如何发送动态JSON键/值作为请求参数

Question

package main

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

func main() {
    j := `{"url":"http://localhost/test/take-request", "params":{"name":"John","age":"20"},"type":"get"}`
    // k := `{"url":"http://localhost/test/take-request", "params":{"gender":"m","a":"20"},"type":"post"}`

    request := map[string]interface{}{}

    err := json.Unmarshal([]byte(j), &request)
    if err != nil {
        panic(err)
    }
    fmt.Println(request)
    requestType = strings.ToUpper(request["type"]);
    requestUrl = request["url"];

    fmt.Println(request["params"])

    // how do i get the keys and their values from params.
    // note params is dynamic.
    for _, v := range request["params"].(map[string]interface{}) {
        // println(v)

        switch t := v.(type) {
        case string, []int:
            fmt.Println(t)
        default:
            fmt.Println("wrong type")
        }
    }

    sendRequest(requestType, requestUrl)
}

func sendRequest(type string, url string) string {
    req, err := http.NewRequest(type, url, nil)
    client := &http.Client{}
    resp, err := client.Do(req)
    if err != nil {
        panic(err)
    }
    defer resp.Body.Close()

    body, _ := ioutil.ReadAll(resp.Body)
    fmt.Println("response Body:", string(body))
    return string(body)
}

1. How do I iterate through params that is an interface
2. how do i get the key and its values

Answer 1

You can greatly simplify your code by using a proper struct for your JSON unmarshaling:

type Request struct {
    URL    string                 `json:"url"`
    Params map[string]interface{} `json:"params"`
    Type   string                 `json:"type"`
}

Then you can unmarshal it more simply as so:

request := &Request{}
if err := json.Unmarshal([]byte(j), &request); err != nil {
    panic(err)
}

And access the values as such:

requestType = request.Type
requestURL = request.URL
for key, value := range request.Params {
    switch v := value.(type) {
    case float64:
         // handle numbers
    case string:
         // handle strings
    }
}