AmazonRdsDataSourceUserTagsFactoryBean.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.jdbc.rds;

import com.amazonaws.regions.Region;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.identitymanagement.AmazonIdentityManagement;
import com.amazonaws.services.rds.AmazonRDS;
import com.amazonaws.services.rds.model.ListTagsForResourceRequest;
import com.amazonaws.services.rds.model.ListTagsForResourceResult;
import com.amazonaws.services.rds.model.Tag;
import org.springframework.beans.factory.config.AbstractFactoryBean;
import org.springframework.cloud.aws.core.env.ResourceIdResolver;
import org.springframework.cloud.aws.core.naming.AmazonResourceName;

import java.util.LinkedHashMap;
import java.util.Map;

/**
 * @author Agim Emruli
 */
public class AmazonRdsDataSourceUserTagsFactoryBean extends AbstractFactoryBean<Map<String, String>> {

    private final AmazonRDS amazonRds;
    private final String dbInstanceIdentifier;
    private final AmazonIdentityManagement identityManagement;

    private ResourceIdResolver resourceIdResolver;
    private Region region;

    public AmazonRdsDataSourceUserTagsFactoryBean(AmazonRDS amazonRds, String dbInstanceIdentifier, AmazonIdentityManagement identityManagement) {
        this.amazonRds = amazonRds;
        this.dbInstanceIdentifier = dbInstanceIdentifier;
        this.identityManagement = identityManagement;
    }

    @Override
    public Class<?> getObjectType() {
        return Map.class;
    }

    @Override
    protected Map<String, String> createInstance() throws Exception {
        LinkedHashMap<String, String> userTags = new LinkedHashMap<>();
        ListTagsForResourceResult tagsForResource = this.amazonRds.listTagsForResource(new ListTagsForResourceRequest().withResourceName(getDbInstanceResourceName()));
        for (Tag tag : tagsForResource.getTagList()) {
            userTags.put(tag.getKey(), tag.getValue());
        }
        return userTags;
    }

    public void setResourceIdResolver(ResourceIdResolver resourceIdResolver) {
        this.resourceIdResolver = resourceIdResolver;
    }

    private String getDbInstanceIdentifier() {
        return this.resourceIdResolver != null ? this.resourceIdResolver.resolveToPhysicalResourceId(this.dbInstanceIdentifier) : this.dbInstanceIdentifier;
    }

    private Region getRegion() {
        if (this.region != null) {
            return this.region;
        }
        return Region.getRegion(Regions.DEFAULT_REGION);
    }

    public void setRegion(Region region) {
        this.region = region;
    }

    /**
     * Unfortunately Amazon AWS mandates to use ARN notation to get the tags. Therefore we first need to get the account
     * number through the IAM service and then construct the ARN out of the account no and region
     *
     * @return the arn string used to query the tags
     */
    private String getDbInstanceResourceName() {
        String userArn = this.identityManagement.getUser().getUser().getArn();
        AmazonResourceName userResourceName = AmazonResourceName.fromString(userArn);
        AmazonResourceName dbResourceArn = new AmazonResourceName.Builder().
                withService("rds").
                withRegion(getRegion()).
                withAccount(userResourceName.getAccount()).
                withResourceType("db").
                withResourceName(getDbInstanceIdentifier()).
                withResourceTypeDelimiter(":").
                build();
        return dbResourceArn.toString();
    }
}