如何利用Go语言开发点餐系统的顾客反馈功能

"database/sql"
"encoding/JSON"
"log"
"net/http"

"GitHub.com/gorilla/mux"
_ "github.com/go-sql-driver/Mysql"

ID         int    `json:"id,omitempty"`
CustomerID int    `json:"customer_id,omitempty"`
Content    string `json:"content,omitempty"`
Type       string `json:"type,omitempty"`
Rating     int    `json:"rating,omitempty"`
CreatedAt  string `json:"created_at,omitempty"`

w.Header().Set("Content-Type", "application/json")

var feedback Feedback
_ = json.NewDecoder(r.Body).Decode(&feedback)

insert, err := db.Query("INSERT INTO feedback (customer_id, content, type, rating) VALUES (?,?,?,?)", feedback.CustomerID, feedback.Content, feedback.Type, feedback.Rating)
if err != nil {
    log.Fatal(err)
}
defer insert.Close()

json.NewEncoder(w).Encode(feedback)

w.Header().Set("Content-Type", "application/json")

params := mux.Vars(r)
id := params["id"]

row := db.QueryRow("SELECT * FROM feedback WHERE id = ?", id)
var feedback Feedback
err := row.Scan(&feedback.ID, &feedback.CustomerID, &feedback.Content, &feedback.Type, &feedback.Rating, &feedback.CreatedAt)
if err != nil {
    log.Fatal(err)
}
json.NewEncoder(w).Encode(feedback)

w.Header().Set("Content-Type", "application/json")

var feedbacks []Feedback

rows, err := db.Query("SELECT * FROM feedback")
if err != nil {
    log.Fatal(err)
}

defer rows.Close()

for rows.Next() {
    var feedback Feedback
    err := rows.Scan(&feedback.ID, &feedback.CustomerID, &feedback.Content, &feedback.Type, &feedback.Rating, &feedback.CreatedAt)
    if err != nil {
        log.Fatal(err)
    }
    feedbacks = append(feedbacks, feedback)
}

json.NewEncoder(w).Encode(feedbacks)

router := mux.NewRouter().StrictSlash(true)

// Define routes
router.HandleFunc("/feedback", CreateFeedback).Methods("POST")
router.HandleFunc("/feedback/{id}", GetFeedbackByID).Methods("GET")
router.HandleFunc("/feedbacks", GetFeedbacks).Methods("GET")

// Open database connection
var err error
db, err = sql.Open("mysql", "username:passWord@tcp(localhost:3306)/database_name")
if err != nil {
    log.Fatal(err)
}

defer db.Close()

// Start server
log.Fatal(http.ListenAndServe(":8080", router))