001/*
002 * (C) Copyright 2018 Nuxeo (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Florent Guillaume
018 */
019package org.nuxeo.runtime.aws;
020
021import static org.apache.commons.lang3.StringUtils.defaultString;
022
023import org.nuxeo.runtime.api.Framework;
024
025import com.amazonaws.SdkClientException;
026import com.amazonaws.regions.AwsRegionProvider;
027import com.amazonaws.regions.DefaultAwsRegionProviderChain;
028
029/**
030 * AWS Region Provider that uses Nuxeo configuration, or uses the default AWS chain as a fallback.
031 *
032 * @since 10.3
033 */
034public class NuxeoAWSRegionProvider extends AwsRegionProvider {
035
036    protected static final AwsRegionProvider INSTANCE = new NuxeoAWSRegionProvider();
037
038    protected static final AwsRegionProvider DEFAULT = new DefaultAwsRegionProviderChain();
039
040    protected static final String DEFAULT_REGION = "us-east-1";
041
042    protected final String id;
043
044    /**
045     * Gets a Nuxeo AWS Region Provider for the default configuration.
046     */
047    public static AwsRegionProvider getInstance() {
048        return INSTANCE;
049    }
050
051    /**
052     * Creates a new Nuxeo AWS Region Provider for the default configuration.
053     */
054    public NuxeoAWSRegionProvider() {
055        this(null);
056    }
057
058    /**
059     * Creates a new Nuxeo AWS Region Provider for the given configuration.
060     *
061     * @param id the configuration id, or {@code null} for the default
062     * @since 11.1
063     */
064    public NuxeoAWSRegionProvider(String id) {
065        this.id = id;
066    }
067
068    @Override
069    public String getRegion() {
070        AWSConfigurationService service = Framework.getService(AWSConfigurationService.class);
071        if (service != null) {
072            String region = service.getAWSRegion(id);
073            if (region != null) {
074                return region;
075            }
076        }
077        String region;
078        try {
079            region = DEFAULT.getRegion();
080        } catch (SdkClientException e) {
081            // the DefaultAwsRegionProviderChain throws when there's no provider instead of defaulting to null
082            region = null;
083        }
084        return defaultString(region, DEFAULT_REGION);
085    }
086
087}