components/camel-aws/src/main/java/org/apache/camel/component/aws/sns/SnsEndpoint.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.camel.component.aws.sns;

import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.services.sns.AmazonSNSClient;
import com.amazonaws.services.sns.model.CreateTopicRequest;
import com.amazonaws.services.sns.model.CreateTopicResult;
import com.amazonaws.services.sns.model.SetTopicAttributesRequest;

import org.apache.camel.CamelContext;
import org.apache.camel.Consumer;
import org.apache.camel.Processor;
import org.apache.camel.Producer;
import org.apache.camel.impl.DefaultEndpoint;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Defines the <a href="http://camel.apache.org/aws.html">AWS SNS Endpoint</a>.  
 *
 */
public class SnsEndpoint extends DefaultEndpoint {

    private static final Logger LOG = LoggerFactory.getLogger(SnsEndpoint.class);

    private SnsConfiguration configuration;
    private AmazonSNSClient snsClient;
    
    public SnsEndpoint(String uri, CamelContext context, SnsConfiguration configuration) {
        super(uri, context);
        this.configuration = configuration;
    }

    public Consumer createConsumer(Processor processor) throws Exception {
        throw new UnsupportedOperationException("You cannot receive messages from this endpoint");
    }

    public Producer createProducer() throws Exception {
        return new SnsProducer(this);
    }

    public boolean isSingleton() {
        return true;
    }

    @Override
    public void doStart() throws Exception {
        super.doStart();
        
        // creates a new topic, or returns the URL of an existing one
        CreateTopicRequest request = new CreateTopicRequest(configuration.getTopicName());
        
        LOG.trace("Creating topic [{}] with request [{}]...", configuration.getTopicName(), request);
        
        CreateTopicResult result = getSNSClient().createTopic(request);
        configuration.setTopicArn(result.getTopicArn());
        
        LOG.trace("Topic created with Amazon resource name: {}", configuration.getTopicArn());
        
        if (configuration.getPolicy() != null) {
            LOG.trace("Updating topic [{}] with policy [{}]", configuration.getTopicArn(), configuration.getPolicy());
            
            getSNSClient().setTopicAttributes(new SetTopicAttributesRequest(configuration.getTopicArn(), "Policy", configuration.getPolicy()));
            
            LOG.trace("Topic policy updated");
        }
    }

    public SnsConfiguration getConfiguration() {
        return configuration;
    }

    public void setConfiguration(SnsConfiguration configuration) {
        this.configuration = configuration;
    }
    
    public void setSNSClient(AmazonSNSClient snsClient) {
        this.snsClient = snsClient;
    }
    
    public AmazonSNSClient getSNSClient() {
        if (snsClient == null) {
            snsClient = configuration.getAmazonSNSClient() != null
                ? configuration.getAmazonSNSClient() : createSNSClient();
        }
        
        return snsClient;
    }

    /**
     * Provide the possibility to override this method for an mock implementation
     *
     * @return AmazonSNSClient
     */
    AmazonSNSClient createSNSClient() {
        AWSCredentials credentials = new BasicAWSCredentials(configuration.getAccessKey(), configuration.getSecretKey());
        AmazonSNSClient client = new AmazonSNSClient(credentials);
        if (configuration.getAmazonSNSEndpoint() != null) {
            client.setEndpoint(configuration.getAmazonSNSEndpoint());
        }
        return client;
    }
}