#Spring Boot ロギング入門 - アクセスログ・業務ログを集める

package dev.mikoto2000.springboot.logging.service;

import java.util.HashSet;
import java.util.Set;

import org.springframework.stereotype.Service;

/**
 * UserService
 */
@Service
public class UserService {

  private final Set<String> users = new HashSet<>();

  public void addUser(String name) {
    users.add(name);
  }

  public void removeUser(String name) {
    users.remove(name);
  }

  public Set<String> getUsers() {
    return new HashSet<String>(users);
  }

  public void fireException() {
    throw new RuntimeException("Hello, Exception!!!");
  }
}

package dev.mikoto2000.springboot.logging.controller;

import java.util.Set;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import dev.mikoto2000.springboot.logging.service.UserService;
import lombok.RequiredArgsConstructor;

/**
 * UserController
 */
@RequiredArgsConstructor
@RestController
public class UserController {

  private final UserService service;

  @GetMapping("addUser")
  public void addUser(
      @RequestParam String name
      ) {
    service.addUser(name);
  }

  @GetMapping("removeUser")
  public void removeUser(
      @RequestParam String name
      ) {
    service.removeUser(name);
  }

  @GetMapping("getUsers")
  public Set<String> getUsers() {
    return service.getUsers();
  }

  @GetMapping("fireException")
  public void fireException() {
    service.fireException();
  }
}

package dev.mikoto2000.springboot.logging.filter;

import java.io.IOException;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import org.springframework.web.filter.OncePerRequestFilter;

import jakarta.servlet.FilterChain;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

@Component
@Order(Ordered.LOWEST_PRECEDENCE)
public class AccessLogFilter extends OncePerRequestFilter {

    private static final Logger accessLogger = LoggerFactory.getLogger("ACCESS_LOG");

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

        long start = System.currentTimeMillis();

        // 接続元 IP 取得
        String ip = request.getRemoteAddr();

        // 成功・失敗フラグ
        boolean success = false;

        try {
            chain.doFilter(request, response);
            success = true;
        } finally {

            long time = System.currentTimeMillis() - start;

            accessLogger.info("ip={}, method={}, request_url={}, status={} success={}, time={}ms",
                ip,
                request.getMethod(),
                request.getRequestURI(),
                response.getStatus(),
                success ? "SUCCESS" : "FAIL",
                time);
        }
    }
}

package dev.mikoto2000.springboot.logging.aop;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class LoggingAspect {

  private static final Logger log = LoggerFactory.getLogger(LoggingAspect.class);

  @Around(
    "within(dev.mikoto2000.springboot.logging.controller..*)"
  )
  public Object logMethod(ProceedingJoinPoint pjp) throws Throwable {

    // メソッド情報取得
    String className = pjp.getTarget().getClass().getSimpleName();
    String methodName = pjp.getSignature().getName();

    log.info("START {}#{}", className, methodName);

    // 時間計測開始
    long startTime = System.currentTimeMillis();
    try {

      Object result = pjp.proceed();

      // 時間計測終了
      long endTime = System.currentTimeMillis();

      log.info("END   {}#{}, time={}ms", className, methodName, endTime - startTime);

      return result;

    } catch (Throwable e) {

      // 時間計測終了
      long endTime = System.currentTimeMillis();

      log.error("ERROR {}#{}, time={}", className, methodName, endTime - startTime, e);

      throw e;
    }
  }
}

package dev.mikoto2000.springboot.logging.filter;

import java.io.IOException;
import java.util.UUID;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.slf4j.MDC;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import org.springframework.web.filter.OncePerRequestFilter;

import jakarta.servlet.FilterChain;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

@Component
@Order(Ordered.LOWEST_PRECEDENCE)
public class AccessLogFilter extends OncePerRequestFilter {

    private static final Logger accessLogger = LoggerFactory.getLogger("ACCESS_LOG");

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

        /* 追加ここから */
        // MDC に記録する値を取得
        String user = "dummy"; // Spring Security と連携すると取得できる
        String traceId = UUID.randomUUID().toString();

        // MDC に値をセット
        MDC.put("user", user);
        MDC.put("traceId", traceId);
        /* 追加ここまで */

        long start = System.currentTimeMillis();

        // 接続元 IP 取得
        String ip = request.getRemoteAddr();

        // 成功・失敗フラグ
        boolean success = false;

        try {
            chain.doFilter(request, response);
            success = true;
        } finally {

            long time = System.currentTimeMillis() - start;

            accessLogger.info("ip={}, method={}, request_url={}, status={}, success={}, time={}ms",
                ip,
                request.getMethod(),
                request.getRequestURI(),
                response.getStatus(),
                success ? "SUCCESS" : "FAIL",
                time);

            /* 追加ここから */
            // MDC クリア
            MDC.clear();
            /* 追加ここまで */
        }
    }
}

Authentication auth =
  SecurityContextHolder.getContext().getAuthentication();

if (auth != null && auth.isAuthenticated()) {
  MDC.put("user", auth.getName());
}

package dev.mikoto2000.springboot.logging.service;

import java.util.HashSet;
import java.util.Set;

import org.springframework.stereotype.Service;

import lombok.extern.slf4j.Slf4j;

/**
 * UserService
 */
@Service
@Slf4j
public class UserService {

  private final Set<String> users = new HashSet<>();

  public void addUser(String name) {
    /* 修正ここから */
    if (users.add(name)) {
      log.info("Add user: name={}", name);
    } else {
      log.warn("Add user failed: name={}", name);
    }
    /* 修正ここまで */
  }

  public void removeUser(String name) {
    /* 修正ここから */
    if (users.remove(name)) {
      log.info("Remove user: name={}", name);
    } else {
      log.warn("Remove user failed: name={}", name);
    }
    /* 修正ここまで */
  }

  public Set<String> getUsers() {
    return new HashSet<String>(users);
  }

  public void fireException() {
    throw new RuntimeException("Hello, Exception!!!");
  }
}