# req
[![GoDoc](https://godoc.org/github.com/imroc/req?status.svg)](https://godoc.org/github.com/imroc/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
========
[中文](doc/README_cn.md)


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

// use req package to initiate request.
req.Get(url)
```
You can use `req.New()` to create lots of `*Req` as client with independent configuration

Examples
=======
[Basic](#Basic)  
[Set Header](#Set-Header)  
[Set Param](#Set-Param)  
[Set Body](#Set-Body)  
[Debug](#Debug)  
[Output Format](#Format)  
[ToJSON & ToXML](#ToJSON-ToXML)  
[Get *http.Response](#Response)  
[Upload](#Upload)  
[Download](#Download)  
[Cookie](#Cookie)  
[Set Timeout](#Set-Timeout)  
[Set Proxy](#Set-Proxy)  
[Customize Client](#Customize-Client)  

## <a name="Basic">Basic</a>
``` go
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) 
```

## <a name="Set-Header">Set Header</a>
Use `req.Header` (it is actually a `map[string]string`)
``` go
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`
``` go
header := make(http.Header)
header.Set("Accept", "application/json")
req.Get("https://www.baidu.com", header)
```

## <a name="Set-Param">Set Param</a>
Use `req.Param` (it is actually a `map[string]interface{}`)
``` go
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]interface{}`)
``` go
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
*/
```

## <a name="Set-Body">Set Body</a>
Put `string`, `[]byte` and `io.Reader` as body directly.
``` go
req.Post(url, "id=roc&cmd=query")
```
Put object as xml or json body (add `Content-Type` header automatically)
``` go
req.Post(url, req.BodyJSON(&foo))
req.Post(url, req.BodyXML(&bar))
```

## <a name="Debug">Debug</a>
Set global variable `req.Debug` to true, it will print detail infomation for every request.
``` go
req.Debug = true
req.Post("http://localhost/test" "hi")
```
![post](doc/post.png)

## <a name="Format">Output Format</a>
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
``` go
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)
``` go
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.
``` go
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
)
```
``` go
req.SetFlags(req.LreqHead | req.LreqBody | req.LrespHead)
```

### Monitoring time consuming
``` go
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)
}
```

## <a name="ToJSON-ToXML">ToJSON & ToXML</a>
``` go
r, _ := req.Get(url)
r.ToJSON(&foo)
r, _ = req.Post(url, req.BodyXML(&bar))
r.ToXML(&baz)
```

## <a name="Response">Get *http.Response</a>
```go
// func (r *Req) Response() *http.Response
r, _ := req.Get(url)
resp := r.Response()
fmt.Println(resp.StatusCode)
```

## <a name="Upload">Upload</a>
Use `req.File` to match files
``` go
req.Post(url, req.File("imroc.png"), req.File("/Users/roc/Pictures/*.png"))
```
Use `req.FileUpload` to fully control
``` go
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
})
```
Use `req.UploadProgress` to listen upload progress
```go
progress := func(current, total int64) {
	fmt.Println(float32(current)/float32(total)*100, "%")
}
req.Post(url, req.File("/Users/roc/Pictures/*.png"), req.UploadProgress(progress))
fmt.Println("upload complete")
```

## <a name="Download">Download</a>
``` go
r, _ := req.Get(url)
r.ToFile("imroc.png")
```
Use `req.DownloadProgress` to listen download progress
```go
progress := func(current, total int64) {
	fmt.Println(float32(current)/float32(total)*100, "%")
}
r, _ := req.Get(url, req.DownloadProgress(progress))
r.ToFile("hello.mp4")
fmt.Println("download complete")
```

## <a name="Cookie">Cookie</a>
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 :
``` go
req.EnableCookie(false)
```
and you can set cookie in request just using `*http.Cookie`
``` go
cookie := new(http.Cookie)
// ......
req.Get(url, cookie)
```

## <a name="Set-Timeout">Set Timeout</a>
``` go
req.SetTimeout(50 * time.Second)
```

## <a name="Set-Proxy">Set Proxy</a>
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`
``` go
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)
``` go
req.SetProxyUrl("http://my.proxy.com:23456")
```

## <a name="Customize-Client">Customize Client</a>
Use `SetClient` to change the default underlying `*http.Client`
``` go
req.SetClient(client)
```
Specify independent http client for some requests
``` go
client := &http.Client{Timeout: 30 * time.Second}
req.Get(url, client)
```
Change some properties of default client you want
``` go
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}
```