CredentialsProviderFactoryBean.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.core.credentials;

import com.amazonaws.auth.AWSCredentialsProvider;
import com.amazonaws.auth.AWSCredentialsProviderChain;
import com.amazonaws.auth.DefaultAWSCredentialsProviderChain;
import org.springframework.beans.factory.config.AbstractFactoryBean;
import org.springframework.util.Assert;

import java.util.Collections;
import java.util.List;

/**
 * {@link org.springframework.beans.factory.FactoryBean} that creates a composite {@link AWSCredentialsProvider} based
 * on the delegates.
 *
 * @author Agim Emruli
 * @since 1.0
 */
public class CredentialsProviderFactoryBean extends AbstractFactoryBean<AWSCredentialsProvider> {

    public static final String CREDENTIALS_PROVIDER_BEAN_NAME = "credentialsProvider";

    private final List<AWSCredentialsProvider> delegates;

    public CredentialsProviderFactoryBean() {
        this(Collections.<AWSCredentialsProvider>emptyList());
    }

    public CredentialsProviderFactoryBean(List<AWSCredentialsProvider> delegates) {
        Assert.notNull(delegates, "Delegates must not be null");
        this.delegates = delegates;
    }

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

    @Override
    protected AWSCredentialsProvider createInstance() throws Exception {
        AWSCredentialsProviderChain awsCredentialsProviderChain;
        if (this.delegates.isEmpty()) {
            awsCredentialsProviderChain = new DefaultAWSCredentialsProviderChain();
        } else {
            awsCredentialsProviderChain = new AWSCredentialsProviderChain(this.delegates.toArray(new AWSCredentialsProvider[this.delegates.size()]));
        }

        awsCredentialsProviderChain.setReuseLastProvider(false);
        return awsCredentialsProviderChain;
    }
}