JwtTokenProvider.java

package com.example.oauth2.util;

import io.jsonwebtoken.*;
import io.jsonwebtoken.io.Decoders;
import io.jsonwebtoken.security.Keys;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import java.security.Key;
import java.util.Date;

@Slf4j
@Component
public class JwtTokenProvider {
    
    private final Key key;
    private final long accessTokenExpireTime;
    private final long refreshTokenExpireTime;
    
    public JwtTokenProvider(@Value("${jwt.secret}") String secretKey,
                           @Value("${jwt.expiration}") long accessTokenExpireTime) {
        byte[] keyBytes = Decoders.BASE64.decode(secretKey);
        this.key = Keys.hmacShaKeyFor(keyBytes);
        this.accessTokenExpireTime = accessTokenExpireTime;
        this.refreshTokenExpireTime = accessTokenExpireTime * 7; // 7일
    }
    
    // Access Token 생성
    public String createAccessToken(String email, String role) {
        Claims claims = Jwts.claims().setSubject(email);
        claims.put("role", role);
        
        Date now = new Date();
        Date expiryDate = new Date(now.getTime() + accessTokenExpireTime);
        
        return Jwts.builder()
                .setClaims(claims)
                .setIssuedAt(now)
                .setExpiration(expiryDate)
                .signWith(key, SignatureAlgorithm.HS256)
                .compact();
    }
    
    // Refresh Token 생성
    public String createRefreshToken(String email) {
        Claims claims = Jwts.claims().setSubject(email);
        
        Date now = new Date();
        Date expiryDate = new Date(now.getTime() + refreshTokenExpireTime);
        
        return Jwts.builder()
                .setClaims(claims)
                .setIssuedAt(now)
                .setExpiration(expiryDate)
                .signWith(key, SignatureAlgorithm.HS256)
                .compact();
    }
    
    // 토큰에서 이메일 추출
    public String getEmailFromToken(String token) {
        return getClaims(token).getSubject();
    }
    
    // 토큰에서 역할 추출
    public String getRoleFromToken(String token) {
        return getClaims(token).get("role", String.class);
    }
    
    // 토큰 유효성 검증
    public boolean validateToken(String token) {
        try {
            getClaims(token);
            return true;
        } catch (JwtException | IllegalArgumentException e) {
            log.error("유효하지 않은 JWT 토큰: {}", e.getMessage());
            return false;
        }
    }
    
    // 토큰 만료 시간 확인
    public boolean isTokenExpired(String token) {
        Date expiration = getClaims(token).getExpiration();
        return expiration.before(new Date());
    }
    
    private Claims getClaims(String token) {
        return Jwts.parserBuilder()
                .setSigningKey(key)
                .build()
                .parseClaimsJws(token)
                .getBody();
    }
}