Golang实现基础投票系统教程

type Option struct {
    ID    int    `json:"id"`
    Text  string `json:"text"`
    Votes int    `json:"votes"`
}

type Poll struct {
    ID       int      `json:"id"`
    Question string   `json:"question"`
    Options  []Option `json:"options"`
}

var polls = make(map[int]*Poll)
var currentID = 1

func main() {
    http.HandleFunc("/polls", handlePolls)
    http.HandleFunc("/poll/", handlePollDetail)
    http.HandleFunc("/poll/vote", handleVote)
    http.ListenAndServe(":8080", nil)
}

func handlePolls(w http.ResponseWriter, r *http.Request) {
    if r.Method == "GET" {
        var result []*Poll
        for _, p := range polls {
            result = append(result, p)
        }
        json.NewEncoder(w).Encode(result)
    } else if r.Method == "POST" {
        var poll Poll
        json.NewDecoder(r.Body).Decode(&poll)
        poll.ID = currentID
        currentID++
        polls[poll.ID] = &poll
        w.WriteHeader(201)
        json.NewEncoder(w).Encode(poll)
    }
}

func handlePollDetail(w http.ResponseWriter, r *http.Request) {
    id, _ := strconv.Atoi(strings.TrimPrefix(r.URL.Path, "/poll/"))
    poll, exists := polls[id]
    if !exists {
        http.NotFound(w, r)
        return
    }
    json.NewEncoder(w).Encode(poll)
}

func handleVote(w http.ResponseWriter, r *http.Request) {
    type VoteReq struct {
        PollID     int `json:"poll_id"`
        OptionID   int `json:"option_id"`
    }

    var req VoteReq
    json.NewDecoder(r.Body).Decode(&req)

    poll, exists := polls[req.PollID]
    if !exists {
        http.Error(w, "Poll not found", 404)
        return
    }

    for i := range poll.Options {
        if poll.Options[i].ID == req.OptionID {
            poll.Options[i].Votes++
            json.NewEncoder(w).Encode(poll)
            return
        }
    }

    http.Error(w, "Option not found", 400)
}