Vendor update

2025-09-04 00:14:49 +00:00 · 2017-10-29 11:41:21 +02:00
parent 60574a70bb
commit 84d02e8b42
427 changed files with 76398 additions and 0 deletions
--- a/vendor/github.com/docker/distribution/.gitignore
+++ b/vendor/github.com/docker/distribution/.gitignore
@@ -0,0 +1,37 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test
+*.prof
+
+# never checkin from the bin file (for now)
+bin/*
+
+# Test key files
+*.pem
+
+# Cover profiles
+*.out
+
+# Editor/IDE specific files.
+*.sublime-project
+*.sublime-workspace
--- a/vendor/github.com/docker/distribution/.mailmap
+++ b/vendor/github.com/docker/distribution/.mailmap
@@ -0,0 +1,18 @@
+Stephen J Day <stephen.day@docker.com>  Stephen Day <stevvooe@users.noreply.github.com>
+Stephen J Day <stephen.day@docker.com>  Stephen Day <stevvooe@gmail.com>
+Olivier Gambier <olivier@docker.com>    Olivier Gambier <dmp42@users.noreply.github.com>
+Brian Bland <brian.bland@docker.com>    Brian Bland <r4nd0m1n4t0r@gmail.com>
+Brian Bland <brian.bland@docker.com> Brian Bland <brian.t.bland@gmail.com>
+Josh Hawn <josh.hawn@docker.com>        Josh Hawn <jlhawn@berkeley.edu>
+Richard Scothern <richard.scothern@docker.com> Richard <richard.scothern@gmail.com>
+Richard Scothern <richard.scothern@docker.com> Richard Scothern <richard.scothern@gmail.com>
+Andrew Meredith <andymeredith@gmail.com> Andrew Meredith <kendru@users.noreply.github.com>
+harche <p.harshal@gmail.com> harche <harche@users.noreply.github.com>
+Jessie Frazelle <jessie@docker.com>  <jfrazelle@users.noreply.github.com>
+Sharif Nassar <sharif@mrwacky.com> Sharif Nassar <mrwacky42@users.noreply.github.com>
+Sven Dowideit <SvenDowideit@home.org.au> Sven Dowideit <SvenDowideit@users.noreply.github.com>
+Vincent Giersch <vincent.giersch@ovh.net> Vincent Giersch <vincent@giersch.fr>
+davidli <wenquan.li@hp.com> davidli <wenquan.li@hpe.com>
+Omer Cohen <git@omer.io> Omer Cohen <git@omerc.net>
+Eric Yang <windfarer@gmail.com> Eric Yang <Windfarer@users.noreply.github.com>
+Nikita Tarasov <nikita@mygento.ru> Nikita <luckyraul@users.noreply.github.com>
--- a/vendor/github.com/docker/distribution/AUTHORS
+++ b/vendor/github.com/docker/distribution/AUTHORS
@@ -0,0 +1,182 @@
+a-palchikov <deemok@gmail.com>
+Aaron Lehmann <aaron.lehmann@docker.com>
+Aaron Schlesinger <aschlesinger@deis.com>
+Aaron Vinson <avinson.public@gmail.com>
+Adam Duke <adam.v.duke@gmail.com>
+Adam Enger <adamenger@gmail.com>
+Adrian Mouat <adrian.mouat@gmail.com>
+Ahmet Alp Balkan <ahmetalpbalkan@gmail.com>
+Alex Chan <alex.chan@metaswitch.com>
+Alex Elman <aelman@indeed.com>
+Alexey Gladkov <gladkov.alexey@gmail.com>
+allencloud <allen.sun@daocloud.io>
+amitshukla <ashukla73@hotmail.com>
+Amy Lindburg <amy.lindburg@docker.com>
+Andrew Hsu <andrewhsu@acm.org>
+Andrew Meredith <andymeredith@gmail.com>
+Andrew T Nguyen <andrew.nguyen@docker.com>
+Andrey Kostov <kostov.andrey@gmail.com>
+Andy Goldstein <agoldste@redhat.com>
+Anis Elleuch <vadmeste@gmail.com>
+Anton Tiurin <noxiouz@yandex.ru>
+Antonio Mercado <amercado@thinknode.com>
+Antonio Murdaca <runcom@redhat.com>
+Anusha Ragunathan <anusha@docker.com>
+Arien Holthuizen <aholthuizen@schubergphilis.com>
+Arnaud Porterie <arnaud.porterie@docker.com>
+Arthur Baars <arthur@semmle.com>
+Asuka Suzuki <hello@tanksuzuki.com>
+Avi Miller <avi.miller@oracle.com>
+Ayose Cazorla <ayosec@gmail.com>
+BadZen <dave.trombley@gmail.com>
+Ben Bodenmiller <bbodenmiller@hotmail.com>
+Ben Firshman <ben@firshman.co.uk>
+bin liu <liubin0329@gmail.com>
+Brian Bland <brian.bland@docker.com>
+burnettk <burnettk@gmail.com>
+Carson A <ca@carsonoid.net>
+Cezar Sa Espinola <cezarsa@gmail.com>
+Charles Smith <charles.smith@docker.com>
+Chris Dillon <squarism@gmail.com>
+cuiwei13 <cuiwei13@pku.edu.cn>
+cyli <cyli@twistedmatrix.com>
+Daisuke Fujita <dtanshi45@gmail.com>
+Daniel Huhn <daniel@danielhuhn.de>
+Darren Shepherd <darren@rancher.com>
+Dave Trombley <dave.trombley@gmail.com>
+Dave Tucker <dt@docker.com>
+David Lawrence <david.lawrence@docker.com>
+David Verhasselt <david@crowdway.com>
+David Xia <dxia@spotify.com>
+davidli <wenquan.li@hp.com>
+Dejan Golja <dejan@golja.org>
+Derek McGowan <derek@mcgstyle.net>
+Diogo Mónica <diogo.monica@gmail.com>
+DJ Enriquez <dj.enriquez@infospace.com>
+Donald Huang <don.hcd@gmail.com>
+Doug Davis <dug@us.ibm.com>
+Edgar Lee <edgar.lee@docker.com>
+Eric Yang <windfarer@gmail.com>
+Fabio Berchtold <jamesclonk@jamesclonk.ch>
+Fabio Huser <fabio@fh1.ch>
+farmerworking <farmerworking@gmail.com>
+Felix Yan <felixonmars@archlinux.org>
+Florentin Raud <florentin.raud@gmail.com>
+Frank Chen <frankchn@gmail.com>
+Frederick F. Kautz IV <fkautz@alumni.cmu.edu>
+gabriell nascimento <gabriell@bluesoft.com.br>
+Gleb Schukin <gschukin@ptsecurity.com>
+harche <p.harshal@gmail.com>
+Henri Gomez <henri.gomez@gmail.com>
+Hu Keping <hukeping@huawei.com>
+Hua Wang <wanghua.humble@gmail.com>
+HuKeping <hukeping@huawei.com>
+Ian Babrou <ibobrik@gmail.com>
+igayoso <igayoso@gmail.com>
+Jack Griffin <jackpg14@gmail.com>
+James Findley <jfindley@fastmail.com>
+Jason Freidman <jason.freidman@gmail.com>
+Jason Heiss <jheiss@aput.net>
+Jeff Nickoloff <jeff@allingeek.com>
+Jess Frazelle <acidburn@google.com>
+Jessie Frazelle <jessie@docker.com>
+jhaohai <jhaohai@foxmail.com>
+Jianqing Wang <tsing@jianqing.org>
+Jihoon Chung <jihoon@gmail.com>
+Joao Fernandes <joao.fernandes@docker.com>
+John Mulhausen <john@docker.com>
+John Starks <jostarks@microsoft.com>
+Jon Johnson <jonjohnson@google.com>
+Jon Poler <jonathan.poler@apcera.com>
+Jonathan Boulle <jonathanboulle@gmail.com>
+Jordan Liggitt <jliggitt@redhat.com>
+Josh Chorlton <josh.chorlton@docker.com>
+Josh Hawn <josh.hawn@docker.com>
+Julien Fernandez <julien.fernandez@gmail.com>
+Ke Xu <leonhartx.k@gmail.com>
+Keerthan Mala <kmala@engineyard.com>
+Kelsey Hightower <kelsey.hightower@gmail.com>
+Kenneth Lim <kennethlimcp@gmail.com>
+Kenny Leung <kleung@google.com>
+Li Yi <denverdino@gmail.com>
+Liu Hua <sdu.liu@huawei.com>
+liuchang0812 <liuchang0812@gmail.com>
+Lloyd Ramey <lnr0626@gmail.com>
+Louis Kottmann <louis.kottmann@gmail.com>
+Luke Carpenter <x@rubynerd.net>
+Marcus Martins <marcus@docker.com>
+Mary Anthony <mary@docker.com>
+Matt Bentley <mbentley@mbentley.net>
+Matt Duch <matt@learnmetrics.com>
+Matt Moore <mattmoor@google.com>
+Matt Robenolt <matt@ydekproductions.com>
+Matthew Green <greenmr@live.co.uk>
+Michael Prokop <mika@grml.org>
+Michal Minar <miminar@redhat.com>
+Michal Minář <miminar@redhat.com>
+Mike Brown <brownwm@us.ibm.com>
+Miquel Sabaté <msabate@suse.com>
+Misty Stanley-Jones <misty@apache.org>
+Misty Stanley-Jones <misty@docker.com>
+Morgan Bauer <mbauer@us.ibm.com>
+moxiegirl <mary@docker.com>
+Nathan Sullivan <nathan@nightsys.net>
+nevermosby <robolwq@qq.com>
+Nghia Tran <tcnghia@gmail.com>
+Nikita Tarasov <nikita@mygento.ru>
+Noah Treuhaft <noah.treuhaft@docker.com>
+Nuutti Kotivuori <nuutti.kotivuori@poplatek.fi>
+Oilbeater <liumengxinfly@gmail.com>
+Olivier Gambier <olivier@docker.com>
+Olivier Jacques <olivier.jacques@hp.com>
+Omer Cohen <git@omer.io>
+Patrick Devine <patrick.devine@docker.com>
+Phil Estes <estesp@linux.vnet.ibm.com>
+Philip Misiowiec <philip@atlashealth.com>
+Pierre-Yves Ritschard <pyr@spootnik.org>
+Qiao Anran <qiaoanran@gmail.com>
+Randy Barlow <randy@electronsweatshop.com>
+Richard Scothern <richard.scothern@docker.com>
+Rodolfo Carvalho <rhcarvalho@gmail.com>
+Rusty Conover <rusty@luckydinosaur.com>
+Sean Boran <Boran@users.noreply.github.com>
+Sebastiaan van Stijn <github@gone.nl>
+Sebastien Coavoux <s.coavoux@free.fr>
+Serge Dubrouski <sergeyfd@gmail.com>
+Sharif Nassar <sharif@mrwacky.com>
+Shawn Falkner-Horine <dreadpirateshawn@gmail.com>
+Shreyas Karnik <karnik.shreyas@gmail.com>
+Simon Thulbourn <simon+github@thulbourn.com>
+spacexnice <yaoyao.xyy@alibaba-inc.com>
+Spencer Rinehart <anubis@overthemonkey.com>
+Stan Hu <stanhu@gmail.com>
+Stefan Majewsky <stefan.majewsky@sap.com>
+Stefan Weil <sw@weilnetz.de>
+Stephen J Day <stephen.day@docker.com>
+Sungho Moon <sungho.moon@navercorp.com>
+Sven Dowideit <SvenDowideit@home.org.au>
+Sylvain Baubeau <sbaubeau@redhat.com>
+Ted Reed <ted.reed@gmail.com>
+tgic <farmer1992@gmail.com>
+Thomas Sjögren <konstruktoid@users.noreply.github.com>
+Tianon Gravi <admwiggin@gmail.com>
+Tibor Vass <teabee89@gmail.com>
+Tonis Tiigi <tonistiigi@gmail.com>
+Tony Holdstock-Brown <tony@docker.com>
+Trevor Pounds <trevor.pounds@gmail.com>
+Troels Thomsen <troels@thomsen.io>
+Victor Vieux <vieux@docker.com>
+Victoria Bialas <victoria.bialas@docker.com>
+Vincent Batts <vbatts@redhat.com>
+Vincent Demeester <vincent@sbr.pm>
+Vincent Giersch <vincent.giersch@ovh.net>
+W. Trevor King <wking@tremily.us>
+weiyuan.yl <weiyuan.yl@alibaba-inc.com>
+xg.song <xg.song@venusource.com>
+xiekeyang <xiekeyang@huawei.com>
+Yann ROBERT <yann.robert@anantaplex.fr>
+yaoyao.xyy <yaoyao.xyy@alibaba-inc.com>
+yuexiao-wang <wang.yuexiao@zte.com.cn>
+yuzou <zouyu7@huawei.com>
+zhouhaibing089 <zhouhaibing089@gmail.com>
+姜继忠 <jizhong.jiangjz@alibaba-inc.com>
--- a/vendor/github.com/docker/distribution/BUILDING.md
+++ b/vendor/github.com/docker/distribution/BUILDING.md
@@ -0,0 +1,117 @@
+
+# Building the registry source
+
+## Use-case
+
+This is useful if you intend to actively work on the registry.
