+# command to get logged, and the other parameter is the length of the
+# slow log. When a new command is logged the oldest one is removed from the
+# queue of logged commands.
+
+# The following time is expressed in microseconds, so 1000000 is equivalent
+# to one second. Note that a negative number disables the slow log, while
+# a value of zero forces the logging of every command.
+slowlog-log-slower-than 10000
+
+# There is no limit to this length. Just be aware that it will consume memory.
+# You can reclaim memory used by the slow log with SLOWLOG RESET.
+slowlog-max-len 128
+
+################################ LATENCY MONITOR ##############################
+
+# The Redis latency monitoring subsystem samples different operations
+# at runtime in order to collect data related to possible sources of
+# latency of a Redis instance.
+#
+# Via the LATENCY command this information is available to the user that can
+# print graphs and obtain reports.
+#
+# The system only logs operations that were performed in a time equal or
+# greater than the amount of milliseconds specified via the
+# latency-monitor-threshold configuration directive. When its value is set
+# to zero, the latency monitor is turned off.
+#
+# By default latency monitoring is disabled since it is mostly not needed
+# if you don't have latency issues, and collecting data has a performance
+# impact, that while very small, can be measured under big load. Latency
+# monitoring can easily be enalbed at runtime using the command
+# "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
+latency-monitor-threshold 0
+
+############################# Event notification ##############################
+
+# Redis can notify Pub/Sub clients about events happening in the key space.
+# This feature is documented at http://redis.io/topics/notifications
+# 
+# For instance if keyspace events notification is enabled, and a client
+# performs a DEL operation on key "foo" stored in the Database 0, two
+# messages will be published via Pub/Sub:
+#
+# PUBLISH __keyspace@0__:foo del
+# PUBLISH __keyevent@0__:del foo
+#
+# It is possible to select the events that Redis will notify among a set
+# of classes. Every class is identified by a single character:
+#
+#  K     Keyspace events, published with __keyspace@<db>__ prefix.
+#  E     Keyevent events, published with __keyevent@<db>__ prefix.
+#  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
+#  $     String commands
+#  l     List commands
+#  s     Set commands
+#  h     Hash commands
+#  z     Sorted set commands
+#  x     Expired events (events generated every time a key expires)
+#  e     Evicted events (events generated when a key is evicted for maxmemory)
+#  A     Alias for g$lshzxe, so that the "AKE" string means all the events.
+#
+#  The "notify-keyspace-events" takes as argument a string that is composed
+#  by zero or multiple characters. The empty string means that notifications
+#  are disabled at all.
+#
+#  Example: to enable list and generic events, from the point of view of the
+#           event name, use:
+#
+#  notify-keyspace-events Elg
+#
+#  Example 2: to get the stream of the expired keys subscribing to channel
+#             name __keyevent@0__:expired use:
+#
+#  notify-keyspace-events Ex
+#
+#  By default all notifications are disabled because most users don't need
+#  this feature and the feature has some overhead. Note that if you don't
+#  specify at least one of K or E, no events will be delivered.
+notify-keyspace-events "KEg$lshzxeA" # lots of logging, also experimental
+
+############################### ADVANCED CONFIG ###############################
+
+# Hashes are encoded using a memory efficient data structure when they have a
+# small number of entries, and the biggest entry does not exceed a given
+# threshold. These thresholds can be configured using the following directives.
+hash-max-ziplist-entries 512
+hash-max-ziplist-value 64
+
+# Similarly to hashes, small lists are also encoded in a special way in order
+# to save a lot of space. The special representation is only used when
+# you are under the following limits:
+list-max-ziplist-entries 512
+list-max-ziplist-value 64
+
+# Sets have a special encoding in just one case: when a set is composed
+# of just strings that happens to be integers in radix 10 in the range
+# of 64 bit signed integers.
+# The following configuration setting sets the limit in the size of the
+# set in order to use this special memory saving encoding.
+set-max-intset-entries 512
+
+# Similarly to hashes and lists, sorted sets are also specially encoded in
+# order to save a lot of space. This encoding is only used when the length and
