Use logrus instead of log

src/metrics-alerting/main.go

 import (
 	"flag"
 	"fmt"
-	"log"
 
 	"metrics-alerting/alert"
 	"metrics-alerting/config"
 	"metrics-alerting/warp10"
+
+	"github.com/sirupsen/logrus"
 )
 
 var (
 		}
 
 		if err != nil {
-			log.Fatal(err)
+			logrus.Error(err)
 		}
 	}
 }

vendor/src/github.com/sirupsen/logrus/CHANGELOG.md

+# 1.0.3
+
+* Replace example files with testable examples
+
+# 1.0.2
+
+* bug: quote non-string values in text formatter (#583)
+* Make (*Logger) SetLevel a public method
+
+# 1.0.1
+
+* bug: fix escaping in text formatter (#575)
+
+# 1.0.0
+
+* Officially changed name to lower-case
+* bug: colors on Windows 10 (#541)
+* bug: fix race in accessing level (#512)
+
+# 0.11.5
+
+* feature: add writer and writerlevel to entry (#372)
+
+# 0.11.4
+
+* bug: fix undefined variable on solaris (#493)
+
+# 0.11.3
+
+* formatter: configure quoting of empty values (#484)
+* formatter: configure quoting character (default is `"`) (#484)
+* bug: fix not importing io correctly in non-linux environments (#481)
+
+# 0.11.2
+
+* bug: fix windows terminal detection (#476)
+
+# 0.11.1
+
+* bug: fix tty detection with custom out (#471)
+
+# 0.11.0
+
+* performance: Use bufferpool to allocate (#370)
+* terminal: terminal detection for app-engine (#343)
+* feature: exit handler (#375)
+
+# 0.10.0
+
+* feature: Add a test hook (#180)
+* feature: `ParseLevel` is now case-insensitive (#326)
+* feature: `FieldLogger` interface that generalizes `Logger` and `Entry` (#308)
+* performance: avoid re-allocations on `WithFields` (#335)
+
+# 0.9.0
+
+* logrus/text_formatter: don't emit empty msg
+* logrus/hooks/airbrake: move out of main repository
+* logrus/hooks/sentry: move out of main repository
+* logrus/hooks/papertrail: move out of main repository
+* logrus/hooks/bugsnag: move out of main repository
+* logrus/core: run tests with `-race`
+* logrus/core: detect TTY based on `stderr`
+* logrus/core: support `WithError` on logger
+* logrus/core: Solaris support
+
+# 0.8.7
+
+* logrus/core: fix possible race (#216)
+* logrus/doc: small typo fixes and doc improvements
+
+
+# 0.8.6
+
+* hooks/raven: allow passing an initialized client
+
+# 0.8.5
+
+* logrus/core: revert #208
+
+# 0.8.4
+
+* formatter/text: fix data race (#218)
+
+# 0.8.3
+
+* logrus/core: fix entry log level (#208)
+* logrus/core: improve performance of text formatter by 40%
+* logrus/core: expose `LevelHooks` type
+* logrus/core: add support for DragonflyBSD and NetBSD
+* formatter/text: print structs more verbosely
+
+# 0.8.2
+
+* logrus: fix more Fatal family functions
+
+# 0.8.1
+
+* logrus: fix not exiting on `Fatalf` and `Fatalln`
+
+# 0.8.0
+
+* logrus: defaults to stderr instead of stdout
+* hooks/sentry: add special field for `*http.Request`
+* formatter/text: ignore Windows for colors
+
+# 0.7.3
+
+* formatter/\*: allow configuration of timestamp layout
+
+# 0.7.2
+
+* formatter/text: Add configuration option for time format (#158)

vendor/src/github.com/sirupsen/logrus/LICENSE

+The MIT License (MIT)
+
+Copyright (c) 2014 Simon Eskildsen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

vendor/src/github.com/sirupsen/logrus/README.md

+# Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/>&nbsp;[![Build Status](https://travis-ci.org/sirupsen/logrus.svg?branch=master)](https://travis-ci.org/sirupsen/logrus)&nbsp;[![GoDoc](https://godoc.org/github.com/sirupsen/logrus?status.svg)](https://godoc.org/github.com/sirupsen/logrus)
+
+Logrus is a structured logger for Go (golang), completely API compatible with
+the standard library logger.
+
+**Seeing weird case-sensitive problems?** It's in the past been possible to
+import Logrus as both upper- and lower-case. Due to the Go package environment,
+this caused issues in the community and we needed a standard. Some environments
+experienced problems with the upper-case variant, so the lower-case was decided.
+Everything using `logrus` will need to use the lower-case:
+`github.com/sirupsen/logrus`. Any package that isn't, should be changed.
+
+To fix Glide, see [these
+comments](https://github.com/sirupsen/logrus/issues/553#issuecomment-306591437).
+For an in-depth explanation of the casing issue, see [this
+comment](https://github.com/sirupsen/logrus/issues/570#issuecomment-313933276).
+
+**Are you interested in assisting in maintaining Logrus?** Currently I have a
+lot of obligations, and I am unable to provide Logrus with the maintainership it
+needs. If you'd like to help, please reach out to me at `simon at author's
+username dot com`.
+
+Nicely color-coded in development (when a TTY is attached, otherwise just
+plain text):
+
+![Colored](http://i.imgur.com/PY7qMwd.png)
+
+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
+```
+
+#### Case-sensitivity
+
+The organization's name was changed to lower-case--and this will not be changed
+back. If you are getting import conflicts due to case sensitivity, please use
+the lower-case import: `github.com/sirupsen/logrus`.
+
+#### 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 (
+  "os"
+  "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 through 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) |
+| [AzureTableHook](https://github.com/kpfaulkner/azuretablehook/) | Hook for logging to Azure Table Storage|
+| [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 |
+| [Discordrus](https://github.com/kz/discordrus) | Hook for logging to [Discord](https://discordapp.com/) |
+| [ElasticSearch](https://github.com/sohlich/elogrus) | Hook for logging to ElasticSearch|
+| [Firehose](https://github.com/beaubrewer/logrus_firehose) | Hook for logging to [Amazon Firehose](https://aws.amazon.com/kinesis/firehose/)
+| [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/tracer0tong/kafkalogrus) | Hook for logging to Kafka |
+| [LFShook](https://github.com/rifflock/lfshook) | Hook for logging to the local filesystem |
+| [Logbeat](https://github.com/macandmia/logbeat) | Hook for logging to [Opbeat](https://opbeat.com/) |
+| [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 |
+| [Mattermost](https://github.com/shuLhan/mattermost-integration/tree/master/hooks/logrus) | Hook for logging to [Mattermost](https://mattermost.com/) |
+| [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) |
+| [Promrus](https://github.com/weaveworks/promrus) | Expose number of log messages as [Prometheus](https://prometheus.io/) metrics |
+| [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. |
+| [Syslog TLS](https://github.com/shinji62/logrus-syslog-ng) | Send errors to remote syslog server with TLS support. |
+| [Telegram](https://github.com/rossmcdonald/telegram_hook) | Hook for logging errors to [Telegram](https://telegram.org/) |
+| [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 |
+| [SQS-Hook](https://github.com/tsarpaul/logrus_sqs) | Hook for logging to [Amazon Simple Queue Service (SQS)](https://aws.amazon.com/sqs/) |
+
+#### 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:
+
+* [`FluentdFormatter`](https://github.com/joonix/log). Formats entries that can be parsed by Kubernetes and Google Container Engine.
+* [`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 around 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
+import(
+  "github.com/sirupsen/logrus"
+  "github.com/sirupsen/logrus/hooks/test"
+  "github.com/stretchr/testify/assert"
+  "testing"
+)
+
+func TestSomething(t*testing.T){
+  logger, hook := test.NewNullLogger()
+  logger.Error("Helloerror")
+
+  assert.Equal(t, 1, len(hook.Entries))
+  assert.Equal(t, logrus.ErrorLevel, hook.LastEntry().Level)
+  assert.Equal(t, "Helloerror", hook.LastEntry().Message)
+
+  hook.Reset()
+  assert.Nil(t, 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/)

vendor/src/github.com/sirupsen/logrus/alt_exit.go

+package logrus
+
+// The following code was sourced and modified from the
+// https://github.com/tebeka/atexit package governed by the following license:
+//
+// Copyright (c) 2012 Miki Tebeka <miki.tebeka@gmail.com>.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software is furnished to do so,
+// subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import (
+	"fmt"
+	"os"
+)
+
+var handlers = []func(){}
+
+func runHandler(handler func()) {
+	defer func() {
+		if err := recover(); err != nil {
+			fmt.Fprintln(os.Stderr, "Error: Logrus exit handler error:", err)
+		}
+	}()
+
+	handler()
+}
+
+func runHandlers() {
+	for _, handler := range handlers {
+		runHandler(handler)
+	}
+}
+
+// Exit runs all the Logrus atexit handlers and then terminates the program using os.Exit(code)
+func Exit(code int) {
+	runHandlers()
+	os.Exit(code)
+}
+
+// RegisterExitHandler adds a Logrus Exit handler, call logrus.Exit to invoke
+// all handlers. The handlers will also be invoked when any Fatal log entry is
+// made.
+//
+// This method is useful when a caller wishes to use logrus to log a fatal
+// message but also needs to gracefully shutdown. An example usecase could be
+// closing database connections, or sending a alert that the application is
+// closing.
+func RegisterExitHandler(handler func()) {
+	handlers = append(handlers, handler)
+}

vendor/src/github.com/sirupsen/logrus/alt_exit_test.go

+package logrus
+
+import (
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestRegister(t *testing.T) {
+	current := len(handlers)
+	RegisterExitHandler(func() {})
+	if len(handlers) != current+1 {
+		t.Fatalf("expected %d handlers, got %d", current+1, len(handlers))
+	}
+}
+
+func TestHandler(t *testing.T) {
+	tempDir, err := ioutil.TempDir("", "test_handler")
+	if err != nil {
+		log.Fatalf("can't create temp dir. %q", err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	gofile := filepath.Join(tempDir, "gofile.go")
+	if err := ioutil.WriteFile(gofile, testprog, 0666); err != nil {
+		t.Fatalf("can't create go file. %q", err)
+	}
+
+	outfile := filepath.Join(tempDir, "outfile.out")
+	arg := time.Now().UTC().String()
+	err = exec.Command("go", "run", gofile, outfile, arg).Run()
+	if err == nil {
+		t.Fatalf("completed normally, should have failed")
+	}
+
+	data, err := ioutil.ReadFile(outfile)
+	if err != nil {
+		t.Fatalf("can't read output file %s. %q", outfile, err)
+	}
+
+	if string(data) != arg {
+		t.Fatalf("bad data. Expected %q, got %q", data, arg)
+	}
+}
+
+var testprog = []byte(`
+// Test program for atexit, gets output file and data as arguments and writes
+// data to output file in atexit handler.
+package main
+
+import (
+	"github.com/sirupsen/logrus"
+	"flag"
+	"fmt"
+	"io/ioutil"
+)
+
+var outfile = ""
+var data = ""
+
+func handler() {
+	ioutil.WriteFile(outfile, []byte(data), 0666)
+}
+
+func badHandler() {
+	n := 0
+	fmt.Println(1/n)
+}
+
+func main() {
+	flag.Parse()
+	outfile = flag.Arg(0)
+	data = flag.Arg(1)
+
+	logrus.RegisterExitHandler(handler)
+	logrus.RegisterExitHandler(badHandler)
+	logrus.Fatal("Bye bye")
+}
+`)

