EventSinkDeployer.java

/*
 * Copyright (c) 2014, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 *
 * 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.wso2.carbon.event.sink;

import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.impl.builder.StAXOMBuilder;
import org.apache.axis2.context.ConfigurationContext;
import org.apache.axis2.deployment.AbstractDeployer;
import org.apache.axis2.deployment.DeploymentException;
import org.apache.axis2.deployment.repository.util.DeploymentFileData;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.wso2.carbon.event.sink.internal.EventSinkStore;

import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import java.io.*;

/**
 * Axis2 deployer which deploys event sinks
 */
public class EventSinkDeployer extends AbstractDeployer {

	private static final Log log = LogFactory.getLog(EventSinkDeployer.class);

	@Override
	public void init(ConfigurationContext configurationContext) {
	}

	/**
	 * Deploys event sink specified by deploymentFileData. This is called whenever an event sink artifact
	 * is added, modified, deleted from the event sink artifact directory
	 *
	 * @param deploymentFileData File data about the event sink artifact to be deployed
	 * @throws DeploymentException
	 */
	@Override
	public void deploy(DeploymentFileData deploymentFileData) throws DeploymentException {

		BufferedInputStream inputStream = null;
		try {
			inputStream = new BufferedInputStream(new FileInputStream(new File(deploymentFileData.getAbsolutePath())));
			XMLStreamReader reader = XMLInputFactory.newInstance().createXMLStreamReader(inputStream);
			StAXOMBuilder builder = new StAXOMBuilder(reader);
			OMElement eventSink = builder.getDocumentElement();

			String eventSinkName = FilenameUtils.getBaseName(deploymentFileData.getFile().getName());
			EventSinkStore.getInstance().addEventSink(EventSink.createEventSink(eventSink, eventSinkName));
			log.info("Deploying event sink: " + eventSinkName + " - file: " + deploymentFileData.getAbsolutePath());
		} catch (FileNotFoundException e) {
			throw new DeploymentException(
					"Deployment artifact file \"" + deploymentFileData.getAbsolutePath() + "\" not found", e);
		} catch (XMLStreamException e) {
			throw new DeploymentException(
					"Event sink XML in \"" + deploymentFileData.getAbsolutePath() + "\" is malformed", e);
		} catch (EventSinkException e) {
			throw new DeploymentException(
					"Event sink configuration in \"" + deploymentFileData.getAbsolutePath() + "\" is invalid", e);
		} finally {
			if (inputStream != null) {
				try {
					inputStream.close();
				} catch (IOException e) {
					log.warn("Failed to close file input stream after deploying event sink from file "
					         + deploymentFileData.getAbsolutePath());
				}
			}
		}
	}

	@Override
	public void setDirectory(String s) {
	}

	@Override
	public void setExtension(String s) {
	}

	/**
	 * Undeploys previously deployed event sink artifact. This is called whenever an event sink artifact is deleted
	 * from event sink artifact directory. Also, this is called when an already existing artifact is modified, followed
	 * by a call to deploy()
	 *
	 * @param fileName File name of the artifact to be undeployed
	 * @throws DeploymentException
	 */
	@Override
	public void undeploy(String fileName) throws DeploymentException {
		String eventSinkName = FilenameUtils.getBaseName(fileName);
		try {
			EventSink.stopDataPublisher(EventSinkStore.getInstance().getEventSink(eventSinkName));
		} catch (EventSinkException e) {
			throw new DeploymentException("Error un-deploying event sink " + eventSinkName, e);
		}
		EventSinkStore.getInstance().removeEventSink(eventSinkName);
		log.info("Event sink named '" + eventSinkName + "' has been undeployed");
	}

	@Override
	public void cleanup() throws DeploymentException {
	}
}