httplogger

README

httplogger

Small Go library useful for logging API requests.

It wraps any http.Transport to log its requests and responses, including the duration time.

Usage

See example/example.go

package main

import (
	"log"
	"net/http"
	"os"
	"time"

	"go.mills.io/httplogger"
)

func main() {
	client := http.Client{
		Transport: httplogger.NewLoggedTransport(http.DefaultTransport, newLogger()),
	}

	client.Get("http://google.com")
}

type httpLogger struct {
	log *log.Logger
}

func newLogger() *httpLogger {
	return &httpLogger{
		log: log.New(os.Stderr, "log - ", log.LstdFlags),
	}
}

func (l *httpLogger) LogRequest(req *http.Request) {
	l.log.Printf(
		"Request %s %s",
		req.Method,
		req.URL.String(),
	)
}

func (l *httpLogger) LogResponse(req *http.Request, res *http.Response, err error, duration time.Duration) {
	duration /= time.Millisecond
	if err != nil {
		l.log.Println(err)
	} else {
		l.log.Printf(
			"Response method=%s status=%d durationMs=%d %s",
			req.Method,
			res.StatusCode,
			duration,
			req.URL.String(),
		)
	}
}

Output:

$ go run example/example.go
log - 2014/08/17 02:19:19 Request GET http://google.com
log - 2014/08/17 02:19:19 Response method=GET status=302
durationMs=85 http://google.com
log - 2014/08/17 02:19:19 Request GET
http://www.google.co.uk/?gfe_rd=cr&ei=GwPwU4GtPMKo8we3koKwDg
log - 2014/08/17 02:19:20 Response method=GET status=200
durationMs=138
http://www.google.co.uk/?gfe_rd=cr&ei=GwPwU4GtPMKo8we3koKwDg

LICENSE

httplogger is licensed under the terms of the MIT License.

Previously based off of httplogger by Ernesto JimC)nez (See LICENSE.old)

Documentation

Index

• Variables
• func NewLoggedTransport(rt http.RoundTripper, log HTTPLogger) http.RoundTripper
• type DefaultLogger
  • func (dl DefaultLogger) LogRequest(*http.Request)
  • func (dl DefaultLogger) LogResponse(req *http.Request, res *http.Response, err error, duration time.Duration)
• type HTTPLogger

Variables

var DefaultLoggedTransport = NewLoggedTransport(http.DefaultTransport, DefaultLogger{})

DefaultLoggedTransport wraps http.DefaultTransport to log using DefaultLogger

Functions

func NewLoggedTransport

func NewLoggedTransport(rt http.RoundTripper, log HTTPLogger) http.RoundTripper

NewLoggedTransport takes an http.RoundTripper and returns a new one that logs requests and responses

Types

type DefaultLogger

type DefaultLogger struct {
}

DefaultLogger is an http logger that will use the standard logger in the log package to provide basic information about http responses

func (DefaultLogger) LogRequest

func (dl DefaultLogger) LogRequest(*http.Request)

LogRequest doens't do anything since we'll be logging replies only

func (DefaultLogger) LogResponse

func (dl DefaultLogger) LogResponse(req *http.Request, res *http.Response, err error, duration time.Duration)

LogResponse logs path, host, status code and duration in milliseconds

type HTTPLogger

type HTTPLogger interface {
	LogRequest(*http.Request)
	LogResponse(*http.Request, *http.Response, error, time.Duration)
}

HTTPLogger defines the interface to log http request and responses