ltsvlog

ltsvlog is a minimalist LTSV; Labeled Tab-separated Values logging library in Go. See https://godoc.org/github.com/hnakamur/ltsvlog for the API document.

Warning

• This project is open source, but closed development, no support, no pull request welcome. If you are unsatisfied, feel free to fork it, pick another library, or roll your own.
• I understand this may be a "Don't do that" style in the Go logging and error handling best practices.
• I don't promise the future compatibility. Also this library may not work in the future versions of Go, and a migration path may not be provided, leading to the dead end, users of this library will have to rewrite all of your code. You are on your own with no help.

An example code and output

An example code:

package main

import (
	"github.com/hnakamur/errstack"
	ltsvlog "github.com/hnakamur/ltsvlog/v3"
)

func main() {
	if ltsvlog.Logger.DebugEnabled() {
		ltsvlog.Logger.Debug().String("msg", "This is a debug message").
			String("str", "foo").Int("int", 234).Log()
	}

	ltsvlog.Logger.Info().Fmt("float1", "%3.2f", 3.14).Log()

	if err := outer(); err != nil {
		ltsvlog.Logger.Err(err)
	}
}

func outer() error {
	if err := inner(); err != nil {
		return errstack.WithLV(errstack.Errorf("add some message here: %s", err)).Int64("userID", 1)
	}
	return nil
}

func inner() error {
	return errstack.WithLV(errstack.New("some error")).String("reqID", "req1")
}

An example output:

time:2019-10-21T21:46:53.777197Z	level:Debug	msg:This is a debug message	str:foo	int:234
time:2019-10-21T21:46:53.777232Z	level:Info	float1:3.14
time:2019-10-21T21:46:53.777272Z	level:Error	err:add some message here: some error	userID:1	stack:main.inner@/home/hnakamur/go/src/github.com/hnakamur/ltsvlog/example/main.go:31 main.outer@/home/hnakamur/go/src/github.com/hnakamur/ltsvlog/example/main.go:22 main.main@/home/hnakamur/go/src/github.com/hnakamur/ltsvlog/example/main.go:16 runtime.main@/usr/local/go/src/runtime/proc.go:203

Since these log lines are long, please scroll horizontally to the right to see all the output.

Goals and non-goals

Goals

• structured logging in LTSV format.
• fast operation and minimum count of memory allocations for Debug and Info.
• log call stack frames with optional labeled values as long as the error message.

Non-Goals

• compatiblity with the Go logging best practices.
• fast operation and minimum count of memory allocations for Err.
• flexibility and features.

Benchmark result

hnakamur/go-log-benchmarks

License

MIT