spring security如何集成token请用代码说明

当使用Spring Security进行身份验证和授权时，可以通过集成令牌(token)来增强安全性。以下是一个示例代码，演示了如何集成基于令牌的身份验证和授权。

首先，需要添加相关的依赖项到项目的构建文件（例如pom.xml）中：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-security</artifactId>
</dependency>

<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt</artifactId>
    <version>0.9.1</version>
</dependency>

接下来，创建一个用于生成和解析令牌的TokenProvider类：

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import java.util.Date;

@Component
public class TokenProvider {

    @Value("${app.jwtSecret}")
    private String jwtSecret;

    @Value("${app.jwtExpirationInMs}")
    private int jwtExpirationInMs;

    public String generateToken(String username) {
        Date now = new Date();
        Date expiryDate = new Date(now.getTime() + jwtExpirationInMs);

        return Jwts.builder()
                .setSubject(username)
                .setIssuedAt(new Date())
                .setExpiration(expiryDate)
                .signWith(SignatureAlgorithm.HS512, jwtSecret)
                .compact();
    }

    public String getUsernameFromToken(String token) {
        Claims claims = Jwts.parser()
                .setSigningKey(jwtSecret)
                .parseClaimsJws(token)
                .getBody();

        return claims.getSubject();
    }

    public boolean validateToken(String token) {
        try {
            Jwts.parser().setSigningKey(jwtSecret).parseClaimsJws(token);
            return true;
        } catch (Exception ex) {
            return false;
        }
    }
}

在上述代码中，TokenProvider类包含了生成令牌、解析令牌和验证令牌的方法。需要注意的是，需要在配置文件(application.properties或application.yml)中配置jwtSecret和jwtExpirationInMs属性。

然后，创建一个用于处理身份验证和授权的SecurityConfig类：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpMethod;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.method.configuration.EnableGlobalMethodSecurity;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;

@Configuration
@EnableWebSecurity
@EnableGlobalMethodSecurity(prePostEnabled = true)
public class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Autowired
    private CustomUserDetailsService customUserDetailsService;

    @Autowired
    private JwtAuthenticationEntryPoint unauthorizedHandler;

    @Bean
    public JwtAuthenticationFilter jwtAuthenticationFilter() {
        return new JwtAuthenticationFilter();
    }

    @Override
    public void configure(AuthenticationManagerBuilder authenticationManagerBuilder) throws Exception {
        authenticationManagerBuilder
                .userDetailsService(customUserDetailsService)
                .passwordEncoder(passwordEncoder());
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
                .cors()
                    .and()
                .csrf()
                    .disable()
                .exceptionHandling()
                    .authenticationEntryPoint(unauthorizedHandler)
                    .and()
                .sessionManagement()
                    .sessionCreationPolicy(SessionCreationPolicy.STATELESS)
                    .and()
                .authorizeRequests()
                    .antMatchers("/api/auth/**").permitAll()
                    .anyRequest().authenticated();

        http.addFilterBefore(jwtAuthenticationFilter(), UsernamePasswordAuthenticationFilter.class);
    }

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }

    @Bean
    @Override
    public AuthenticationManager authenticationManagerBean() throws Exception {
        return super.authenticationManagerBean();
    }
}

在上述代码中，SecurityConfig类继承了WebSecurityConfigurerAdapter，并覆盖了configure方法。通过配置HttpSecurity，我们可以定义哪些URL需要进行身份验证和授权。

最后，创建一个用于处理用户详情的CustomUserDetailsService类：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Service;

@Service
public class CustomUserDetailsService implements UserDetailsService {

    @Autowired
    private UserRepository userRepository;

    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
        User user = userRepository.findByUsername(username)
                .orElseThrow(() -> new UsernameNotFoundException("User not found with username: " + username));

        return UserPrincipal.create(user);
    }
}

在上述代码中，CustomUserDetailsService类实现了UserDetailsService接口，并覆盖了loadUserByUsername方法。该方法根据用户名从数据库中加载用户信息。

这样，我们就完成了Spring Security与令牌的集成。可以使用TokenProvider类生成和解析令牌，使用SecurityConfig类配置身份验证和授权规则，使用CustomUserDetailsService类加载用户信息。