+# elements of a sorted set are below the following limits:
+zset-max-ziplist-entries 128
+zset-max-ziplist-value 64
+
+# HyperLogLog sparse representation bytes limit. The limit includes the
+# 16 bytes header. When an HyperLogLog using the sparse representation crosses
+# this limit, it is converted into the dense representation.
+#
+# A value greater than 16000 is totally useless, since at that point the
+# dense representation is more memory efficient.
+# 
+# The suggested value is ~ 3000 in order to have the benefits of
+# the space efficient encoding without slowing down too much PFADD,
+# which is O(N) with the sparse encoding. The value can be raised to
+# ~ 10000 when CPU is not a concern, but space is, and the data set is
+# composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
+hll-sparse-max-bytes 3000
+
+# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
+# order to help rehashing the main Redis hash table (the one mapping top-level
+# keys to values). The hash table implementation Redis uses (see dict.c)
+# performs a lazy rehashing: the more operation you run into a hash table
+# that is rehashing, the more rehashing "steps" are performed, so if the
+# server is idle the rehashing is never complete and some more memory is used
+# by the hash table.
+# 
+# The default is to use this millisecond 10 times every second in order to
+# active rehashing the main dictionaries, freeing memory when possible.
+#
+# If unsure:
+# use "activerehashing no" if you have hard latency requirements and it is
+# not a good thing in your environment that Redis can reply form time to time
+# to queries with 2 milliseconds delay.
+#
+# use "activerehashing yes" if you don't have such hard requirements but
+# want to free memory asap when possible.
+activerehashing yes
+
+# The client output buffer limits can be used to force disconnection of clients
+# that are not reading data from the server fast enough for some reason (a
+# common reason is that a Pub/Sub client can't consume messages as fast as the
+# publisher can produce them).
+#
+# The limit can be set differently for the three different classes of clients:
+#
+# normal -> normal clients including MONITOR clients
+# slave  -> slave clients
+# pubsub -> clients subscribed to at least one pubsub channel or pattern
+#
+# The syntax of every client-output-buffer-limit directive is the following:
+#
+# client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
+#
+# A client is immediately disconnected once the hard limit is reached, or if
+# the soft limit is reached and remains reached for the specified number of
+# seconds (continuously).
+# So for instance if the hard limit is 32 megabytes and the soft limit is
+# 16 megabytes / 10 seconds, the client will get disconnected immediately
+# if the size of the output buffers reach 32 megabytes, but will also get
+# disconnected if the client reaches 16 megabytes and continuously overcomes
+# the limit for 10 seconds.
+#
+# By default normal clients are not limited because they don't receive data
+# without asking (in a push way), but just after a request, so only
+# asynchronous clients may create a scenario where data is requested faster
+# than it can read.
+#
+# Instead there is a default limit for pubsub and slave clients, since
+# subscribers and slaves receive data in a push fashion.
+#
+# Both the hard or the soft limit can be disabled by setting them to zero.
+client-output-buffer-limit normal 0 0 0
+client-output-buffer-limit slave 256mb 64mb 60
+client-output-buffer-limit pubsub 32mb 8mb 60
+
+# Redis calls an internal function to perform many background tasks, like
+# closing connections of clients in timeout, purging expired keys that are
+# never requested, and so forth.
+#
+# Not all tasks are performed with the same frequency, but Redis checks for
+# tasks to perform accordingly to the specified "hz" value.
+#
+# By default "hz" is set to 10. Raising the value will use more CPU when
+# Redis is idle, but at the same time will make Redis more responsive when
+# there are many keys expiring at the same time, and timeouts may be
+# handled with more precision.
+#
+# The range is between 1 and 500, however a value over 100 is usually not
+# a good idea. Most users should use the default of 10 and raise this up to
+# 100 only in environments where very low latency is required.
+hz 10
+
+# When a child rewrites the AOF file, if the following option is enabled
+# the file will be fsync-ed every 32 MB of data generated. This is useful
+# in order to commit the file to the disk more incrementally and avoid
+# big latency spikes.
+aof-rewrite-incremental-fsync yes
+