+
+### Alternatives
+
+Most people should use the [official Registry docker image](https://hub.docker.com/r/library/registry/).
+
+People looking for advanced operational use cases might consider rolling their own image with a custom Dockerfile inheriting `FROM registry:2`.
+
+OS X users who want to run natively can do so following [the instructions here](https://github.com/docker/docker.github.io/blob/master/registry/recipes/osx-setup-guide.md).
+
+### Gotchas
+
+You are expected to know your way around with go & git.
+
+If you are a casual user with no development experience, and no preliminary knowledge of go, building from source is probably not a good solution for you.
+
+## Build the development environment
+
+The first prerequisite of properly building distribution targets is to have a Go
+development environment setup. Please follow [How to Write Go Code](https://golang.org/doc/code.html)
+for proper setup. If done correctly, you should have a GOROOT and GOPATH set in the
+environment.
+
+If a Go development environment is setup, one can use `go get` to install the
+`registry` command from the current latest:
+
+    go get github.com/docker/distribution/cmd/registry
+
+The above will install the source repository into the `GOPATH`.
+
+Now create the directory for the registry data (this might require you to set permissions properly)
+
+    mkdir -p /var/lib/registry
+
+... or alternatively `export REGISTRY_STORAGE_FILESYSTEM_ROOTDIRECTORY=/somewhere` if you want to store data into another location.
+
+The `registry`
+binary can then be run with the following:
+
+    $ $GOPATH/bin/registry --version
+    $GOPATH/bin/registry github.com/docker/distribution v2.0.0-alpha.1+unknown
+
+> __NOTE:__ While you do not need to use `go get` to checkout the distribution
+> project, for these build instructions to work, the project must be checked
+> out in the correct location in the `GOPATH`. This should almost always be
+> `$GOPATH/src/github.com/docker/distribution`.
+
+The registry can be run with the default config using the following
+incantation:
+
+    $ $GOPATH/bin/registry serve $GOPATH/src/github.com/docker/distribution/cmd/registry/config-example.yml
+    INFO[0000] endpoint local-5003 disabled, skipping        app.id=34bbec38-a91a-494a-9a3f-b72f9010081f version=v2.0.0-alpha.1+unknown
+    INFO[0000] endpoint local-8083 disabled, skipping        app.id=34bbec38-a91a-494a-9a3f-b72f9010081f version=v2.0.0-alpha.1+unknown
+    INFO[0000] listening on :5000                            app.id=34bbec38-a91a-494a-9a3f-b72f9010081f version=v2.0.0-alpha.1+unknown
+    INFO[0000] debug server listening localhost:5001
+
+If it is working, one should see the above log messages.
+
+### Repeatable Builds
+
+For the full development experience, one should `cd` into
+`$GOPATH/src/github.com/docker/distribution`. From there, the regular `go`
+commands, such as `go test`, should work per package (please see
+[Developing](#developing) if they don't work).
+
+A `Makefile` has been provided as a convenience to support repeatable builds.
+Please install the following into `GOPATH` for it to work:
+
+    go get github.com/golang/lint/golint
+
+Once these commands are available in the `GOPATH`, run `make` to get a full
+build:
+
+    $ make
+    + clean
+    + fmt
+    + vet
+    + lint
+    + build
+    github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar
+    github.com/sirupsen/logrus
+    github.com/docker/libtrust
+    ...
+    github.com/yvasiyarov/gorelic
+    github.com/docker/distribution/registry/handlers
+    github.com/docker/distribution/cmd/registry
+    + test
+    ...
+    ok    github.com/docker/distribution/digest 7.875s
+    ok    github.com/docker/distribution/manifest 0.028s
+    ok    github.com/docker/distribution/notifications  17.322s
+    ?     github.com/docker/distribution/registry [no test files]
+    ok    github.com/docker/distribution/registry/api/v2  0.101s
+    ?     github.com/docker/distribution/registry/auth  [no test files]
+    ok    github.com/docker/distribution/registry/auth/silly  0.011s
+    ...
+    + /Users/sday/go/src/github.com/docker/distribution/bin/registry
+    + /Users/sday/go/src/github.com/docker/distribution/bin/registry-api-descriptor-template
+    + binaries
+
+The above provides a repeatable build using the contents of the vendor
+directory. This includes formatting, vetting, linting, building,
+testing and generating tagged binaries. We can verify this worked by running
+the registry binary generated in the "./bin" directory:
+
+    $ ./bin/registry -version
+    ./bin/registry github.com/docker/distribution v2.0.0-alpha.2-80-g16d8b2c.m
+
+### Optional build tags
+
+Optional [build tags](http://golang.org/pkg/go/build/) can be provided using
+the environment variable `DOCKER_BUILDTAGS`.
--- a/vendor/github.com/docker/distribution/CHANGELOG.md
+++ b/vendor/github.com/docker/distribution/CHANGELOG.md
@@ -0,0 +1,108 @@
+# Changelog
+
+## 2.6.0 (2017-01-18)
+
+#### Storage
+- S3: fixed bug in delete due to read-after-write inconsistency
+- S3: allow EC2 IAM roles to be used when authorizing region endpoints
+- S3: add Object ACL Support
+- S3: fix delete method's notion of subpaths
+- S3: use multipart upload API in `Move` method for performance
+- S3: add v2 signature signing for legacy S3 clones
+- Swift: add simple heuristic to detect incomplete DLOs during read ops
+- Swift: support different user and tenant domains
+- Swift: bulk deletes in chunks
+- Aliyun OSS: fix delete method's notion of subpaths
+- Aliyun OSS: optimize data copy after upload finishes
+- Azure: close leaking response body
+- Fix storage drivers dropping non-EOF errors when listing repositories
+- Compare path properly when listing repositories in catalog
+- Add a foreign layer URL host whitelist
+- Improve catalog enumerate runtime
+
+#### Registry
+- Export `storage.CreateOptions` in top-level package
+- Enable notifications to endpoints that use self-signed certificates
+- Properly validate multi-URL foreign layers
+- Add control over validation of URLs in pushed manifests
+- Proxy mode: fix socket leak when pull is cancelled
+- Tag service: properly handle error responses on HEAD request
+- Support for custom authentication URL in proxying registry
+- Add configuration option to disable access logging
+- Add notification filtering by target media type
+- Manifest: `References()` returns all children
+- Honor `X-Forwarded-Port` and Forwarded headers
+- Reference: Preserve tag and digest in With* functions
+- Add policy configuration for enforcing repository classes
+
+#### Client
+- Changes the client Tags `All()` method to follow links
+- Allow registry clients to connect via HTTP2
+- Better handling of OAuth errors in client
+  
+#### Spec
+- Manifest: clarify relationship between urls and foreign layers
+- Authorization: add support for repository classes
+
+#### Manifest
+- Override media type returned from `Stat()` for existing manifests
+- Add plugin mediatype to distribution manifest
+
+#### Docs
+- Document `TOOMANYREQUESTS` error code
+- Document required Let's Encrypt port
+- Improve documentation around implementation of OAuth2
+- Improve documentation for configuration
+
+#### Auth
+- Add support for registry type in scope
+- Add support for using v2 ping challenges for v1
+- Add leeway to JWT `nbf` and `exp` checking
+- htpasswd: dynamically parse htpasswd file
+- Fix missing auth headers with PATCH HTTP request when pushing to default port
+
+#### Dockerfile
+- Update to go1.7
+- Reorder Dockerfile steps for better layer caching
+
+#### Notes
+
+Documentation has moved to the documentation repository at
+`github.com/docker/docker.github.io/tree/master/registry`
+
+The registry is go 1.7 compliant, and passes newer, more restrictive `lint` and `vet` ing.
+
+
+## 2.5.0 (2016-06-14)
+
+#### Storage
+- Ensure uploads directory is cleaned after upload is committed
+- Add ability to cap concurrent operations in filesystem driver
+- S3: Add 'us-gov-west-1' to the valid region list
+- Swift: Handle ceph not returning Last-Modified header for HEAD requests
+- Add redirect middleware
+
+#### Registry
+- Add support for blobAccessController middleware
+- Add support for layers from foreign sources
+- Remove signature store
+- Add support for Let's Encrypt
+- Correct yaml key names in configuration
+
+#### Client
+- Add option to get content digest from manifest get
+
+#### Spec
+- Update the auth spec scope grammar to reflect the fact that hostnames are optionally supported
+- Clarify API documentation around catalog fetch behavior
+
+#### API
+- Support returning HTTP 429 (Too Many Requests)
+
+#### Documentation
+- Update auth documentation examples to show "expires in" as int
+
+#### Docker Image
+- Use Alpine Linux as base image
+
+
--- a/vendor/github.com/docker/distribution/CONTRIBUTING.md
+++ b/vendor/github.com/docker/distribution/CONTRIBUTING.md
@@ -0,0 +1,148 @@
+# Contributing to the registry
+
+## Before reporting an issue...
+
+### If your problem is with...
+
+ - automated builds
+ - your account on the [Docker Hub](https://hub.docker.com/)
+ - any other [Docker Hub](https://hub.docker.com/) issue
+
+Then please do not report your issue here - you should instead report it to [https://support.docker.com](https://support.docker.com)
+
+### If you...
+
+ - need help setting up your registry
+ - can't figure out something
+ - are not sure what's going on or what your problem is
+
+Then please do not open an issue here yet - you should first try one of the following support forums:
+
+ - irc: #docker-distribution on freenode
+ - mailing-list: <distribution@dockerproject.org> or https://groups.google.com/a/dockerproject.org/forum/#!forum/distribution
+
+### Reporting security issues
+
+The Docker maintainers take security seriously. If you discover a security
+issue, please bring it to their attention right away!
+
+Please **DO NOT** file a public issue, instead send your report privately to
+[security@docker.com](mailto:security@docker.com).
+
+## Reporting an issue properly
+
+By following these simple rules you will get better and faster feedback on your issue.
+
+ - search the bugtracker for an already reported issue
+
+### If you found an issue that describes your problem:
+
+ - please read other user comments first, and confirm this is the same issue: a given error condition might be indicative of different problems - you may also find a workaround in the comments
+ - please refrain from adding "same thing here" or "+1" comments
+ - you don't need to comment on an issue to get notified of updates: just hit the "subscribe" button
+ - comment if you have some new, technical and relevant information to add to the case
+ - __DO NOT__ comment on closed issues or merged PRs. If you think you have a related problem, open up a new issue and reference the PR or issue.