vendor/src/github.com/sirupsen/logrus/appveyor.yml

+version: "{build}"
+platform: x64
+clone_folder: c:\gopath\src\github.com\sirupsen\logrus
+environment:  
+  GOPATH: c:\gopath
+branches:  
+  only:
+    - master
+install:  
+  - set PATH=%GOPATH%\bin;c:\go\bin;%PATH%
+  - go version
+build_script:  
+  - go get -t
+  - go test

vendor/src/github.com/sirupsen/logrus/doc.go

+/*
+Package logrus is a structured logger for Go, completely API compatible with the standard library logger.
+
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+  package main
+
+  import (
+    log "github.com/sirupsen/logrus"
+  )
+
+  func main() {
+    log.WithFields(log.Fields{
+      "animal": "walrus",
+      "number": 1,
+      "size":   10,
+    }).Info("A walrus appears")
+  }
+
+Output:
+  time="2015-09-07T08:48:33Z" level=info msg="A walrus appears" animal=walrus number=1 size=10
+
+For a full guide visit https://github.com/sirupsen/logrus
+*/
+package logrus

vendor/src/github.com/sirupsen/logrus/entry.go

+package logrus
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"sync"
+	"time"
+)
+
+var bufferPool *sync.Pool
+
+func init() {
+	bufferPool = &sync.Pool{
+		New: func() interface{} {
+			return new(bytes.Buffer)
+		},
+	}
+}
+
+// Defines the key when adding errors using WithError.
+var ErrorKey = "error"
+
+// An entry is the final or intermediate Logrus logging entry. It contains all
+// the fields passed with WithField{,s}. It's finally logged when Debug, Info,
+// Warn, Error, Fatal or Panic is called on it. These objects can be reused and
+// passed around as much as you wish to avoid field duplication.
+type Entry struct {
+	Logger *Logger
+
+	// Contains all the fields set by the user.
+	Data Fields
+
+	// Time at which the log entry was created
+	Time time.Time
+
+	// Level the log entry was logged at: Debug, Info, Warn, Error, Fatal or Panic
+	// This field will be set on entry firing and the value will be equal to the one in Logger struct field.
+	Level Level
+
+	// Message passed to Debug, Info, Warn, Error, Fatal or Panic
+	Message string
+
+	// When formatter is called in entry.log(), an Buffer may be set to entry
+	Buffer *bytes.Buffer
+}
+
+func NewEntry(logger *Logger) *Entry {
+	return &Entry{
+		Logger: logger,
+		// Default is three fields, give a little extra room
+		Data: make(Fields, 5),
+	}
+}
+
+// Returns the string representation from the reader and ultimately the
+// formatter.
+func (entry *Entry) String() (string, error) {
+	serialized, err := entry.Logger.Formatter.Format(entry)
+	if err != nil {
+		return "", err
+	}
+	str := string(serialized)
+	return str, nil
+}
+
+// Add an error as single field (using the key defined in ErrorKey) to the Entry.
+func (entry *Entry) WithError(err error) *Entry {
+	return entry.WithField(ErrorKey, err)
+}
+
+// Add a single field to the Entry.
+func (entry *Entry) WithField(key string, value interface{}) *Entry {
+	return entry.WithFields(Fields{key: value})
+}
+
+// Add a map of fields to the Entry.
+func (entry *Entry) WithFields(fields Fields) *Entry {
+	data := make(Fields, len(entry.Data)+len(fields))
+	for k, v := range entry.Data {
+		data[k] = v
+	}
+	for k, v := range fields {
+		data[k] = v
+	}
+	return &Entry{Logger: entry.Logger, Data: data}
+}
+
+// This function is not declared with a pointer value because otherwise
+// race conditions will occur when using multiple goroutines
+func (entry Entry) log(level Level, msg string) {
+	var buffer *bytes.Buffer
+	entry.Time = time.Now()
+	entry.Level = level
+	entry.Message = msg
+
+	entry.Logger.mu.Lock()
+	err := entry.Logger.Hooks.Fire(level, &entry)
+	entry.Logger.mu.Unlock()
+	if err != nil {
+		entry.Logger.mu.Lock()
+		fmt.Fprintf(os.Stderr, "Failed to fire hook: %v\n", err)
+		entry.Logger.mu.Unlock()
+	}
+	buffer = bufferPool.Get().(*bytes.Buffer)
+	buffer.Reset()
+	defer bufferPool.Put(buffer)
+	entry.Buffer = buffer
+	serialized, err := entry.Logger.Formatter.Format(&entry)
+	entry.Buffer = nil
+	if err != nil {
+		entry.Logger.mu.Lock()
+		fmt.Fprintf(os.Stderr, "Failed to obtain reader, %v\n", err)
+		entry.Logger.mu.Unlock()
+	} else {
+		entry.Logger.mu.Lock()
+		_, err = entry.Logger.Out.Write(serialized)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Failed to write to log, %v\n", err)
+		}
+		entry.Logger.mu.Unlock()
+	}
+
+	// To avoid Entry#log() returning a value that only would make sense for
+	// panic() to use in Entry#Panic(), we avoid the allocation by checking
+	// directly here.
+	if level <= PanicLevel {
+		panic(&entry)
+	}
+}
+
+func (entry *Entry) Debug(args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.log(DebugLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Print(args ...interface{}) {
+	entry.Info(args...)
+}
+
+func (entry *Entry) Info(args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.log(InfoLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Warn(args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.log(WarnLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Warning(args ...interface{}) {
+	entry.Warn(args...)
+}
+
+func (entry *Entry) Error(args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.log(ErrorLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Fatal(args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.log(FatalLevel, fmt.Sprint(args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panic(args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.log(PanicLevel, fmt.Sprint(args...))
+	}
+	panic(fmt.Sprint(args...))
+}
+
+// Entry Printf family functions
+
+func (entry *Entry) Debugf(format string, args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.Debug(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Infof(format string, args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.Info(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Printf(format string, args ...interface{}) {
+	entry.Infof(format, args...)
+}
+
+func (entry *Entry) Warnf(format string, args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.Warn(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Warningf(format string, args ...interface{}) {
+	entry.Warnf(format, args...)
+}
+
+func (entry *Entry) Errorf(format string, args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.Error(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Fatalf(format string, args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.Fatal(fmt.Sprintf(format, args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panicf(format string, args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.Panic(fmt.Sprintf(format, args...))
+	}
+}
+
+// Entry Println family functions
+
+func (entry *Entry) Debugln(args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.Debug(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Infoln(args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.Info(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Println(args ...interface{}) {
+	entry.Infoln(args...)
+}
+
+func (entry *Entry) Warnln(args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.Warn(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Warningln(args ...interface{}) {
+	entry.Warnln(args...)
+}
+
+func (entry *Entry) Errorln(args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.Error(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Fatalln(args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.Fatal(entry.sprintlnn(args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panicln(args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.Panic(entry.sprintlnn(args...))
+	}
+}
+
+// Sprintlnn => Sprint no newline. This is to get the behavior of how
+// fmt.Sprintln where spaces are always added between operands, regardless of
+// their type. Instead of vendoring the Sprintln implementation to spare a
+// string allocation, we do the simplest thing.
+func (entry *Entry) sprintlnn(args ...interface{}) string {
+	msg := fmt.Sprintln(args...)
+	return msg[:len(msg)-1]
+}

vendor/src/github.com/sirupsen/logrus/entry_test.go

+package logrus
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestEntryWithError(t *testing.T) {
+
+	assert := assert.New(t)
+
+	defer func() {
+		ErrorKey = "error"
+	}()
+
+	err := fmt.Errorf("kaboom at layer %d", 4711)
+
+	assert.Equal(err, WithError(err).Data["error"])
+
+	logger := New()
+	logger.Out = &bytes.Buffer{}
+	entry := NewEntry(logger)
+
+	assert.Equal(err, entry.WithError(err).Data["error"])
+
+	ErrorKey = "err"
+
+	assert.Equal(err, entry.WithError(err).Data["err"])
+
+}
+
+func TestEntryPanicln(t *testing.T) {
+	errBoom := fmt.Errorf("boom time")
+
+	defer func() {
+		p := recover()
+		assert.NotNil(t, p)
+
+		switch pVal := p.(type) {
+		case *Entry:
+			assert.Equal(t, "kaboom", pVal.Message)
+			assert.Equal(t, errBoom, pVal.Data["err"])
+		default:
+			t.Fatalf("want type *Entry, got %T: %#v", pVal, pVal)
+		}
+	}()
+
+	logger := New()
+	logger.Out = &bytes.Buffer{}
+	entry := NewEntry(logger)
+	entry.WithField("err", errBoom).Panicln("kaboom")
+}
+
+func TestEntryPanicf(t *testing.T) {
+	errBoom := fmt.Errorf("boom again")
+
+	defer func() {
+		p := recover()
+		assert.NotNil(t, p)
+
+		switch pVal := p.(type) {
+		case *Entry:
+			assert.Equal(t, "kaboom true", pVal.Message)
+			assert.Equal(t, errBoom, pVal.Data["err"])
+		default:
+			t.Fatalf("want type *Entry, got %T: %#v", pVal, pVal)
+		}
+	}()
+
+	logger := New()
+	logger.Out = &bytes.Buffer{}
+	entry := NewEntry(logger)
+	entry.WithField("err", errBoom).Panicf("kaboom %v", true)
+}

