content: /*
   * 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.camel.component.google.mail.stream.transform;
  
  import java.util.Map;
  
  import org.apache.camel.Message;
  import org.apache.camel.cloudevents.CloudEvent;
  import org.apache.camel.cloudevents.CloudEvents;
  import org.apache.camel.component.google.mail.stream.GoogleMailStreamConstants;
  import org.apache.camel.spi.DataType;
  import org.apache.camel.spi.DataTypeTransformer;
  import org.apache.camel.spi.Transformer;
  
  /**
   * Data type transformer converts Google Mail Stream consumer response to CloudEvent v1_0 data format. The data type
   * sets Camel specific CloudEvent headers with values extracted from Google Mail Stream consumer response.
   */
  @DataTypeTransformer(name = "google-mail-stream:application-cloudevents",
                       description = "Adds CloudEvent headers to the Camel message with Google Mail Stream consumer response details")
  public class GoogleMailStreamCloudEventDataTypeTransformer extends Transformer {
  
      @Override
      public void transform(Message message, DataType fromType, DataType toType) {
          final Map<String, Object> headers = message.getHeaders();
  
          CloudEvent cloudEvent = CloudEvents.v1_0;
          headers.putIfAbsent(CloudEvent.CAMEL_CLOUD_EVENT_ID, message.getExchange().getExchangeId());
          headers.putIfAbsent(CloudEvent.CAMEL_CLOUD_EVENT_VERSION, cloudEvent.version());
          headers.put(CloudEvent.CAMEL_CLOUD_EVENT_TYPE, "org.apache.camel.event.google.mail.stream.consume");
  
          if (message.getHeaders().containsKey(GoogleMailStreamConstants.MAIL_FROM)) {
              headers.put(CloudEvent.CAMEL_CLOUD_EVENT_SOURCE,
                      "google.mail.stream." + message.getHeader(GoogleMailStreamConstants.MAIL_FROM, String.class));
          }
  
          headers.put(CloudEvent.CAMEL_CLOUD_EVENT_SUBJECT,
                  message.getHeader(GoogleMailStreamConstants.MAIL_SUBJECT, String.class));
          headers.put(CloudEvent.CAMEL_CLOUD_EVENT_TIME, cloudEvent.getEventTime(message.getExchange()));
          headers.put(CloudEvent.CAMEL_CLOUD_EVENT_CONTENT_TYPE, CloudEvent.APPLICATION_OCTET_STREAM_MIME_TYPE);
      }
  }
  