feat: Add JwtAuthenticationFilter (#3)

server-toy-project/src/main/java/com/gdsc_teamb/servertoyproject/jwt/JwtAuthenticationFilter.java

@@ -0,0 +1,45 @@
+package com.gdsc_teamb.servertoyproject.jwt;
+
+import jakarta.servlet.FilterChain;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.ServletRequest;
+import jakarta.servlet.ServletResponse;
+import jakarta.servlet.http.HttpServletRequest;
+import lombok.RequiredArgsConstructor;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.util.StringUtils;
+import org.springframework.web.filter.GenericFilterBean;
+import java.io.IOException;
+
+
+@RequiredArgsConstructor
+public class JwtAuthenticationFilter extends GenericFilterBean {
+
+    private final JwtTokenProvider jwtTokenProvider;
+
+    @Override
+    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
+
+        // Request Header 에서 JWT 토큰 추출
+        String token = resolveToken((HttpServletRequest) request);
+
+        // validateToken 으로 토큰 유효성 검사
+        if (token != null && jwtTokenProvider.validateToken(token)) {
+            // 토큰이 유효할 경우 토큰에서 Authentication 객체를 가지고 와서 SecurityContext에 저장
+            Authentication authentication = jwtTokenProvider.getAuthentication(token);
+            // SecurityContextHolder에 인증 토큰 정보 세팅
+            SecurityContextHolder.getContext().setAuthentication(authentication);
+        }
+        chain.doFilter(request, response);
+    }
+
+    // Request Header 에서 JWT 엑세스 토큰 정보 추출
+    private String resolveToken(HttpServletRequest request) {
+        String bearerToken = request.getHeader("Authorization");
+        if (StringUtils.hasText(bearerToken) && bearerToken.startsWith("Bearer")) {
+            return bearerToken.substring(7);
+        }
+        return null;
+    }
+}