玩转spring boot——简单登录认证

前言

---

在一个web项目中，某些页面是可以匿名访问的，但有些页面则不能。spring mvc提供了HandlerInterceptor接口来应对,只需要重写preHandle方法便可以实现此功能。那么使用spring boot是怎么实现的呢？

一、准备工作

---

pom.xml：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.github.carter659</groupId>
    <artifactId>spring13</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.3.RELEASE</version>
    </parent>

    <name>spring13</name>
    <url>http://maven.apache.org</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
    </dependencies>


    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

与以往的pom.xml没有任何不同

App.java

package com.github.carter659.spring13;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * 入口类 博客出处：http://www.cnblogs.com/GoodHelper/
 *
 */
@SpringBootApplication
public class App {

    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }
}

二、具体实现

---

1.新建控制器“MainController”文件：

package com.github.carter659.spring13;

import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.SessionAttribute;

/**
 * 控制器 博客出处：http://www.cnblogs.com/GoodHelper/
 *
 */
@Controller
public class MainController {

    @GetMapping("/")
    public String index(@SessionAttribute(WebSecurityConfig.SESSION_KEY) String account, Model model) {
        model.addAttribute("name", account);
        return "index";
    }

    @GetMapping("/login")
    public String login() {
        return "login";
    }

    @PostMapping("/loginPost")
    public @ResponseBody Map<String, Object> loginPost(String account, String password, HttpSession session) {
        Map<String, Object> map = new HashMap<>();
        if (!"123456".equals(password)) {
            map.put("success", false);
            map.put("message", "密码错误");
            return map;
        }

        // 设置session
        session.setAttribute(WebSecurityConfig.SESSION_KEY, account);

        map.put("success", true);
        map.put("message", "登录成功");
        return map;
    }

    @GetMapping("/logout")
    public String logout(HttpSession session) {
        // 移除session
        session.removeAttribute(WebSecurityConfig.SESSION_KEY);
        return "redirect:/login";
    }

}

讲解MainController：

这里的四个方法分别是：登录后的页面、登录页面、登录ajax后台方法和注销。

“loginPost”方法判断当密码为“123456”时则设置session

“index”方法用来显示session

“logout”方法用来移除session

2.新建“WebSecurityConfig”类文件：

package com.github.carter659.spring13;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

/**
 * 登录配置 博客出处：http://www.cnblogs.com/GoodHelper/
 *
 */
@Configuration
public class WebSecurityConfig extends WebMvcConfigurerAdapter {

    /**
     * 登录session key
     */
    public final static String SESSION_KEY = "user";

    @Bean
    public SecurityInterceptor getSecurityInterceptor() {
        return new SecurityInterceptor();
    }

    public void addInterceptors(InterceptorRegistry registry) {
        InterceptorRegistration addInterceptor = registry.addInterceptor(getSecurityInterceptor());

        // 排除配置
        addInterceptor.excludePathPatterns("/error");
        addInterceptor.excludePathPatterns("/login**");

        // 拦截配置
        addInterceptor.addPathPatterns("/**");
    }

    private class SecurityInterceptor extends HandlerInterceptorAdapter {

        @Override
        public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
                throws Exception {
            HttpSession session = request.getSession();
            if (session.getAttribute(SESSION_KEY) != null)
                return true;

            // 跳转登录
            String url = "/login";
            response.sendRedirect(url);
            return false;
        }
    }
}

“SecurityInterceptor”类继承“HandlerInterceptorAdapter”，并重新“preHandle”方法，当session为空时，则跳转到登录页面

“WebSecurityConfig”类继承“WebMvcConfigurerAdapter”，重新“addInterceptors”方法，其目的是设置拦截规则，excludePathPatterns为需要排除的规则，addPathPatterns为需要拦截的规则。

三、页面

---

index.html：

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>玩转spring boot——简单登录认证</title>
</head>
<body>
    <h1>玩转spring boot——简单登录认证</h1>
    <h4>
        <a href="http://www.cnblogs.com/GoodHelper/">from 刘冬的博客</a>
    </h4>
    <h3 th:text="'登录用户：' + ${name}"></h3>
    
    <a href="/logout">注销</a>
    <br />
    <a href="http://www.cnblogs.com/GoodHelper/">点击访问原版博客(www.cnblogs.com/GoodHelper)</a>
</body>
</html>

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>玩转spring boot——简单登录认证</title>
</head>
<body>
    <h1>玩转spring boot——简单登录认证</h1>
    <h4>
        <a href="http://www.cnblogs.com/GoodHelper/">from 刘冬的博客</a>
    </h4>
    <h3 th:text="'登录用户：' + ${name}"></h3>
    
    <a href="/logout">注销</a>
    <br />
    <a href="http://www.cnblogs.com/GoodHelper/">点击访问原版博客(www.cnblogs.com/GoodHelper)</a>
</body>
</html>

四、运行效果

---

1.输入错误的密码后无法登陆

2.输入正确密码后调整到首页

3.在首页显示了登录后的账号

4.点击注销后返回登录页面

5.在未登录的情况下，直接输入首页网站“http://localhost:8080”后，无法进入首页，会强制跳转到登录页面。