+
+### If you have not found an existing issue that describes your problem:
+
+ 1. create a new issue, with a succinct title that describes your issue:
+   - bad title: "It doesn't work with my docker"
+   - good title: "Private registry push fail: 400 error with E_INVALID_DIGEST"
+ 2. copy the output of:
+   - `docker version`
+   - `docker info`
+   - `docker exec <registry-container> registry --version`
+ 3. copy the command line you used to launch your Registry
+ 4. restart your docker daemon in debug mode (add `-D` to the daemon launch arguments)
+ 5. reproduce your problem and get your docker daemon logs showing the error
+ 6. if relevant, copy your registry logs that show the error
+ 7. provide any relevant detail about your specific Registry configuration (e.g., storage backend used)
+ 8. indicate if you are using an enterprise proxy, Nginx, or anything else between you and your Registry
+
+## Contributing a patch for a known bug, or a small correction
+
+You should follow the basic GitHub workflow:
+
+ 1. fork
+ 2. commit a change
+ 3. make sure the tests pass
+ 4. PR
+
+Additionally, you must [sign your commits](https://github.com/docker/docker/blob/master/CONTRIBUTING.md#sign-your-work). It's very simple:
+
+ - configure your name with git: `git config user.name "Real Name" && git config user.email mail@example.com`
+ - sign your commits using `-s`: `git commit -s -m "My commit"`
+
+Some simple rules to ensure quick merge:
+
+ - clearly point to the issue(s) you want to fix in your PR comment (e.g., `closes #12345`)
+ - prefer multiple (smaller) PRs addressing individual issues over a big one trying to address multiple issues at once
+ - if you need to amend your PR following comments, please squash instead of adding more commits
+
+## Contributing new features
+
+You are heavily encouraged to first discuss what you want to do. You can do so on the irc channel, or by opening an issue that clearly describes the use case you want to fulfill, or the problem you are trying to solve.
+
+If this is a major new feature, you should then submit a proposal that describes your technical solution and reasoning.
+If you did discuss it first, this will likely be greenlighted very fast. It's advisable to address all feedback on this proposal before starting actual work.
+
+Then you should submit your implementation, clearly linking to the issue (and possible proposal).
+
+Your PR will be reviewed by the community, then ultimately by the project maintainers, before being merged.
+
+It's mandatory to:
+
+ - interact respectfully with other community members and maintainers - more generally, you are expected to abide by the [Docker community rules](https://github.com/docker/docker/blob/master/CONTRIBUTING.md#docker-community-guidelines)
+ - address maintainers' comments and modify your submission accordingly
+ - write tests for any new code
+
+Complying to these simple rules will greatly accelerate the review process, and will ensure you have a pleasant experience in contributing code to the Registry.
+
+Have a look at a great, successful contribution: the [Swift driver PR](https://github.com/docker/distribution/pull/493)
+
+## Coding Style
+
+Unless explicitly stated, we follow all coding guidelines from the Go
+community. While some of these standards may seem arbitrary, they somehow seem
+to result in a solid, consistent codebase.
+
+It is possible that the code base does not currently comply with these
+guidelines. We are not looking for a massive PR that fixes this, since that
+goes against the spirit of the guidelines. All new contributions should make a
+best effort to clean up and make the code base better than they left it.
+Obviously, apply your best judgement. Remember, the goal here is to make the
+code base easier for humans to navigate and understand. Always keep that in
+mind when nudging others to comply.
+
+The rules:
+
+1. All code should be formatted with `gofmt -s`.
+2. All code should pass the default levels of
+   [`golint`](https://github.com/golang/lint).
+3. All code should follow the guidelines covered in [Effective
+   Go](http://golang.org/doc/effective_go.html) and [Go Code Review
+   Comments](https://github.com/golang/go/wiki/CodeReviewComments).
+4. Comment the code. Tell us the why, the history and the context.
+5. Document _all_ declarations and methods, even private ones. Declare
+   expectations, caveats and anything else that may be important. If a type
+   gets exported, having the comments already there will ensure it's ready.
+6. Variable name length should be proportional to its context and no longer.
+   `noCommaALongVariableNameLikeThisIsNotMoreClearWhenASimpleCommentWouldDo`.
+   In practice, short methods will have short variable names and globals will
+   have longer names.
+7. No underscores in package names. If you need a compound name, step back,
+   and re-examine why you need a compound name. If you still think you need a
+   compound name, lose the underscore.
+8. No utils or helpers packages. If a function is not general enough to
+   warrant its own package, it has not been written generally enough to be a
+   part of a util package. Just leave it unexported and well-documented.
+9. All tests should run with `go test` and outside tooling should not be
+   required. No, we don't need another unit testing framework. Assertion
+   packages are acceptable if they provide _real_ incremental value.
+10. Even though we call these "rules" above, they are actually just
+    guidelines. Since you've read all the rules, you now know that.
+
+If you are having trouble getting into the mood of idiomatic Go, we recommend
+reading through [Effective Go](http://golang.org/doc/effective_go.html). The
+[Go Blog](http://blog.golang.org/) is also a great resource. Drinking the
+kool-aid is a lot easier than going thirsty.
--- a/vendor/github.com/docker/distribution/Dockerfile
+++ b/vendor/github.com/docker/distribution/Dockerfile
@@ -0,0 +1,21 @@
+FROM golang:1.8-alpine
+
+ENV DISTRIBUTION_DIR /go/src/github.com/docker/distribution
+ENV DOCKER_BUILDTAGS include_oss include_gcs
+
+ARG GOOS=linux
+ARG GOARCH=amd64
+
+RUN set -ex \
+    && apk add --no-cache make git
+
+WORKDIR $DISTRIBUTION_DIR
+COPY . $DISTRIBUTION_DIR
+COPY cmd/registry/config-dev.yml /etc/docker/registry/config.yml
+
+RUN make PREFIX=/go clean binaries
+
+VOLUME ["/var/lib/registry"]
+EXPOSE 5000
+ENTRYPOINT ["registry"]
+CMD ["serve", "/etc/docker/registry/config.yml"]
--- a/vendor/github.com/docker/distribution/LICENSE
+++ b/vendor/github.com/docker/distribution/LICENSE
@@ -0,0 +1,202 @@
+Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+      any Contribution intentionally submitted for inclusion in the Work
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+
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+
+      To apply the Apache License to your work, attach the following
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+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
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+   See the License for the specific language governing permissions and
+   limitations under the License.
+
--- a/vendor/github.com/docker/distribution/MAINTAINERS
+++ b/vendor/github.com/docker/distribution/MAINTAINERS
@@ -0,0 +1,58 @@
+# Distribution maintainers file
+#
+# This file describes who runs the docker/distribution project and how.
+# This is a living document - if you see something out of date or missing, speak up!
+#
+# It is structured to be consumable by both humans and programs.
+# To extract its contents programmatically, use any TOML-compliant parser.
+#
+# This file is compiled into the MAINTAINERS file in docker/opensource.
+#
+[Org]
+	[Org."Core maintainers"]
+		people = [
+			"aaronlehmann",
+			"dmcgowan",
+			"dmp42",
+			"richardscothern",
+			"shykes",
+			"stevvooe",
+		]
+
+[people]
+
+# A reference list of all people associated with the project.
+# All other sections should refer to people by their canonical key
+# in the people section.
+
+	# ADD YOURSELF HERE IN ALPHABETICAL ORDER
+
+	[people.aaronlehmann]
+	Name = "Aaron Lehmann"
+	Email = "aaron.lehmann@docker.com"
+	GitHub = "aaronlehmann"
+
+	[people.dmcgowan]
+	Name = "Derek McGowan"
+	Email = "derek@mcgstyle.net"
+	GitHub = "dmcgowan"
+
+	[people.dmp42]
+	Name = "Olivier Gambier"
+	Email = "olivier@docker.com"
+	GitHub = "dmp42"
+
+	[people.richardscothern]
+	Name = "Richard Scothern"
+	Email = "richard.scothern@gmail.com"
+	GitHub = "richardscothern"
+
+	[people.shykes]
+	Name = "Solomon Hykes"
+	Email = "solomon@docker.com"
+	GitHub = "shykes"
+
+	[people.stevvooe]
+	Name = "Stephen Day"
+	Email = "stephen.day@docker.com"
+	GitHub = "stevvooe"
--- a/vendor/github.com/docker/distribution/Makefile
+++ b/vendor/github.com/docker/distribution/Makefile
@@ -0,0 +1,99 @@
+# Set an output prefix, which is the local directory if not specified
+PREFIX?=$(shell pwd)
+
+
+# Used to populate version variable in main package.
+VERSION=$(shell git describe --match 'v[0-9]*' --dirty='.m' --always)
+
+# Allow turning off function inlining and variable registerization
+ifeq (${DISABLE_OPTIMIZATION},true)
+	GO_GCFLAGS=-gcflags "-N -l"
+	VERSION:="$(VERSION)-noopt"
+endif
+
+GO_LDFLAGS=-ldflags "-X `go list ./version`.Version=$(VERSION)"
+
+.PHONY: all build binaries clean dep-restore dep-save dep-validate fmt lint test test-full vet
+.DEFAULT: all
+all: fmt vet lint build test binaries
+
+AUTHORS: .mailmap .git/HEAD
+	 git log --format='%aN <%aE>' | sort -fu > $@
+
+# This only needs to be generated by hand when cutting full releases.
+version/version.go:
+	./version/version.sh > $@
+
+# Required for go 1.5 to build
+GO15VENDOREXPERIMENT := 1
+
+# Go files
+GOFILES=$(shell find . -type f -name '*.go')
+
+# Package list
+PKGS=$(shell go list -tags "${DOCKER_BUILDTAGS}" ./... | grep -v ^github.com/docker/distribution/vendor/)
+
+# Resolving binary dependencies for specific targets
+GOLINT=$(shell which golint || echo '')
+VNDR=$(shell which vndr || echo '')
+
+${PREFIX}/bin/registry: $(GOFILES)
+	@echo "+ $@"
+	@go build -tags "${DOCKER_BUILDTAGS}" -o $@ ${GO_LDFLAGS}  ${GO_GCFLAGS} ./cmd/registry
+
+${PREFIX}/bin/digest:  $(GOFILES)
+	@echo "+ $@"
+	@go build -tags "${DOCKER_BUILDTAGS}" -o $@ ${GO_LDFLAGS}  ${GO_GCFLAGS} ./cmd/digest
+
+${PREFIX}/bin/registry-api-descriptor-template: $(GOFILES)
+	@echo "+ $@"
+	@go build -o $@ ${GO_LDFLAGS} ${GO_GCFLAGS} ./cmd/registry-api-descriptor-template
+
+docs/spec/api.md: docs/spec/api.md.tmpl ${PREFIX}/bin/registry-api-descriptor-template
+	./bin/registry-api-descriptor-template $< > $@
+
+vet:
+	@echo "+ $@"
+	@go vet -tags "${DOCKER_BUILDTAGS}" $(PKGS)
+
+fmt:
+	@echo "+ $@"
+	@test -z "$$(gofmt -s -l . 2>&1 | grep -v ^vendor/ | tee /dev/stderr)" || \
+		(echo >&2 "+ please format Go code with 'gofmt -s'" && false)
+
+lint:
+	@echo "+ $@"
+	$(if $(GOLINT), , \
+		$(error Please install golint: `go get -u github.com/golang/lint/golint`))
+	@test -z "$$($(GOLINT) ./... 2>&1 | grep -v ^vendor/ | tee /dev/stderr)"
+
+build:
+	@echo "+ $@"
+	@go build -tags "${DOCKER_BUILDTAGS}" -v ${GO_LDFLAGS} $(PKGS)
+
+test:
+	@echo "+ $@"
+	@go test -test.short -tags "${DOCKER_BUILDTAGS}" $(PKGS)
+
+test-full:
+	@echo "+ $@"
+	@go test -tags "${DOCKER_BUILDTAGS}" $(PKGS)
+
+binaries: ${PREFIX}/bin/registry ${PREFIX}/bin/digest ${PREFIX}/bin/registry-api-descriptor-template
+	@echo "+ $@"
+
+clean:
+	@echo "+ $@"
+	@rm -rf "${PREFIX}/bin/registry" "${PREFIX}/bin/digest" "${PREFIX}/bin/registry-api-descriptor-template"
+
+dep-validate:
+	@echo "+ $@"
+	$(if $(VNDR), , \
+		$(error Please install vndr: go get github.com/lk4d4/vndr))
+	@rm -Rf .vendor.bak
+	@mv vendor .vendor.bak
+	@$(VNDR)
+	@test -z "$$(diff -r vendor .vendor.bak 2>&1 | tee /dev/stderr)" || \
+		(echo >&2 "+ inconsistent dependencies! what you have in vendor.conf does not match with what you have in vendor" && false)
+	@rm -Rf vendor
+	@mv .vendor.bak vendor
--- a/vendor/github.com/docker/distribution/README.md
+++ b/vendor/github.com/docker/distribution/README.md
@@ -0,0 +1,130 @@
+# Distribution
+
+The Docker toolset to pack, ship, store, and deliver content.
