bpel-rest-extensions/src/main/java/org/apache/ode/bpel/extension/bpel4restlight/Bpel4RestLightOperation.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.ode.bpel.extension.bpel4restlight;

import org.apache.ode.bpel.common.FaultException;
import org.apache.ode.bpel.eapi.ExtensionContext;
import org.apache.ode.bpel.eapi.ExtensionOperation;
import org.apache.ode.bpel.extension.bpel4restlight.http.HighLevelRestApi;
import org.apache.ode.bpel.extension.bpel4restlight.http.HttpMethod;
import org.apache.ode.bpel.extension.bpel4restlight.http.HttpResponseMessage;
import org.w3c.dom.Element;

/**
 * 
 * This class provides the implementation of the four typical REST operations
 * GET, PUT, POST and DELETE through corresponding BPEL extension activities
 * ({@link Bpel4RestLightExtensionBundle}).
 * 
 * @author Michael Hahn (mhahn.dev@gmail.com)
 * 
 */
public class Bpel4RestLightOperation implements ExtensionOperation {

	public void run(ExtensionContext context, Element element) throws FaultException {
		String httpMethod = element.getLocalName();

		// Extract requestUri
		String requestUri = Bpel4RestLightUtil.getMethodAttributeValue(context, element, MethodAttribute.REQUEST_URI);

		HttpResponseMessage responseMessage = null;

		// Execute corresponding HttpMethod via the HighLevelRestApi
		switch (HttpMethod.valueOf(httpMethod)) {

		case PUT: {
			String requestPayload = Bpel4RestLightUtil.extractRequestPayload(context, element);
			String acceptHeader = Bpel4RestLightUtil.extractAcceptHeader(context, element);
			responseMessage = HighLevelRestApi.Put(requestUri, requestPayload, acceptHeader);
			break;
		}

		case POST: {
			String requestPayload = Bpel4RestLightUtil.extractRequestPayload(context, element);
			String acceptHeader = Bpel4RestLightUtil.extractAcceptHeader(context, element);
			responseMessage = HighLevelRestApi.Post(requestUri, requestPayload, acceptHeader);
			break;
		}

		case GET: {
			String acceptHeader = Bpel4RestLightUtil.extractAcceptHeader(context, element);
			responseMessage = HighLevelRestApi.Get(requestUri, acceptHeader);
			break;
		}

		case DELETE: {
			String acceptHeader = Bpel4RestLightUtil.extractAcceptHeader(context, element);
			responseMessage = HighLevelRestApi.Delete(requestUri, acceptHeader);
			break;
		}
		default:
			break;
		}

		processResponseMessage(responseMessage, context, element);
	}

	private void processResponseMessage(HttpResponseMessage responseMessage, ExtensionContext context, Element element)
			throws FaultException {
		// Write responsePayload to designated variable
		String responsePayloadVariableName = Bpel4RestLightUtil.getMethodAttributeValue(context, element,
				MethodAttribute.RESPONSE_PAYLOAD_VARIABLE);
		String statusCodeVariableName = Bpel4RestLightUtil.getMethodAttributeValue(context, element,
				MethodAttribute.STATUS_CODE_VARIABLE);

		
		if (responsePayloadVariableName != null && !responsePayloadVariableName.isEmpty()) {
			Bpel4RestLightUtil.writeResponsePayload(context, responseMessage.getResponseBody(),
					responsePayloadVariableName);
		}

		if (statusCodeVariableName != null && !statusCodeVariableName.isEmpty()) {
			Bpel4RestLightUtil.writeResponsePayload(context, responseMessage.getStatusCode(), statusCodeVariableName);
		}
	}
}