如何利用MySQL和Go語言開發一個簡單的日誌管理系統

$ mkdir log_management_system
$ cd log_management_system
$ go mod init log_management_system

package main

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

func main() {
    db, err := sql.Open("mysql", "root:password@tcp(localhost:3306)/log?charset=utf8")
    if err != nil {
        panic(err.Error())
    }
    defer db.Close()
  
    err = db.Ping()
    if err != nil {
        panic(err.Error())
    }
  
    fmt.Println("Successfully connected to MySQL database")
    // 后续代码将在此处编写
}

CREATE TABLE logs (
    id INT AUTO_INCREMENT PRIMARY KEY,
    level VARCHAR(10) NOT NULL,
    message VARCHAR(255) NOT NULL,
    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
);

func main() {
    // 数据库连接代码...

    _, err = db.Exec(`CREATE TABLE IF NOT EXISTS logs (
        id INT AUTO_INCREMENT PRIMARY KEY,
        level VARCHAR(10) NOT NULL,
        message VARCHAR(255) NOT NULL,
        created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
    )`)
    if err != nil {
        panic(err.Error())
    }

    fmt.Println("Successfully created logs table")
    // 后续代码将在此处编写
}

func insertLog(db *sql.DB, level string, message string) error {
    _, err := db.Exec(`INSERT INTO logs (level, message) VALUES (?, ?)`, level, message)
    return err
}

func queryLogs(db *sql.DB) ([]Log, error) {
    rows, err := db.Query(`SELECT * FROM logs ORDER BY created_at DESC`)
    if err != nil {
        return nil, err
    }
  
    defer rows.Close()
  
    logs := []Log{}
    for rows.Next() {
        var log Log
        err := rows.Scan(&log.ID, &log.Level, &log.Message, &log.CreatedAt)
        if err != nil {
            return nil, err
        }
      
        logs = append(logs, log)
    }
  
    return logs, nil
}

type Log struct {
    ID        int
    Level     string
    Message   string
    CreatedAt time.Time
}

func main() {
    // 数据库连接代码与创建日志表代码...
  
    err = insertLog(db, "INFO", "This is an info message")
    if err != nil {
        panic(err.Error())
    }
  
    logs, err := queryLogs(db)
    if err != nil {
        panic(err.Error())
    }
  
    for _, log := range logs {
        fmt.Printf("ID: %d, Level: %s, Message: %s, CreatedAt: %s
", log.ID, log.Level, log.Message, log.CreatedAt)
    }
}