+
+This repository's main product is the Docker Registry 2.0 implementation
+for storing and distributing Docker images. It supersedes the
+[docker/docker-registry](https://github.com/docker/docker-registry)
+project with a new API design, focused around security and performance.
+
+<img src="https://www.docker.com/sites/default/files/oyster-registry-3.png" width=200px/>
+
+[![Circle CI](https://circleci.com/gh/docker/distribution/tree/master.svg?style=svg)](https://circleci.com/gh/docker/distribution/tree/master)
+[![GoDoc](https://godoc.org/github.com/docker/distribution?status.svg)](https://godoc.org/github.com/docker/distribution)
+
+This repository contains the following components:
+
+|**Component**       |Description                                                                                                                                                                                         |
+|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| **registry**       | An implementation of the [Docker Registry HTTP API V2](docs/spec/api.md) for use with docker 1.6+.                                                                                                  |
+| **libraries**      | A rich set of libraries for interacting with distribution components. Please see [godoc](https://godoc.org/github.com/docker/distribution) for details. **Note**: These libraries are **unstable**. |
+| **specifications** | _Distribution_ related specifications are available in [docs/spec](docs/spec)                                                                                                                        |
+| **documentation**  | Docker's full documentation set is available at [docs.docker.com](https://docs.docker.com). This repository [contains the subset](docs/) related just to the registry.                                                                                                                                          |
+
+### How does this integrate with Docker engine?
+
+This project should provide an implementation to a V2 API for use in the [Docker
+core project](https://github.com/docker/docker). The API should be embeddable
+and simplify the process of securely pulling and pushing content from `docker`
+daemons.
+
+### What are the long term goals of the Distribution project?
+
+The _Distribution_ project has the further long term goal of providing a
+secure tool chain for distributing content. The specifications, APIs and tools
+should be as useful with Docker as they are without.
+
+Our goal is to design a professional grade and extensible content distribution
+system that allow users to:
+
+* Enjoy an efficient, secured and reliable way to store, manage, package and
+  exchange content
+* Hack/roll their own on top of healthy open-source components
+* Implement their own home made solution through good specs, and solid
+  extensions mechanism.
+
+## More about Registry 2.0
+
+The new registry implementation provides the following benefits:
+
+- faster push and pull
+- new, more efficient implementation
+- simplified deployment
+- pluggable storage backend
+- webhook notifications
+
+For information on upcoming functionality, please see [ROADMAP.md](ROADMAP.md).
+
+### Who needs to deploy a registry?
+
+By default, Docker users pull images from Docker's public registry instance.
+[Installing Docker](https://docs.docker.com/engine/installation/) gives users this
+ability. Users can also push images to a repository on Docker's public registry,
+if they have a [Docker Hub](https://hub.docker.com/) account.
+
+For some users and even companies, this default behavior is sufficient. For
+others, it is not.
+
+For example, users with their own software products may want to maintain a
+registry for private, company images. Also, you may wish to deploy your own
+image repository for images used to test or in continuous integration. For these
+use cases and others, [deploying your own registry instance](https://github.com/docker/docker.github.io/blob/master/registry/deploying.md)
+may be the better choice.
+
+### Migration to Registry 2.0
+
+For those who have previously deployed their own registry based on the Registry
+1.0 implementation and wish to deploy a Registry 2.0 while retaining images,
+data migration is required. A tool to assist with migration efforts has been
+created. For more information see [docker/migrator](https://github.com/docker/migrator).
+
+## Contribute
+
+Please see [CONTRIBUTING.md](CONTRIBUTING.md) for details on how to contribute
+issues, fixes, and patches to this project. If you are contributing code, see
+the instructions for [building a development environment](BUILDING.md).
+
+## Support
+
+If any issues are encountered while using the _Distribution_ project, several
+avenues are available for support:
+
+<table>
+<tr>
+	<th align="left">
+	IRC
+	</th>
+	<td>
+	#docker-distribution on FreeNode
+	</td>
+</tr>
+<tr>
+	<th align="left">
+	Issue Tracker
+	</th>
+	<td>
+	github.com/docker/distribution/issues
+	</td>
+</tr>
+<tr>
+	<th align="left">
+	Google Groups
+	</th>
+	<td>
+	https://groups.google.com/a/dockerproject.org/forum/#!forum/distribution
+	</td>
+</tr>
+<tr>
+	<th align="left">
+	Mailing List
+	</th>
+	<td>
+	docker@dockerproject.org
+	</td>
+</tr>
+</table>
+
+
+## License
+
+This project is distributed under [Apache License, Version 2.0](LICENSE).
--- a/vendor/github.com/docker/distribution/RELEASE-CHECKLIST.md
+++ b/vendor/github.com/docker/distribution/RELEASE-CHECKLIST.md
@@ -0,0 +1,44 @@
+## Registry Release Checklist
+
+10. Compile release notes detailing features and since the last release.
+
+  Update the `CHANGELOG.md` file and create a PR to master with the updates.
+Once that PR has been approved by maintainers the change may be cherry-picked
+to the release branch (new release branches may be forked from this commit).
+
+20. Update the version file: `https://github.com/docker/distribution/blob/master/version/version.go`
+
+30. Update the `MAINTAINERS` (if necessary), `AUTHORS` and `.mailmap` files.
+
+```
+make AUTHORS
+```
+
+40. Create a signed tag.
+
+   Distribution uses semantic versioning.  Tags are of the format
+`vx.y.z[-rcn]`. You will need PGP installed and a PGP key which has been added
+to your Github account. The comment for the tag should include the release
+notes, use previous tags as a guide for formatting consistently. Run
+`git tag -s vx.y.z[-rcn]` to create tag and `git -v vx.y.z[-rcn]` to verify tag,
+check comment and correct commit hash.
+
+50. Push the signed tag
+
+60. Create a new [release](https://github.com/docker/distribution/releases).  In the case of a release candidate, tick the `pre-release` checkbox. 
+
+70. Update the registry binary in [distribution library image repo](https://github.com/docker/distribution-library-image) by running the update script and  opening a pull request.
+
+80. Update the official image.  Add the new version in the [official images repo](https://github.com/docker-library/official-images) by appending a new version to the `registry/registry` file with the git hash pointed to by the signed tag.  Update the major version to point to the latest version and the minor version to point to new patch release if necessary.
+e.g. to release `2.3.1`
+
+   `2.3.1 (new)`
+
+   `2.3.0 -> 2.3.0` can be removed
+
+   `2 -> 2.3.1`
+
+   `2.3 -> 2.3.1`
+
+90. Build a new distribution/registry image on [Docker hub](https://hub.docker.com/u/distribution/dashboard) by adding a new automated build with the new tag and re-building the images.
+
--- a/vendor/github.com/docker/distribution/ROADMAP.md
+++ b/vendor/github.com/docker/distribution/ROADMAP.md
@@ -0,0 +1,267 @@
+# Roadmap
+
+The Distribution Project consists of several components, some of which are
+still being defined. This document defines the high-level goals of the
+project, identifies the current components, and defines the release-
+relationship to the Docker Platform.
+
+* [Distribution Goals](#distribution-goals)
+* [Distribution Components](#distribution-components)
+* [Project Planning](#project-planning): release-relationship to the Docker Platform.
+
+This road map is a living document, providing an overview of the goals and
+considerations made in respect of the future of the project.
+
+## Distribution Goals
+
+- Replace the existing [docker registry](github.com/docker/docker-registry)
+  implementation as the primary implementation.
+- Replace the existing push and pull code in the docker engine with the
+  distribution package.
+- Define a strong data model for distributing docker images
+- Provide a flexible distribution tool kit for use in the docker platform
+- Unlock new distribution models
+
+## Distribution Components
+
+Components of the Distribution Project are managed via github [milestones](https://github.com/docker/distribution/milestones). Upcoming
+features and bugfixes for a component will be added to the relevant milestone. If a feature or
+bugfix is not part of a milestone, it is currently unscheduled for
+implementation. 
+
+* [Registry](#registry)
+* [Distribution Package](#distribution-package)
+
+***
+
+### Registry
+
+The new Docker registry is the main portion of the distribution repository.
+Registry 2.0 is the first release of the next-generation registry. This was
+primarily focused on implementing the [new registry
+API](https://github.com/docker/distribution/blob/master/docs/spec/api.md),
+with a focus on security and performance. 
+
+Following from the Distribution project goals above, we have a set of goals
+for registry v2 that we would like to follow in the design. New features
+should be compared against these goals.
+
+#### Data Storage and Distribution First
+
+The registry's first goal is to provide a reliable, consistent storage
+location for Docker images. The registry should only provide the minimal
+amount of indexing required to fetch image data and no more.
+
+This means we should be selective in new features and API additions, including
+those that may require expensive, ever growing indexes. Requests should be
+servable in "constant time".
+
+#### Content Addressability
+
+All data objects used in the registry API should be content addressable.
+Content identifiers should be secure and verifiable. This provides a secure,
+reliable base from which to build more advanced content distribution systems.
+
+#### Content Agnostic
+
+In the past, changes to the image format would require large changes in Docker
+and the Registry. By decoupling the distribution and image format, we can
+allow the formats to progress without having to coordinate between the two.
+This means that we should be focused on decoupling Docker from the registry
+just as much as decoupling the registry from Docker. Such an approach will
+allow us to unlock new distribution models that haven't been possible before.
+
+We can take this further by saying that the new registry should be content
+agnostic. The registry provides a model of names, tags, manifests and content
+addresses and that model can be used to work with content.
+
+#### Simplicity
+
+The new registry should be closer to a microservice component than its
+predecessor. This means it should have a narrower API and a low number of
+service dependencies. It should be easy to deploy.
+
+This means that other solutions should be explored before changing the API or
+adding extra dependencies. If functionality is required, can it be added as an
+extension or companion service.
+
+#### Extensibility
+
+The registry should provide extension points to add functionality. By keeping
+the scope narrow, but providing the ability to add functionality.
+
+Features like search, indexing, synchronization and registry explorers fall
+into this category. No such feature should be added unless we've found it
+impossible to do through an extension.
+
+#### Active Feature Discussions
+
+The following are feature discussions that are currently active.
+
+If you don't see your favorite, unimplemented feature, feel free to contact us
+via IRC or the mailing list and we can talk about adding it. The goal here is
+to make sure that new features go through a rigid design process before
+landing in the registry.
+
+##### Proxying to other Registries
+
+A _pull-through caching_ mode exists for the registry, but is restricted from 
+within the docker client to only mirror the official Docker Hub.  This functionality
+can be expanded when image provenance has been specified and implemented in the 
+distribution project.
+
+##### Metadata storage
+
+Metadata for the registry is currently stored with the manifest and layer data on
+the storage backend.  While this is a big win for simplicity and reliably maintaining
+state, it comes with the cost of consistency and high latency.  The mutable registry
+metadata operations should be abstracted behind an API which will allow ACID compliant
+storage systems to handle metadata.
+
+##### Peer to Peer transfer
+
+Discussion has started here: https://docs.google.com/document/d/1rYDpSpJiQWmCQy8Cuiaa3NH-Co33oK_SC9HeXYo87QA/edit
+
+##### Indexing, Search and Discovery
+
+The original registry provided some implementation of search for use with
+private registries. Support has been elided from V2 since we'd like to both
+decouple search functionality from the registry. The makes the registry
+simpler to deploy, especially in use cases where search is not needed, and
+let's us decouple the image format from the registry.
+
+There are explorations into using the catalog API and notification system to
+build external indexes. The current line of thought is that we will define a
+common search API to index and query docker images. Such a system could be run
+as a companion to a registry or set of registries to power discovery.
+
+The main issue with search and discovery is that there are so many ways to
+accomplish it. There are two aspects to this project. The first is deciding on
+how it will be done, including an API definition that can work with changing
+data formats. The second is the process of integrating with `docker search`.
