JWT Authentication

title: JWT Authentication in Spring Boot description: JSON Web Token based authentication

Stateless authentication using JSON Web Tokens.

Dependency

xml exampleWoHoTech

<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt-api</artifactId>
    <version>0.12.3</version>
</dependency>

JWT Utility Class

java exampleWoHoTech

@Component
public class JwtUtils {
    @Value("${app.jwt.secret}")
    private String jwtSecret;

    @Value("${app.jwt.expiration:86400000}") // 24 hours
    private long jwtExpiration;

    public String generateToken(String username) {
        return Jwts.builder()
            .subject(username)
            .issuedAt(new Date())
            .expiration(new Date(System.currentTimeMillis() + jwtExpiration))
            .signWith(getSigningKey())
            .compact();
    }

    public String extractUsername(String token) {
        return getClaims(token).getSubject();
    }

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

    private boolean isTokenExpired(String token) {
        return getClaims(token).getExpiration().before(new Date());
    }

    private Claims getClaims(String token) {
        return Jwts.parser().verifyWith(getSigningKey()).build().parseSignedClaims(token).getPayload();
    }

    private SecretKey getSigningKey() {
        return Keys.hmacShaKeyFor(Decoders.BASE64.decode(jwtSecret));
    }
}

Auth Controller

java exampleWoHoTech

@RestController
@RequestMapping("/api/auth")
public class AuthController {
    @Autowired AuthenticationManager authManager;
    @Autowired JwtUtils jwtUtils;

    @PostMapping("/login")
    public ResponseEntity<?> login(@RequestBody LoginRequest req) {
        Authentication auth = authManager.authenticate(
            new UsernamePasswordAuthenticationToken(req.getEmail(), req.getPassword()));
        String token = jwtUtils.generateToken(req.getEmail());
        return ResponseEntity.ok(Map.of("token", token, "type", "Bearer"));
    }
}

title: JWT Authentication in Spring Boot description: JSON Web Token based authentication

Stateless authentication using JSON Web Tokens.

Dependency

xml exampleWoHoTech

<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt-api</artifactId>
    <version>0.12.3</version>
</dependency>

JWT Utility Class

java exampleWoHoTech

@Component
public class JwtUtils {
    @Value("${app.jwt.secret}")
    private String jwtSecret;

    @Value("${app.jwt.expiration:86400000}") // 24 hours
    private long jwtExpiration;

    public String generateToken(String username) {
        return Jwts.builder()
            .subject(username)
            .issuedAt(new Date())
            .expiration(new Date(System.currentTimeMillis() + jwtExpiration))
            .signWith(getSigningKey())
            .compact();
    }

    public String extractUsername(String token) {
        return getClaims(token).getSubject();
    }

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

    private boolean isTokenExpired(String token) {
        return getClaims(token).getExpiration().before(new Date());
    }

    private Claims getClaims(String token) {
        return Jwts.parser().verifyWith(getSigningKey()).build().parseSignedClaims(token).getPayload();
    }

    private SecretKey getSigningKey() {
        return Keys.hmacShaKeyFor(Decoders.BASE64.decode(jwtSecret));
    }
}

Auth Controller

java exampleWoHoTech

@RestController
@RequestMapping("/api/auth")
public class AuthController {
    @Autowired AuthenticationManager authManager;
    @Autowired JwtUtils jwtUtils;

    @PostMapping("/login")
    public ResponseEntity<?> login(@RequestBody LoginRequest req) {
        Authentication auth = authManager.authenticate(
            new UsernamePasswordAuthenticationToken(req.getEmail(), req.getPassword()));
        String token = jwtUtils.generateToken(req.getEmail());
        return ResponseEntity.ok(Map.of("token", token, "type", "Bearer"));
    }
}

JWT Authentication

Dependency

JWT Utility Class

Auth Controller

Continue learning this concept

JWT Authentication

Dependency

JWT Utility Class

Auth Controller

Continue learning this concept