examples/k8petstore/web-server/Dockerfile

@@ -0,0 +1,21 @@
+FROM google/golang:latest
+
+# Add source to gopath.  This is defacto required for go apps.
+ADD ./src /gopath/src/
+ADD ./static /tmp/static
+ADD ./test.sh /opt/test.sh
+RUN chmod 777 /opt/test.sh
+# $GOPATH/[src/a/b/c]
+# go build a/b/c
+# go run main
+
+# So that we can easily run and install
+WORKDIR /gopath/src/
+
+# Install the code (the executables are in the main dir)  This will get the deps also.
+RUN go get main
+#RUN go build main
+
+# Expected that you will override this in production kubernetes.
+ENV STATIC_FILES /tmp/static
+CMD /gopath/bin/main

examples/k8petstore/web-server/src/github.com/codegangsta/negroni

@@ -0,0 +1 @@
+Subproject commit 1dd3ab0ff59e13f5b73dcbf70703710aebe50d2f

examples/k8petstore/web-server/src/github.com/garyburd/redigo

@@ -0,0 +1 @@
+Subproject commit 535138d7bcd717d6531c701ef5933d98b1866257

examples/k8petstore/web-server/src/github.com/gorilla/context

@@ -0,0 +1 @@
+Subproject commit 215affda49addc4c8ef7e2534915df2c8c35c6cd

examples/k8petstore/web-server/src/github.com/gorilla/mux

@@ -0,0 +1 @@
+Subproject commit 8096f47503459bcc74d1f4c487b7e6e42e5746b5

examples/k8petstore/web-server/src/github.com/xyproto/simpleredis

@@ -0,0 +1 @@
+Subproject commit 5292687f5379e01054407da44d7c4590a61fd3de

examples/k8petstore/web-server/src/main/PetStoreBook.go

@@ -0,0 +1,207 @@
+package main
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+//package main
+
+import (
+    "encoding/json"
+    "net/http"
+    "os"
+    "strings"
+    "fmt"
+    "github.com/codegangsta/negroni"
+    "github.com/gorilla/mux"
+    "github.com/xyproto/simpleredis"
+)
+
+//return the path to static assets (i.e. index.html)
+func pathToStaticContents() (string) {
+    var static_content = os.Getenv("STATIC_FILES");
+    // Take a wild guess.  This will work in dev environment.
+    if static_content == "" {
+        println("*********** WARNING: DIDNT FIND ENV VAR 'STATIC_FILES', guessing your running in dev.")
+        static_content = "../../static/"
+    } else {
+        println("=========== Read ENV 'STATIC_FILES', path to assets : " + static_content);
+    }
+
+    //Die if no the static files are missing.
+    _, err := os.Stat(static_content)
+    if err != nil {
+        println("*********** os.Stat failed on " + static_content + " This means no static files are available.  Dying...");
+        os.Exit(2);
+    }
+    return static_content;
+}
+
+func main() {
+
+    var connection = os.Getenv("REDISMASTER_SERVICE_HOST")+":"+os.Getenv("REDISMASTER_SERVICE_PORT");    
+
+    if connection == ":" {
+        print("WARNING ::: If in kube, this is a failure: Missing env variable REDISMASTER_SERVICE_HOST");
+        print("WARNING ::: Attempting to connect redis localhost.")
+        connection="127.0.0.1:6379";
+    } else {
+        print("Found redis master host "+ os.Getenv("REDISMASTER_SERVICE_PORT"));
+        connection = os.Getenv("REDISMASTER_SERVICE_HOST") + ":" + os.Getenv("REDISMASTER_SERVICE_PORT");
+    }
+
+    println("Now connecting to : " + connection)
+    /**
+    *  Create a connection pool.  ?The pool pointer will otherwise
+    *  not be of any use.?https://gist.github.com/jayunit100/1d00e6d343056401ef00
+    */
+    pool = simpleredis.NewConnectionPoolHost(connection)
+
+    println("Connection pool established : " + connection)
+
+    defer pool.Close()
+
+    r := mux.NewRouter()
+
+    println("Router created ")
+
+    /**
+    * Define a REST path.
+    *  - The parameters (key) can be accessed via mux.Vars.
+    *  - The Methods (GET) will be bound to a handler function.
