darrylwest/cassava-logger

a small multi-target logger with middleware written in go

Cassava Logger

A log4j-like logger with levels, multiple handlers and middleware implementation. This implementation is optimized for rolling files suitable for services, middleware, etc.

This package is based on siddontang's go-log project.

Install

go get github.com/darrylwest/cassava-logger/logger

Simple Use

There are instance and type methods (Trace, Debug, Info, Warn, Error, Fatal) that support simple stream logging to the console. An example of type use would be:

logger.Info("this is a test...") 
// -> hh:mm:ss.SSS INFO filename:line this is a test...

logger.Warn("this is a warning") 
// -> hh:mm:ss.SSS WARN filename:line this is a warning

There are the same methods implemented on an instance, for example:

import "github.com/darrylwest/cassava-logger/logger"

// create a logger with specified handler
handler,_ := logger.NewStreamHandler(os.Stdout)
log := logger.NewLogger( handler )

log.Debug("debug level log statement") // will be suppressed
log.Info("info level log statement")
log.Warn("warn level log statement")
log.Error("errorlevel log statement")

log.SetLevel( logger.DebugLevel )
log.Debug("this debug message shows up...")

Rolling File Logger

There are multiple rolling file handlers to support rolling by size or time. Times include second, minute, hour and day. The rotating day handler is used in the logger middleware project.

You will find an example similar to this in "examples". The log's filename is changed to "day-logger.YYYY-MM-DD.log" and rotates daily.

handler,_ := logger.NewRotatingDayHandler( "./day-logger" )
log := logger.NewLogger( handler )

log.Debug("my debug message (suppressed)")
log.Info("my message")
log.Warn("my warning")
log.Error("my error")

log.SetLevel( logger.DebugLevel )
log.Debug("this should show")

Middleware

Cassava logger may be used as middleware for negroni http-server like this:

handler,_ := logger.NewRotatingDayHandler( "./web-logger" )
log := logger.NewLogger( handler )

server := negroni.New()

server.Use(logger.NewMiddlewareLogger( log ))
...

All incoming requests log the requesting host, URL/path, agent and the time required to process the request.

Note: if the request URL/path equals "/ping" and the user agent is "heathcheck", the log statement is skipped. This enables load balancers the ability to do health-checks without filling up log files.

To Do

• implement categories to optionally replace file/line in log statements
• create config for reading and re-reading configurations
• complete unit tests for 100% coverage
• add travis tests
• create test folder/package with data fixtures

License

MIT Licensed. See LICENSE file for details. Use as you wish. Fork and help out if you can.

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Version 17.9.5 | darryl.west@raincitysoftware.com