vendor/src/github.com/sirupsen/logrus/example_basic_test.go

+package logrus_test
+
+import (
+	"github.com/sirupsen/logrus"
+	"os"
+)
+
+func Example_basic() {
+	var log = logrus.New()
+	log.Formatter = new(logrus.JSONFormatter)
+	log.Formatter = new(logrus.TextFormatter)                     //default
+	log.Formatter.(*logrus.TextFormatter).DisableTimestamp = true // remove timestamp from test output
+	log.Level = logrus.DebugLevel
+	log.Out = os.Stdout
+
+	// 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")
+	// }
+
+	defer func() {
+		err := recover()
+		if err != nil {
+			entry := err.(*logrus.Entry)
+			log.WithFields(logrus.Fields{
+				"omg":         true,
+				"err_animal":  entry.Data["animal"],
+				"err_size":    entry.Data["size"],
+				"err_level":   entry.Level,
+				"err_message": entry.Message,
+				"number":      100,
+			}).Error("The ice breaks!") // or use Fatal() to force the process to exit with a nonzero code
+		}
+	}()
+
+	log.WithFields(logrus.Fields{
+		"animal": "walrus",
+		"number": 8,
+	}).Debug("Started observing beach")
+
+	log.WithFields(logrus.Fields{
+		"animal": "walrus",
+		"size":   10,
+	}).Info("A group of walrus emerges from the ocean")
+
+	log.WithFields(logrus.Fields{
+		"omg":    true,
+		"number": 122,
+	}).Warn("The group's number increased tremendously!")
+
+	log.WithFields(logrus.Fields{
+		"temperature": -4,
+	}).Debug("Temperature changes")
+
+	log.WithFields(logrus.Fields{
+		"animal": "orca",
+		"size":   9009,
+	}).Panic("It's over 9000!")
+
+	// Output:
+	// level=debug msg="Started observing beach" animal=walrus number=8
+	// level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10
+	// level=warning msg="The group's number increased tremendously!" number=122 omg=true
+	// level=debug msg="Temperature changes" temperature=-4
+	// level=panic msg="It's over 9000!" animal=orca size=9009
+	// level=error msg="The ice breaks!" err_animal=orca err_level=panic err_message="It's over 9000!" err_size=9009 number=100 omg=true
+}

vendor/src/github.com/sirupsen/logrus/example_hook_test.go

+package logrus_test
+
+import (
+	"github.com/sirupsen/logrus"
+	"gopkg.in/gemnasium/logrus-airbrake-hook.v2"
+	"os"
+)
+
+func Example_hook() {
+	var log = logrus.New()
+	log.Formatter = new(logrus.TextFormatter)                     // default
+	log.Formatter.(*logrus.TextFormatter).DisableTimestamp = true // remove timestamp from test output
+	log.Hooks.Add(airbrake.NewHook(123, "xyz", "development"))
+	log.Out = os.Stdout
+
+	log.WithFields(logrus.Fields{
+		"animal": "walrus",
+		"size":   10,
+	}).Info("A group of walrus emerges from the ocean")
+
+	log.WithFields(logrus.Fields{
+		"omg":    true,
+		"number": 122,
+	}).Warn("The group's number increased tremendously!")
+
+	log.WithFields(logrus.Fields{
+		"omg":    true,
+		"number": 100,
+	}).Error("The ice breaks!")
+
+	// Output:
+	// level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10
+	// level=warning msg="The group's number increased tremendously!" number=122 omg=true
+	// level=error msg="The ice breaks!" number=100 omg=true
+}

vendor/src/github.com/sirupsen/logrus/exported.go

+package logrus
+
+import (
+	"io"
+)
+
+var (
+	// std is the name of the standard logger in stdlib `log`
+	std = New()
+)
+
+func StandardLogger() *Logger {
+	return std
+}
+
+// SetOutput sets the standard logger output.
+func SetOutput(out io.Writer) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Out = out
+}
+
+// SetFormatter sets the standard logger formatter.
+func SetFormatter(formatter Formatter) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Formatter = formatter
+}
+
+// SetLevel sets the standard logger level.
+func SetLevel(level Level) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.SetLevel(level)
+}
+
+// GetLevel returns the standard logger level.
+func GetLevel() Level {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	return std.level()
+}
+
+// AddHook adds a hook to the standard logger hooks.
+func AddHook(hook Hook) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Hooks.Add(hook)
+}
+
+// WithError creates an entry from the standard logger and adds an error to it, using the value defined in ErrorKey as key.
+func WithError(err error) *Entry {
+	return std.WithField(ErrorKey, err)
+}
+
+// WithField creates an entry from the standard logger and adds a field to
+// it. If you want multiple fields, use `WithFields`.
+//
+// Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal
+// or Panic on the Entry it returns.
+func WithField(key string, value interface{}) *Entry {
+	return std.WithField(key, value)
+}
+
+// WithFields creates an entry from the standard logger and adds multiple
+// fields to it. This is simply a helper for `WithField`, invoking it
+// once for each field.
+//
+// Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal
+// or Panic on the Entry it returns.
+func WithFields(fields Fields) *Entry {
+	return std.WithFields(fields)
+}
+
+// Debug logs a message at level Debug on the standard logger.
+func Debug(args ...interface{}) {
+	std.Debug(args...)
+}
+
+// Print logs a message at level Info on the standard logger.
+func Print(args ...interface{}) {
+	std.Print(args...)
+}
+
+// Info logs a message at level Info on the standard logger.
+func Info(args ...interface{}) {
+	std.Info(args...)
+}
+
+// Warn logs a message at level Warn on the standard logger.
+func Warn(args ...interface{}) {
+	std.Warn(args...)
+}
+
+// Warning logs a message at level Warn on the standard logger.
+func Warning(args ...interface{}) {
+	std.Warning(args...)
+}
+
+// Error logs a message at level Error on the standard logger.
+func Error(args ...interface{}) {
+	std.Error(args...)
+}
+
+// Panic logs a message at level Panic on the standard logger.
+func Panic(args ...interface{}) {
+	std.Panic(args...)
+}
+
+// Fatal logs a message at level Fatal on the standard logger.
+func Fatal(args ...interface{}) {
+	std.Fatal(args...)
+}
+
+// Debugf logs a message at level Debug on the standard logger.
+func Debugf(format string, args ...interface{}) {
+	std.Debugf(format, args...)
+}
+
+// Printf logs a message at level Info on the standard logger.
+func Printf(format string, args ...interface{}) {
+	std.Printf(format, args...)
+}
+
+// Infof logs a message at level Info on the standard logger.
+func Infof(format string, args ...interface{}) {
+	std.Infof(format, args...)
+}
+
+// Warnf logs a message at level Warn on the standard logger.
+func Warnf(format string, args ...interface{}) {
+	std.Warnf(format, args...)
+}
+
+// Warningf logs a message at level Warn on the standard logger.
+func Warningf(format string, args ...interface{}) {
+	std.Warningf(format, args...)
+}
+
+// Errorf logs a message at level Error on the standard logger.
+func Errorf(format string, args ...interface{}) {
+	std.Errorf(format, args...)
+}
+
+// Panicf logs a message at level Panic on the standard logger.
+func Panicf(format string, args ...interface{}) {
+	std.Panicf(format, args...)
+}
+
+// Fatalf logs a message at level Fatal on the standard logger.
+func Fatalf(format string, args ...interface{}) {
+	std.Fatalf(format, args...)
+}
+
+// Debugln logs a message at level Debug on the standard logger.
+func Debugln(args ...interface{}) {
+	std.Debugln(args...)
+}
+
+// Println logs a message at level Info on the standard logger.
+func Println(args ...interface{}) {
+	std.Println(args...)
+}
+
+// Infoln logs a message at level Info on the standard logger.
+func Infoln(args ...interface{}) {
+	std.Infoln(args...)
+}
+
+// Warnln logs a message at level Warn on the standard logger.
+func Warnln(args ...interface{}) {
+	std.Warnln(args...)
+}
+
+// Warningln logs a message at level Warn on the standard logger.
+func Warningln(args ...interface{}) {
+	std.Warningln(args...)
+}
+
+// Errorln logs a message at level Error on the standard logger.
+func Errorln(args ...interface{}) {
+	std.Errorln(args...)
+}
+
+// Panicln logs a message at level Panic on the standard logger.
+func Panicln(args ...interface{}) {
+	std.Panicln(args...)
+}
+
+// Fatalln logs a message at level Fatal on the standard logger.
+func Fatalln(args ...interface{}) {
+	std.Fatalln(args...)
+}

vendor/src/github.com/sirupsen/logrus/formatter.go

+package logrus
+
+import "time"
+
+const defaultTimestampFormat = time.RFC3339
+
+// The Formatter interface is used to implement a custom Formatter. It takes an
+// `Entry`. It exposes all the fields, including the default ones:
+//
+// * `entry.Data["msg"]`. The message passed from Info, Warn, Error ..
+// * `entry.Data["time"]`. The timestamp.
+// * `entry.Data["level"]. The level the entry was logged at.
+//
+// Any additional fields added with `WithField` or `WithFields` are also in
+// `entry.Data`. Format is expected to return an array of bytes which are then
+// logged to `logger.Out`.
+type Formatter interface {
+	Format(*Entry) ([]byte, error)
+}
+
+// This is to not silently overwrite `time`, `msg` and `level` fields when
+// dumping it. If this code wasn't there doing:
+//
+//  logrus.WithField("level", 1).Info("hello")
+//
+// Would just silently drop the user provided level. Instead with this code
+// it'll logged as:
+//
+//  {"level": "info", "fields.level": 1, "msg": "hello", "time": "..."}
+//
+// It's not exported because it's still using Data in an opinionated way. It's to
+// avoid code duplication between the two default formatters.
+func prefixFieldClashes(data Fields) {
+	if t, ok := data["time"]; ok {
+		data["fields.time"] = t
+	}
+
+	if m, ok := data["msg"]; ok {
+		data["fields.msg"] = m
+	}
+
+	if l, ok := data["level"]; ok {
+		data["fields.level"] = l
+	}
+}

vendor/src/github.com/sirupsen/logrus/formatter_bench_test.go

+package logrus
+
+import (
+	"fmt"
+	"testing"
+	"time"
+)
+
+// smallFields is a small size data set for benchmarking
+var smallFields = Fields{
+	"foo":   "bar",
+	"baz":   "qux",
+	"one":   "two",
+	"three": "four",
+}
+
+// largeFields is a large size data set for benchmarking
+var largeFields = Fields{
+	"foo":       "bar",
+	"baz":       "qux",
+	"one":       "two",
+	"three":     "four",
+	"five":      "six",
+	"seven":     "eight",
+	"nine":      "ten",
+	"eleven":    "twelve",
+	"thirteen":  "fourteen",
+	"fifteen":   "sixteen",
+	"seventeen": "eighteen",
+	"nineteen":  "twenty",
+	"a":         "b",
+	"c":         "d",
+	"e":         "f",
+	"g":         "h",
+	"i":         "j",
+	"k":         "l",
+	"m":         "n",
+	"o":         "p",
+	"q":         "r",
+	"s":         "t",
+	"u":         "v",
+	"w":         "x",
+	"y":         "z",
+	"this":      "will",
+	"make":      "thirty",
+	"entries":   "yeah",
+}
+
+var errorFields = Fields{
+	"foo": fmt.Errorf("bar"),
+	"baz": fmt.Errorf("qux"),
+}
+
+func BenchmarkErrorTextFormatter(b *testing.B) {
+	doBenchmark(b, &TextFormatter{DisableColors: true}, errorFields)
+}
+
+func BenchmarkSmallTextFormatter(b *testing.B) {
+	doBenchmark(b, &TextFormatter{DisableColors: true}, smallFields)
+}
+
+func BenchmarkLargeTextFormatter(b *testing.B) {
+	doBenchmark(b, &TextFormatter{DisableColors: true}, largeFields)
+}
+
+func BenchmarkSmallColoredTextFormatter(b *testing.B) {
+	doBenchmark(b, &TextFormatter{ForceColors: true}, smallFields)
+}
+
+func BenchmarkLargeColoredTextFormatter(b *testing.B) {
+	doBenchmark(b, &TextFormatter{ForceColors: true}, largeFields)
+}
+
+func BenchmarkSmallJSONFormatter(b *testing.B) {
+	doBenchmark(b, &JSONFormatter{}, smallFields)
+}
+
+func BenchmarkLargeJSONFormatter(b *testing.B) {
+	doBenchmark(b, &JSONFormatter{}, largeFields)
+}
+
+func doBenchmark(b *testing.B, formatter Formatter, fields Fields) {
+	logger := New()
+
+	entry := &Entry{
+		Time:    time.Time{},
+		Level:   InfoLevel,
+		Message: "message",
+		Data:    fields,
+		Logger:  logger,
+	}
+	var d []byte
+	var err error
+	for i := 0; i < b.N; i++ {
+		d, err = formatter.Format(entry)
+		if err != nil {
+			b.Fatal(err)
+		}
+		b.SetBytes(int64(len(d)))
+	}
+}

