omega/omega-transport/omega-transport-resttemplate/src/main/java/org/apache/servicecomb/pack/omega/transport/resttemplate/TransactionHandlerInterceptor.java

/*
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *
 */

package org.apache.servicecomb.pack.omega.transport.resttemplate;

import static org.apache.servicecomb.pack.omega.context.OmegaContext.GLOBAL_TX_ID_KEY;
import static org.apache.servicecomb.pack.omega.context.OmegaContext.LOCAL_TX_ID_KEY;

import java.lang.invoke.MethodHandles;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.servicecomb.pack.omega.context.OmegaContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

class TransactionHandlerInterceptor implements HandlerInterceptor {

  private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());

  private final OmegaContext omegaContext;

  TransactionHandlerInterceptor(OmegaContext omegaContext) {
    this.omegaContext = omegaContext;
  }

  @Override
  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
    if (omegaContext != null) {
      String globalTxId = request.getHeader(GLOBAL_TX_ID_KEY);
      if (globalTxId == null) {
        LOG.debug("Cannot inject transaction ID, no such header: {}", GLOBAL_TX_ID_KEY);
      } else {
        omegaContext.setGlobalTxId(globalTxId);
        omegaContext.setLocalTxId(request.getHeader(LOCAL_TX_ID_KEY));
      }
    } else {
      LOG.debug("Cannot inject transaction ID, as the OmegaContext is null.");
    }
    return true;
  }

  @Override
  public void postHandle(HttpServletRequest request, HttpServletResponse response, Object o, ModelAndView mv) {
  }

  @Override
  public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object o, Exception e) {
    if (omegaContext != null) {
      omegaContext.clear();
    }
  }
}