com.gravitant.cloud.adapters.provision.providers.VolumeDetached.java Source code

Introduction

Here is the source code for com.gravitant.cloud.adapters.provision.providers.VolumeDetached.java

Source

package com.gravitant.cloud.adapters.provision.providers;

/**
 * Licensed to jclouds, Inc. (jclouds) under one or more
 * contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  jclouds 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.
 */

import javax.annotation.Resource;
import javax.inject.Singleton;

import org.jclouds.ec2.domain.Attachment;
import org.jclouds.ec2.domain.Volume;
import org.jclouds.ec2.services.ElasticBlockStoreClient;
import org.jclouds.logging.Logger;

import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;
import com.google.common.collect.Sets;
import com.google.inject.Inject;

/**
 * 
 * Tests to see if a volume is detached.
 * 
 * @author Karthik Arunachalam
 */
@Singleton
public class VolumeDetached implements Predicate<Attachment> {

    private final ElasticBlockStoreClient client;
    @Resource
    protected Logger logger = Logger.NULL;

    @Inject
    public VolumeDetached(ElasticBlockStoreClient client) {
        this.client = client;
    }

    public boolean apply(Attachment attachment) {
        logger.trace("looking for volume %s", attachment.getVolumeId());
        Volume volume = Iterables
                .getOnlyElement(client.describeVolumesInRegion(attachment.getRegion(), attachment.getVolumeId()));

        /*If attachment size is 0 volume is detached for sure.*/
        if (volume.getAttachments().size() == 0) {
            return true;
        }

        /* But if attachment size is > 0, then the attachment could be in any state. 
         * So we need to check if the status is DETACHED (return true) or not (return false). 
         */
        Attachment lastAttachment = Sets.newTreeSet(volume.getAttachments()).last();
        logger.trace("%s: looking for status %s: currently: %s", lastAttachment, Attachment.Status.DETACHED,
                lastAttachment.getStatus());
        return lastAttachment.getStatus() == Attachment.Status.DETACHED;
    }
}