Golang implements registration and login

In the Internet era, with the continuous advancement of Internet technology and people's increasing demand for information, the registration and login functions of websites and APPs have become more and more common. This article will introduce how to use golang language to implement the registration and login function.

1. Introduction to golang

Golang is a programming language developed by Google. It has the characteristics of efficient concurrent processing, automatic garbage collection, and extremely low compilation time. It has natural Concurrency capabilities and features suitable for large-scale systems. These features make golang a very excellent server-side language. Therefore, using it to implement the registration and login function is a very good choice.

2. Environment setup

To use golang to implement the registration and login function, you first need to install the golang language in the local environment. Before installation, you need to determine the operating system type of your computer (Windows, Linux, Mac, etc.), and select the corresponding golang version to download and install.

After the installation is completed, you can enter the following command on the command line to check whether the installation is successful:

go version

If the version number of golang is displayed, the installation is successful.

3. Registration function implementation

1. Create project folder

Create a folder named "login" to place this project document. Create two folders in this folder: controller and model. Among them, controller is used to place the controller code of the Web interface, and model is used to place the code of database operations.

2. Database connection and table creation

Create a file named "db.go" in the model folder, and write the following code in it to establish a database connection :

package model

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

const (
    USERNAME = "root"
    PASSWORD = ""
    NETWORK  = "tcp"
    SERVER   = "localhost"
    PORT     = 3306
    DATABASE = "login_system"
)

func DbConn() (db *sql.DB) {
    dbDriver := "mysql"
    dbUser := USERNAME
    dbPass := PASSWORD
    dbName := DATABASE
    db, err := sql.Open(dbDriver, dbUser+":"+dbPass+"@tcp("+SERVER+":"+strconv.Itoa(PORT)+")/"+dbName)
    if err != nil {
        fmt.Println("无法连接数据库：", err)
    } else {
        fmt.Println("成功连接数据库！")
    }
    return db
}

In the above code, the third-party library "go-sql-driver/mysql" is used to realize the database connection. In the code, we also need to set some basic information of the database, such as user name, password, host address, port number, database name, etc.

Next step, we need to create a file named "user.sql" to write the SQL statement to create the user table, which contains fields such as user ID, user name and password.

CREATE TABLE `user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(20) NOT NULL,
  `password` varchar(40) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

By executing the above SQL statement, the user table can be created in the database.

3. Write controller code

Create a file named "register.go" in the controller folder to write the controller code for the registration interface. In this file, you need to import the third-party library "net/http" and write the following code:

package controller

import (
    "crypto/md5"
    "database/sql"
    "encoding/hex"
    "fmt"
    "io/ioutil"
    "net/http"
    "server/model"
)

func Register(w http.ResponseWriter, r *http.Request) {
    if r.Method == "POST" {
        username := r.FormValue("username")
        password := r.FormValue("password")
        // 密码加密
        h := md5.New()
        h.Write([]byte(password))
        password = hex.EncodeToString(h.Sum(nil))
        // 数据库操作
        db := model.DbConn()
        defer db.Close()
        stmt, err := db.Prepare("INSERT INTO user(username, password) VALUES (?, ?)")
        if err != nil {
            fmt.Println("SQL语句执行失败：", err)
            return
        }
        _, err = stmt.Exec(username, password)
        if err != nil {
            fmt.Println("用户注册失败：", err)
            return
        }
        fmt.Println("用户注册成功！")
    }
    // 返回页面内容
    data, err := ioutil.ReadFile("register.html")
    if err != nil {
        fmt.Println("读取文件失败：", err)
        return
    }
    w.Write([]byte(data))
}

In the above code, we first determine whether the request method is POST. If it is a POST request, the user name and password are obtained, the password is MD5 encrypted, and the encrypted password and user name are stored in the database.

At the end of the file, use the ioutil.ReadFile() function to read a file named "register.html" and return the content of the file to the browser. In this way, the browser can display our registration interface.

4. Registration interface writing

Create a file named "register.html" in the login folder to write the code for the registration page. In this page, you need to use the

tag and tag to obtain the username and password information, and submit this information to the backend for processing. The specific code is as follows:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>注册</title>
</head>
<body>
    <form action="/register" method="post">
        <p>用户名：<input type="text" name="username" /></p>
        <p>密码：<input type="password" name="password" /></p>
        <input type="submit" value="注册" />
    </form>
</body>
</html>

In the above code, the action attribute of the tag represents the submission address of the form, which is the URL address of the registration interface, and the method attribute represents the submission method of the form, that is, using POST method submission.

