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diff --git a/vendor/github.com/Sirupsen/logrus/README.md b/vendor/github.com/Sirupsen/logrus/README.md deleted file mode 100644 index 640cf61..0000000 --- a/vendor/github.com/Sirupsen/logrus/README.md +++ /dev/null @@ -1,476 +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) [](https://godoc.org/github.com/Sirupsen/logrus) - -**Seeing weird case-sensitive problems?** See [this -issue](https://github.com/sirupsen/logrus/issues/451#issuecomment-264332021). -This change has been reverted. I apologize for causing this. I greatly -underestimated the impact this would have. Logrus strives for stability and -backwards compatibility and failed to provide that. - -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). Logrus itself is completely stable and has been used in -many large deployments. The core API is unlikely to 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.SetFormatter(&log.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.SetFormatter(&log.TextFormatter{})` when a TTY is not -attached, the output is compatible with the -[logfmt](http://godoc.org/github.com/kr/logfmt) format: - -```text -time="2015-03-26T01:27:38-04:00" level=debug msg="Started observing beach" animal=walrus number=8 -time="2015-03-26T01:27:38-04:00" level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10 -time="2015-03-26T01:27:38-04:00" level=warning msg="The group's number increased tremendously!" number=122 omg=true -time="2015-03-26T01:27:38-04:00" level=debug msg="Temperature changes" temperature=-4 -time="2015-03-26T01:27:38-04:00" level=panic msg="It's over 9000!" animal=orca size=9009 -time="2015-03-26T01:27:38-04:00" level=fatal msg="The ice breaks!" err=&{0x2082280c0 map[animal:orca size:9009] 2015-03-26 01:27:38.441574009 -0400 EDT panic It's over 9000!} number=100 omg=true -exit status 1 -``` - -#### 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" -) - -func init() { - // Log as JSON instead of the default ASCII formatter. - log.SetFormatter(&log.JSONFormatter{}) - - // Output to stdout instead of the default stderr - // Can be any io.Writer, see below for File example - log.SetOutput(os.Stdout) - - // 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!") - - // A common pattern is to re-use fields between logging statements by re-using - // the logrus.Entry returned from WithFields() - contextLogger := log.WithFields(log.Fields{ - "common": "this is a common field", - "other": "I also should be logged always", - }) - - contextLogger.Info("I'll be logged with common and other field") - contextLogger.Info("Me too") -} -``` - -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.Stdout - - // You could set this to any `io.Writer` such as a file - // file, err := os.OpenFile("logrus.log", os.O_CREATE|os.O_WRONLY, 0666) - // if err == nil { - // log.Out = file - // } else { - // log.Info("Failed to log to file, using default 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. - -#### Default Fields - -Often it's helpful to have fields _always_ attached to log statements in an -application or parts of one. For example, you may want to always log the -`request_id` and `user_ip` in the context of a request. Instead of writing -`log.WithFields(log.Fields{"request_id": request_id, "user_ip": user_ip})` on -every line, you can create a `logrus.Entry` to pass around instead: - -```go -requestLogger := log.WithFields(log.Fields{"request_id": request_id, user_ip: user_ip}) -requestLogger.Info("something happened on that request") # will log request_id and user_ip -requestLogger.Warn("something not great happened") -``` - -#### 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. - -Logrus comes with [built-in hooks](hooks/). Add those, or your custom hook, in -`init`: - -```go -import ( - log "github.com/Sirupsen/logrus" - "gopkg.in/gemnasium/logrus-airbrake-hook.v2" // the package is named "aibrake" - logrus_syslog "github.com/Sirupsen/logrus/hooks/syslog" - "log/syslog" -) - -func init() { - - // 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(airbrake.NewHook(123, "xyz", "production")) - - 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) - } -} -``` -Note: Syslog hook also support connecting to local syslog (Ex. "/dev/log" or "/var/run/syslog" or "/var/run/log"). For the detail, please check the [syslog hook README](hooks/syslog/README.md). - -| Hook | Description | -| ----- | ----------- | -| [Airbrake "legacy"](https://github.com/gemnasium/logrus-airbrake-legacy-hook) | Send errors to an exception tracking service compatible with the Airbrake API V2. Uses [`airbrake-go`](https://github.com/tobi/airbrake-go) behind the scenes. | -| [Airbrake](https://github.com/gemnasium/logrus-airbrake-hook) | Send errors to the Airbrake API V3. Uses the official [`gobrake`](https://github.com/airbrake/gobrake) behind the scenes. | -| [Amazon Kinesis](https://github.com/evalphobia/logrus_kinesis) | Hook for logging to [Amazon Kinesis](https://aws.amazon.com/kinesis/) | -| [Amqp-Hook](https://github.com/vladoatanasov/logrus_amqp) | Hook for logging to Amqp broker (Like RabbitMQ) | -| [Bugsnag](https://github.com/Shopify/logrus-bugsnag/blob/master/bugsnag.go) | Send errors to the Bugsnag exception tracking service. | -| [DeferPanic](https://github.com/deferpanic/dp-logrus) | Hook for logging to DeferPanic | -| [ElasticSearch](https://github.com/sohlich/elogrus) | Hook for logging to ElasticSearch| -| [Fluentd](https://github.com/evalphobia/logrus_fluent) | Hook for logging to fluentd | -| [Go-Slack](https://github.com/multiplay/go-slack) | Hook for logging to [Slack](https://slack.com) | -| [Graylog](https://github.com/gemnasium/logrus-graylog-hook) | Hook for logging to [Graylog](http://graylog2.org/) | -| [Hiprus](https://github.com/nubo/hiprus) | Send errors to a channel in hipchat. | -| [Honeybadger](https://github.com/agonzalezro/logrus_honeybadger) | Hook for sending exceptions to Honeybadger | -| [InfluxDB](https://github.com/Abramovic/logrus_influxdb) | Hook for logging to influxdb | -| [Influxus] (http://github.com/vlad-doru/influxus) | Hook for concurrently logging to [InfluxDB] (http://influxdata.com/) | -| [Journalhook](https://github.com/wercker/journalhook) | Hook for logging to `systemd-journald` | -| [KafkaLogrus](https://github.com/goibibo/KafkaLogrus) | Hook for logging to kafka | -| [LFShook](https://github.com/rifflock/lfshook) | Hook for logging to the local filesystem | -| [Logentries](https://github.com/jcftang/logentriesrus) | Hook for logging to [Logentries](https://logentries.com/) | -| [Logentrus](https://github.com/puddingfactory/logentrus) | Hook for logging to [Logentries](https://logentries.com/) | -| [Logmatic.io](https://github.com/logmatic/logmatic-go) | Hook for logging to [Logmatic.io](http://logmatic.io/) | -| [Logrusly](https://github.com/sebest/logrusly) | Send logs to [Loggly](https://www.loggly.com/) | -| [Logstash](https://github.com/bshuster-repo/logrus-logstash-hook) | Hook for logging to [Logstash](https://www.elastic.co/products/logstash) | -| [Mail](https://github.com/zbindenren/logrus_mail) | Hook for sending exceptions via mail | -| [Mongodb](https://github.com/weekface/mgorus) | Hook for logging to mongodb | -| [NATS-Hook](https://github.com/rybit/nats_logrus_hook) | Hook for logging to [NATS](https://nats.io) | -| [Octokit](https://github.com/dorajistyle/logrus-octokit-hook) | Hook for logging to github via octokit | -| [Papertrail](https://github.com/polds/logrus-papertrail-hook) | Send errors to the [Papertrail](https://papertrailapp.com) hosted logging service via UDP. | -| [PostgreSQL](https://github.com/gemnasium/logrus-postgresql-hook) | Send logs to [PostgreSQL](http://postgresql.org) | -| [Pushover](https://github.com/toorop/logrus_pushover) | Send error via [Pushover](https://pushover.net) | -| [Raygun](https://github.com/squirkle/logrus-raygun-hook) | Hook for logging to [Raygun.io](http://raygun.io/) | -| [Redis-Hook](https://github.com/rogierlommers/logrus-redis-hook) | Hook for logging to a ELK stack (through Redis) | -| [Rollrus](https://github.com/heroku/rollrus) | Hook for sending errors to rollbar | -| [Scribe](https://github.com/sagar8192/logrus-scribe-hook) | Hook for logging to [Scribe](https://github.com/facebookarchive/scribe)| -| [Sentry](https://github.com/evalphobia/logrus_sentry) | Send errors to the Sentry error logging and aggregation service. | -| [Slackrus](https://github.com/johntdyer/slackrus) | Hook for Slack chat. | -| [Stackdriver](https://github.com/knq/sdhook) | Hook for logging to [Google Stackdriver](https://cloud.google.com/logging/) | -| [Sumorus](https://github.com/doublefree/sumorus) | Hook for logging to [SumoLogic](https://www.sumologic.com/)| -| [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. | -| [TraceView](https://github.com/evalphobia/logrus_appneta) | Hook for logging to [AppNeta TraceView](https://www.appneta.com/products/traceview/) | -| [Typetalk](https://github.com/dragon3/logrus-typetalk-hook) | Hook for logging to [Typetalk](https://www.typetalk.in/) | -| [logz.io](https://github.com/ripcurld00d/logrus-logzio-hook) | Hook for logging to [logz.io](https://logz.io), a Log as a Service using Logstash | - -#### 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(&log.JSONFormatter{}) - } else { - // The TextFormatter is default, you don't actually have to do this. - log.SetFormatter(&log.