vendor/src/github.com/sirupsen/logrus/hook_test.go

+package logrus
+
+import (
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type TestHook struct {
+	Fired bool
+}
+
+func (hook *TestHook) Fire(entry *Entry) error {
+	hook.Fired = true
+	return nil
+}
+
+func (hook *TestHook) Levels() []Level {
+	return []Level{
+		DebugLevel,
+		InfoLevel,
+		WarnLevel,
+		ErrorLevel,
+		FatalLevel,
+		PanicLevel,
+	}
+}
+
+func TestHookFires(t *testing.T) {
+	hook := new(TestHook)
+
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Hooks.Add(hook)
+		assert.Equal(t, hook.Fired, false)
+
+		log.Print("test")
+	}, func(fields Fields) {
+		assert.Equal(t, hook.Fired, true)
+	})
+}
+
+type ModifyHook struct {
+}
+
+func (hook *ModifyHook) Fire(entry *Entry) error {
+	entry.Data["wow"] = "whale"
+	return nil
+}
+
+func (hook *ModifyHook) Levels() []Level {
+	return []Level{
+		DebugLevel,
+		InfoLevel,
+		WarnLevel,
+		ErrorLevel,
+		FatalLevel,
+		PanicLevel,
+	}
+}
+
+func TestHookCanModifyEntry(t *testing.T) {
+	hook := new(ModifyHook)
+
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Hooks.Add(hook)
+		log.WithField("wow", "elephant").Print("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["wow"], "whale")
+	})
+}
+
+func TestCanFireMultipleHooks(t *testing.T) {
+	hook1 := new(ModifyHook)
+	hook2 := new(TestHook)
+
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Hooks.Add(hook1)
+		log.Hooks.Add(hook2)
+
+		log.WithField("wow", "elephant").Print("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["wow"], "whale")
+		assert.Equal(t, hook2.Fired, true)
+	})
+}
+
+type ErrorHook struct {
+	Fired bool
+}
+
+func (hook *ErrorHook) Fire(entry *Entry) error {
+	hook.Fired = true
+	return nil
+}
+
+func (hook *ErrorHook) Levels() []Level {
+	return []Level{
+		ErrorLevel,
+	}
+}
+
+func TestErrorHookShouldntFireOnInfo(t *testing.T) {
+	hook := new(ErrorHook)
+
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Hooks.Add(hook)
+		log.Info("test")
+	}, func(fields Fields) {
+		assert.Equal(t, hook.Fired, false)
+	})
+}
+
+func TestErrorHookShouldFireOnError(t *testing.T) {
+	hook := new(ErrorHook)
+
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Hooks.Add(hook)
+		log.Error("test")
+	}, func(fields Fields) {
+		assert.Equal(t, hook.Fired, true)
+	})
+}
+
+func TestAddHookRace(t *testing.T) {
+	var wg sync.WaitGroup
+	wg.Add(2)
+	hook := new(ErrorHook)
+	LogAndAssertJSON(t, func(log *Logger) {
+		go func() {
+			defer wg.Done()
+			log.AddHook(hook)
+		}()
+		go func() {
+			defer wg.Done()
+			log.Error("test")
+		}()
+		wg.Wait()
+	}, func(fields Fields) {
+		// the line may have been logged
+		// before the hook was added, so we can't
+		// actually assert on the hook
+	})
+}

vendor/src/github.com/sirupsen/logrus/hooks.go

+package logrus
+
+// A hook to be fired when logging on the logging levels returned from
+// `Levels()` on your implementation of the interface. Note that this is not
+// fired in a goroutine or a channel with workers, you should handle such
+// functionality yourself if your call is non-blocking and you don't wish for
+// the logging calls for levels returned from `Levels()` to block.
+type Hook interface {
+	Levels() []Level
+	Fire(*Entry) error
+}
+
+// Internal type for storing the hooks on a logger instance.
+type LevelHooks map[Level][]Hook
+
+// Add a hook to an instance of logger. This is called with
+// `log.Hooks.Add(new(MyHook))` where `MyHook` implements the `Hook` interface.
+func (hooks LevelHooks) Add(hook Hook) {
+	for _, level := range hook.Levels() {
+		hooks[level] = append(hooks[level], hook)
+	}
+}
+
+// Fire all the hooks for the passed level. Used by `entry.log` to fire
+// appropriate hooks for a log entry.
+func (hooks LevelHooks) Fire(level Level, entry *Entry) error {
+	for _, hook := range hooks[level] {
+		if err := hook.Fire(entry); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

vendor/src/github.com/sirupsen/logrus/hooks/syslog/README.md

+# Syslog Hooks for Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/>
+
+## Usage
+
+```go
+import (
+  "log/syslog"
+  "github.com/sirupsen/logrus"
+  lSyslog "github.com/sirupsen/logrus/hooks/syslog"
+)
+
+func main() {
+  log       := logrus.New()
+  hook, err := lSyslog.NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "")
+
+  if err == nil {
+    log.Hooks.Add(hook)
+  }
+}
+```
+
+If you want to connect to local syslog (Ex. "/dev/log" or "/var/run/syslog" or "/var/run/log"). Just assign empty string to the first two parameters of `NewSyslogHook`. It should look like the following.
+
+```go
+import (
+  "log/syslog"
+  "github.com/sirupsen/logrus"
+  lSyslog "github.com/sirupsen/logrus/hooks/syslog"
+)
+
+func main() {
+  log       := logrus.New()
+  hook, err := lSyslog.NewSyslogHook("", "", syslog.LOG_INFO, "")
+
+  if err == nil {
+    log.Hooks.Add(hook)
+  }
+}
+```

vendor/src/github.com/sirupsen/logrus/hooks/syslog/syslog.go

+// +build !windows,!nacl,!plan9
+
+package syslog
+
+import (
+	"fmt"
+	"log/syslog"
+	"os"
+
+	"github.com/sirupsen/logrus"
+)
+
+// SyslogHook to send logs via syslog.
+type SyslogHook struct {
+	Writer        *syslog.Writer
+	SyslogNetwork string
+	SyslogRaddr   string
+}
+
+// Creates a hook to be added to an instance of logger. This is called with
+// `hook, err := NewSyslogHook("udp", "localhost:514", syslog.LOG_DEBUG, "")`
+// `if err == nil { log.Hooks.Add(hook) }`
+func NewSyslogHook(network, raddr string, priority syslog.Priority, tag string) (*SyslogHook, error) {
+	w, err := syslog.Dial(network, raddr, priority, tag)
+	return &SyslogHook{w, network, raddr}, err
+}
+
+func (hook *SyslogHook) Fire(entry *logrus.Entry) error {
+	line, err := entry.String()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Unable to read entry, %v", err)
+		return err
+	}
+
+	switch entry.Level {
+	case logrus.PanicLevel:
+		return hook.Writer.Crit(line)
+	case logrus.FatalLevel:
+		return hook.Writer.Crit(line)
+	case logrus.ErrorLevel:
+		return hook.Writer.Err(line)
+	case logrus.WarnLevel:
+		return hook.Writer.Warning(line)
+	case logrus.InfoLevel:
+		return hook.Writer.Info(line)
+	case logrus.DebugLevel:
+		return hook.Writer.Debug(line)
+	default:
+		return nil
+	}
+}
+
+func (hook *SyslogHook) Levels() []logrus.Level {
+	return logrus.AllLevels
+}

vendor/src/github.com/sirupsen/logrus/hooks/syslog/syslog_test.go

+package syslog
+
+import (
+	"log/syslog"
+	"testing"
+
+	"github.com/sirupsen/logrus"
+)
+
+func TestLocalhostAddAndPrint(t *testing.T) {
+	log := logrus.New()
+	hook, err := NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "")
+
+	if err != nil {
+		t.Errorf("Unable to connect to local syslog.")
+	}
+
+	log.Hooks.Add(hook)
+
+	for _, level := range hook.Levels() {
+		if len(log.Hooks[level]) != 1 {
+			t.Errorf("SyslogHook was not added. The length of log.Hooks[%v]: %v", level, len(log.Hooks[level]))
+		}
+	}
+
+	log.Info("Congratulations!")
+}

vendor/src/github.com/sirupsen/logrus/hooks/test/test.go

+// The Test package is used for testing logrus. It is here for backwards
+// compatibility from when logrus' organization was upper-case. Please use
+// lower-case logrus and the `null` package instead of this one.
+package test
+
+import (
+	"io/ioutil"
+	"sync"
+
+	"github.com/sirupsen/logrus"
+)
+
+// Hook is a hook designed for dealing with logs in test scenarios.
+type Hook struct {
+	// Entries is an array of all entries that have been received by this hook.
+	// For safe access, use the AllEntries() method, rather than reading this
+	// value directly.
+	Entries []*logrus.Entry
+	mu      sync.RWMutex
+}
+
+// NewGlobal installs a test hook for the global logger.
+func NewGlobal() *Hook {
+
+	hook := new(Hook)
+	logrus.AddHook(hook)
+
+	return hook
+
+}
+
+// NewLocal installs a test hook for a given local logger.
+func NewLocal(logger *logrus.Logger) *Hook {
+
+	hook := new(Hook)
+	logger.Hooks.Add(hook)
+
+	return hook
+
+}
+
+// NewNullLogger creates a discarding logger and installs the test hook.
+func NewNullLogger() (*logrus.Logger, *Hook) {
+
+	logger := logrus.New()
+	logger.Out = ioutil.Discard
+
+	return logger, NewLocal(logger)
+
+}
+
+func (t *Hook) Fire(e *logrus.Entry) error {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	t.Entries = append(t.Entries, e)
+	return nil
+}
+
+func (t *Hook) Levels() []logrus.Level {
+	return logrus.AllLevels
+}
+
+// LastEntry returns the last entry that was logged or nil.
+func (t *Hook) LastEntry() *logrus.Entry {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
+	i := len(t.Entries) - 1
+	if i < 0 {
+		return nil
+	}
+	// Make a copy, for safety
+	e := *t.Entries[i]
+	return &e
+}
+
+// AllEntries returns all entries that were logged.
+func (t *Hook) AllEntries() []*logrus.Entry {
+	t.mu.RLock()
+	defer t.mu.RUnlock()
+	// Make a copy so the returned value won't race with future log requests
+	entries := make([]*logrus.Entry, len(t.Entries))
+	for i, entry := range t.Entries {
+		// Make a copy, for safety
+		e := *entry
+		entries[i] = &e
+	}
+	return entries
+}
+
+// Reset removes all Entries from this test hook.
+func (t *Hook) Reset() {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	t.Entries = make([]*logrus.Entry, 0)
+}