5. Start the server

Create a file named "main.go" in the login folder to start the server. In this file, you need to import the third-party library "net/http" and write the following code:

package main

import (
    "net/http"
    "login/controller"
)

func main() {
    // 注册接口路由
    http.HandleFunc("/register", controller.Register)
    // 启动服务器
    http.ListenAndServe(":8080", nil)
}

In the above code, we use the http.HandleFunc() function to specify the routing address for the registration interface. After the program is started, you can access "http://localhost:8080/register" through the browser to open the registration interface.

4. Login function implementation

1. Writing controller code

Create a file named "login.go" in the controller folder. Used to write controller code for the login interface. In this file, you need to import the third-party libraries "net/http" and "database/sql" and write the following code:

package controller

import (
    "crypto/md5"
    "database/sql"
    "encoding/hex"
    "fmt"
    "io/ioutil"
    "net/http"
    "server/model"    
)

func Login(w http.ResponseWriter, r *http.Request) {
    if r.Method == "POST" {
        username := r.FormValue("username")
        password := r.FormValue("password")
        h := md5.New()
        h.Write([]byte(password))
        password = hex.EncodeToString(h.Sum(nil))
        // 根据用户名和密码查询数据库
        db := model.DbConn()
        defer db.Close()
        rows, err := db.Query("SELECT * FROM user WHERE username=? AND password=?", username, password)
        if err != nil {
            fmt.Println("SQL语句执行失败：", err)
            return
        }
        defer rows.Close()
        if rows.Next() {
            fmt.Println("登录成功！")
            // 返回登录成功页面
            data, err := ioutil.ReadFile("success.html")
            if err != nil {
                fmt.Println("读取文件失败：", err)
                return
            }
            w.Write([]byte(data))
        } else {
            fmt.Println("用户名或密码不正确！")
            // 返回登录失败页面
            data, err := ioutil.ReadFile("fail.html")
            if err != nil {
                fmt.Println("读取文件失败：", err)
                return
            }
            w.Write([]byte(data))
        }
    }
    // 返回登录页面
    data, err := ioutil.ReadFile("login.html")
    if err != nil {
        fmt.Println("读取文件失败：", err)
        return
    }
    w.Write([]byte(data))
}

In the above code, we first determine whether the request method is POST. If it is a POST request, the username and password are obtained, and the password is encrypted with MD5. Then, we query the database based on the username and password. If the query result is not empty, it means the login is successful, otherwise it means the login failed.

At the end of the file, we read two more files named "success.html" and "fail.html", which are used to represent the page content after successful and failed login respectively.

2. Login interface writing

Create a file named "login.html" in the login folder to write the code for the login page. This page is similar to the registration page. It also needs to use the tag and tag to obtain the username and password information, and submit this information to the backend for processing. The specific code is as follows:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>登录</title>
</head>
<body>
    <form action="/login" method="post">
        <p>用户名：<input type="text" name="username" /></p>
        <p>密码：<input type="password" name="password" /></p>
        <input type="submit" value="登录" />
    </form>
</body>
</html>

3. 成功和失败页面编写

在login文件夹中创建一个名为“success.html”的文件，用来编写登录成功后的页面代码。具体代码如下：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>登录成功</title>
</head>
<body>
    <h1>恭喜，登录成功！</h1>
</body>
</html>

在login文件夹中再创建一个名为“fail.html”的文件，用来编写登录失败后的页面代码。具体代码如下：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>登录失败</title>
</head>
<body>
    <h1>对不起，用户名或密码错误！</h1>
</body>
</html>

4. 注册接口路由修改

在“main.go”文件中，将注册接口路由的地址改为“/”即可。最终代码如下：

package main

import (
    "net/http"
    "login/controller"
)

func main() {
    // 注册接口路由
    http.HandleFunc("/", controller.Register)
    // 登录接口路由
    http.HandleFunc("/login", controller.Login)
    // 启动服务器
    http.ListenAndServe(":8080", nil)
}

五、总结

本文介绍了如何使用golang语言来实现注册登录功能。通过本文的学习，我们可以看到golang语言实现简洁高效、性能优越，适合用于实现服务器端开发。同时，本文也向读者展示了如何使用golang与数据库进行交互，以及如何使用golang实现Web接口的功能。希望本文能够为读者带来一些参考和启发。

The above is the detailed content of Golang implements registration and login. For more information, please follow other related articles on the PHP Chinese website!