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diff --git a/src/kube2msb/vendor/github.com/Sirupsen/logrus/README.md b/src/kube2msb/vendor/github.com/Sirupsen/logrus/README.md new file mode 100644 index 0000000..b6aa84c --- /dev/null +++ b/src/kube2msb/vendor/github.com/Sirupsen/logrus/README.md @@ -0,0 +1,352 @@ +# Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/> [](https://travis-ci.org/Sirupsen/logrus) + +Logrus is a structured logger for Go (golang), completely API compatible with +the standard library logger. [Godoc][godoc]. **Please note the Logrus API is not +yet stable (pre 1.0), the core API is unlikely change much but please version +control your Logrus to make sure you aren't fetching latest `master` on every +build.** + +Nicely color-coded in development (when a TTY is attached, otherwise just +plain text): + + + +With `log.Formatter = new(logrus.JSONFormatter)`, for easy parsing by logstash +or Splunk: + +```json +{"animal":"walrus","level":"info","msg":"A group of walrus emerges from the +ocean","size":10,"time":"2014-03-10 19:57:38.562264131 -0400 EDT"} + +{"level":"warning","msg":"The group's number increased tremendously!", +"number":122,"omg":true,"time":"2014-03-10 19:57:38.562471297 -0400 EDT"} + +{"animal":"walrus","level":"info","msg":"A giant walrus appears!", +"size":10,"time":"2014-03-10 19:57:38.562500591 -0400 EDT"} + +{"animal":"walrus","level":"info","msg":"Tremendously sized cow enters the ocean.", +"size":9,"time":"2014-03-10 19:57:38.562527896 -0400 EDT"} + +{"level":"fatal","msg":"The ice breaks!","number":100,"omg":true, +"time":"2014-03-10 19:57:38.562543128 -0400 EDT"} +``` + +With the default `log.Formatter = new(logrus.TextFormatter)` when a TTY is not +attached, the output is compatible with the +[l2met](http://r.32k.io/l2met-introduction) format: + +```text +time="2014-04-20 15:36:23.830442383 -0400 EDT" level="info" msg="A group of walrus emerges from the ocean" animal="walrus" size=10 +time="2014-04-20 15:36:23.830584199 -0400 EDT" level="warning" msg="The group's number increased tremendously!" omg=true number=122 +time="2014-04-20 15:36:23.830596521 -0400 EDT" level="info" msg="A giant walrus appears!" animal="walrus" size=10 +time="2014-04-20 15:36:23.830611837 -0400 EDT" level="info" msg="Tremendously sized cow enters the ocean." animal="walrus" size=9 +time="2014-04-20 15:36:23.830626464 -0400 EDT" level="fatal" msg="The ice breaks!" omg=true number=100 +``` + +#### Example + +The simplest way to use Logrus is simply the package-level exported logger: + +```go +package main + +import ( + log "github.com/Sirupsen/logrus" +) + +func main() { + log.WithFields(log.Fields{ + "animal": "walrus", + }).Info("A walrus appears") +} +``` + +Note that it's completely api-compatible with the stdlib logger, so you can +replace your `log` imports everywhere with `log "github.com/Sirupsen/logrus"` +and you'll now have the flexibility of Logrus. You can customize it all you +want: + +```go +package main + +import ( + "os" + log "github.com/Sirupsen/logrus" + "github.com/Sirupsen/logrus/hooks/airbrake" +) + +func init() { + // Log as JSON instead of the default ASCII formatter. + log.SetFormatter(&log.JSONFormatter{}) + + // Use the Airbrake hook to report errors that have Error severity or above to + // an exception tracker. You can create custom hooks, see the Hooks section. + log.AddHook(&logrus_airbrake.AirbrakeHook{}) + + // Output to stderr instead of stdout, could also be a file. + log.SetOutput(os.Stderr) + + // Only log the warning severity or above. + log.SetLevel(log.WarnLevel) +} + +func main() { + log.WithFields(log.Fields{ + "animal": "walrus", + "size": 10, + }).Info("A group of walrus emerges from the ocean") + + log.WithFields(log.Fields{ + "omg": true, + "number": 122, + }).Warn("The group's number increased tremendously!") + + log.WithFields(log.Fields{ + "omg": true, + "number": 100, + }).Fatal("The ice breaks!") +} +``` + +For more advanced usage such as logging to multiple locations from the same +application, you can also create an instance of the `logrus` Logger: + +```go +package main + +import ( + "github.com/Sirupsen/logrus" +) + +// Create a new instance of the logger. You can have any number of instances. +var log = logrus.New() + +func main() { + // The API for setting attributes is a little different than the package level + // exported logger. See Godoc. + log.Out = os.Stderr + + log.WithFields(logrus.Fields{ + "animal": "walrus", + "size": 10, + }).Info("A group of walrus emerges from the ocean") +} +``` + +#### Fields + +Logrus encourages careful, structured logging though logging fields instead of +long, unparseable error messages. For example, instead of: `log.Fatalf("Failed +to send event %s to topic %s with key %d")`, you should log the much more +discoverable: + +```go +log.WithFields(log.Fields{ + "event": event, + "topic": topic, + "key": key, +}).Fatal("Failed to send event") +``` + +We've found this API forces you to think about logging in a way that produces +much more useful logging messages. We've been in countless situations where just +a single added field to a log statement that was already there would've saved us +hours. The `WithFields` call is optional. + +In general, with Logrus using any of the `printf`-family functions should be +seen as a hint you should add a field, however, you can still use the +`printf`-family functions with Logrus. + +#### Hooks + +You can add hooks for logging levels. For example to send errors to an exception +tracking service on `Error`, `Fatal` and `Panic`, info to StatsD or log to +multiple places simultaneously, e.g. syslog. + +```go +// Not the real implementation of the Airbrake hook. Just a simple sample. +import ( + log "github.com/Sirupsen/logrus" +) + +func init() { + log.AddHook(new(AirbrakeHook)) +} + +type AirbrakeHook struct{} + +// `Fire()` takes the entry that the hook is fired for. `entry.Data[]` contains +// the fields for the entry. See the Fields section of the README. +func (hook *AirbrakeHook) Fire(entry *logrus.Entry) error { + err := airbrake.Notify(entry.Data["error"].(error)) + if err != nil { + log.WithFields(log.Fields{ + "source": "airbrake", + "endpoint": airbrake.Endpoint, + }).Info("Failed to send error to Airbrake") + } + + return nil +} + +// `Levels()` returns a slice of `Levels` the hook is fired for. +func (hook *AirbrakeHook) Levels() []log.Level { + return []log.Level{ + log.ErrorLevel, + log.FatalLevel, + log.PanicLevel, + } +} +``` + +Logrus comes with built-in hooks. Add those, or your custom hook, in `init`: + +```go +import ( + log "github.com/Sirupsen/logrus" + "github.com/Sirupsen/logrus/hooks/airbrake" + "github.com/Sirupsen/logrus/hooks/syslog" + "log/syslog" +) + +func init() { + log.AddHook(new(logrus_airbrake.AirbrakeHook)) + + hook, err := logrus_syslog.NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "") + if err != nil { + log.Error("Unable to connect to local syslog daemon") + } else { + log.AddHook(hook) + } +} +``` + +* [`github.com/Sirupsen/logrus/hooks/airbrake`](https://github.com/Sirupsen/logrus/blob/master/hooks/airbrake/airbrake.go) + Send errors to an exception tracking service compatible with the Airbrake API. + Uses [`airbrake-go`](https://github.com/tobi/airbrake-go) behind the scenes. + +* [`github.com/Sirupsen/logrus/hooks/papertrail`](https://github.com/Sirupsen/logrus/blob/master/hooks/papertrail/papertrail.go) + Send errors to the Papertrail hosted logging service via UDP. + +* [`github.com/Sirupsen/logrus/hooks/syslog`](https://github.com/Sirupsen/logrus/blob/master/hooks/syslog/syslog.go) + Send errors to remote syslog server. + Uses standard library `log/syslog` behind the scenes. + +* [`github.com/nubo/hiprus`](https://github.com/nubo/hiprus) + Send