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diff --git a/kube2msb/src/vendor/github.com/Sirupsen/logrus/README.md b/kube2msb/src/vendor/github.com/Sirupsen/logrus/README.md deleted file mode 100644 index b6aa84c..0000000 --- a/kube2msb/src/vendor/github.com/Sirupsen/logrus/README.md +++ /dev/null @@ -1,352 +0,0 @@ -# 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 |