spring security整合jwt代码示例

好的，以下是一个简单的 Spring Security 整合 JWT 的代码示例：

1. 首先，添加依赖：

<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>

2. 创建一个 JWT 工具类：

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

import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.function.Function;

@Component
public class JwtUtil {

    @Value("${jwt.secret}")
    private String SECRET_KEY;

    public String generateToken(UserDetails userDetails) {
        Map<String, Object> claims = new HashMap<>();
        return createToken(claims, userDetails.getUsername());
    }

    private String createToken(Map<String, Object> claims, String subject) {
        Date now = new Date();
        Date expiration = new Date(now.getTime() + 1000 * 60 * 60 * 10); // 10 hours
        return Jwts.builder()
                .setClaims(claims)
                .setSubject(subject)
                .setIssuedAt(now)
                .setExpiration(expiration)
                .signWith(SignatureAlgorithm.HS256, SECRET_KEY)
                .compact();
    }

    public boolean validateToken(String token, UserDetails userDetails) {
        final String username = extractUsername(token);
        return (username.equals(userDetails.getUsername()) && !isTokenExpired(token));
    }

    public boolean isTokenExpired(String token) {
        return extractExpiration(token).before(new Date());
    }

    public String extractUsername(String token) {
        return extractClaim(token, Claims::getSubject);
    }

    public Date extractExpiration(String token) {
        return extractClaim(token, Claims::getExpiration);
    }

    public <T> T extractClaim(String token, Function<Claims, T> claimsResolver) {
        final Claims claims = extractAllClaims(token);
        return claimsResolver.apply(claims);
    }

    private Claims extractAllClaims(String token) {
        return Jwts.parser().setSigningKey(SECRET_KEY).parseClaimsJws(token).getBody();
    }
}

3. 创建一个 JWT 认证过滤器：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
import org.springframework.stereotype.Component;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Component
public class JwtAuthenticationFilter extends AbstractAuthenticationProcessingFilter {

    @Autowired
    private JwtUtil jwtUtil;

    public JwtAuthenticationFilter(AuthenticationManager authenticationManager) {
        super(new AntPathRequestMatcher("/api/login"));
        setAuthenticationManager(authenticationManager);
    }

    @Override
    public Authentication attemptAuthentication(HttpServletRequest request,
                                                HttpServletResponse response) throws AuthenticationException {
        String username = request.getParameter("username");
        String password = request.getParameter("password");

        return getAuthenticationManager().authenticate(
                new UsernamePasswordAuthenticationToken(username, password)
        );
    }

    @Override
    protected void successfulAuthentication(HttpServletRequest request, HttpServletResponse response,
                                            FilterChain chain, Authentication authResult) throws IOException, ServletException {
        String token = jwtUtil.generateToken((UserDetailsImpl) authResult.getPrincipal());
        response.setHeader("Authorization", "Bearer " + token);
    }

    @Override
    protected void unsuccessfulAuthentication(HttpServletRequest request, HttpServletResponse response, AuthenticationException failed) throws IOException, ServletException {
        response.sendError(HttpServletResponse.SC_UNAUTHORIZED, "Unauthorized");
    }
}

4. 在 Spring Security 配置中添加 JWT 认证过滤器：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
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.core.userdetails.UserDetailsService;
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 UserDetailsService userDetailsService;

    @Autowired
    private JwtAuthenticationFilter jwtAuthenticationFilter;

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(userDetailsService).passwordEncoder(passwordEncoder());
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.csrf().disable()
                .authorizeRequests()
                .antMatchers("/api/login").permitAll()
                .anyRequest().authenticated()
                .and()
                .addFilter(jwtAuthenticationFilter)
                .sessionManagement().disable();
    }

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

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

这样，就完成了 Spring Security 和 JWT 的整合。当用户登录时，会生成一个 JWT Token 并返回给客户端，客户端在后续的请求中需要携带该 Token 进行认证。你可以根据自己的需求，在代码中进行适当的修改。