go-httpclient

Advanced HTTP client for golang.

Features

• Chainable API
• Direct file upload
• Timeout
• HTTP Proxy
• Cookie
• GZIP
• Redirect Policy

Installation

go get github.com/ddliu/go-httpclient

Quick Start

package main

import (
    "github.com/ddliu/go-httpclient"
)

func main() {
    httpclient.Defaults(httpclient.Map {
        httpclient.OPT_USERAGENT: "my awsome httpclient",
        "Accept-Language": "en-us",
    })

    res, err := httpclient.Get("http://google.com/search", map[string]string{
        "q": "news",
    })

    println(res.StatusCode, err)
}

Usage

Setup

Use httpclient.Defaults to setup default behaviors of the HTTP client.

httpclient.Defaults(httpclient.Map {
    httpclient.OPT_USERAGENT: "my awsome httpclient",
    "Accept-Language": "en-us",
})

The OPT_XXX options define basic behaviours of this client, other values are default request headers of this request. They are shared between different HTTP requests.

GET/POST

In most cases you just need the Get and Post method after initializing:

func (this *HttpClient) Get(url string, params map[string]string) (*httpclient.Response, error)

func (this *HttpClient) Post(url string, params map[string]string) (*httpclient.Response, error)

    res, err := httpclient.Get("http://google.com/search", map[string]string{
        "q": "news",
    })

    fmt.Println(res.StatusCode, err)

    // post file
    res, err := httpclient.Post("http://dropbox.com/upload", map[string]string {
        "@file": "/tmp/hello.pdf",
    })

    fmt.Println(res, err)

Customize Request

Before you start a new HTTP request with Get or Post method, you can specify temporary options, headers or cookies for current request.

httpclient.
    WithHeader("User-Agent", "Super Robot").
    WithHeader("custom-header", "value").
    WithHeaders(map[string]string {
        "another-header": "another-value",
        "and-another-header": "another-value",
    }).
    WithOption(httpclent.OPT_TIMEOUT, 60).
    WithCookie(&http.Cookie{
        Name: "uid",
        Value: "123",
    }).
    Get("http://github.com", nil)

Response

The httpclient.Response is a thin wrap of http.Response.

// traditional
res, err := httpclient.Get("http://google.com", nil)
bodyBytes, err := ioutil.ReadAll(res.Body)
res.Body.Close()

// ToString
res, err = httpclient.Get("http://google.com", nil)
bodyString,err := res.ToString()

// ReadAll
res, err = httpclient.Get("http://google.com", nil)
bodyBytes := res.ReadAll()

Handle Cookies

url := "http://github.com"
httpclient.
    WithCookie(&http.Cookie{
        Name: "uid",
        Value: "123",
    }).
    Get(url, nil)

for _, cookie := range httpclient.Cookies() {
    fmt.Println(cookie.Name, cookie.Value)
}

for k, v := range httpclient.CookieValues() {
    fmt.Println(k, v)
}

fmt.Println(httpclient.CookieValue("uid"))

Concurrent Safe

If you want to start many requests concurrently, remember to call the Begin method when you begin:

go func() {
    httpclient.
        Begin().
        WithHeader("Req-A", "a").
        Get("http://google.com")
}()
go func() {
    httpclient.
        Begin().
        WithHeader("Req-B", "b").
        Get("http://google.com")
}()

Error Checking

You can use httpclient.IsTimeoutError to check for timeout error:

res, err := httpclient.Get("http://google.com", nil)
if httpclient.IsTimeoutError(err) {
    // do something
}

Full Example

See examples/main.go

Options

Available options as below:

• OPT_FOLLOWLOCATION: TRUE to follow any "Location: " header that the server sends as part of the HTTP header. Default to true.
• OPT_CONNECTTIMEOUT: The number of seconds to wait while trying to connect. Use 0 to wait indefinitely.
• OPT_CONNECTTIMEOUT_MS: The number of milliseconds to wait while trying to connect. Use 0 to wait indefinitely.
• OPT_MAXREDIRS: The maximum amount of HTTP redirections to follow. Use this option alongside OPT_FOLLOWLOCATION.
• OPT_PROXYTYPE: Specify the proxy type. Valid options are PROXY_HTTP, PROXY_SOCKS4, PROXY_SOCKS5, PROXY_SOCKS4A. Only PROXY_HTTP is supported currently.
• OPT_TIMEOUT: The maximum number of seconds to allow httpclient functions to execute.
• OPT_TIMEOUT_MS: The maximum number of milliseconds to allow httpclient functions to execute.
• OPT_COOKIEJAR: Set to true to enable the default cookiejar, or you can set to a http.CookieJar instance to use a customized jar. Default to true.
• OPT_INTERFACE: TODO
• OPT_PROXY: Proxy host and port(127.0.0.1:1080).
• OPT_REFERER: The Referer header of the request.
• OPT_USERAGENT: The User-Agent header of the request. Default to "go-httpclient v{{VERSION}}".
• OPT_REDIRECT_POLICY: Function to check redirect.
• OPT_PROXY_FUNC: Function to specify proxy.
• OPT_DEBUG: Print request info.

Seperate Clients

By using the httpclient.Get, httpclient.Post methods etc, you are using a default shared HTTP client.

If you need more than one clients in a single programe. Just create and use them seperately.

c1 := httpclient.NewHttpClient().Defaults(httpclient.Map {
    httpclient.OPT_USERAGENT: "browser1",
})

c1.Get("http://google.com/", nil)

c2 := httpclient.NewHttpClient().Defaults(httpclient.Map {
    httpclient.OPT_USERAGENT: "browser2",
})

c2.Get("http://google.com/", nil)

TODO

• Support all HTTP methods directly
• Direct JSON support?
• Socks proxy support
• Improve API design