+We expect that someone attempts to address the problem with the existing tools
+and propose it as a standard search API or uses it to inform a standardization
+process. Once this has been explored, we integrate with the docker client.
+
+Please see the following for more detail:
+
+- https://github.com/docker/distribution/issues/206
+
+##### Deletes
+
+> __NOTE:__ Deletes are a much asked for feature. Before requesting this
+feature or participating in discussion, we ask that you read this section in
+full and understand the problems behind deletes.
+
+While, at first glance, implementing deleting seems simple, there are a number
+mitigating factors that make many solutions not ideal or even pathological in
+the context of a registry. The following paragraph discuss the background and
+approaches that could be applied to arrive at a solution.
+
+The goal of deletes in any system is to remove unused or unneeded data. Only
+data requested for deletion should be removed and no other data. Removing
+unintended data is worse than _not_ removing data that was requested for
+removal but ideally, both are supported. Generally, according to this rule, we
+err on holding data longer than needed, ensuring that it is only removed when
+we can be certain that it can be removed. With the current behavior, we opt to
+hold onto the data forever, ensuring that data cannot be incorrectly removed.
+
+To understand the problems with implementing deletes, one must understand the
+data model. All registry data is stored in a filesystem layout, implemented on
+a "storage driver", effectively a _virtual file system_ (VFS). The storage
+system must assume that this VFS layer will be eventually consistent and has
+poor read- after-write consistency, since this is the lower common denominator
+among the storage drivers. This is mitigated by writing values in reverse-
+dependent order, but makes wider transactional operations unsafe.
+
+Layered on the VFS model is a content-addressable _directed, acyclic graph_
+(DAG) made up of blobs. Manifests reference layers. Tags reference manifests.
+Since the same data can be referenced by multiple manifests, we only store
+data once, even if it is in different repositories. Thus, we have a set of
+blobs, referenced by tags and manifests. If we want to delete a blob we need
+to be certain that it is no longer referenced by another manifest or tag. When
+we delete a manifest, we also can try to delete the referenced blobs. Deciding
+whether or not a blob has an active reference is the crux of the problem.
+
+Conceptually, deleting a manifest and its resources is quite simple. Just find
+all the manifests, enumerate the referenced blobs and delete the blobs not in
+that set. An astute observer will recognize this as a garbage collection
+problem. As with garbage collection in programming languages, this is very
+simple when one always has a consistent view. When one adds parallelism and an
+inconsistent view of data, it becomes very challenging.
+
+A simple example can demonstrate this. Let's say we are deleting a manifest
+_A_ in one process. We scan the manifest and decide that all the blobs are
+ready for deletion. Concurrently, we have another process accepting a new
+manifest _B_ referencing one or more blobs from the manifest _A_. Manifest _B_
+is accepted and all the blobs are considered present, so the operation
+proceeds. The original process then deletes the referenced blobs, assuming
+they were unreferenced. The manifest _B_, which we thought had all of its data
+present, can no longer be served by the registry, since the dependent data has
+been deleted.
+
+Deleting data from the registry safely requires some way to coordinate this
+operation. The following approaches are being considered:
+
+- _Reference Counting_ - Maintain a count of references to each blob. This is
+  challenging for a number of reasons: 1. maintaining a consistent consensus
+  of reference counts across a set of Registries and 2. Building the initial
+  list of reference counts for an existing registry. These challenges can be
+  met with a consensus protocol like Paxos or Raft in the first case and a
+  necessary but simple scan in the second..
+- _Lock the World GC_ - Halt all writes to the data store. Walk the data store
+  and find all blob references. Delete all unreferenced blobs. This approach
+  is very simple but requires disabling writes for a period of time while the
+  service reads all data. This is slow and expensive but very accurate and
+  effective.
+- _Generational GC_ - Do something similar to above but instead of blocking
+  writes, writes are sent to another storage backend while reads are broadcast
+  to the new and old backends. GC is then performed on the read-only portion.
+  Because writes land in the new backend, the data in the read-only section
+  can be safely deleted. The main drawbacks of this approach are complexity
+  and coordination.
+- _Centralized Oracle_ - Using a centralized, transactional database, we can
+  know exactly which data is referenced at any given time. This avoids
+  coordination problem by managing this data in a single location. We trade
+  off metadata scalability for simplicity and performance. This is a very good
+  option for most registry deployments. This would create a bottleneck for
+  registry metadata. However, metadata is generally not the main bottleneck
+  when serving images.
+
+Please let us know if other solutions exist that we have yet to enumerate.
+Note that for any approach, implementation is a massive consideration. For
+example, a mark-sweep based solution may seem simple but the amount of work in
+coordination offset the extra work it might take to build a _Centralized
+Oracle_. We'll accept proposals for any solution but please coordinate with us
+before dropping code.
+
+At this time, we have traded off simplicity and ease of deployment for disk
+space. Simplicity and ease of deployment tend to reduce developer involvement,
+which is currently the most expensive resource in software engineering. Taking
+on any solution for deletes will greatly effect these factors, trading off
+very cheap disk space for a complex deployment and operational story.
+
+Please see the following issues for more detail:
+
+- https://github.com/docker/distribution/issues/422
+- https://github.com/docker/distribution/issues/461
+- https://github.com/docker/distribution/issues/462
+
+### Distribution Package 
+
+At its core, the Distribution Project is a set of Go packages that make up
+Distribution Components. At this time, most of these packages make up the
+Registry implementation. 
+
+The package itself is considered unstable. If you're using it, please take care to vendor the dependent version. 
+
+For feature additions, please see the Registry section. In the future, we may break out a
+separate Roadmap for distribution-specific features that apply to more than
+just the registry.
+
+***
+
+### Project Planning
+
+An [Open-Source Planning Process](https://github.com/docker/distribution/wiki/Open-Source-Planning-Process) is used to define the Roadmap. [Project Pages](https://github.com/docker/distribution/wiki) define the goals for each Milestone and identify current progress.
+
--- a/vendor/github.com/docker/distribution/circle.yml
+++ b/vendor/github.com/docker/distribution/circle.yml
@@ -0,0 +1,94 @@
+# Pony-up!
+machine:
+  pre:
+  # Install gvm
+    - bash < <(curl -s -S -L https://raw.githubusercontent.com/moovweb/gvm/1.0.22/binscripts/gvm-installer)
+  # Install codecov for coverage
+    - pip install --user codecov
+
+  post:
+  # go
+    - gvm install go1.8 --prefer-binary --name=stable
+
+  environment:
+  # Convenient shortcuts to "common" locations
+    CHECKOUT: /home/ubuntu/$CIRCLE_PROJECT_REPONAME
+    BASE_DIR: src/github.com/$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME
+  # Trick circle brainflat "no absolute path" behavior
+    BASE_STABLE: ../../../$HOME/.gvm/pkgsets/stable/global/$BASE_DIR
+    DOCKER_BUILDTAGS: "include_oss include_gcs"
+  # Workaround Circle parsing dumb bugs and/or YAML wonkyness
+    CIRCLE_PAIN: "mode: set"
+
+  hosts:
+  # Not used yet
+    fancy: 127.0.0.1
+
+dependencies:
+  pre:
+  # Copy the code to the gopath of all go versions
+    - >
+      gvm use stable &&
+      mkdir -p "$(dirname $BASE_STABLE)" &&
+      cp -R "$CHECKOUT" "$BASE_STABLE"
+
+  override:
+  # Install dependencies for every copied clone/go version
+    - gvm use stable && go get github.com/lk4d4/vndr:
+        pwd: $BASE_STABLE
+
+  post:
+  # For the stable go version, additionally install linting tools
+    - >
+      gvm use stable &&
+      go get github.com/axw/gocov/gocov github.com/golang/lint/golint
+
+test:
+  pre:
+  # Output the go versions we are going to test
+    # - gvm use old && go version
+    - gvm use stable && go version
+
+  # Ensure validation of dependencies
+    - git fetch origin:
+        pwd: $BASE_STABLE
+    - gvm use stable && if test -n "`git diff --stat=1000 origin/master | grep -E \"^[[:space:]]*vendor\"`"; then make dep-validate; fi:
+        pwd: $BASE_STABLE
+
+  # First thing: build everything. This will catch compile errors, and it's
+  # also necessary for go vet to work properly (see #807).
+    - gvm use stable && go install $(go list ./... | grep -v "/vendor/"):
+        pwd: $BASE_STABLE
+
+  # FMT
+    - gvm use stable && make fmt:
+        pwd: $BASE_STABLE
+
+   # VET
+    - gvm use stable && make vet:
+        pwd: $BASE_STABLE
+
+  # LINT
+    - gvm use stable && make lint:
+        pwd: $BASE_STABLE
+
+  override:
+  # Test stable, and report
+     - gvm use stable; export ROOT_PACKAGE=$(go list .); go list -tags "$DOCKER_BUILDTAGS" ./... | grep -v "/vendor/" | xargs -L 1 -I{} bash -c 'export PACKAGE={}; go test -tags "$DOCKER_BUILDTAGS" -test.short -coverprofile=$GOPATH/src/$PACKAGE/coverage.out -coverpkg=$(./coverpkg.sh $PACKAGE $ROOT_PACKAGE) $PACKAGE':
+         timeout: 1000
+         pwd: $BASE_STABLE
+
+  # Test stable with race
+     - gvm use stable; export ROOT_PACKAGE=$(go list .); go list -tags "$DOCKER_BUILDTAGS" ./... | grep -v "/vendor/" | grep -v "registry/handlers" | grep -v "registry/storage/driver" | xargs -L 1 -I{} bash -c 'export PACKAGE={}; go test -race -tags "$DOCKER_BUILDTAGS" -test.short $PACKAGE':
+         timeout: 1000
+         pwd: $BASE_STABLE
+  post:
+  # Report to codecov
+    - bash <(curl -s https://codecov.io/bash):
+        pwd: $BASE_STABLE
+
+  ## Notes
+  # Do we want these as well?
+  # - go get code.google.com/p/go.tools/cmd/goimports
+  # - test -z "$(goimports -l -w ./... | tee /dev/stderr)"
+  # http://labix.org/gocheck
--- a/vendor/github.com/docker/distribution/coverpkg.sh
+++ b/vendor/github.com/docker/distribution/coverpkg.sh
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+# Given a subpackage and the containing package, figures out which packages
+# need to be passed to `go test -coverpkg`:  this includes all of the
+# subpackage's dependencies within the containing package, as well as the
+# subpackage itself.
+DEPENDENCIES="$(go list -f $'{{range $f := .Deps}}{{$f}}\n{{end}}' ${1} | grep ${2} | grep -v github.com/docker/distribution/vendor)"
+echo "${1} ${DEPENDENCIES}" | xargs echo -n | tr ' ' ','
--- a/vendor/github.com/docker/distribution/digestset/set.go
+++ b/vendor/github.com/docker/distribution/digestset/set.go
@@ -0,0 +1,247 @@
+package digestset
+
+import (
+	"errors"
+	"sort"
+	"strings"
+	"sync"
+
+	digest "github.com/opencontainers/go-digest"
+)
+
+var (
+	// ErrDigestNotFound is used when a matching digest
+	// could not be found in a set.
+	ErrDigestNotFound = errors.New("digest not found")
+
+	// ErrDigestAmbiguous is used when multiple digests
+	// are found in a set. None of the matching digests
+	// should be considered valid matches.
+	ErrDigestAmbiguous = errors.New("ambiguous digest string")
+)
+
+// Set is used to hold a unique set of digests which
+// may be easily referenced by easily  referenced by a string
+// representation of the digest as well as short representation.
+// The uniqueness of the short representation is based on other
+// digests in the set. If digests are omitted from this set,
+// collisions in a larger set may not be detected, therefore it
+// is important to always do short representation lookups on
+// the complete set of digests. To mitigate collisions, an
+// appropriately long short code should be used.
+type Set struct {
+	mutex   sync.RWMutex
+	entries digestEntries
+}
+
+// NewSet creates an empty set of digests
+// which may have digests added.
