Go的HttpClient实现

package main

import (
    "encoding/json"
    "fmt"
    "io/ioutil"
    "net/http"
    "strings"
)

func main() {
    url := "https://xxx"
    prama := "data=123456""
    tokenRes := GetTokenReq(url, prama)
    fmt.Println(tokenRes )
}

func GetTokenReq(url string, parama string) map[string]string {
    client := &http.Client{}
    req, err := http.NewRequest("POST", url, strings.NewReader(parama))
    req.Header.Add("Content-Type", "application/x-www-form-urlencoded")
    resp, err := client.Do(req)
    if err != nil {
        fmt.Println(err)
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        fmt.Println(err)
    }
    jsonStr := string(body)
    fmt.Println("jsonStr", jsonStr)
    var dat map[string]string
    if err := json.Unmarshal([]byte(jsonStr), &dat); err == nil {
        fmt.Println("access_token", dat["access_token"])
        fmt.Println("instance_url", dat["instance_url"])
    } else {
        fmt.Println("json str to struct error")
    }
    return dat
}