springsecurity整合jwt实现登录认证代码示例

好的，以下是一个简单的 Spring Security 整合 JWT 实现登录认证的代码示例：

首先，需要添加以下依赖：

<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt-api</artifactId>
    <version>0.11.2</version>
</dependency>
<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt-impl</artifactId>
    <version>0.11.2</version>
    <scope>runtime</scope>
</dependency>
<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt-jackson</artifactId>
    <version>0.11.2</version>
    <scope>runtime</scope>
</dependency>

接着，定义一个 JWT 工具类，用于生成和解析 JWT：

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 JwtUtils {

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

    @Value("${jwt.expiration}")
    private Long expiration;

    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 expirationDate = new Date(now.getTime() + expiration * 1000);
        return Jwts.builder()
                .setClaims(claims)
                .setSubject(subject)
                .setIssuedAt(now)
                .setExpiration(expirationDate)
                .signWith(SignatureAlgorithm.HS256, secret)
                .compact();
    }

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

    public String getUsernameFromToken(String token) {
        return getClaimFromToken(token, Claims::getSubject);
    }

    public Date getExpirationDateFromToken(String token) {
        return getClaimFromToken(token, Claims::getExpiration);
    }

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

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

    private Boolean isTokenExpired(String token) {
        final Date expiration = getExpirationDateFromToken(token);
        return expiration.before(new Date());
    }
}

其中，`${jwt.secret}` 和 `${jwt.expiration}` 是从配置文件中读取的 JWT 密钥和过期时间。

然后，在 `WebSecurityConfig` 中配置 JWT 认证：

import org.springframework.beans.factory.annotation.Autowired;
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.builders.WebSecurity;
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.password.PasswordEncoder;
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;

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

    @Autowired
    private JwtAuthenticationEntryPoint jwtAuthenticationEntryPoint;

    @Autowired
    private JwtUserDetailsService jwtUserDetailsService;

    @Autowired
    private JwtRequestFilter jwtRequestFilter;

    @Autowired
    private PasswordEncoder passwordEncoder;

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

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.csrf().disable()
                .authorizeRequests()
                .antMatchers("/api/authenticate").permitAll()
                .antMatchers(HttpMethod.OPTIONS, "/**").permitAll()
                .anyRequest().authenticated()
                .and()
                .exceptionHandling().authenticationEntryPoint(jwtAuthenticationEntryPoint)
                .and()
                .sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS);
        http.addFilterBefore(jwtRequestFilter, UsernamePasswordAuthenticationFilter.class);
    }

    @Override
    public void configure(WebSecurity web) throws Exception {
        web.ignoring().antMatchers("/resources/**", "/static/**", "/css/**", "/js/**", "/images/**");
    }

    @Override
    protected AuthenticationManager authenticationManager() throws Exception {
        return super.authenticationManager();
    }
}

其中，`JwtAuthenticationEntryPoint` 是自定义的未授权处理器，`JwtUserDetailsService` 是自定义的用户详情服务，`JwtRequestFilter` 是自定义的 JWT 过滤器。

最后，定义一个控制器来处理登录请求：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.web.bind.annotation.*;

import javax.validation.Valid;

@RestController
@RequestMapping("/api")
public class JwtAuthenticationController {

    @Autowired
    private AuthenticationManager authenticationManager;

    @Autowired
    private JwtUtils jwtUtils;

    @Autowired
    private JwtUserDetailsService jwtUserDetailsService;

    @PostMapping("/authenticate")
    public ResponseEntity<?> authenticate(@Valid @RequestBody JwtRequest jwtRequest) throws Exception {
        try {
            authenticationManager.authenticate(
                    new UsernamePasswordAuthenticationToken(jwtRequest.getUsername(), jwtRequest.getPassword()));
        } catch (AuthenticationException e) {
            throw new UsernameNotFoundException("Invalid username or password");
        }

        final UserDetails userDetails = jwtUserDetailsService.loadUserByUsername(jwtRequest.getUsername());
        final String token = jwtUtils.generateToken(userDetails);

        return ResponseEntity.ok(new JwtResponse(token));
    }
}

其中，`JwtRequest` 是自定义的请求实体类，`JwtResponse` 是自定义的响应实体类。

这样，就完成了 Spring Security 整合 JWT 实现登录认证的代码示例。