+func NewSet() *Set {
+	return &Set{
+		entries: digestEntries{},
+	}
+}
+
+// checkShortMatch checks whether two digests match as either whole
+// values or short values. This function does not test equality,
+// rather whether the second value could match against the first
+// value.
+func checkShortMatch(alg digest.Algorithm, hex, shortAlg, shortHex string) bool {
+	if len(hex) == len(shortHex) {
+		if hex != shortHex {
+			return false
+		}
+		if len(shortAlg) > 0 && string(alg) != shortAlg {
+			return false
+		}
+	} else if !strings.HasPrefix(hex, shortHex) {
+		return false
+	} else if len(shortAlg) > 0 && string(alg) != shortAlg {
+		return false
+	}
+	return true
+}
+
+// Lookup looks for a digest matching the given string representation.
+// If no digests could be found ErrDigestNotFound will be returned
+// with an empty digest value. If multiple matches are found
+// ErrDigestAmbiguous will be returned with an empty digest value.
+func (dst *Set) Lookup(d string) (digest.Digest, error) {
+	dst.mutex.RLock()
+	defer dst.mutex.RUnlock()
+	if len(dst.entries) == 0 {
+		return "", ErrDigestNotFound
+	}
+	var (
+		searchFunc func(int) bool
+		alg        digest.Algorithm
+		hex        string
+	)
+	dgst, err := digest.Parse(d)
+	if err == digest.ErrDigestInvalidFormat {
+		hex = d
+		searchFunc = func(i int) bool {
+			return dst.entries[i].val >= d
+		}
+	} else {
+		hex = dgst.Hex()
+		alg = dgst.Algorithm()
+		searchFunc = func(i int) bool {
+			if dst.entries[i].val == hex {
+				return dst.entries[i].alg >= alg
+			}
+			return dst.entries[i].val >= hex
+		}
+	}
+	idx := sort.Search(len(dst.entries), searchFunc)
+	if idx == len(dst.entries) || !checkShortMatch(dst.entries[idx].alg, dst.entries[idx].val, string(alg), hex) {
+		return "", ErrDigestNotFound
+	}
+	if dst.entries[idx].alg == alg && dst.entries[idx].val == hex {
+		return dst.entries[idx].digest, nil
+	}
+	if idx+1 < len(dst.entries) && checkShortMatch(dst.entries[idx+1].alg, dst.entries[idx+1].val, string(alg), hex) {
+		return "", ErrDigestAmbiguous
+	}
+
+	return dst.entries[idx].digest, nil
+}
+
+// Add adds the given digest to the set. An error will be returned
+// if the given digest is invalid. If the digest already exists in the
+// set, this operation will be a no-op.
+func (dst *Set) Add(d digest.Digest) error {
+	if err := d.Validate(); err != nil {
+		return err
+	}
+	dst.mutex.Lock()
+	defer dst.mutex.Unlock()
+	entry := &digestEntry{alg: d.Algorithm(), val: d.Hex(), digest: d}
+	searchFunc := func(i int) bool {
+		if dst.entries[i].val == entry.val {
+			return dst.entries[i].alg >= entry.alg
+		}
+		return dst.entries[i].val >= entry.val
+	}
+	idx := sort.Search(len(dst.entries), searchFunc)
+	if idx == len(dst.entries) {
+		dst.entries = append(dst.entries, entry)
+		return nil
+	} else if dst.entries[idx].digest == d {
+		return nil
+	}
+
+	entries := append(dst.entries, nil)
+	copy(entries[idx+1:], entries[idx:len(entries)-1])
+	entries[idx] = entry
+	dst.entries = entries
+	return nil
+}
+
+// Remove removes the given digest from the set. An err will be
+// returned if the given digest is invalid. If the digest does
+// not exist in the set, this operation will be a no-op.
+func (dst *Set) Remove(d digest.Digest) error {
+	if err := d.Validate(); err != nil {
+		return err
+	}
+	dst.mutex.Lock()
+	defer dst.mutex.Unlock()
+	entry := &digestEntry{alg: d.Algorithm(), val: d.Hex(), digest: d}
+	searchFunc := func(i int) bool {
+		if dst.entries[i].val == entry.val {
+			return dst.entries[i].alg >= entry.alg
+		}
+		return dst.entries[i].val >= entry.val
+	}
+	idx := sort.Search(len(dst.entries), searchFunc)
+	// Not found if idx is after or value at idx is not digest
+	if idx == len(dst.entries) || dst.entries[idx].digest != d {
+		return nil
+	}
+
+	entries := dst.entries
+	copy(entries[idx:], entries[idx+1:])
+	entries = entries[:len(entries)-1]
+	dst.entries = entries
+
+	return nil
+}
+
+// All returns all the digests in the set
+func (dst *Set) All() []digest.Digest {
+	dst.mutex.RLock()
+	defer dst.mutex.RUnlock()
+	retValues := make([]digest.Digest, len(dst.entries))
+	for i := range dst.entries {
+		retValues[i] = dst.entries[i].digest
+	}
+
+	return retValues
+}
+
+// ShortCodeTable returns a map of Digest to unique short codes. The
+// length represents the minimum value, the maximum length may be the
+// entire value of digest if uniqueness cannot be achieved without the
+// full value. This function will attempt to make short codes as short
+// as possible to be unique.
+func ShortCodeTable(dst *Set, length int) map[digest.Digest]string {
+	dst.mutex.RLock()
+	defer dst.mutex.RUnlock()
+	m := make(map[digest.Digest]string, len(dst.entries))
+	l := length
+	resetIdx := 0
+	for i := 0; i < len(dst.entries); i++ {
+		var short string
+		extended := true
+		for extended {
+			extended = false
+			if len(dst.entries[i].val) <= l {
+				short = dst.entries[i].digest.String()
+			} else {
+				short = dst.entries[i].val[:l]
+				for j := i + 1; j < len(dst.entries); j++ {
+					if checkShortMatch(dst.entries[j].alg, dst.entries[j].val, "", short) {
+						if j > resetIdx {
+							resetIdx = j
+						}
+						extended = true
+					} else {
+						break
+					}
+				}
+				if extended {
+					l++
+				}
+			}
+		}
+		m[dst.entries[i].digest] = short
+		if i >= resetIdx {
+			l = length
+		}
+	}
+	return m
+}
+
+type digestEntry struct {
+	alg    digest.Algorithm
+	val    string
+	digest digest.Digest
+}
+
+type digestEntries []*digestEntry
+
+func (d digestEntries) Len() int {
+	return len(d)
+}
+
+func (d digestEntries) Less(i, j int) bool {
+	if d[i].val != d[j].val {
+		return d[i].val < d[j].val
+	}
+	return d[i].alg < d[j].alg
+}
+
+func (d digestEntries) Swap(i, j int) {
+	d[i], d[j] = d[j], d[i]
+}
--- a/vendor/github.com/docker/distribution/reference/helpers.go
+++ b/vendor/github.com/docker/distribution/reference/helpers.go
@@ -0,0 +1,42 @@
+package reference
+
+import "path"
+
+// IsNameOnly returns true if reference only contains a repo name.
+func IsNameOnly(ref Named) bool {
+	if _, ok := ref.(NamedTagged); ok {
+		return false
+	}
+	if _, ok := ref.(Canonical); ok {
+		return false
+	}
+	return true
+}
+
+// FamiliarName returns the familiar name string
+// for the given named, familiarizing if needed.
+func FamiliarName(ref Named) string {
+	if nn, ok := ref.(normalizedNamed); ok {
+		return nn.Familiar().Name()
+	}
+	return ref.Name()
+}
+
+// FamiliarString returns the familiar string representation
+// for the given reference, familiarizing if needed.
+func FamiliarString(ref Reference) string {
+	if nn, ok := ref.(normalizedNamed); ok {
+		return nn.Familiar().String()
+	}
+	return ref.String()
+}
+
+// FamiliarMatch reports whether ref matches the specified pattern.
+// See https://godoc.org/path#Match for supported patterns.
+func FamiliarMatch(pattern string, ref Reference) (bool, error) {
+	matched, err := path.Match(pattern, FamiliarString(ref))
+	if namedRef, isNamed := ref.(Named); isNamed && !matched {
+		matched, _ = path.Match(pattern, FamiliarName(namedRef))
+	}
+	return matched, err
+}
--- a/vendor/github.com/docker/distribution/reference/normalize.go
+++ b/vendor/github.com/docker/distribution/reference/normalize.go
@@ -0,0 +1,170 @@
+package reference
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/docker/distribution/digestset"
+	"github.com/opencontainers/go-digest"
+)
+
+var (
+	legacyDefaultDomain = "index.docker.io"
+	defaultDomain       = "docker.io"
+	officialRepoName    = "library"
+	defaultTag          = "latest"
+)
+
+// normalizedNamed represents a name which has been
+// normalized and has a familiar form. A familiar name
+// is what is used in Docker UI. An example normalized
+// name is "docker.io/library/ubuntu" and corresponding
+// familiar name of "ubuntu".
+type normalizedNamed interface {
+	Named
+	Familiar() Named
+}
+
+// ParseNormalizedNamed parses a string into a named reference
+// transforming a familiar name from Docker UI to a fully
+// qualified reference. If the value may be an identifier
+// use ParseAnyReference.
+func ParseNormalizedNamed(s string) (Named, error) {
+	if ok := anchoredIdentifierRegexp.MatchString(s); ok {
+		return nil, fmt.Errorf("invalid repository name (%s), cannot specify 64-byte hexadecimal strings", s)
+	}
+	domain, remainder := splitDockerDomain(s)
+	var remoteName string
+	if tagSep := strings.IndexRune(remainder, ':'); tagSep > -1 {
+		remoteName = remainder[:tagSep]
+	} else {
+		remoteName = remainder
+	}
+	if strings.ToLower(remoteName) != remoteName {
+		return nil, errors.New("invalid reference format: repository name must be lowercase")
+	}
+
+	ref, err := Parse(domain + "/" + remainder)
+	if err != nil {
+		return nil, err
+	}
+	named, isNamed := ref.(Named)
+	if !isNamed {
+		return nil, fmt.Errorf("reference %s has no name", ref.String())
+	}
+	return named, nil
+}
+
+// splitDockerDomain splits a repository name to domain and remotename string.
+// If no valid domain is found, the default domain is used. Repository name
+// needs to be already validated before.
+func splitDockerDomain(name string) (domain, remainder string) {
+	i := strings.IndexRune(name, '/')
+	if i == -1 || (!strings.ContainsAny(name[:i], ".:") && name[:i] != "localhost") {
+		domain, remainder = defaultDomain, name
+	} else {
+		domain, remainder = name[:i], name[i+1:]
+	}
+	if domain == legacyDefaultDomain {
+		domain = defaultDomain
+	}
+	if domain == defaultDomain && !strings.ContainsRune(remainder, '/') {
+		remainder = officialRepoName + "/" + remainder
+	}
+	return
+}
+
+// familiarizeName returns a shortened version of the name familiar
+// to to the Docker UI. Familiar names have the default domain
+// "docker.io" and "library/" repository prefix removed.
+// For example, "docker.io/library/redis" will have the familiar
+// name "redis" and "docker.io/dmcgowan/myapp" will be "dmcgowan/myapp".
+// Returns a familiarized named only reference.
+func familiarizeName(named namedRepository) repository {
+	repo := repository{
+		domain: named.Domain(),
+		path:   named.Path(),
+	}
+
+	if repo.domain == defaultDomain {
+		repo.domain = ""
+		// Handle official repositories which have the pattern "library/<official repo name>"
+		if split := strings.Split(repo.path, "/"); len(split) == 2 && split[0] == officialRepoName {
+			repo.path = split[1]
+		}
+	}
+	return repo
+}
+
+func (r reference) Familiar() Named {
+	return reference{
+		namedRepository: familiarizeName(r.namedRepository),
+		tag:             r.tag,
+		digest:          r.digest,
+	}
+}
+
+func (r repository) Familiar() Named {
+	return familiarizeName(r)
+}
+
+func (t taggedReference) Familiar() Named {
+	return taggedReference{
+		namedRepository: familiarizeName(t.namedRepository),
+		tag:             t.tag,
+	}
+}
+
+func (c canonicalReference) Familiar() Named {
+	return canonicalReference{
+		namedRepository: familiarizeName(c.namedRepository),
+		digest:          c.digest,
+	}
+}
+
+// TagNameOnly adds the default tag "latest" to a reference if it only has
+// a repo name.