vendor/src/github.com/sirupsen/logrus/hooks/test/test_test.go

+package test
+
+import (
+	"testing"
+
+	"github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAllHooks(t *testing.T) {
+
+	assert := assert.New(t)
+
+	logger, hook := NewNullLogger()
+	assert.Nil(hook.LastEntry())
+	assert.Equal(0, len(hook.Entries))
+
+	logger.Error("Hello error")
+	assert.Equal(logrus.ErrorLevel, hook.LastEntry().Level)
+	assert.Equal("Hello error", hook.LastEntry().Message)
+	assert.Equal(1, len(hook.Entries))
+
+	logger.Warn("Hello warning")
+	assert.Equal(logrus.WarnLevel, hook.LastEntry().Level)
+	assert.Equal("Hello warning", hook.LastEntry().Message)
+	assert.Equal(2, len(hook.Entries))
+
+	hook.Reset()
+	assert.Nil(hook.LastEntry())
+	assert.Equal(0, len(hook.Entries))
+
+	hook = NewGlobal()
+
+	logrus.Error("Hello error")
+	assert.Equal(logrus.ErrorLevel, hook.LastEntry().Level)
+	assert.Equal("Hello error", hook.LastEntry().Message)
+	assert.Equal(1, len(hook.Entries))
+
+}

vendor/src/github.com/sirupsen/logrus/json_formatter.go

+package logrus
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+type fieldKey string
+
+// FieldMap allows customization of the key names for default fields.
+type FieldMap map[fieldKey]string
+
+// Default key names for the default fields
+const (
+	FieldKeyMsg   = "msg"
+	FieldKeyLevel = "level"
+	FieldKeyTime  = "time"
+)
+
+func (f FieldMap) resolve(key fieldKey) string {
+	if k, ok := f[key]; ok {
+		return k
+	}
+
+	return string(key)
+}
+
+// JSONFormatter formats logs into parsable json
+type JSONFormatter struct {
+	// TimestampFormat sets the format used for marshaling timestamps.
+	TimestampFormat string
+
+	// DisableTimestamp allows disabling automatic timestamps in output
+	DisableTimestamp bool
+
+	// FieldMap allows users to customize the names of keys for default fields.
+	// As an example:
+	// formatter := &JSONFormatter{
+	//   	FieldMap: FieldMap{
+	// 		 FieldKeyTime: "@timestamp",
+	// 		 FieldKeyLevel: "@level",
+	// 		 FieldKeyMsg: "@message",
+	//    },
+	// }
+	FieldMap FieldMap
+}
+
+// Format renders a single log entry
+func (f *JSONFormatter) Format(entry *Entry) ([]byte, error) {
+	data := make(Fields, len(entry.Data)+3)
+	for k, v := range entry.Data {
+		switch v := v.(type) {
+		case error:
+			// Otherwise errors are ignored by `encoding/json`
+			// https://github.com/sirupsen/logrus/issues/137
+			data[k] = v.Error()
+		default:
+			data[k] = v
+		}
+	}
+	prefixFieldClashes(data)
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = defaultTimestampFormat
+	}
+
+	if !f.DisableTimestamp {
+		data[f.FieldMap.resolve(FieldKeyTime)] = entry.Time.Format(timestampFormat)
+	}
+	data[f.FieldMap.resolve(FieldKeyMsg)] = entry.Message
+	data[f.FieldMap.resolve(FieldKeyLevel)] = entry.Level.String()
+
+	serialized, err := json.Marshal(data)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
+	}
+	return append(serialized, '\n'), nil
+}

vendor/src/github.com/sirupsen/logrus/json_formatter_test.go

+package logrus
+
+import (
+	"encoding/json"
+	"errors"
+	"strings"
+	"testing"
+)
+
+func TestErrorNotLost(t *testing.T) {
+	formatter := &JSONFormatter{}
+
+	b, err := formatter.Format(WithField("error", errors.New("wild walrus")))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+
+	entry := make(map[string]interface{})
+	err = json.Unmarshal(b, &entry)
+	if err != nil {
+		t.Fatal("Unable to unmarshal formatted entry: ", err)
+	}
+
+	if entry["error"] != "wild walrus" {
+		t.Fatal("Error field not set")
+	}
+}
+
+func TestErrorNotLostOnFieldNotNamedError(t *testing.T) {
+	formatter := &JSONFormatter{}
+
+	b, err := formatter.Format(WithField("omg", errors.New("wild walrus")))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+
+	entry := make(map[string]interface{})
+	err = json.Unmarshal(b, &entry)
+	if err != nil {
+		t.Fatal("Unable to unmarshal formatted entry: ", err)
+	}
+
+	if entry["omg"] != "wild walrus" {
+		t.Fatal("Error field not set")
+	}
+}
+
+func TestFieldClashWithTime(t *testing.T) {
+	formatter := &JSONFormatter{}
+
+	b, err := formatter.Format(WithField("time", "right now!"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+
+	entry := make(map[string]interface{})
+	err = json.Unmarshal(b, &entry)
+	if err != nil {
+		t.Fatal("Unable to unmarshal formatted entry: ", err)
+	}
+
+	if entry["fields.time"] != "right now!" {
+		t.Fatal("fields.time not set to original time field")
+	}
+
+	if entry["time"] != "0001-01-01T00:00:00Z" {
+		t.Fatal("time field not set to current time, was: ", entry["time"])
+	}
+}
+
+func TestFieldClashWithMsg(t *testing.T) {
+	formatter := &JSONFormatter{}
+
+	b, err := formatter.Format(WithField("msg", "something"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+
+	entry := make(map[string]interface{})
+	err = json.Unmarshal(b, &entry)
+	if err != nil {
+		t.Fatal("Unable to unmarshal formatted entry: ", err)
+	}
+
+	if entry["fields.msg"] != "something" {
+		t.Fatal("fields.msg not set to original msg field")
+	}
+}
+
+func TestFieldClashWithLevel(t *testing.T) {
+	formatter := &JSONFormatter{}
+
+	b, err := formatter.Format(WithField("level", "something"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+
+	entry := make(map[string]interface{})
+	err = json.Unmarshal(b, &entry)
+	if err != nil {
+		t.Fatal("Unable to unmarshal formatted entry: ", err)
+	}
+
+	if entry["fields.level"] != "something" {
+		t.Fatal("fields.level not set to original level field")
+	}
+}
+
+func TestJSONEntryEndsWithNewline(t *testing.T) {
+	formatter := &JSONFormatter{}
+
+	b, err := formatter.Format(WithField("level", "something"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+
+	if b[len(b)-1] != '\n' {
+		t.Fatal("Expected JSON log entry to end with a newline")
+	}
+}
+
+func TestJSONMessageKey(t *testing.T) {
+	formatter := &JSONFormatter{
+		FieldMap: FieldMap{
+			FieldKeyMsg: "message",
+		},
+	}
+
+	b, err := formatter.Format(&Entry{Message: "oh hai"})
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+	s := string(b)
+	if !(strings.Contains(s, "message") && strings.Contains(s, "oh hai")) {
+		t.Fatal("Expected JSON to format message key")
+	}
+}
+
+func TestJSONLevelKey(t *testing.T) {
+	formatter := &JSONFormatter{
+		FieldMap: FieldMap{
+			FieldKeyLevel: "somelevel",
+		},
+	}
+
+	b, err := formatter.Format(WithField("level", "something"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+	s := string(b)
+	if !strings.Contains(s, "somelevel") {
+		t.Fatal("Expected JSON to format level key")
+	}
+}
+
+func TestJSONTimeKey(t *testing.T) {
+	formatter := &JSONFormatter{
+		FieldMap: FieldMap{
+			FieldKeyTime: "timeywimey",
+		},
+	}
+
+	b, err := formatter.Format(WithField("level", "something"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+	s := string(b)
+	if !strings.Contains(s, "timeywimey") {
+		t.Fatal("Expected JSON to format time key")
+	}
+}
+
+func TestJSONDisableTimestamp(t *testing.T) {
+	formatter := &JSONFormatter{
+		DisableTimestamp: true,
+	}
+
+	b, err := formatter.Format(WithField("level", "something"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+	s := string(b)
+	if strings.Contains(s, FieldKeyTime) {
+		t.Error("Did not prevent timestamp", s)
+	}
+}
+
+func TestJSONEnableTimestamp(t *testing.T) {
+	formatter := &JSONFormatter{}
+
+	b, err := formatter.Format(WithField("level", "something"))
+	if err != nil {
+		t.Fatal("Unable to format entry: ", err)
+	}
+	s := string(b)
+	if !strings.Contains(s, FieldKeyTime) {
+		t.Error("Timestamp not present", s)
+	}
+}

