使用Go（golang），如何将数据解组到结构中，然后从结构中调用特定字段？

Question

I'm trying to do an API request to get some information from steams public API (this is mainly for learning Go and just learning how to deal with Json / API requests) I have gotten this code so far:

package main

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

type SteamAPI struct {
    APIKey string
}

type GetAppNews struct {
    AppNews struct {
        AppId     int `json:"appid"`
        NewsItems []struct {
            Gid           int    `json:"gid"`
            Title         string `json:"title"`
            Url           string `json:"url"`
            IsExternalUrl bool   `json:"is_external_url"`
            Author        string `json:"author"`
            Contents      string `json:"contents"`
            Feedlabel     string `json:"feedlabel"`
            Date          int    `json:"date"`
        } `json:"newsitems"`
    } `json:"appnews"`
}

type JsonResponse map[string]GetAppNews

func (s SteamAPI) GetNewsForApp(appid, count, maxlength int) error {
    sAppid := strconv.Itoa(appid)
    sCount := strconv.Itoa(count)
    sMaxlength := strconv.Itoa(maxlength)

    resp, err := http.Get("http://api.steampowered.com/ISteamNews/GetNewsForApp/v0002/?appid=" + sAppid + "&count=" + sCount + "&maxlength=" + sMaxlength + "&format=json")
    if err != nil {
        return err
    }

    defer resp.Body.Close()

    body, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        return err
    }

    var jsonReturn JsonResponse

    json.Unmarshal(body, &jsonReturn)

    fmt.Println(jsonReturn)

    return nil

}

func main() {
        Tester := SteamAPI{""}

        Tester.GetNewsForApp(440, 3, 300)
}

Things seem to work, alright, I guess but its not formatting it the way I would expect it to Unmarshal. It prints out like this:

map[appnews:{{0 []}}]

You can click here to see exactly what the format of the JSON response looks like, if anybody could tell me what I have done wrong with my struct, in the end I expect to be able to go something like:

fmt.Println(blah["appnews"]["appid"]) and it would return 440.

Thats all I really got to go off of, if you need anymore specific information let me know! Thanks for the help!

Answer 1

The data fits the struct just fine, no need for map[string]GetAppNews.

type JsonResponse map[string]GetAppNews should just be GetAppNews.

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