+func TagNameOnly(ref Named) Named {
+	if IsNameOnly(ref) {
+		namedTagged, err := WithTag(ref, defaultTag)
+		if err != nil {
+			// Default tag must be valid, to create a NamedTagged
+			// type with non-validated input the WithTag function
+			// should be used instead
+			panic(err)
+		}
+		return namedTagged
+	}
+	return ref
+}
+
+// ParseAnyReference parses a reference string as a possible identifier,
+// full digest, or familiar name.
+func ParseAnyReference(ref string) (Reference, error) {
+	if ok := anchoredIdentifierRegexp.MatchString(ref); ok {
+		return digestReference("sha256:" + ref), nil
+	}
+	if dgst, err := digest.Parse(ref); err == nil {
+		return digestReference(dgst), nil
+	}
+
+	return ParseNormalizedNamed(ref)
+}
+
+// ParseAnyReferenceWithSet parses a reference string as a possible short
+// identifier to be matched in a digest set, a full digest, or familiar name.
+func ParseAnyReferenceWithSet(ref string, ds *digestset.Set) (Reference, error) {
+	if ok := anchoredShortIdentifierRegexp.MatchString(ref); ok {
+		dgst, err := ds.Lookup(ref)
+		if err == nil {
+			return digestReference(dgst), nil
+		}
+	} else {
+		if dgst, err := digest.Parse(ref); err == nil {
+			return digestReference(dgst), nil
+		}
+	}
+
+	return ParseNormalizedNamed(ref)
+}
--- a/vendor/github.com/docker/distribution/reference/reference.go
+++ b/vendor/github.com/docker/distribution/reference/reference.go
@@ -0,0 +1,433 @@
+// Package reference provides a general type to represent any way of referencing images within the registry.
+// Its main purpose is to abstract tags and digests (content-addressable hash).
+//
+// Grammar
+//
+// 	reference                       := name [ ":" tag ] [ "@" digest ]
+//	name                            := [domain '/'] path-component ['/' path-component]*
+//	domain                          := domain-component ['.' domain-component]* [':' port-number]
+//	domain-component                := /([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9-]*[a-zA-Z0-9])/
+//	port-number                     := /[0-9]+/
+//	path-component                  := alpha-numeric [separator alpha-numeric]*
+// 	alpha-numeric                   := /[a-z0-9]+/
+//	separator                       := /[_.]|__|[-]*/
+//
+//	tag                             := /[\w][\w.-]{0,127}/
+//
+//	digest                          := digest-algorithm ":" digest-hex
+//	digest-algorithm                := digest-algorithm-component [ digest-algorithm-separator digest-algorithm-component ]*
+//	digest-algorithm-separator      := /[+.-_]/
+//	digest-algorithm-component      := /[A-Za-z][A-Za-z0-9]*/
+//	digest-hex                      := /[0-9a-fA-F]{32,}/ ; At least 128 bit digest value
+//
+//	identifier                      := /[a-f0-9]{64}/
+//	short-identifier                := /[a-f0-9]{6,64}/
+package reference
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/opencontainers/go-digest"
+)
+
+const (
+	// NameTotalLengthMax is the maximum total number of characters in a repository name.
+	NameTotalLengthMax = 255
+)
+
+var (
+	// ErrReferenceInvalidFormat represents an error while trying to parse a string as a reference.
+	ErrReferenceInvalidFormat = errors.New("invalid reference format")
+
+	// ErrTagInvalidFormat represents an error while trying to parse a string as a tag.
+	ErrTagInvalidFormat = errors.New("invalid tag format")
+
+	// ErrDigestInvalidFormat represents an error while trying to parse a string as a tag.
+	ErrDigestInvalidFormat = errors.New("invalid digest format")
+
+	// ErrNameContainsUppercase is returned for invalid repository names that contain uppercase characters.
+	ErrNameContainsUppercase = errors.New("repository name must be lowercase")
+
+	// ErrNameEmpty is returned for empty, invalid repository names.
+	ErrNameEmpty = errors.New("repository name must have at least one component")
+
+	// ErrNameTooLong is returned when a repository name is longer than NameTotalLengthMax.
+	ErrNameTooLong = fmt.Errorf("repository name must not be more than %v characters", NameTotalLengthMax)
+
+	// ErrNameNotCanonical is returned when a name is not canonical.
+	ErrNameNotCanonical = errors.New("repository name must be canonical")
+)
+
+// Reference is an opaque object reference identifier that may include
+// modifiers such as a hostname, name, tag, and digest.
+type Reference interface {
+	// String returns the full reference
+	String() string
+}
+
+// Field provides a wrapper type for resolving correct reference types when
+// working with encoding.
+type Field struct {
+	reference Reference
+}
+
+// AsField wraps a reference in a Field for encoding.
+func AsField(reference Reference) Field {
+	return Field{reference}
+}
+
+// Reference unwraps the reference type from the field to
+// return the Reference object. This object should be
+// of the appropriate type to further check for different
+// reference types.
+func (f Field) Reference() Reference {
+	return f.reference
+}
+
+// MarshalText serializes the field to byte text which
+// is the string of the reference.
+func (f Field) MarshalText() (p []byte, err error) {
+	return []byte(f.reference.String()), nil
+}
+
+// UnmarshalText parses text bytes by invoking the
+// reference parser to ensure the appropriately
+// typed reference object is wrapped by field.
+func (f *Field) UnmarshalText(p []byte) error {
+	r, err := Parse(string(p))
+	if err != nil {
+		return err
+	}
+
+	f.reference = r
+	return nil
+}
+
+// Named is an object with a full name
+type Named interface {
+	Reference
+	Name() string
+}
+
+// Tagged is an object which has a tag
+type Tagged interface {
+	Reference
+	Tag() string
+}
+
+// NamedTagged is an object including a name and tag.
+type NamedTagged interface {
+	Named
+	Tag() string
+}
+
+// Digested is an object which has a digest
+// in which it can be referenced by
+type Digested interface {
+	Reference
+	Digest() digest.Digest
+}
+
+// Canonical reference is an object with a fully unique
+// name including a name with domain and digest
+type Canonical interface {
+	Named
+	Digest() digest.Digest
+}
+
+// namedRepository is a reference to a repository with a name.
+// A namedRepository has both domain and path components.
+type namedRepository interface {
+	Named
+	Domain() string
+	Path() string
+}
+
+// Domain returns the domain part of the Named reference
+func Domain(named Named) string {
+	if r, ok := named.(namedRepository); ok {
+		return r.Domain()
+	}
+	domain, _ := splitDomain(named.Name())
+	return domain
+}
+
+// Path returns the name without the domain part of the Named reference
+func Path(named Named) (name string) {
+	if r, ok := named.(namedRepository); ok {
+		return r.Path()
+	}
+	_, path := splitDomain(named.Name())
+	return path
+}
+
+func splitDomain(name string) (string, string) {
+	match := anchoredNameRegexp.FindStringSubmatch(name)
+	if len(match) != 3 {
+		return "", name
+	}
+	return match[1], match[2]
+}
+
+// SplitHostname splits a named reference into a
+// hostname and name string. If no valid hostname is
+// found, the hostname is empty and the full value
+// is returned as name
+// DEPRECATED: Use Domain or Path
+func SplitHostname(named Named) (string, string) {
+	if r, ok := named.(namedRepository); ok {
+		return r.Domain(), r.Path()
+	}
+	return splitDomain(named.Name())
+}
+
+// Parse parses s and returns a syntactically valid Reference.
+// If an error was encountered it is returned, along with a nil Reference.
+// NOTE: Parse will not handle short digests.
+func Parse(s string) (Reference, error) {
+	matches := ReferenceRegexp.FindStringSubmatch(s)
+	if matches == nil {
+		if s == "" {
+			return nil, ErrNameEmpty
+		}
+		if ReferenceRegexp.FindStringSubmatch(strings.ToLower(s)) != nil {
+			return nil, ErrNameContainsUppercase
+		}
+		return nil, ErrReferenceInvalidFormat
+	}
+
+	if len(matches[1]) > NameTotalLengthMax {
+		return nil, ErrNameTooLong
+	}
+
+	var repo repository
+
+	nameMatch := anchoredNameRegexp.FindStringSubmatch(matches[1])
+	if nameMatch != nil && len(nameMatch) == 3 {
+		repo.domain = nameMatch[1]
+		repo.path = nameMatch[2]
+	} else {
+		repo.domain = ""
+		repo.path = matches[1]
+	}
+
+	ref := reference{
+		namedRepository: repo,
+		tag:             matches[2],
+	}
+	if matches[3] != "" {
+		var err error
+		ref.digest, err = digest.Parse(matches[3])
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	r := getBestReferenceType(ref)
+	if r == nil {
+		return nil, ErrNameEmpty
+	}
+
+	return r, nil
+}
+
+// ParseNamed parses s and returns a syntactically valid reference implementing
+// the Named interface. The reference must have a name and be in the canonical
+// form, otherwise an error is returned.
+// If an error was encountered it is returned, along with a nil Reference.
+// NOTE: ParseNamed will not handle short digests.
+func ParseNamed(s string) (Named, error) {
+	named, err := ParseNormalizedNamed(s)
+	if err != nil {
+		return nil, err
+	}
+	if named.String() != s {
+		return nil, ErrNameNotCanonical
+	}
+	return named, nil
+}
+
+// WithName returns a named object representing the given string. If the input
+// is invalid ErrReferenceInvalidFormat will be returned.
+func WithName(name string) (Named, error) {
+	if len(name) > NameTotalLengthMax {
+		return nil, ErrNameTooLong
+	}
+
+	match := anchoredNameRegexp.FindStringSubmatch(name)
+	if match == nil || len(match) != 3 {
+		return nil, ErrReferenceInvalidFormat
+	}
+	return repository{
+		domain: match[1],
+		path:   match[2],
+	}, nil
+}
+
+// WithTag combines the name from "name" and the tag from "tag" to form a
+// reference incorporating both the name and the tag.
+func WithTag(name Named, tag string) (NamedTagged, error) {
+	if !anchoredTagRegexp.MatchString(tag) {
+		return nil, ErrTagInvalidFormat
+	}
+	var repo repository
+	if r, ok := name.(namedRepository); ok {
+		repo.domain = r.Domain()
+		repo.path = r.Path()
+	} else {
+		repo.path = name.Name()
+	}
+	if canonical, ok := name.(Canonical); ok {
+		return reference{
+			namedRepository: repo,
+			tag:             tag,
+			digest:          canonical.Digest(),
+		}, nil
+	}
+	return taggedReference{
+		namedRepository: repo,
+		tag:             tag,
+	}, nil
+}
+
+// WithDigest combines the name from "name" and the digest from "digest" to form
+// a reference incorporating both the name and the digest.
+func WithDigest(name Named, digest digest.Digest) (Canonical, error) {
+	if !anchoredDigestRegexp.MatchString(digest.String()) {
+		return nil, ErrDigestInvalidFormat
+	}
+	var repo repository
+	if r, ok := name.(namedRepository); ok {
+		repo.domain = r.Domain()
+		repo.path = r.Path()
+	} else {
+		repo.path = name.Name()
+	}
+	if tagged, ok := name.(Tagged); ok {
+		return reference{
+			namedRepository: repo,
+			tag:             tagged.Tag(),
+			digest:          digest,
+		}, nil
+	}
+	return canonicalReference{
+		namedRepository: repo,
+		digest:          digest,
+	}, nil
+}
+
+// TrimNamed removes any tag or digest from the named reference.
