[chap.17] BasicAuthenticationFilter

http.httpBasic(Customizer.withDefaults());

Authorization: Basic {Base64Encoded(username:password)}

// username: user, password: pass123 인 경우
Authorization: Basic dXNlcjpwYXNzMTIz

public class BasicAuthenticationFilter extends OncePerRequestFilter {
  
}

protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain chain)
  throws IOException, ServletException {

  try {

    // HTTP Authorization 헤더에서 값을 꺼냄
    Authentication authRequest = this.authenticationConverter.convert(request);
    if (authRequest == null) {
      this.logger.trace("Did not process authentication request since failed to find "
        + "username and password in Basic Authorization header");
      chain.doFilter(request, response);
      return;
    }

    // username 값을 가져옴
    String username = authRequest.getName();
    this.logger.trace(LogMessage.format("Found username '%s' in Basic Authorization header", username));

    // Security Context에 해당 username이 이미 존재하는지 확인
    if (authenticationIsRequired(username)) {
      // 인증 진행
      Authentication authResult = this.authenticationManager.authenticate(authRequest);
      // 인증 결과를 Security Context에 저장
      SecurityContext context = this.securityContextHolderStrategy.createEmptyContext();
      context.setAuthentication(authResult);
      this.securityContextHolderStrategy.setContext(context);
      if (this.logger.isDebugEnabled()) {
        this.logger.debug(LogMessage.format("Set SecurityContextHolder to %s", authResult));
      }
      // Remember Me 서비스에 등록
      this.rememberMeServices.loginSuccess(request, response, authResult);
      // Security Context Repository에 저장
      this.securityContextRepository.saveContext(context, request, response);
      // 로그인 성공 핸들러
      onSuccessfulAuthentication(request, response, authResult);
    }
  } catch (AuthenticationException ex) {
    this.securityContextHolderStrategy.clearContext();
    this.logger.debug("Failed to process authentication request", ex);
    this.rememberMeServices.loginFail(request, response);
    onUnsuccessfulAuthentication(request, response, ex);
    if (this.ignoreFailure) {
      chain.doFilter(request, response);
    } else {
      this.authenticationEntryPoint.commence(request, response, ex);
    }
    return;
  }

  chain.doFilter(request, response);
}

try{
  // 인증 로직
  }catch(AuthenticationException ex){
  securityContextHolderStrategy.

clearContext();
    rememberMeServices.

loginFail(request, response);

onUnsuccessfulAuthentication(request, response, ex);
// ... 추가 예외 처리
}