vendor/src/github.com/sirupsen/logrus/logger.go

+package logrus
+
+import (
+	"io"
+	"os"
+	"sync"
+	"sync/atomic"
+)
+
+type Logger struct {
+	// The logs are `io.Copy`'d to this in a mutex. It's common to set this to a
+	// file, or leave it default which is `os.Stderr`. You can also set this to
+	// something more adventorous, such as logging to Kafka.
+	Out io.Writer
+	// Hooks for the logger instance. These allow firing events based on logging
+	// levels and log entries. For example, to send errors to an error tracking
+	// service, log to StatsD or dump the core on fatal errors.
+	Hooks LevelHooks
+	// All log entries pass through the formatter before logged to Out. The
+	// included formatters are `TextFormatter` and `JSONFormatter` for which
+	// TextFormatter is the default. In development (when a TTY is attached) it
+	// logs with colors, but to a file it wouldn't. You can easily implement your
+	// own that implements the `Formatter` interface, see the `README` or included
+	// formatters for examples.
+	Formatter Formatter
+	// The logging level the logger should log at. This is typically (and defaults
+	// to) `logrus.Info`, which allows Info(), Warn(), Error() and Fatal() to be
+	// logged.
+	Level Level
+	// Used to sync writing to the log. Locking is enabled by Default
+	mu MutexWrap
+	// Reusable empty entry
+	entryPool sync.Pool
+}
+
+type MutexWrap struct {
+	lock     sync.Mutex
+	disabled bool
+}
+
+func (mw *MutexWrap) Lock() {
+	if !mw.disabled {
+		mw.lock.Lock()
+	}
+}
+
+func (mw *MutexWrap) Unlock() {
+	if !mw.disabled {
+		mw.lock.Unlock()
+	}
+}
+
+func (mw *MutexWrap) Disable() {
+	mw.disabled = true
+}
+
+// Creates a new logger. Configuration should be set by changing `Formatter`,
+// `Out` and `Hooks` directly on the default logger instance. You can also just
+// instantiate your own:
+//
+//    var log = &Logger{
+//      Out: os.Stderr,
+//      Formatter: new(JSONFormatter),
+//      Hooks: make(LevelHooks),
+//      Level: logrus.DebugLevel,
+//    }
+//
+// It's recommended to make this a global instance called `log`.
+func New() *Logger {
+	return &Logger{
+		Out:       os.Stderr,
+		Formatter: new(TextFormatter),
+		Hooks:     make(LevelHooks),
+		Level:     InfoLevel,
+	}
+}
+
+func (logger *Logger) newEntry() *Entry {
+	entry, ok := logger.entryPool.Get().(*Entry)
+	if ok {
+		return entry
+	}
+	return NewEntry(logger)
+}
+
+func (logger *Logger) releaseEntry(entry *Entry) {
+	logger.entryPool.Put(entry)
+}
+
+// Adds a field to the log entry, note that it doesn't log until you call
+// Debug, Print, Info, Warn, Fatal or Panic. It only creates a log entry.
+// If you want multiple fields, use `WithFields`.
+func (logger *Logger) WithField(key string, value interface{}) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithField(key, value)
+}
+
+// Adds a struct of fields to the log entry. All it does is call `WithField` for
+// each `Field`.
+func (logger *Logger) WithFields(fields Fields) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithFields(fields)
+}
+
+// Add an error as single field to the log entry.  All it does is call
+// `WithError` for the given `error`.
+func (logger *Logger) WithError(err error) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithError(err)
+}
+
+func (logger *Logger) Debugf(format string, args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debugf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Infof(format string, args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Infof(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Printf(format string, args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Printf(format, args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warnf(format string, args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warningf(format string, args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Errorf(format string, args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Errorf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatalf(format string, args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatalf(format, args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panicf(format string, args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panicf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Debug(args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debug(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Info(args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Info(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Print(args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Info(args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warn(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warn(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warning(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warn(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Error(args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Error(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatal(args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatal(args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panic(args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panic(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Debugln(args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debugln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Infoln(args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Infoln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Println(args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Println(args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warnln(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warningln(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Errorln(args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Errorln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatalln(args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatalln(args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panicln(args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panicln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+//When file is opened with appending mode, it's safe to
+//write concurrently to a file (within 4k message on Linux).
+//In these cases user can choose to disable the lock.
+func (logger *Logger) SetNoLock() {
+	logger.mu.Disable()
+}
+
+func (logger *Logger) level() Level {
+	return Level(atomic.LoadUint32((*uint32)(&logger.Level)))
+}
+
+func (logger *Logger) SetLevel(level Level) {
+	atomic.StoreUint32((*uint32)(&logger.Level), uint32(level))
+}
+
+func (logger *Logger) AddHook(hook Hook) {
+	logger.mu.Lock()
+	defer logger.mu.Unlock()
+	logger.Hooks.Add(hook)
+}

vendor/src/github.com/sirupsen/logrus/logger_bench_test.go

+package logrus
+
+import (
+	"os"
+	"testing"
+)
+
+// smallFields is a small size data set for benchmarking
+var loggerFields = Fields{
+	"foo":   "bar",
+	"baz":   "qux",
+	"one":   "two",
+	"three": "four",
+}
+
+func BenchmarkDummyLogger(b *testing.B) {
+	nullf, err := os.OpenFile("/dev/null", os.O_WRONLY, 0666)
+	if err != nil {
+		b.Fatalf("%v", err)
+	}
+	defer nullf.Close()
+	doLoggerBenchmark(b, nullf, &TextFormatter{DisableColors: true}, smallFields)
+}
+
+func BenchmarkDummyLoggerNoLock(b *testing.B) {
+	nullf, err := os.OpenFile("/dev/null", os.O_WRONLY|os.O_APPEND, 0666)
+	if err != nil {
+		b.Fatalf("%v", err)
+	}
+	defer nullf.Close()
+	doLoggerBenchmarkNoLock(b, nullf, &TextFormatter{DisableColors: true}, smallFields)
+}
+
+func doLoggerBenchmark(b *testing.B, out *os.File, formatter Formatter, fields Fields) {
+	logger := Logger{
+		Out:       out,
+		Level:     InfoLevel,
+		Formatter: formatter,
+	}
+	entry := logger.WithFields(fields)
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			entry.Info("aaa")
+		}
+	})
+}
+
+func doLoggerBenchmarkNoLock(b *testing.B, out *os.File, formatter Formatter, fields Fields) {
+	logger := Logger{
+		Out:       out,
+		Level:     InfoLevel,
+		Formatter: formatter,
+	}
+	logger.SetNoLock()
+	entry := logger.WithFields(fields)
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			entry.Info("aaa")
+		}
+	})
+}

vendor/src/github.com/sirupsen/logrus/logrus.go

+package logrus
+
+import (
+	"fmt"
+	"log"
+	"strings"
+)
+
+// Fields type, used to pass to `WithFields`.
+type Fields map[string]interface{}
+
+// Level type
+type Level uint32
+
+// Convert the Level to a string. E.g. PanicLevel becomes "panic".
+func (level Level) String() string {
+	switch level {
+	case DebugLevel:
+		return "debug"
+	case InfoLevel:
+		return "info"
+	case WarnLevel:
+		return "warning"
+	case ErrorLevel:
+		return "error"
+	case FatalLevel:
+		return "fatal"
+	case PanicLevel:
+		return "panic"
+	}
+
+	return "unknown"
+}
+
+// ParseLevel takes a string level and returns the Logrus log level constant.
+func ParseLevel(lvl string) (Level, error) {
+	switch strings.ToLower(lvl) {
+	case "panic":
+		return PanicLevel, nil
+	case "fatal":
+		return FatalLevel, nil
+	case "error":
+		return ErrorLevel, nil
+	case "warn", "warning":
+		return WarnLevel, nil
+	case "info":
+		return InfoLevel, nil
+	case "debug":
+		return DebugLevel, nil
+	}
+
+	var l Level
+	return l, fmt.Errorf("not a valid logrus Level: %q", lvl)
+}
+
+// A constant exposing all logging levels
+var AllLevels = []Level{
+	PanicLevel,
+	FatalLevel,
+	ErrorLevel,
+	WarnLevel,
+	InfoLevel,
+	DebugLevel,
+}
+
+// These are the different logging levels. You can set the logging level to log
+// on your instance of logger, obtained with `logrus.New()`.
+const (
+	// PanicLevel level, highest level of severity. Logs and then calls panic with the
+	// message passed to Debug, Info, ...
+	PanicLevel Level = iota
+	// FatalLevel level. Logs and then calls `os.Exit(1)`. It will exit even if the
+	// logging level is set to Panic.
+	FatalLevel
+	// ErrorLevel level. Logs. Used for errors that should definitely be noted.
+	// Commonly used for hooks to send errors to an error tracking service.
+	ErrorLevel
+	// WarnLevel level. Non-critical entries that deserve eyes.
+	WarnLevel
+	// InfoLevel level. General operational entries about what's going on inside the
+	// application.
+	InfoLevel
+	// DebugLevel level. Usually only enabled when debugging. Very verbose logging.
+	DebugLevel
+)
+
+// Won't compile if StdLogger can't be realized by a log.Logger
+var (
+	_ StdLogger = &log.Logger{}
+	_ StdLogger = &Entry{}
+	_ StdLogger = &Logger{}
+)
+
+// StdLogger is what your logrus-enabled library should take, that way
+// it'll accept a stdlib logger and a logrus logger. There's no standard
+// interface, this is the closest we get, unfortunately.
+type StdLogger interface {
+	Print(...interface{})
+	Printf(string, ...interface{})
+	Println(...interface{})
+
+	Fatal(...interface{})
+	Fatalf(string, ...interface{})
+	Fatalln(...interface{})
+
+	Panic(...interface{})
+	Panicf(string, ...interface{})
+	Panicln(...interface{})
+}
+
+// The FieldLogger interface generalizes the Entry and Logger types
+type FieldLogger interface {
+	WithField(key string, value interface{}) *Entry
+	WithFields(fields Fields) *Entry
+	WithError(err error) *Entry
+
+	Debugf(format string, args ...interface{})
+	Infof(format string, args ...interface{})
+	Printf(format string, args ...interface{})
+	Warnf(format string, args ...interface{})
+	Warningf(format string, args ...interface{})
+	Errorf(format string, args ...interface{})
+	Fatalf(format string, args ...interface{})
+	Panicf(format string, args ...interface{})
+
+	Debug(args ...interface{})
+	Info(args ...interface{})
+	Print(args ...interface{})
+	Warn(args ...interface{})
+	Warning(args ...interface{})
+	Error(args ...interface{})
+	Fatal(args ...interface{})
+	Panic(args ...interface{})
+
+	Debugln(args ...interface{})
+	Infoln(args ...interface{})
+	Println(args ...interface{})
+	Warnln(args ...interface{})
+	Warningln(args ...interface{})
+	Errorln(args ...interface{})
+	Fatalln(args ...interface{})
+	Panicln(args ...interface{})
+}

