req

A golang http request library for humans

Features

Light weight
Simple
Easy play with JSON and XML
Easy for debug and logging
Easy file uploads and downloads
Easy manage cookie
Easy set up proxy
Easy set timeout
Easy customize http client

Document

Install

go get github.com/imroc/req

Overview

req implements a friendly API over Go's existing net/http library.

Req and Resp are two most important struct, you can think of Req as a client that initiate HTTP requests, Resp as a information container for the request and response. They all provide simple and convenient APIs that allows you to do a lot of things.

func (r *Req) Post(url string, v ...interface{}) (*Resp, error)

In most cases, only url is required, others are optional, like headers, params, files or body etc.

There is a default Req object, all of its' public methods are wrapped by the req package, so you can also think of req package as a Req object

// use Req object to initiate requests.
r := req.New()
r.Get(url)

// use req package to initiate reqeust.
req.Get(url)

You can use req.New() to create lots of *Req as client with independent configuration

Examples

Basic
Set Header
Set Param
Set Body
Debug
Output Format
ToJSON & ToXML
Get *http.Response
Upload
Download
Cookie
Set Timeout
Set Proxy
Customize Client

Basic

header := req.Header{
	"Accept":        "application/json",
	"Authorization": "Basic YWRtaW46YWRtaW4=",
}
param := req.Param{
	"name": "imroc",
	"cmd":  "add",
}
// only url is required, others are optional.
r, err = req.Post("http://foo.bar/api", header, param)
if err != nil {
	log.Fatal(err)
}
r.ToJSON(&foo)       // response => struct/map
log.Printf("%+v", r) // print info (try it, you may surprise)

Set Header

Use req.Header (it is actually a map[string]string)

authHeader := req.Header{
	"Accept":        "application/json",
	"Authorization": "Basic YWRtaW46YWRtaW4=",
}
req.Get("https://www.baidu.com", authHeader, req.Header{"User-Agent": "V1.1"})

use http.Header

header := make(http.Header)
header.Set("Accept", "application/json")
req.Get("https://www.baidu.com", header)

Set Param

Use req.Param (it is actually a map[string]string)

param := req.Param{
	"id":  "imroc",
	"pwd": "roc",
}
req.Get("http://foo.bar/api", param) // http://foo.bar/api?id=imroc&pwd=roc
req.Post(url, param)                  // body => id=imroc&pwd=roc

use req.QueryParam force to append params to the url (it is also actually a map[string]string)

req.Post("http://foo.bar/api", req.Param{"name": "roc", "age": "22"}, req.QueryParam{"access_token": "fedledGF9Hg9ehTU"})
/*
POST /api?access_token=fedledGF9Hg9ehTU HTTP/1.1
Host: foo.bar
User-Agent: Go-http-client/1.1
Content-Length: 15
Content-Type: application/x-www-form-urlencoded;charset=UTF-8
Accept-Encoding: gzip

age=22&name=roc
*/

Set Body

Put string, []byte and io.Reader as body directly.

req.Post(url, "id=roc&cmd=query")

Put object as xml or json body (add Content-Type header automatically)

req.Post(url, req.BodyJSON(&foo))
req.Post(url, req.BodyXML(&bar))

Debug

Set global variable req.Debug to true, it will print detail infomation for every request.

req.Debug = true
req.Post("http://localhost/test" "hi")

Output Format

You can use different kind of output format to log the request and response infomation in your log file in defferent scenarios. For example, use %+v output format in the development phase, it allows you to observe the details. Use %v or %-v output format in production phase, just log the information necessarily.

`%+v` or `%+s`

Output in detail

r, _ := req.Post(url, header, param)
log.Printf("%+v", r) // output the same format as Debug is enabled

`%v` or `%s`

Output in simple way (default format)

r, _ := req.Get(url, param)
log.Printf("%v\n", r) // GET http://foo.bar/api?name=roc&cmd=add {"code":"0","msg":"success"}
log.Prinln(r)         // smae as above

`%-v` or `%-s`

Output in simple way and keep all in one line (request body or response body may have multiple lines, this format will replace "\r" or "\n" with " ", it's useful when doing some search in your log file)

Flag

You can call SetFlags to control the output content, decide which pieces can be output.

const (
	LreqHead  = 1 << iota // output request head (request line and request header)
	LreqBody              // output request body
	LrespHead             // output response head (response line and response header)
	LrespBody             // output response body
	Lcost                 // output time costed by the request
	LstdFlags = LreqHead | LreqBody | LrespHead | LrespBody
)

req.SetFlags(req.LreqHead | req.LreqBody | req.LrespHead)

Monitoring time consuming

req.SetFlags(req.LstdFlags | req.Lcost) // output format add time costed by request
r,_ := req.Get(url)
log.Println(r) // http://foo.bar/api 3.260802ms {"code":0 "msg":"success"}
if r.Cost() > 3 * time.Second { // check cost
	log.Println("WARN: slow request:", r)
}

ToJSON & ToXML

r, _ := req.Get(url)
r.ToJSON(&foo)
r, _ = req.Post(url, req.BodyXML(&bar))
r.ToXML(&baz)

Get *http.Response

// func (r *Req) Response() *http.Response
r, _ := req.Get(url)
resp := r.Response()
fmt.Println(resp.StatusCode)

Upload

Use req.File to match files

req.Post(url, req.File("imroc.png"), req.File("/Users/roc/Pictures/*.png"))

Use req.FileUpload to fully control

file, _ := os.Open("imroc.png")
req.Post(url, req.FileUpload{
	File:      file,
	FieldName: "file",       // FieldName is form field name
	FileName:  "avatar.png", //Filename is the name of the file that you wish to upload. We use this to guess the mimetype as well as pass it onto the server
})

Download

r, _ := req.Get(url)
r.ToFile("imroc.png")

By default, the underlying *http.Client will manage your cookie(send cookie header to server automatically if server has set a cookie for you), you can disable it by calling this function :

req.EnableCookie(false)

and you can set cookie in request just using *http.Cookie

cookie := new(http.Cookie)
// ......
req.Get(url, cookie)

Set Timeout

req.SetTimeout(50 * time.Second)

Set Proxy

By default, req use proxy from system environment if http_proxy or https_proxy is specified, you can set a custom proxy or disable it by set nil

req.SetProxy(func(r *http.Request) (*url.URL, error) {
	if strings.Contains(r.URL.Hostname(), "google") {
		return url.Parse("http://my.vpn.com:23456")
	}
	return nil, nil
})

Set a simple proxy (use fixed proxy url for every request)

req.SetProxyUrl("http://my.proxy.com:23456")

Customize Client

Use SetClient to change the default underlying *http.Client

req.SetClient(client)

Specify independent http client for some requests

client := &http.Client{Timeout: 30 * time.Second}
req.Get(url, client)

Change some properties of default client you want

req.Client().Jar, _ = cookiejar.New(nil)
trans, _ := req.Client().Transport.(*http.Transport)
trans.MaxIdleConns = 20
trans.TLSHandshakeTimeout = 20 * time.Second
trans.DisableKeepAlives = true
trans.TLSClientConfig = &tls.Config{InsecureSkipVerify: true}

yang-f / req

req