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`. For Windows, see - [github.com/mattn/go-colorable](https://github.com/mattn/go-colorable). - * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#TextFormatter). -* `logrus.JSONFormatter`. Logs fields as JSON. - * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#JSONFormatter). - -Third party logging formatters: - -* [`logstash`](https://github.com/bshuster-repo/logrus-logstash-hook). Logs fields as [Logstash](http://logstash.net) Events. -* [`prefixed`](https://github.com/x-cray/logrus-prefixed-formatter). Displays log entry source along with alternative layout. -* [`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 *MyJSONFormatter) 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 -} -``` - -#### Logger as an `io.Writer` - -Logrus can be transformed into an `io.Writer`. That writer is the end of an `io.Pipe` and it is your responsibility to close it. - -```go -w := logger.Writer() -defer w.Close() - -srv := http.Server{ - // create a stdlib log.Logger that writes to - // logrus.Logger. - ErrorLog: log.New(w, "", 0), -} -``` - -Each line written to that writer will be printed the usual way, using formatters -and hooks. The level for those entries is `info`. - -This means that we can override the standard library logger easily: - -```go -logger := logrus.New() -logger.Formatter = &logrus.JSONFormatter{} - -// Use logrus for standard log output -// Note that `log` here references stdlib's log -// Not logrus imported under the name `log`. -log.SetOutput(logger.Writer()) -``` - -#### Rotation - -Log rotation is not provided with Logrus. Log rotation should be done by an -external program (like `logrotate(8)`) that can compress and delete old log -entries. It should not be a feature of the application-level logger. - -#### Tools - -| Tool | Description | -| ---- | ----------- | -|[Logrus Mate](https://github.com/gogap/logrus_mate)|Logrus mate is a tool for Logrus to manage loggers, you can initial logger's level, hook and formatter by config file, the logger will generated with different config at different environment.| -|[Logrus Viper Helper](https://github.com/heirko/go-contrib/tree/master/logrusHelper)|An Helper arround Logrus to wrap with spf13/Viper to load configuration with fangs! And to simplify Logrus configuration use some behavior of [Logrus Mate](https://github.com/gogap/logrus_mate). [sample](https://github.com/heirko/iris-contrib/blob/master/middleware/logrus-logger/example) | - -#### Testing - -Logrus has a built in facility for asserting the presence of log messages. This is implemented through the `test` hook and provides: - -* decorators for existing logger (`test.NewLocal` and `test.NewGlobal`) which basically just add the `test` hook -* a test logger (`test.NewNullLogger`) that just records log messages (and does not output any): - -```go -logger, hook := NewNullLogger() -logger.Error("Hello error") - -assert.Equal(1, len(hook.Entries)) -assert.Equal(logrus.ErrorLevel, hook.LastEntry().Level) -assert.Equal("Hello error", hook.LastEntry().Message) - -hook.Reset() -assert.Nil(hook.LastEntry()) -``` - -#### Fatal handlers - -Logrus can register one or more functions that will be called when any `fatal` -level message is logged. The registered handlers will be executed before -logrus performs a `os.Exit(1)`. This behavior may be helpful if callers need -to gracefully shutdown. Unlike a `panic("Something went wrong...")` call which can be intercepted with a deferred `recover` a call to `os.Exit(1)` can not be intercepted. - -``` -... -handler := func() { - // gracefully shutdown something... -} -logrus.RegisterExitHandler(handler) -... -``` - -#### Thread safety - -By default Logger is protected by mutex for concurrent writes, this mutex is invoked when calling hooks and writing logs. -If you are sure such locking is not needed, you can call logger.SetNoLock() to disable the locking. - -Situation when locking is not needed includes: - -* You have no hooks registered, or hooks calling is already thread-safe. - -* Writing to logger.Out is already thread-safe, for example: - - 1) logger.Out is protected by locks. - - 2) logger.Out is a os.File handler opened with `O_APPEND` flag, and every write is smaller than 4k. (This allow multi-thread/multi-process writing) - - (Refer to http://www.notthewizard.com/2014/06/17/are-files-appends-really-atomic/) |