+func TrimNamed(ref Named) Named {
+	domain, path := SplitHostname(ref)
+	return repository{
+		domain: domain,
+		path:   path,
+	}
+}
+
+func getBestReferenceType(ref reference) Reference {
+	if ref.Name() == "" {
+		// Allow digest only references
+		if ref.digest != "" {
+			return digestReference(ref.digest)
+		}
+		return nil
+	}
+	if ref.tag == "" {
+		if ref.digest != "" {
+			return canonicalReference{
+				namedRepository: ref.namedRepository,
+				digest:          ref.digest,
+			}
+		}
+		return ref.namedRepository
+	}
+	if ref.digest == "" {
+		return taggedReference{
+			namedRepository: ref.namedRepository,
+			tag:             ref.tag,
+		}
+	}
+
+	return ref
+}
+
+type reference struct {
+	namedRepository
+	tag    string
+	digest digest.Digest
+}
+
+func (r reference) String() string {
+	return r.Name() + ":" + r.tag + "@" + r.digest.String()
+}
+
+func (r reference) Tag() string {
+	return r.tag
+}
+
+func (r reference) Digest() digest.Digest {
+	return r.digest
+}
+
+type repository struct {
+	domain string
+	path   string
+}
+
+func (r repository) String() string {
+	return r.Name()
+}
+
+func (r repository) Name() string {
+	if r.domain == "" {
+		return r.path
+	}
+	return r.domain + "/" + r.path
+}
+
+func (r repository) Domain() string {
+	return r.domain
+}
+
+func (r repository) Path() string {
+	return r.path
+}
+
+type digestReference digest.Digest
+
+func (d digestReference) String() string {
+	return digest.Digest(d).String()
+}
+
+func (d digestReference) Digest() digest.Digest {
+	return digest.Digest(d)
+}
+
+type taggedReference struct {
+	namedRepository
+	tag string
+}
+
+func (t taggedReference) String() string {
+	return t.Name() + ":" + t.tag
+}
+
+func (t taggedReference) Tag() string {
+	return t.tag
+}
+
+type canonicalReference struct {
+	namedRepository
+	digest digest.Digest
+}
+
+func (c canonicalReference) String() string {
+	return c.Name() + "@" + c.digest.String()
+}
+
+func (c canonicalReference) Digest() digest.Digest {
+	return c.digest
+}
--- a/vendor/github.com/docker/distribution/reference/regexp.go
+++ b/vendor/github.com/docker/distribution/reference/regexp.go
@@ -0,0 +1,143 @@
+package reference
+
+import "regexp"
+
+var (
+	// alphaNumericRegexp defines the alpha numeric atom, typically a
+	// component of names. This only allows lower case characters and digits.
+	alphaNumericRegexp = match(`[a-z0-9]+`)
+
+	// separatorRegexp defines the separators allowed to be embedded in name
+	// components. This allow one period, one or two underscore and multiple
+	// dashes.
+	separatorRegexp = match(`(?:[._]|__|[-]*)`)
+
+	// nameComponentRegexp restricts registry path component names to start
+	// with at least one letter or number, with following parts able to be
+	// separated by one period, one or two underscore and multiple dashes.
+	nameComponentRegexp = expression(
+		alphaNumericRegexp,
+		optional(repeated(separatorRegexp, alphaNumericRegexp)))
+
+	// domainComponentRegexp restricts the registry domain component of a
+	// repository name to start with a component as defined by DomainRegexp
+	// and followed by an optional port.
+	domainComponentRegexp = match(`(?:[a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9-]*[a-zA-Z0-9])`)
+
+	// DomainRegexp defines the structure of potential domain components
+	// that may be part of image names. This is purposely a subset of what is
+	// allowed by DNS to ensure backwards compatibility with Docker image
+	// names.
+	DomainRegexp = expression(
+		domainComponentRegexp,
+		optional(repeated(literal(`.`), domainComponentRegexp)),
+		optional(literal(`:`), match(`[0-9]+`)))
+
+	// TagRegexp matches valid tag names. From docker/docker:graph/tags.go.
+	TagRegexp = match(`[\w][\w.-]{0,127}`)
+
+	// anchoredTagRegexp matches valid tag names, anchored at the start and
+	// end of the matched string.
+	anchoredTagRegexp = anchored(TagRegexp)
+
+	// DigestRegexp matches valid digests.
+	DigestRegexp = match(`[A-Za-z][A-Za-z0-9]*(?:[-_+.][A-Za-z][A-Za-z0-9]*)*[:][[:xdigit:]]{32,}`)
+
+	// anchoredDigestRegexp matches valid digests, anchored at the start and
+	// end of the matched string.
+	anchoredDigestRegexp = anchored(DigestRegexp)
+
+	// NameRegexp is the format for the name component of references. The
+	// regexp has capturing groups for the domain and name part omitting
+	// the separating forward slash from either.
+	NameRegexp = expression(
+		optional(DomainRegexp, literal(`/`)),
+		nameComponentRegexp,
+		optional(repeated(literal(`/`), nameComponentRegexp)))
+
+	// anchoredNameRegexp is used to parse a name value, capturing the
+	// domain and trailing components.
+	anchoredNameRegexp = anchored(
+		optional(capture(DomainRegexp), literal(`/`)),
+		capture(nameComponentRegexp,
+			optional(repeated(literal(`/`), nameComponentRegexp))))
+
+	// ReferenceRegexp is the full supported format of a reference. The regexp
+	// is anchored and has capturing groups for name, tag, and digest
+	// components.
+	ReferenceRegexp = anchored(capture(NameRegexp),
+		optional(literal(":"), capture(TagRegexp)),
+		optional(literal("@"), capture(DigestRegexp)))
+
+	// IdentifierRegexp is the format for string identifier used as a
+	// content addressable identifier using sha256. These identifiers
+	// are like digests without the algorithm, since sha256 is used.
+	IdentifierRegexp = match(`([a-f0-9]{64})`)
+
+	// ShortIdentifierRegexp is the format used to represent a prefix
+	// of an identifier. A prefix may be used to match a sha256 identifier
+	// within a list of trusted identifiers.
+	ShortIdentifierRegexp = match(`([a-f0-9]{6,64})`)
+
+	// anchoredIdentifierRegexp is used to check or match an
+	// identifier value, anchored at start and end of string.
+	anchoredIdentifierRegexp = anchored(IdentifierRegexp)
+
+	// anchoredShortIdentifierRegexp is used to check if a value
+	// is a possible identifier prefix, anchored at start and end
+	// of string.
+	anchoredShortIdentifierRegexp = anchored(ShortIdentifierRegexp)
+)
+
+// match compiles the string to a regular expression.
+var match = regexp.MustCompile
+
+// literal compiles s into a literal regular expression, escaping any regexp
+// reserved characters.
+func literal(s string) *regexp.Regexp {
+	re := match(regexp.QuoteMeta(s))
+
+	if _, complete := re.LiteralPrefix(); !complete {
+		panic("must be a literal")
+	}
+
+	return re
+}
+
+// expression defines a full expression, where each regular expression must
+// follow the previous.
+func expression(res ...*regexp.Regexp) *regexp.Regexp {
+	var s string
+	for _, re := range res {
+		s += re.String()
+	}
+
+	return match(s)
+}
+
+// optional wraps the expression in a non-capturing group and makes the
+// production optional.
+func optional(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(group(expression(res...)).String() + `?`)
+}
+
+// repeated wraps the regexp in a non-capturing group to get one or more
+// matches.
+func repeated(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(group(expression(res...)).String() + `+`)
+}
+
+// group wraps the regexp in a non-capturing group.
+func group(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(`(?:` + expression(res...).String() + `)`)
+}
+
+// capture wraps the expression in a capturing group.
+func capture(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(`(` + expression(res...).String() + `)`)
+}
+
+// anchored anchors the regular expression by adding start and end delimiters.
+func anchored(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(`^` + expression(res...).String() + `$`)
+}
--- a/vendor/github.com/docker/distribution/vendor.conf
+++ b/vendor/github.com/docker/distribution/vendor.conf
@@ -0,0 +1,43 @@
+github.com/Azure/azure-sdk-for-go 088007b3b08cc02b27f2eadfdcd870958460ce7e
+github.com/Azure/go-autorest ec5f4903f77ed9927ac95b19ab8e44ada64c1356
+github.com/sirupsen/logrus 3d4380f53a34dcdc95f0c1db702615992b38d9a4
+github.com/aws/aws-sdk-go c6fc52983ea2375810aa38ddb5370e9cdf611716
+github.com/bshuster-repo/logrus-logstash-hook d2c0ecc1836d91814e15e23bb5dc309c3ef51f4a
+github.com/bugsnag/bugsnag-go b1d153021fcd90ca3f080db36bec96dc690fb274
+github.com/bugsnag/osext 0dd3f918b21bec95ace9dc86c7e70266cfc5c702
+github.com/bugsnag/panicwrap e2c28503fcd0675329da73bf48b33404db873782
+github.com/denverdino/aliyungo afedced274aa9a7fcdd47ac97018f0f8db4e5de2
+github.com/dgrijalva/jwt-go a601269ab70c205d26370c16f7c81e9017c14e04
+github.com/docker/goamz f0a21f5b2e12f83a505ecf79b633bb2035cf6f85
+github.com/docker/libtrust fa567046d9b14f6aa788882a950d69651d230b21
+github.com/garyburd/redigo 535138d7bcd717d6531c701ef5933d98b1866257
+github.com/go-ini/ini 2ba15ac2dc9cdf88c110ec2dc0ced7fa45f5678c
+github.com/golang/protobuf 8d92cf5fc15a4382f8964b08e1f42a75c0591aa3
+github.com/gorilla/context 14f550f51af52180c2eefed15e5fd18d63c0a64a
+github.com/gorilla/handlers 60c7bfde3e33c201519a200a4507a158cc03a17b
+github.com/gorilla/mux 599cba5e7b6137d46ddf58fb1765f5d928e69604
+github.com/inconshreveable/mousetrap 76626ae9c91c4f2a10f34cad8ce83ea42c93bb75
+github.com/jmespath/go-jmespath bd40a432e4c76585ef6b72d3fd96fb9b6dc7b68d
+github.com/miekg/dns 271c58e0c14f552178ea321a545ff9af38930f39
+github.com/mitchellh/mapstructure 482a9fd5fa83e8c4e7817413b80f3eb8feec03ef
+github.com/ncw/swift b964f2ca856aac39885e258ad25aec08d5f64ee6
+github.com/spf13/cobra 312092086bed4968099259622145a0c9ae280064
+github.com/spf13/pflag 5644820622454e71517561946e3d94b9f9db6842
+github.com/stevvooe/resumable 2aaf90b2ceea5072cb503ef2a620b08ff3119870
+github.com/xenolf/lego a9d8cec0e6563575e5868a005359ac97911b5985
+github.com/yvasiyarov/go-metrics 57bccd1ccd43f94bb17fdd8bf3007059b802f85e
+github.com/yvasiyarov/gorelic a9bba5b9ab508a086f9a12b8c51fab68478e2128
+github.com/yvasiyarov/newrelic_platform_go b21fdbd4370f3717f3bbd2bf41c223bc273068e6
+golang.org/x/crypto c10c31b5e94b6f7a0283272dc2bb27163dcea24b
+golang.org/x/net 4876518f9e71663000c348837735820161a42df7
+golang.org/x/oauth2 045497edb6234273d67dbc25da3f2ddbc4c4cacf
+golang.org/x/time a4bde12657593d5e90d0533a3e4fd95e635124cb
+google.golang.org/api 9bf6e6e569ff057f75d9604a46c52928f17d2b54
+google.golang.org/appengine 12d5545dc1cfa6047a286d5e853841b6471f4c19
+google.golang.org/cloud 975617b05ea8a58727e6c1a06b6161ff4185a9f2
+google.golang.org/grpc d3ddb4469d5a1b949fc7a7da7c1d6a0d1b6de994
+gopkg.in/check.v1 64131543e7896d5bcc6bd5a76287eb75ea96c673
+gopkg.in/square/go-jose.v1 40d457b439244b546f023d056628e5184136899b
+gopkg.in/yaml.v2 bef53efd0c76e49e6de55ead051f886bea7e9420
+rsc.io/letsencrypt e770c10b0f1a64775ae91d240407ce00d1a5bdeb https://github.com/dmcgowan/letsencrypt.git
+github.com/opencontainers/go-digest a6d0ee40d4207ea02364bd3b9e8e77b9159ba1eb