Golang 開発: 高パフォーマンスのデータベース接続プールの実装

package main

import (
    "database/sql"
    "fmt"
    "sync"

    _ "github.com/go-sql-driver/mysql"
)

type DBPool struct {
    queue chan *sql.DB
    wg    sync.WaitGroup
}

func NewDBPool(dataSourceName string, poolSize int) (*DBPool, error) {
    queue := make(chan *sql.DB, poolSize)
    for i := 0; i < poolSize; i++ {
        db, err := sql.Open("mysql", dataSourceName)
        if err != nil {
            return nil, err
        }
        queue <- db
    }
    return &DBPool{
        queue: queue,
    }, nil
}

func (p *DBPool) Get() *sql.DB {
    p.wg.Add(1)
    db := <-p.queue
    return db
}

func (p *DBPool) Put(db *sql.DB) {
    p.queue <- db
    p.wg.Done()
}

func main() {
    // 数据库连接信息
    dataSourceName := "username:password@tcp(localhost:3306)/database"

    // 创建数据库连接池
    pool, err := NewDBPool(dataSourceName, 10)
    if err != nil {
        fmt.Println("Failed to create DBPool:", err)
        return
    }

    // 从连接池获取连接
    conn := pool.Get()
    defer conn.Close()

    // 执行数据库操作
    rows, err := conn.Query("SELECT * FROM users")
    if err != nil {
        fmt.Println("Failed to query:", err)
        return
    }
    defer rows.Close()

    // 处理查询结果
    for rows.Next() {
        var id int
        var name string
        err = rows.Scan(&id, &name)
        if err != nil {
            fmt.Println("Failed to scan:", err)
            return
        }
        fmt.Println(id, name)
    }

    // 归还连接到连接池
    pool.Put(conn)

    // 等待所有连接释放
    pool.wg.Wait()
}