+    */
+    r.Path("/info").Methods("GET").HandlerFunc(InfoHandler)
+    r.Path("/lrange/{key}").Methods("GET").HandlerFunc(ListRangeHandler)
+    r.Path("/rpush/{key}/{value}").Methods("GET").HandlerFunc(ListPushHandler)
+    r.Path("/llen").Methods("GET").HandlerFunc(LLENHandler)
+
+    //for dev environment, the site is one level up...
+
+    r.PathPrefix("/").Handler(http.FileServer(http.Dir( pathToStaticContents() )))
+
+    r.Path("/env").Methods("GET").HandlerFunc(EnvHandler)
+
+    list := simpleredis.NewList(pool, "k8petstore")
+    HandleError(nil, list.Add("jayunit100"))
+    HandleError(nil, list.Add("tstclaire"))
+    HandleError(nil, list.Add("rsquared"))
+
+    // Verify that this is 3 on startup.
+    infoL := HandleError(pool.Get(0).Do("LLEN","k8petstore")).(int64) 
+    fmt.Printf("\n=========== Starting DB has %d elements \n", infoL)
+    if infoL < 3 {
+        print("Not enough entries in DB.  something is wrong w/ redis querying")
+        print(infoL)
+        panic("Failed ... ")
+    }  
+
+
+    println("===========  Now launching negroni...this might take a second...")
+    n := negroni.Classic()
+    n.UseHandler(r)
+    n.Run(":3000")
+    println("Done ! Web app is now running.")
+
+   
+   
+}
+
+/**
+* the Pool will be populated on startup,
+* it will be an instance of a connection pool.
+* Hence, we reference its address rather than copying.
+*/
+var pool *simpleredis.ConnectionPool
+
+/**
+*  REST
+*  input: key
+*
+*  Writes  all members to JSON.
+*/
+func ListRangeHandler(rw http.ResponseWriter, req *http.Request) {
+    println("ListRangeHandler")
+
+    key := mux.Vars(req)["key"]
+
+    list := simpleredis.NewList(pool, key)
+
+    //members := HandleError(list.GetAll()).([]string)
+    members := HandleError(list.GetLastN(4)).([]string)
+
+    print(members)
+    membersJSON := HandleError(json.MarshalIndent(members, "", "  ")).([]byte)
+
+    print("RETURN MEMBERS = "+string(membersJSON))
+    rw.Write(membersJSON)
+}
+
+func LLENHandler(rw http.ResponseWriter, req *http.Request) {
+    println("=========== LLEN HANDLER")
+
+    infoL := HandleError(pool.Get(0).Do("LLEN","k8petstore")).(int64)
+    fmt.Printf("=========== LLEN is %d ", infoL)
+    lengthJSON := HandleError(json.MarshalIndent(infoL, "", "  ")).([]byte)
+    fmt.Printf("================ LLEN json is %s", infoL)
+    
+    print("RETURN LEN = "+string(lengthJSON))
+    rw.Write(lengthJSON)
+
+}
+
+func ListPushHandler(rw http.ResponseWriter, req *http.Request) {
+    println("ListPushHandler")
+
+    /**
+    *  Expect a key and value as input.
+    *
+    */
+    key := mux.Vars(req)["key"]
+    value := mux.Vars(req)["value"]
+
+    println("New list " + key + " " + value)
+    list := simpleredis.NewList(pool, key)
+    HandleError(nil, list.Add(value))
+    ListRangeHandler(rw, req)
+}
+
+func InfoHandler(rw http.ResponseWriter, req *http.Request) {
+    println("InfoHandler")
+
+    info := HandleError(pool.Get(0).Do("INFO")).([]byte)
+    rw.Write(info)
+}
+
+func EnvHandler(rw http.ResponseWriter, req *http.Request) {
+    println("EnvHandler")
+
+    environment := make(map[string]string)
+    for _, item := range os.Environ() {
+        splits := strings.Split(item, "=")
+        key := splits[0]
+        val := strings.Join(splits[1:], "=")
+        environment[key] = val
+    }
+
+    envJSON := HandleError(json.MarshalIndent(environment, "", "  ")).([]byte)
+    rw.Write(envJSON)
+}
+
+func HandleError(result interface{}, err error) (r interface{}) {
+    if err != nil {
+        print("ERROR :  " + err.Error())
+        //panic(err)
+    }
+    return result
+}