vendor/src/github.com/sirupsen/logrus/logrus_test.go

+package logrus
+
+import (
+	"bytes"
+	"encoding/json"
+	"strconv"
+	"strings"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func LogAndAssertJSON(t *testing.T, log func(*Logger), assertions func(fields Fields)) {
+	var buffer bytes.Buffer
+	var fields Fields
+
+	logger := New()
+	logger.Out = &buffer
+	logger.Formatter = new(JSONFormatter)
+
+	log(logger)
+
+	err := json.Unmarshal(buffer.Bytes(), &fields)
+	assert.Nil(t, err)
+
+	assertions(fields)
+}
+
+func LogAndAssertText(t *testing.T, log func(*Logger), assertions func(fields map[string]string)) {
+	var buffer bytes.Buffer
+
+	logger := New()
+	logger.Out = &buffer
+	logger.Formatter = &TextFormatter{
+		DisableColors: true,
+	}
+
+	log(logger)
+
+	fields := make(map[string]string)
+	for _, kv := range strings.Split(buffer.String(), " ") {
+		if !strings.Contains(kv, "=") {
+			continue
+		}
+		kvArr := strings.Split(kv, "=")
+		key := strings.TrimSpace(kvArr[0])
+		val := kvArr[1]
+		if kvArr[1][0] == '"' {
+			var err error
+			val, err = strconv.Unquote(val)
+			assert.NoError(t, err)
+		}
+		fields[key] = val
+	}
+	assertions(fields)
+}
+
+func TestPrint(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Print("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test")
+		assert.Equal(t, fields["level"], "info")
+	})
+}
+
+func TestInfo(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Info("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test")
+		assert.Equal(t, fields["level"], "info")
+	})
+}
+
+func TestWarn(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Warn("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test")
+		assert.Equal(t, fields["level"], "warning")
+	})
+}
+
+func TestInfolnShouldAddSpacesBetweenStrings(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Infoln("test", "test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test test")
+	})
+}
+
+func TestInfolnShouldAddSpacesBetweenStringAndNonstring(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Infoln("test", 10)
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test 10")
+	})
+}
+
+func TestInfolnShouldAddSpacesBetweenTwoNonStrings(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Infoln(10, 10)
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "10 10")
+	})
+}
+
+func TestInfoShouldAddSpacesBetweenTwoNonStrings(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Infoln(10, 10)
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "10 10")
+	})
+}
+
+func TestInfoShouldNotAddSpacesBetweenStringAndNonstring(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Info("test", 10)
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test10")
+	})
+}
+
+func TestInfoShouldNotAddSpacesBetweenStrings(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.Info("test", "test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "testtest")
+	})
+}
+
+func TestWithFieldsShouldAllowAssignments(t *testing.T) {
+	var buffer bytes.Buffer
+	var fields Fields
+
+	logger := New()
+	logger.Out = &buffer
+	logger.Formatter = new(JSONFormatter)
+
+	localLog := logger.WithFields(Fields{
+		"key1": "value1",
+	})
+
+	localLog.WithField("key2", "value2").Info("test")
+	err := json.Unmarshal(buffer.Bytes(), &fields)
+	assert.Nil(t, err)
+
+	assert.Equal(t, "value2", fields["key2"])
+	assert.Equal(t, "value1", fields["key1"])
+
+	buffer = bytes.Buffer{}
+	fields = Fields{}
+	localLog.Info("test")
+	err = json.Unmarshal(buffer.Bytes(), &fields)
+	assert.Nil(t, err)
+
+	_, ok := fields["key2"]
+	assert.Equal(t, false, ok)
+	assert.Equal(t, "value1", fields["key1"])
+}
+
+func TestUserSuppliedFieldDoesNotOverwriteDefaults(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.WithField("msg", "hello").Info("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test")
+	})
+}
+
+func TestUserSuppliedMsgFieldHasPrefix(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.WithField("msg", "hello").Info("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["msg"], "test")
+		assert.Equal(t, fields["fields.msg"], "hello")
+	})
+}
+
+func TestUserSuppliedTimeFieldHasPrefix(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.WithField("time", "hello").Info("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["fields.time"], "hello")
+	})
+}
+
+func TestUserSuppliedLevelFieldHasPrefix(t *testing.T) {
+	LogAndAssertJSON(t, func(log *Logger) {
+		log.WithField("level", 1).Info("test")
+	}, func(fields Fields) {
+		assert.Equal(t, fields["level"], "info")
+		assert.Equal(t, fields["fields.level"], 1.0) // JSON has floats only
+	})
+}
+
+func TestDefaultFieldsAreNotPrefixed(t *testing.T) {
+	LogAndAssertText(t, func(log *Logger) {
+		ll := log.WithField("herp", "derp")
+		ll.Info("hello")
+		ll.Info("bye")
+	}, func(fields map[string]string) {
+		for _, fieldName := range []string{"fields.level", "fields.time", "fields.msg"} {
+			if _, ok := fields[fieldName]; ok {
+				t.Fatalf("should not have prefixed %q: %v", fieldName, fields)
+			}
+		}
+	})
+}
+
+func TestDoubleLoggingDoesntPrefixPreviousFields(t *testing.T) {
+
+	var buffer bytes.Buffer
+	var fields Fields
+
+	logger := New()
+	logger.Out = &buffer
+	logger.Formatter = new(JSONFormatter)
+
+	llog := logger.WithField("context", "eating raw fish")
+
+	llog.Info("looks delicious")
+
+	err := json.Unmarshal(buffer.Bytes(), &fields)
+	assert.NoError(t, err, "should have decoded first message")
+	assert.Equal(t, len(fields), 4, "should only have msg/time/level/context fields")
+	assert.Equal(t, fields["msg"], "looks delicious")
+	assert.Equal(t, fields["context"], "eating raw fish")
+
+	buffer.Reset()
+
+	llog.Warn("omg it is!")
+
+	err = json.Unmarshal(buffer.Bytes(), &fields)
+	assert.NoError(t, err, "should have decoded second message")
+	assert.Equal(t, len(fields), 4, "should only have msg/time/level/context fields")
+	assert.Equal(t, fields["msg"], "omg it is!")
+	assert.Equal(t, fields["context"], "eating raw fish")
+	assert.Nil(t, fields["fields.msg"], "should not have prefixed previous `msg` entry")
+
+}
+
+func TestConvertLevelToString(t *testing.T) {
+	assert.Equal(t, "debug", DebugLevel.String())
+	assert.Equal(t, "info", InfoLevel.String())
+	assert.Equal(t, "warning", WarnLevel.String())
+	assert.Equal(t, "error", ErrorLevel.String())
+	assert.Equal(t, "fatal", FatalLevel.String())
+	assert.Equal(t, "panic", PanicLevel.String())
+}
+
+func TestParseLevel(t *testing.T) {
+	l, err := ParseLevel("panic")
+	assert.Nil(t, err)
+	assert.Equal(t, PanicLevel, l)
+
+	l, err = ParseLevel("PANIC")
+	assert.Nil(t, err)
+	assert.Equal(t, PanicLevel, l)
+
+	l, err = ParseLevel("fatal")
+	assert.Nil(t, err)
+	assert.Equal(t, FatalLevel, l)
+
+	l, err = ParseLevel("FATAL")
+	assert.Nil(t, err)
+	assert.Equal(t, FatalLevel, l)
+
+	l, err = ParseLevel("error")
+	assert.Nil(t, err)
+	assert.Equal(t, ErrorLevel, l)
+
+	l, err = ParseLevel("ERROR")
+	assert.Nil(t, err)
+	assert.Equal(t, ErrorLevel, l)
+
+	l, err = ParseLevel("warn")
+	assert.Nil(t, err)
+	assert.Equal(t, WarnLevel, l)
+
+	l, err = ParseLevel("WARN")
+	assert.Nil(t, err)
+	assert.Equal(t, WarnLevel, l)
+
+	l, err = ParseLevel("warning")
+	assert.Nil(t, err)
+	assert.Equal(t, WarnLevel, l)
+
+	l, err = ParseLevel("WARNING")
+	assert.Nil(t, err)
+	assert.Equal(t, WarnLevel, l)
+
+	l, err = ParseLevel("info")
+	assert.Nil(t, err)
+	assert.Equal(t, InfoLevel, l)
+
+	l, err = ParseLevel("INFO")
+	assert.Nil(t, err)
+	assert.Equal(t, InfoLevel, l)
+
+	l, err = ParseLevel("debug")
+	assert.Nil(t, err)
+	assert.Equal(t, DebugLevel, l)
+
+	l, err = ParseLevel("DEBUG")
+	assert.Nil(t, err)
+	assert.Equal(t, DebugLevel, l)
+
+	l, err = ParseLevel("invalid")
+	assert.Equal(t, "not a valid logrus Level: \"invalid\"", err.Error())
+}
+
+func TestGetSetLevelRace(t *testing.T) {
+	wg := sync.WaitGroup{}
+	for i := 0; i < 100; i++ {
+		wg.Add(1)
+		go func(i int) {
+			defer wg.Done()
+			if i%2 == 0 {
+				SetLevel(InfoLevel)
+			} else {
+				GetLevel()
+			}
+		}(i)
+
+	}
+	wg.Wait()
+}
+
+func TestLoggingRace(t *testing.T) {
+	logger := New()
+
+	var wg sync.WaitGroup
+	wg.Add(100)
+
+	for i := 0; i < 100; i++ {
+		go func() {
+			logger.Info("info")
+			wg.Done()
+		}()
+	}
+	wg.Wait()
+}
+
+// Compile test
+func TestLogrusInterface(t *testing.T) {
+	var buffer bytes.Buffer
+	fn := func(l FieldLogger) {
+		b := l.WithField("key", "value")
+		b.Debug("Test")
+	}
+	// test logger
+	logger := New()
+	logger.Out = &buffer
+	fn(logger)
+
+	// test Entry
+	e := logger.WithField("another", "value")
+	fn(e)
+}
+
+// Implements io.Writer using channels for synchronization, so we can wait on
+// the Entry.Writer goroutine to write in a non-racey way. This does assume that
+// there is a single call to Logger.Out for each message.
+type channelWriter chan []byte
+
+func (cw channelWriter) Write(p []byte) (int, error) {
+	cw <- p
+	return len(p), nil
+}
+
+func TestEntryWriter(t *testing.T) {
+	cw := channelWriter(make(chan []byte, 1))
+	log := New()
+	log.Out = cw
+	log.Formatter = new(JSONFormatter)
+	log.WithField("foo", "bar").WriterLevel(WarnLevel).Write([]byte("hello\n"))
+
+	bs := <-cw
+	var fields Fields
+	err := json.Unmarshal(bs, &fields)
+	assert.Nil(t, err)
+	assert.Equal(t, fields["foo"], "bar")
+	assert.Equal(t, fields["level"], "warning")
+}

vendor/src/github.com/sirupsen/logrus/terminal_bsd.go

+// +build darwin freebsd openbsd netbsd dragonfly
+// +build !appengine
+
+package logrus
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TIOCGETA
+
+type Termios unix.Termios

vendor/src/github.com/sirupsen/logrus/terminal_linux.go

+// Based on ssh/terminal:
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !appengine
+
+package logrus
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+
+type Termios unix.Termios

