Go 言語を使用して、訪問調理システムでユーザー フィードバック モジュールを作成するにはどうすればよいですか?

id INT AUTO_INCREMENT PRIMARY KEY,
userId INT NOT NULL,
content TEXT NOT NULL,
createTime TIMESTAMP DEFAULT CURRENT_TIMESTAMP

"database/sql"
"fmt"
_ "github.com/go-sql-driver/mysql"

db, err := sql.Open("mysql", "root:password@tcp(127.0.0.1:3306)/feedback")
if err != nil {
    return nil, fmt.Errorf("failed to connect to database: %v", err)
}

err = db.Ping()
if err != nil {
    return nil, fmt.Errorf("failed to ping database: %v", err)
}

return db, nil

"database/sql"
"fmt"
"time"

ID        int
UserID    int
Content   string
CreateTime time.Time

stmt, err := db.Prepare("INSERT INTO feedback(userId, content) VALUES(?, ?)")
if err != nil {
    return fmt.Errorf("failed to prepare insert statement: %v", err)
}
defer stmt.Close()

_, err = stmt.Exec(feedback.UserID, feedback.Content)
if err != nil {
    return fmt.Errorf("failed to execute insert statement: %v", err)
}

return nil

rows, err := db.Query("SELECT * FROM feedback")
if err != nil {
    return nil, fmt.Errorf("failed to execute query: %v", err)
}
defer rows.Close()

feedbacks := make([]*Feedback, 0)
for rows.Next() {
    feedback := &Feedback{}
    err := rows.Scan(&feedback.ID, &feedback.UserID, &feedback.Content, &feedback.CreateTime)
    if err != nil {
        return nil, fmt.Errorf("failed to scan feedback: %v", err)
    }
    feedbacks = append(feedbacks, feedback)
}

return feedbacks, nil

"encoding/json"
"log"
"net/http"

db, err := ConnectDB()
if err != nil {
    log.Fatalf("failed to connect to database: %v", err)
}
defer db.Close()

http.HandleFunc("/feedback", func(w http.ResponseWriter, r *http.Request) {
    switch r.Method {
    case http.MethodGet:
        feedbacks, err := GetFeedbacks(db)
        if err != nil {
            log.Printf("failed to get feedbacks: %v", err)
            http.Error(w, "Internal server error", http.StatusInternalServerError)
            return
        }

        json.NewEncoder(w).Encode(feedbacks)
    case http.MethodPost:
        var feedback Feedback
        err := json.NewDecoder(r.Body).Decode(&feedback)
        if err != nil {
            log.Printf("failed to decode feedback: %v", err)
            http.Error(w, "Bad request", http.StatusBadRequest)
            return
        }

        err = InsertFeedback(db, &feedback)
        if err != nil {
            log.Printf("failed to insert feedback: %v", err)
            http.Error(w, "Internal server error", http.StatusInternalServerError)
            return
        }

        w.WriteHeader(http.StatusCreated)
    default:
        http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
    }
})

log.Println("Server listening on :8000")
log.Fatal(http.ListenAndServe(":8000", nil))