【Golang 接口自动化01】使用标准库net/http发送Get请求

发送Get请求

使用Golang发送get请求很容易，我们还是使用http://httpbin.org作为服务端来进行演示。

package main

import (
    "bytes"
    "fmt"
    "log"
    "net/http"
    "net/url"
    "reflect"
)

func main() {
    resp, err := http.Get("http://httpbin.org/get?name=Detector")

    if err != nil {
        log.Println(err)
        return
    }

    defer resp.Body.Close()

    headers := resp.Header
    // headers 打印报文头部信息
    for k, v := range headers {
        fmt.Printf("%v, %v\n", k, v) // %v 打印interfac{}的值
    }

    // 打印响应信息内容
    fmt.Printf("响应状态：%s,响应码： %d\n", resp.Status, resp.StatusCode)
    fmt.Printf("协议：%s\n", resp.Proto)
    fmt.Printf("响应内容长度： %d\n", resp.ContentLength)
    fmt.Printf("编码格式：%v\n", resp.TransferEncoding) // 未指定时为空
    fmt.Printf("是否压缩：%t\n", resp.Uncompressed)
    fmt.Println(reflect.TypeOf(resp.Body)) // *http.gzipReader
    fmt.Println(resp.Close)

    buf := bytes.NewBuffer(make([]byte, 0, 512))
    length, _ := buf.ReadFrom(resp.Body)
    fmt.Println(len(buf.Bytes()))
    fmt.Println(length)
    fmt.Println(string(buf.Bytes()))
}

响应信息

λ go run goHttp.go
Access-Control-Allow-Credentials, [true]
Via, [1.1 vegur]
Connection, [keep-alive]
Server, [gunicorn/19.9.0]
Date, [Tue, 18 Sep 2018 02:25:16 GMT]
Content-Type, [application/json]
Content-Length, [271]
Access-Control-Allow-Origin, [*]
"响应状态"：200 OK,响应码： 200
"协议"：HTTP/1.1
"响应内容长度"： 271
"编码格式"：[]
"是否压缩"：false
*http.bodyEOFSignal
false
271
271
{
  "args": {
    "name": "Detector"
  },
  "headers": {
    "Accept-Encoding": "gzip",
    "Connection": "close",
    "Host": "httpbin.org",
    "User-Agent": "Go-http-client/1.1"
  },
  "origin": "14.152.49.250",
  "url": "http://httpbin.org/get?name=Detector"
}

更多的响应内容我们查看安装路径的net包中Response struct 的信息，里面有详细的注释，参考路径：C:\Go\src\net\http\response.go:

拓展

用过Python的同学都知道，Python的requests发送get请求时是可以直接传递字典的（dict/map）的，比如：

#! /usr/bin/python
import requests

a = {"name": "bingo", "age": "18", "location": "shenzhen"}

name = {"name": "Detector"}
resp = requests.get("http://httpbin.org/get", params=a)
print(resp.text)

响应信息：

{
  "args": {
    "age": "18", 
    "location": "shenzhen", 
    "name": "bingo"
  }, 
  "headers": {
    "Accept": "*/*", 
    "Accept-Encoding": "gzip, deflate", 
    "Connection": "close", 
    "Host": "httpbin.org", 
    "User-Agent": "python-requests/2.18.4"
  }, 
  "origin": "14.152.49.250", 
  "url": "http://httpbin.org/get?name=bingo&age=18&location=shenzhen"
}

那么在golang中有没有想过的方法呢，答案是有的，但是只有一个半成品。

在C:\Go\src\net\url\url.go中我们可以看到一个结构体type Values map[string][]string,他有一个Encode()方法可以把key:value键值对转化为key=value&key=value的形式：

package main

import (
    "fmt"
    "io/ioutil"
    "log"
    "net/http"
    "net/url"
)

func main() {
    name := url.Values{"name": {"bingo"}, "age": {"18"}, "local": {"shenzhen"}}
    param := name.Encode()
    url := fmt.Sprintf("http://httpbin.org/get?%s", param)
    fmt.Println(url)

    resp, err := http.Get(url)

    if err != nil {
        log.Println(err)
        return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    fmt.Println(string(body))
}

输出：

http://httpbin.org/get?age=18&local=shenzhen&name=bingo
{
  "args": {
    "age": "18", 
    "local": "shenzhen", 
    "name": "bingo"
  }, 
  "headers": {
    "Accept-Encoding": "gzip", 
    "Connection": "close", 
    "Host": "httpbin.org", 
    "User-Agent": "Go-http-client/1.1"
  }, 
  "origin": "103.84.19.17", 
  "url": "http://httpbin.org/get?age=18&local=shenzhen&name=bingo"
}

考虑到篇幅，我们把发送Get、Post单独出来。我们在下一篇一起学习怎么发送Post请求。