vendor/src/github.com/sirupsen/logrus/text_formatter.go

+package logrus
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+const (
+	nocolor = 0
+	red     = 31
+	green   = 32
+	yellow  = 33
+	blue    = 36
+	gray    = 37
+)
+
+var (
+	baseTimestamp time.Time
+)
+
+func init() {
+	baseTimestamp = time.Now()
+}
+
+// TextFormatter formats logs into text
+type TextFormatter struct {
+	// Set to true to bypass checking for a TTY before outputting colors.
+	ForceColors bool
+
+	// Force disabling colors.
+	DisableColors bool
+
+	// Disable timestamp logging. useful when output is redirected to logging
+	// system that already adds timestamps.
+	DisableTimestamp bool
+
+	// Enable logging the full timestamp when a TTY is attached instead of just
+	// the time passed since beginning of execution.
+	FullTimestamp bool
+
+	// TimestampFormat to use for display when a full timestamp is printed
+	TimestampFormat string
+
+	// The fields are sorted by default for a consistent output. For applications
+	// that log extremely frequently and don't use the JSON formatter this may not
+	// be desired.
+	DisableSorting bool
+
+	// QuoteEmptyFields will wrap empty fields in quotes if true
+	QuoteEmptyFields bool
+
+	// Whether the logger's out is to a terminal
+	isTerminal bool
+
+	sync.Once
+}
+
+func (f *TextFormatter) init(entry *Entry) {
+	if entry.Logger != nil {
+		f.isTerminal = f.checkIfTerminal(entry.Logger.Out)
+	}
+}
+
+func (f *TextFormatter) checkIfTerminal(w io.Writer) bool {
+	switch v := w.(type) {
+	case *os.File:
+		return terminal.IsTerminal(int(v.Fd()))
+	default:
+		return false
+	}
+}
+
+// Format renders a single log entry
+func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
+	var b *bytes.Buffer
+	keys := make([]string, 0, len(entry.Data))
+	for k := range entry.Data {
+		keys = append(keys, k)
+	}
+
+	if !f.DisableSorting {
+		sort.Strings(keys)
+	}
+	if entry.Buffer != nil {
+		b = entry.Buffer
+	} else {
+		b = &bytes.Buffer{}
+	}
+
+	prefixFieldClashes(entry.Data)
+
+	f.Do(func() { f.init(entry) })
+
+	isColored := (f.ForceColors || f.isTerminal) && !f.DisableColors
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = defaultTimestampFormat
+	}
+	if isColored {
+		f.printColored(b, entry, keys, timestampFormat)
+	} else {
+		if !f.DisableTimestamp {
+			f.appendKeyValue(b, "time", entry.Time.Format(timestampFormat))
+		}
+		f.appendKeyValue(b, "level", entry.Level.String())
+		if entry.Message != "" {
+			f.appendKeyValue(b, "msg", entry.Message)
+		}
+		for _, key := range keys {
+			f.appendKeyValue(b, key, entry.Data[key])
+		}
+	}
+
+	b.WriteByte('\n')
+	return b.Bytes(), nil
+}
+
+func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []string, timestampFormat string) {
+	var levelColor int
+	switch entry.Level {
+	case DebugLevel:
+		levelColor = gray
+	case WarnLevel:
+		levelColor = yellow
+	case ErrorLevel, FatalLevel, PanicLevel:
+		levelColor = red
+	default:
+		levelColor = blue
+	}
+
+	levelText := strings.ToUpper(entry.Level.String())[0:4]
+
+	if f.DisableTimestamp {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m %-44s ", levelColor, levelText, entry.Message)
+	} else if !f.FullTimestamp {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%04d] %-44s ", levelColor, levelText, int(entry.Time.Sub(baseTimestamp)/time.Second), entry.Message)
+	} else {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s] %-44s ", levelColor, levelText, entry.Time.Format(timestampFormat), entry.Message)
+	}
+	for _, k := range keys {
+		v := entry.Data[k]
+		fmt.Fprintf(b, " \x1b[%dm%s\x1b[0m=", levelColor, k)
+		f.appendValue(b, v)
+	}
+}
+
+func (f *TextFormatter) needsQuoting(text string) bool {
+	if f.QuoteEmptyFields && len(text) == 0 {
+		return true
+	}
+	for _, ch := range text {
+		if !((ch >= 'a' && ch <= 'z') ||
+			(ch >= 'A' && ch <= 'Z') ||
+			(ch >= '0' && ch <= '9') ||
+			ch == '-' || ch == '.' || ch == '_' || ch == '/' || ch == '@' || ch == '^' || ch == '+') {
+			return true
+		}
+	}
+	return false
+}
+
+func (f *TextFormatter) appendKeyValue(b *bytes.Buffer, key string, value interface{}) {
+	if b.Len() > 0 {
+		b.WriteByte(' ')
+	}
+	b.WriteString(key)
+	b.WriteByte('=')
+	f.appendValue(b, value)
+}
+
+func (f *TextFormatter) appendValue(b *bytes.Buffer, value interface{}) {
+	stringVal, ok := value.(string)
+	if !ok {
+		stringVal = fmt.Sprint(value)
+	}
+
+	if !f.needsQuoting(stringVal) {
+		b.WriteString(stringVal)
+	} else {
+		b.WriteString(fmt.Sprintf("%q", stringVal))
+	}
+}

vendor/src/github.com/sirupsen/logrus/text_formatter_test.go

+package logrus
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestFormatting(t *testing.T) {
+	tf := &TextFormatter{DisableColors: true}
+
+	testCases := []struct {
+		value    string
+		expected string
+	}{
+		{`foo`, "time=\"0001-01-01T00:00:00Z\" level=panic test=foo\n"},
+	}
+
+	for _, tc := range testCases {
+		b, _ := tf.Format(WithField("test", tc.value))
+
+		if string(b) != tc.expected {
+			t.Errorf("formatting expected for %q (result was %q instead of %q)", tc.value, string(b), tc.expected)
+		}
+	}
+}
+
+func TestQuoting(t *testing.T) {
+	tf := &TextFormatter{DisableColors: true}
+
+	checkQuoting := func(q bool, value interface{}) {
+		b, _ := tf.Format(WithField("test", value))
+		idx := bytes.Index(b, ([]byte)("test="))
+		cont := bytes.Contains(b[idx+5:], []byte("\""))
+		if cont != q {
+			if q {
+				t.Errorf("quoting expected for: %#v", value)
+			} else {
+				t.Errorf("quoting not expected for: %#v", value)
+			}
+		}
+	}
+
+	checkQuoting(false, "")
+	checkQuoting(false, "abcd")
+	checkQuoting(false, "v1.0")
+	checkQuoting(false, "1234567890")
+	checkQuoting(false, "/foobar")
+	checkQuoting(false, "foo_bar")
+	checkQuoting(false, "foo@bar")
+	checkQuoting(false, "foobar^")
+	checkQuoting(false, "+/-_^@f.oobar")
+	checkQuoting(true, "foobar$")
+	checkQuoting(true, "&foobar")
+	checkQuoting(true, "x y")
+	checkQuoting(true, "x,y")
+	checkQuoting(false, errors.New("invalid"))
+	checkQuoting(true, errors.New("invalid argument"))
+
+	// Test for quoting empty fields.
+	tf.QuoteEmptyFields = true
+	checkQuoting(true, "")
+	checkQuoting(false, "abcd")
+	checkQuoting(true, errors.New("invalid argument"))
+}
+
+func TestEscaping(t *testing.T) {
+	tf := &TextFormatter{DisableColors: true}
+
+	testCases := []struct {
+		value    string
+		expected string
+	}{
+		{`ba"r`, `ba\"r`},
+		{`ba'r`, `ba'r`},
+	}
+
+	for _, tc := range testCases {
+		b, _ := tf.Format(WithField("test", tc.value))
+		if !bytes.Contains(b, []byte(tc.expected)) {
+			t.Errorf("escaping expected for %q (result was %q instead of %q)", tc.value, string(b), tc.expected)
+		}
+	}
+}
+
+func TestEscaping_Interface(t *testing.T) {
+	tf := &TextFormatter{DisableColors: true}
+
+	ts := time.Now()
+
+	testCases := []struct {
+		value    interface{}
+		expected string
+	}{
+		{ts, fmt.Sprintf("\"%s\"", ts.String())},
+		{errors.New("error: something went wrong"), "\"error: something went wrong\""},
+	}
+
+	for _, tc := range testCases {
+		b, _ := tf.Format(WithField("test", tc.value))
+		if !bytes.Contains(b, []byte(tc.expected)) {
+			t.Errorf("escaping expected for %q (result was %q instead of %q)", tc.value, string(b), tc.expected)
+		}
+	}
+}
+
+func TestTimestampFormat(t *testing.T) {
+	checkTimeStr := func(format string) {
+		customFormatter := &TextFormatter{DisableColors: true, TimestampFormat: format}
+		customStr, _ := customFormatter.Format(WithField("test", "test"))
+		timeStart := bytes.Index(customStr, ([]byte)("time="))
+		timeEnd := bytes.Index(customStr, ([]byte)("level="))
+		timeStr := customStr[timeStart+5+len("\"") : timeEnd-1-len("\"")]
+		if format == "" {
+			format = time.RFC3339
+		}
+		_, e := time.Parse(format, (string)(timeStr))
+		if e != nil {
+			t.Errorf("time string \"%s\" did not match provided time format \"%s\": %s", timeStr, format, e)
+		}
+	}
+
+	checkTimeStr("2006-01-02T15:04:05.000000000Z07:00")
+	checkTimeStr("Mon Jan _2 15:04:05 2006")
+	checkTimeStr("")
+}
+
+func TestDisableTimestampWithColoredOutput(t *testing.T) {
+	tf := &TextFormatter{DisableTimestamp: true, ForceColors: true}
+
+	b, _ := tf.Format(WithField("test", "test"))
+	if strings.Contains(string(b), "[0000]") {
+		t.Error("timestamp not expected when DisableTimestamp is true")
+	}
+}
+
+// TODO add tests for sorting etc., this requires a parser for the text
+// formatter output.

vendor/src/github.com/sirupsen/logrus/writer.go

+package logrus
+
+import (
+	"bufio"
+	"io"
+	"runtime"
+)
+
+func (logger *Logger) Writer() *io.PipeWriter {
+	return logger.WriterLevel(InfoLevel)
+}
+
+func (logger *Logger) WriterLevel(level Level) *io.PipeWriter {
+	return NewEntry(logger).WriterLevel(level)
+}
+
+func (entry *Entry) Writer() *io.PipeWriter {
+	return entry.WriterLevel(InfoLevel)
+}
+
+func (entry *Entry) WriterLevel(level Level) *io.PipeWriter {
+	reader, writer := io.Pipe()
+
+	var printFunc func(args ...interface{})
+
+	switch level {
+	case DebugLevel:
+		printFunc = entry.Debug
+	case InfoLevel:
+		printFunc = entry.Info
+	case WarnLevel:
+		printFunc = entry.Warn
+	case ErrorLevel:
+		printFunc = entry.Error
+	case FatalLevel:
+		printFunc = entry.Fatal
+	case PanicLevel:
+		printFunc = entry.Panic
+	default:
+		printFunc = entry.Print
+	}
+
+	go entry.writerScanner(reader, printFunc)
+	runtime.SetFinalizer(writer, writerFinalizer)
+
+	return writer
+}
+
+func (entry *Entry) writerScanner(reader *io.PipeReader, printFunc func(args ...interface{})) {
+	scanner := bufio.NewScanner(reader)
+	for scanner.Scan() {
+		printFunc(scanner.Text())
+	}
+	if err := scanner.Err(); err != nil {
+		entry.Errorf("Error while reading from Writer: %s", err)
+	}
+	reader.Close()
+}
+
+func writerFinalizer(writer *io.PipeWriter) {
+	writer.Close()
+}