gzap - Graylog Integrated Zap Logger

Gzap provide fast structured leveled logging using zap, and a TCP/UDP Graylog logsink (TLS supported). Both zap and Graylog librarys are versioned locked within the applications so no other external dependencies required.

Getting Stated

To use gzap, first import it:

import "gopkg.in/dailymuse/gzap.v1"

The Graylog logsink is only enabled for Production and Staging environments. So you'll need to set a GRAYLOG_ENV environment variable with either of the following correlating states.

GRAYLOG_ENV	Environment	Graylog enabled?
0	Test (no-op logger)	❌
1	Dev	❌
2	Staging	✅
3	Production	✅

Environment Variables

To properly use gzap you'll need to set your configurations via Environment variables. The following are configurable Envs:

Env Name	Description
GRAYLOG_ENV	A number 0 - 3 describing the Graylog loggin environment you wish to use (Refrence table above)
GRAYLOG_HOST	Hostname that your graylog is currently listening on example.graylog.com
ENABLE_DATADOG_JSON_FORMATTER	set to "true" to enable json formatted logs.

Internal API

The logger that is publicly exposed is the zap Logger. You can reference what log levels are available for use here). Below are a few examples:

func (log *Logger) DPanic(msg string, fields ...zapcore.Field)
func (log *Logger) Debug(msg string, fields ...zapcore.Field)
func (log *Logger) Error(msg string, fields ...zapcore.Field)
func (log *Logger) Fatal(msg string, fields ...zapcore.Field)
func (log *Logger) Info(msg string, fields ...zapcore.Field)
func (log *Logger) Panic(msg string, fields ...zapcore.Field)
func (log *Logger) Warn(msg string, fields ...zapcore.Field)

All zap fields needed for logging are also exposed by gzap.

gzap.Logger.Error("this is an example Error log",
        gzap.String("variable", "some-variable-here"),
)

For any other information please take a look at the gzap Godoc.

Example Usage

package main

import (
    "time"

    "gopkg.in/dailymuse/gzap.v1"
)

func main() {
    // Instantiate a global logger.
    if err := gzap.InitLogger(); err != nil {
        panic(err)
    }

    // Example Info log.
    gzap.Logger.Info("this is an example Info log",
        gzap.String("process name", "some-fake-name"),
        gzap.Int64("expectedDocs", int64(255)),
        gzap.Int64("docsUploaded", int64(100)),
    )

    // Example Error log.
    gzap.Logger.Error("this is an example Error log",
        gzap.Error(errors.New("example error")),
        gzap.String("index name", "my-full-index-name"),
        gzap.Float64("time elapsed", float64(1002)),
    )

    // Example Debug log.
    gzap.Logger.Debug("this is an example Debug log",
        gzap.String("variable", "some-variable-here"),
    )
}

Important info

Contributing

In order to contribute you'll need to have a valid go environment setup.

If you need to install go, see installation instructions here.

Tests Logs are a no-op

Tests that run application code containing logs will not print those logs by default. The Test logger is a no-op to reduce noise during testing.