package main

import (
    "bytes"
    "encoding/json"
    "fmt"
    "net/http"
)

const (
    corpid     = "企业代号"
    agentId    = "1000004"
    corpsecret = "企业密钥"
)

func httpGetJson(url string) (map[string]interface{}, error) {
    resp, err := http.Get(url)
    if err != nil {
        return nil, err
    }
    defer resp.Body.Close()

    var data map[string]interface{}
    err = json.NewDecoder(resp.Body).Decode(&data)
    if err != nil {
        return nil, err
    }

    return data, nil
}

func httpPostJson(url string, data map[string]interface{}) (map[string]interface{}, error) {
    xxx, err := json.Marshal(data)
    if err != nil {
        return nil, err
    }

    resp, err := http.Post(url, "application/json", bytes.NewReader(xxx))
    if err != nil {
        return nil, err
    }
    defer resp.Body.Close()

    var data2 map[string]interface{}
    err = json.NewDecoder(resp.Body).Decode(&data)
    if err != nil {
        return nil, err
    }

    return data2, nil
}

func main() {
    url := fmt.Sprintf("https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=%s&corpsecret=%s", corpid, corpsecret)
    data, err := httpGetJson(url)
    if err != nil {
        fmt.Println(err)
        return
    }

    errcode := data["errcode"].(float64)
    if errcode != 0 {
        fmt.Println("errcode: ", errcode)
        return
    }
    access_token := data["access_token"]

    req := map[string]interface{}{
        "touser":  "@all",
        "msgtype": "text",
        "agentid": agentId,
        "text": map[string]interface{}{
            "content": "hello",
        },
    }

    url = fmt.Sprintf("https://qyapi.weixin.qq.com/cgi-bin/message/send?access_token=%s", access_token)
    data, err = httpPostJson(url, req)
    if err != nil {
        fmt.Println(err)
        return
    }

    fmt.Println("ok")
}