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vendor/github.com/rcrowley/go-metrics/README.md

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+go-metrics
+==========
+
+![travis build status](https://travis-ci.org/rcrowley/go-metrics.svg?branch=master)
+
+Go port of Coda Hale's Metrics library: <https://github.com/dropwizard/metrics>.
+
+Documentation: <http://godoc.org/github.com/rcrowley/go-metrics>.
+
+Usage
+-----
+
+Create and update metrics:
+
+```go
+c := metrics.NewCounter()
+metrics.Register("foo", c)
+c.Inc(47)
+
+g := metrics.NewGauge()
+metrics.Register("bar", g)
+g.Update(47)
+
+s := metrics.NewExpDecaySample(1028, 0.015) // or metrics.NewUniformSample(1028)
+h := metrics.NewHistogram(s)
+metrics.Register("baz", h)
+h.Update(47)
+
+m := metrics.NewMeter()
+metrics.Register("quux", m)
+m.Mark(47)
+
+t := metrics.NewTimer()
+metrics.Register("bang", t)
+t.Time(func() {})
+t.Update(47)
+```
+
+Periodically log every metric in human-readable form to standard error:
+
+```go
+go metrics.Log(metrics.DefaultRegistry, 5 * time.Second, log.New(os.Stderr, "metrics: ", log.Lmicroseconds))
+```
+
+Periodically log every metric in slightly-more-parseable form to syslog:
+
+```go
+w, _ := syslog.Dial("unixgram", "/dev/log", syslog.LOG_INFO, "metrics")
+go metrics.Syslog(metrics.DefaultRegistry, 60e9, w)
+```
+
+Periodically emit every metric to Graphite using the [Graphite client](https://github.com/cyberdelia/go-metrics-graphite):
+
+```go
+
+import "github.com/cyberdelia/go-metrics-graphite"
+
+addr, _ := net.ResolveTCPAddr("tcp", "127.0.0.1:2003")
+go graphite.Graphite(metrics.DefaultRegistry, 10e9, "metrics", addr)
+```
+
+Periodically emit every metric into InfluxDB:
+
+**NOTE:** this has been pulled out of the library due to constant fluctuations
+in the InfluxDB API. In fact, all client libraries are on their way out. see
+issues [#121](https://github.com/rcrowley/go-metrics/issues/121) and
+[#124](https://github.com/rcrowley/go-metrics/issues/124) for progress and details.
+
+```go
+import "github.com/rcrowley/go-metrics/influxdb"
+
+go influxdb.Influxdb(metrics.DefaultRegistry, 10e9, &influxdb.Config{
+    Host:     "127.0.0.1:8086",
+    Database: "metrics",
+    Username: "test",
+    Password: "test",
+})
+```
+
+Periodically upload every metric to Librato using the [Librato client](https://github.com/mihasya/go-metrics-librato):
+
+**Note**: the client included with this repository under the `librato` package
+has been deprecated and moved to the repository linked above.
+
+```go
+import "github.com/mihasya/go-metrics-librato"
+
+go librato.Librato(metrics.DefaultRegistry,
+    10e9,                  // interval
+    "example@example.com", // account owner email address
+    "token",               // Librato API token
+    "hostname",            // source
+    []float64{0.95},       // percentiles to send
+    time.Millisecond,      // time unit
+)
+```
+
+Periodically emit every metric to StatHat:
+
+```go
+import "github.com/rcrowley/go-metrics/stathat"
+
+go stathat.Stathat(metrics.DefaultRegistry, 10e9, "example@example.com")
+```
+
+Maintain all metrics along with expvars at `/debug/metrics`:
+
+This uses the same mechanism as [the official expvar](http://golang.org/pkg/expvar/)
+but exposed under `/debug/metrics`, which shows a json representation of all your usual expvars
+as well as all your go-metrics.
+
+
+```go
+import "github.com/rcrowley/go-metrics/exp"
+
+exp.Exp(metrics.DefaultRegistry)
+```
+
+Installation
+------------
+
+```sh
+go get github.com/rcrowley/go-metrics
+```
+
+StatHat support additionally requires their Go client:
+
+```sh
+go get github.com/stathat/go
+```
+
+Publishing Metrics
+------------------
+
+Clients are available for the following destinations:
+
+* Librato - [https://github.com/mihasya/go-metrics-librato](https://github.com/mihasya/go-metrics-librato)
+* Graphite - [https://github.com/cyberdelia/go-metrics-graphite](https://github.com/cyberdelia/go-metrics-graphite)
+* InfluxDB - [https://github.com/vrischmann/go-metrics-influxdb](https://github.com/vrischmann/go-metrics-influxdb)