examples/k8petstore/web-server/static/histogram.js

@@ -0,0 +1,39 @@
+//var data = [4, 8, 15, 16, 23, 42];
+
+function defaults(){
+
+    Chart.defaults.global.animation = false;
+
+}
+
+function f(data2) {
+
+    defaults();
+
+    // Get context with jQuery - using jQuery's .get() method.
+    var ctx = $("#myChart").get(0).getContext("2d");
+    ctx.width  = $(window).width()*1.5;
+    ctx.width  = $(window).height *.5;
+
+    // This will get the first returned node in the jQuery collection.
+    var myNewChart = new Chart(ctx);
+
+    var data = {
+        labels: Array.apply(null, Array(data2.length)).map(function (_, i) {return i;}),
+        datasets: [
+            {
+                label: "My First dataset",
+                fillColor: "rgba(220,220,220,0.2)",
+                strokeColor: "rgba(220,220,220,1)",
+                pointColor: "rgba(220,220,220,1)",
+                pointStrokeColor: "#fff",
+                pointHighlightFill: "#fff",
+                pointHighlightStroke: "rgba(220,220,220,1)",
+                data: data2
+            }
+        ]
+    };
+
+    var myLineChart = new Chart(ctx).Line(data);
+}
+

examples/k8petstore/web-server/static/index.html

@@ -0,0 +1,47 @@
+<!DOCTYPE html>
+<html lang="en">
+<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
+<!-- d3 is used by histogram.js
+<script src="http://d3js.org/d3.v3.min.js"  charset="utf-8"></script>
+-->
+<script src="https://raw.githubusercontent.com/nnnick/Chart.js/master/Chart.js"></script>
+<script src="script.js"></script>
+<script src="histogram.js"></script>
+
+  <head>
+    <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
+    <meta charset="utf-8">
+    <meta content="width=device-width" name="viewport">
+    <link href="/style.css" rel="stylesheet">
+    <title>((( - PRODUCTION -))) Guestbook</title>
+  </head>
+  <body>
+
+    <TABLE>
+        <TR>
+            <TD>
+                <div id="k8petstore-entries">
+                    <p>Waiting for database connection...This will get overwritten...</p>
+                </div>
+            </TD>
+
+            <TD>
+                <div id="header">
+                    <h1>k8-bps.</h1>
+                </div><br>
+                <div>
+                    <p><h2 id="k8petstore-host-address"></h2></p>
+                    <p><a href="/env">/env</a>
+                        <a href="/info">/info</a></p>
+                </div>
+            </TD>
+        </TR>
+        <TR >
+            <TD colspan="2">
+                <canvas id="myChart" width="2000" height="600"></canvas>
+            </TD>
+        </TR>
+    </TABLE>
+  </body>
+
+</html>

