DynamicQueueUrlDestinationResolver.java

/*
 * Copyright 2013-2014 the original author or authors.
 *
 * Licensed 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.springframework.cloud.aws.messaging.support.destination;

import com.amazonaws.services.sqs.AmazonSQS;
import com.amazonaws.services.sqs.model.CreateQueueRequest;
import com.amazonaws.services.sqs.model.CreateQueueResult;
import com.amazonaws.services.sqs.model.GetQueueUrlRequest;
import com.amazonaws.services.sqs.model.GetQueueUrlResult;
import com.amazonaws.services.sqs.model.QueueDoesNotExistException;
import org.springframework.cloud.aws.core.env.ResourceIdResolver;
import org.springframework.messaging.core.DestinationResolutionException;
import org.springframework.messaging.core.DestinationResolver;
import org.springframework.util.Assert;

import java.net.URI;
import java.net.URISyntaxException;

/**
 * @author Agim Emruli
 * @since 1.0
 */
public class DynamicQueueUrlDestinationResolver implements DestinationResolver<String> {

    private final AmazonSQS amazonSqs;
    private final ResourceIdResolver resourceIdResolver;
    private boolean autoCreate;

    public DynamicQueueUrlDestinationResolver(AmazonSQS amazonSqs, ResourceIdResolver resourceIdResolver) {
        Assert.notNull(amazonSqs, "amazonSqs must not be null");

        this.amazonSqs = amazonSqs;
        this.resourceIdResolver = resourceIdResolver;
    }

    public DynamicQueueUrlDestinationResolver(AmazonSQS amazonSqs) {
        this(amazonSqs, null);
    }

    public void setAutoCreate(boolean autoCreate) {
        this.autoCreate = autoCreate;
    }

    @Override
    public String resolveDestination(String name) throws DestinationResolutionException {
        String queueName = name;

        if (this.resourceIdResolver != null) {
            queueName = this.resourceIdResolver.resolveToPhysicalResourceId(name);
        }

        if (isValidQueueUrl(queueName)) {
            return queueName;
        }

        if (this.autoCreate) {
            //Auto-create is fine to be called even if the queue exists.
            CreateQueueResult createQueueResult = this.amazonSqs.createQueue(new CreateQueueRequest(name));
            return createQueueResult.getQueueUrl();
        } else {
            try {
                GetQueueUrlResult getQueueUrlResult = this.amazonSqs.getQueueUrl(new GetQueueUrlRequest(name));
                return getQueueUrlResult.getQueueUrl();
            } catch (QueueDoesNotExistException e) {
                throw new DestinationResolutionException(e.getMessage(), e);
            }
        }
    }

    private static boolean isValidQueueUrl(String name) {
        try {
            URI candidate = new URI(name);
            return ("http".equals(candidate.getScheme()) || "https".equals(candidate.getScheme()));
        } catch (URISyntaxException e) {
            return false;
        }
    }
}