以 Go 语言编写的 REST API 端点返回 JSON 对象

我正在使用 golang 构建 api。我希望此端点返回 json 数据，以便我可以在我的前端中使用它。

http.handlefunc("/api/orders", createorder)

目前我的函数没有返回 json 对象，并且 jsonmap 变量没有使用 create struc 将响应正文映射到服务器

我的结构

type createorder struct {
    id     string  `json:"id"`
    status string  `json:"status"`
    links  []links `json:"links"`
}

我的createorder函数（根据评论更新）

func createorder(w http.responsewriter, r *http.request) {
    accesstoken := generateaccesstoken()
    w.header().set("access-control-allow-origin", "*")
    fmt.println(accesstoken)

    body := []byte(`{
        "intent":"capture",
        "purchase_units":[
           {
              "amount":{
                 "currency_code":"usd",
                 "value":"100.00"
              }
           }
        ]
     }`)

    req, err := http.newrequest("post", base+"/v2/checkout/orders", bytes.newbuffer(body))
    req.header.set("content-type", "application/json")
    req.header.set("authorization", "bearer "+accesstoken)

    client := &http.client{}
    resp, err := client.do(req)

    if err != nil {
        log.fatalf("an error occured %v", err)
    }

    fmt.println(resp.statuscode)
    defer resp.body.close()

    if err != nil {
        log.fatal(err)
    }

    var jsonmap createorder

    error := json.newdecoder(resp.body).decode(&jsonmap)

    if error != nil {
        log.fatal(err)
    }

    w.writeheader(resp.statuscode)
    json.newencoder(w).encode(jsonmap)

}

这就是打印的内容。打印不带对象键的值

{2mh36251c2958825n created [{something self get} {soemthing approve get}]}

应该打印

{
  id: '8BW01204PU5017303',
  status: 'CREATED',
  links: [
    {
      href: 'url here',
      rel: 'self',
      method: 'GET'
    },
    ...
  ]
}

正确答案

func createorder(w http.responsewriter, r *http.request) {
    // ...

    resp, err := http.defaultclient.do(req)
    if err != nil {
        log.println("an error occured:", err)
        return
    }
    defer resp.body.close()
    
    if resp.statuscode != http.statusok /* or http.statuscreated (depends on the api you're using) */ {
        log.println("request failed with status:", http.status)
        w.writeheader(resp.statuscode)
        return
    }

    // decode response from external service
    v := new(createorder)
    if err := json.newdecoder(resp.body).decode(v); err != nil {
        log.println(err)
        return
    }
    
    // send response to frontend
    w.writeheader(resp.statuscode)
    if err := json.newencoder(w).encode(v); err != nil {
        log.println(err)
    }
}

或者，如果您想将数据从外部服务不变地发送到前端，您应该能够执行以下操作：

func createOrder(w http.ResponseWriter, r *http.Request) {
    // ...

    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        log.Println("An Error Occured:", err)
        return
    }
    defer resp.Body.Close()

    if resp.StatusCode != http.StatusOK /* or http.StatusCreated (depends on the API you're using) */ {
        log.Println("request failed with status:", http.Status)
        w.WriteHeader(resp.StatusCode)
        return
    }

    // copy response from external to frontend
    w.WriteHeader(resp.StatusCode)
    if _, err := io.Copy(w, resp.Body); err != nil {
        log.Println(err)
    }
}