examples/k8petstore/web-server/static/script.js

@@ -0,0 +1,72 @@
+$(document).ready(function() {
+
+  var max_trials=1000
+
+  var headerTitleElement = $("#header h1");
+  var entriesElement = $("#k8petstore-entries");
+  var hostAddressElement = $("#k8petstore-host-address");
+  var currentEntries = []
+
+  var updateEntryCount = function(data, trial) {
+      if(currentEntries.length > 1000)
+        currentEntries.splice(0,100);
+      //console.info("entry count " + data) ;
+      currentEntries[trial]=data ;
+  }
+
+  var updateEntries = function(data) {
+    entriesElement.empty();
+      //console.info("data - > " + Math.random())
+      //uncommend for debugging...
+      //entriesElement.append("<br><br> CURRENT TIME :  "+ $.now() +"<br><br>TOTAL entries :  "+ JSON.stringify(currentEntries)+"<br><br>")
+      var c1 = currentEntries[currentEntries.length-1]
+      var c2 = currentEntries[currentEntries.length-2]
+      entriesElement.append("<br><br> CURRENT TIME :  "+ $.now() +"<br><br>TOTAL entries :  "+ c1 +"<BR>transaction delta " + (c1-c2) +"<br><br>")
+      f(currentEntries);
+    $.each(data, function(key, val) {
+        //console.info(key + " -> " +val);
+        entriesElement.append("<p>" + key + " " + val.substr(0,50) + val.substr(100,150) + "</p>");
+    });
+
+  }
+
+  // colors = purple, blue, red, green, yellow
+  var colors = ["#549", "#18d", "#d31", "#2a4", "#db1"];
+  var randomColor = colors[Math.floor(5 * Math.random())];
+  (
+      function setElementsColor(color) {
+          headerTitleElement.css("color", color);
+      })
+
+        (randomColor);
+
+  hostAddressElement.append(document.URL);
+
+  // Poll every second.
+  (function fetchGuestbook() {
+
+      // Get JSON by running the query, and append
+    $.getJSON("lrange/k8petstore").done(updateEntries).always(
+      function() {
+        setTimeout(fetchGuestbook, 2000);
+      });
+  })();
+
+    (function fetchLength(trial) {
+        $.getJSON("llen").done(
+            function a(llen1){
+                updateEntryCount(llen1, trial)
+            }).always(
+                function() {
+                    // This function is run every 2 seconds.
+                    setTimeout(
+                        function(){
+                            trial+=1 ;
+                            fetchLength(trial);
+                            f();
+                        }, 5000);
+                }
+            )
+    })(0);
+});
+

examples/k8petstore/web-server/static/style.css

@@ -0,0 +1,69 @@
+body, input {
+  color: #123;
+  font-family: "Gill Sans", sans-serif;
+}
+
+div {
+  overflow: hidden;
+  padding: 1em 0;
+  position: relative;
+  text-align: center;
+}
+
+h1, h2, p, input, a {
+  font-weight: 300;
+  margin: 0;
+}
+
+h1 {
+  color: #BDB76B;
+  font-size: 3.5em;
+}
+
+h2 {
+  color: #999;
+}
+
+form {
+  margin: 0 auto;
+  max-width: 50em;
+  text-align: center;
+}
+
+input {
+  border: 0;
+  border-radius: 1000px;
+  box-shadow: inset 0 0 0 2px #BDB76B;
+  display: inline;
+  font-size: 1.5em;
+  margin-bottom: 1em;
+  outline: none;
+  padding: .5em 5%;
+  width: 55%;
+}
+
+form a {
+  background: #BDB76B;
+  border: 0;
+  border-radius: 1000px;
+  color: #FFF;
+  font-size: 1.25em;
+  font-weight: 400;
+  padding: .75em 2em;
+  text-decoration: none;
+  text-transform: uppercase;
+  white-space: normal;
+}
+
+p {
+  font-size: 1.5em;
+  line-height: 1.5;
+}
+.chart div {
+    font: 10px sans-serif;
+    background-color: steelblue;
+    text-align: right;
+    padding: 3px;
+    margin: 1px;
+    color: white;
+}

examples/k8petstore/web-server/test.sh

@@ -0,0 +1,9 @@
+echo "start test of frontend"
+curl localhost:3000/llen
+curl localhost:3000/llen
+curl localhost:3000/llen
+curl localhost:3000/llen
+curl localhost:3000/llen
+curl localhost:3000/llen
+x=`curl localhost:3000/llen`
+echo "done testing frontend result = $x"