#18 [feat] jwt 기능 구현

build.gradle

@@ -23,6 +23,11 @@ repositories {
 }
 
 dependencies {
+	//JWT
+	implementation group: 'io.jsonwebtoken', name: 'jjwt-api', version: '0.11.2'
+	implementation group: 'io.jsonwebtoken', name: 'jjwt-impl', version: '0.11.2'
+	implementation group: 'io.jsonwebtoken', name: 'jjwt-jackson', version: '0.11.2'
+
 	// S3 AWS
 	implementation group: 'org.springframework.cloud', name: 'spring-cloud-starter-aws', version: '2.2.6.RELEASE'
 

src/main/java/com/moddy/server/common/exception/enums/ErrorCode.java

@@ -7,6 +7,10 @@
 @Getter
 @AllArgsConstructor
 public enum ErrorCode {
+    // 401
+    TOKEN_TIME_EXPIRED_EXCEPTION(HttpStatus.UNAUTHORIZED, "토큰이 만료되었습니다. 다시 로그인 해주세요."),
+
+    // 500
     /**
      * 405 METHOD_NOT_ALLOWED
      */

src/main/java/com/moddy/server/config/jwt/JwtService.java

@@ -0,0 +1,104 @@
+package com.moddy.server.config.jwt;
+
+import com.moddy.server.common.exception.model.UnAuthorizedException;
+import io.jsonwebtoken.Claims;
+import io.jsonwebtoken.ExpiredJwtException;
+import io.jsonwebtoken.Header;
+import io.jsonwebtoken.Jwts;
+import io.jsonwebtoken.security.Keys;
+import jakarta.annotation.PostConstruct;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Service;
+
+import java.nio.charset.StandardCharsets;
+import java.security.Key;
+import java.util.Base64;
+import java.util.Date;
+
+import static com.moddy.server.common.exception.enums.ErrorCode.TOKEN_TIME_EXPIRED_EXCEPTION;
+
+@Service
+public class JwtService {
+    @Value("${jwt.secret}")
+    private String jwtSecret;
+    private static final String USER_ID = "USER_ID";
+    private static final String ACCESS_TOKEN = "ACCESS_TOKEN";
+    private static final String REFRESH_TOKEN = "REFRESH_TOKEN";
+    public static final long DAYS_IN_MILLISECONDS = 24 * 60 * 60 * 1000L;
+    public static final int ACCESS_TOKEN_EXPIRATION_DAYS = 30;
+    public static final int REFRESH_TOKEN_EXPIRATION_DAYS = 60;
+
+    @PostConstruct
+    protected void init() {
+        jwtSecret = Base64.getEncoder()
+                .encodeToString(jwtSecret.getBytes(StandardCharsets.UTF_8));
+    }
+
+    public String createAccessToken(final String userId) {
+        final Claims claims = getAccessTokenClaims();
+
+        claims.put(USER_ID, userId);
+        return createToken(claims);
+    }
+
+    public String createRefreshToken(final String userId) {
+        final Claims claims = getRefreshTokenClaims();
+
+        claims.put(USER_ID, userId);
+        return createToken(claims);
+    }
+
+    public boolean verifyToken(final String token) {
+        try {
+            final Claims claims = getBody(token);
+            return true;
+        } catch (RuntimeException e) {
+            if (e instanceof ExpiredJwtException) {
+                throw new UnAuthorizedException(TOKEN_TIME_EXPIRED_EXCEPTION);
+            }
+            return false;
+        }
+    }
+
+    public String getUserIdInToken(final String token) {
+        final Claims claims = getBody(token);
+        return (String) claims.get(USER_ID);
+    }
+
+    private String createToken(final Claims claims) {
+        return Jwts.builder()
+                .setHeaderParam(Header.TYPE, Header.JWT_TYPE)
+                .setClaims(claims)
+                .signWith(getSigningKey())
+                .compact();
+    }
+
+    private Claims getRefreshTokenClaims() {
+        final Date now = new Date();
+        return Jwts.claims()
+                .setSubject(REFRESH_TOKEN)
+                .setIssuedAt(now)
+                .setExpiration(new Date(now.getTime() + REFRESH_TOKEN_EXPIRATION_DAYS * DAYS_IN_MILLISECONDS));
+    }
+
+    private Claims getAccessTokenClaims() {
+        final Date now = new Date();
+        return Jwts.claims()
+                .setSubject(ACCESS_TOKEN)
+                .setIssuedAt(now)
+                .setExpiration(new Date(now.getTime() + ACCESS_TOKEN_EXPIRATION_DAYS * DAYS_IN_MILLISECONDS));
+    }
+
+    private Claims getBody(final String token) {
+        return Jwts.parserBuilder()
+                .setSigningKey(getSigningKey())
+                .build()
+                .parseClaimsJws(token)
+                .getBody();
+    }
+
+    private Key getSigningKey() {
+        final byte[] keyBytes = jwtSecret.getBytes(StandardCharsets.UTF_8);
+        return Keys.hmacShaKeyFor(keyBytes);
+    }
+}