errors to a channel in hipchat. + +* [`github.com/sebest/logrusly`](https://github.com/sebest/logrusly) + Send logs to Loggly (https://www.loggly.com/) + +#### Level logging + +Logrus has six logging levels: Debug, Info, Warning, Error, Fatal and Panic. + +```go +log.Debug("Useful debugging information.") +log.Info("Something noteworthy happened!") +log.Warn("You should probably take a look at this.") +log.Error("Something failed but I'm not quitting.") +// Calls os.Exit(1) after logging +log.Fatal("Bye.") +// Calls panic() after logging +log.Panic("I'm bailing.") +``` + +You can set the logging level on a `Logger`, then it will only log entries with +that severity or anything above it: + +```go +// Will log anything that is info or above (warn, error, fatal, panic). Default. +log.SetLevel(log.InfoLevel) +``` + +It may be useful to set `log.Level = logrus.DebugLevel` in a debug or verbose +environment if your application has that. + +#### Entries + +Besides the fields added with `WithField` or `WithFields` some fields are +automatically added to all logging events: + +1. `time`. The timestamp when the entry was created. +2. `msg`. The logging message passed to `{Info,Warn,Error,Fatal,Panic}` after + the `AddFields` call. E.g. `Failed to send event.` +3. `level`. The logging level. E.g. `info`. + +#### Environments + +Logrus has no notion of environment. + +If you wish for hooks and formatters to only be used in specific environments, +you should handle that yourself. For example, if your application has a global +variable `Environment`, which is a string representation of the environment you +could do: + +```go +import ( + log "github.com/Sirupsen/logrus" +) + +init() { + // do something here to set environment depending on an environment variable + // or command-line flag + if Environment == "production" { + log.SetFormatter(logrus.JSONFormatter) + } else { + // The TextFormatter is default, you don't actually have to do this. + log.SetFormatter(logrus.TextFormatter) + } +} +``` + +This configuration is how `logrus` was intended to be used, but JSON in +production is mostly only useful if you do log aggregation with tools like +Splunk or Logstash. + +#### Formatters + +The built-in logging formatters are: + +* `logrus.TextFormatter`. Logs the event in colors if stdout is a tty, otherwise + without colors. + * *Note:* to force colored output when there is no TTY, set the `ForceColors` + field to `true`. To force no colored output even if there is a TTY set the + `DisableColors` field to `true` +* `logrus.JSONFormatter`. Logs fields as JSON. + +Third party logging formatters: + +* [`zalgo`](https://github.com/aybabtme/logzalgo): invoking the P͉̫o̳̼̊w̖͈̰͎e̬͔̭͂r͚̼̹̲ ̫͓͉̳͈ō̠͕͖̚f̝͍̠ ͕̲̞͖͑Z̖̫̤̫ͪa͉̬͈̗l͖͎g̳̥o̰̥̅!̣͔̲̻͊̄ ̙̘̦̹̦. + +You can define your formatter by implementing the `Formatter` interface, +requiring a `Format` method. `Format` takes an `*Entry`. `entry.Data` is a +`Fields` type (`map[string]interface{}`) with all your fields as well as the +default ones (see Entries section above): + +```go +type MyJSONFormatter struct { +} + +log.SetFormatter(new(MyJSONFormatter)) + +func (f *JSONFormatter) Format(entry *Entry) ([]byte, error) { + // Note this doesn't include Time, Level and Message which are available on + // the Entry. Consult `godoc` on information about those fields or read the + // source of the official loggers. + serialized, err := json.Marshal(entry.Data) + if err != nil { + return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err) + } + return append(serialized, '\n'), nil +} +``` + +#### Rotation + +Log rotation is not provided with Logrus. Log rotation should be done by an +external program (like `logrotated(8)`) that can compress and delete old log +entries. It should not be a feature of the application-level logger. + + +[godoc]: https://godoc.org/github.com/Sirupsen/logrus |