zapappender

Composable appender for uber-go/zap enabling:

• Async logging
• Fallback
• Message Enveloping (like syslog formatting)

This project was created to allow logging to syslog over TCP.

Quick start

Firstly, compose the appender chain:

primaryOut := zapappender.NewWriter(zapcore.Lock(someTcpWriter))
consoleWriter := zapappender.NewWriter(zapcore.Lock(os.Stdout))
secondaryOut := zapappender.NewEnvelopingPreSuffix(consoleWriter, "FALLBACK: ", "")
fallback := zapappender.NewFallback(primaryOut, secondaryOut)
async, _ := zapappender.NewAsync(fallback,
    zapappender.AsyncOnQueueNearlyFullForwardTo(secondaryOut),
    zapappender.AsyncMaxQueueLength(10),
    zapappender.AsyncQueueMinFreePercent(0.2),
    zapappender.AsyncQueueMonitorPeriod(time.Millisecond),
)
appenderChain := async

Secondly, use that chain to create a zapcore.Core and finally to construct a zap.Logger.

encoder := zapcore.NewConsoleEncoder(encoderConfig)
core := zapappender.NewAppenderCore(encoder, appenderChain, zapcore.DebugLevel)
logger := zap.New(core)

logger.Info("this logs async")

See example_test.go for more details.