Java tutorial
/* * Copyright 2011-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * 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://aws.amazon.com/apache2.0 * * This file 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 com.amazonaws.auth; import com.amazonaws.SdkClientException; import com.amazonaws.internal.CredentialsEndpointProvider; import com.amazonaws.retry.internal.CredentialsEndpointRetryPolicy; import com.amazonaws.util.CollectionUtils; import java.net.URI; import java.util.Collections; import java.util.Date; import java.util.HashMap; import java.util.HashSet; import java.util.Map; import java.util.Set; /** * <p> * {@link AWSCredentialsProvider} implementation that loads credentials * from an Amazon Elastic Container. * </p> * <p> * By default, the URI path is retrieved from the environment variable * "AWS_CONTAINER_CREDENTIALS_RELATIVE_URI" in the container's environment. * </p> */ public class ContainerCredentialsProvider implements AWSCredentialsProvider { /** Environment variable to get the Amazon ECS credentials resource path. */ static final String ECS_CONTAINER_CREDENTIALS_PATH = "AWS_CONTAINER_CREDENTIALS_RELATIVE_URI"; /** Environment variable to get the full URI for a credentials path */ static final String CONTAINER_CREDENTIALS_FULL_URI = "AWS_CONTAINER_CREDENTIALS_FULL_URI"; static final String CONTAINER_AUTHORIZATION_TOKEN = "AWS_CONTAINER_AUTHORIZATION_TOKEN"; private static final Set<String> ALLOWED_FULL_URI_HOSTS = allowedHosts(); /** Default endpoint to retreive the Amazon ECS Credentials. */ private static final String ECS_CREDENTIALS_ENDPOINT = "http://169.254.170.2"; private final ContainerCredentialsFetcher credentialsFetcher; /** * @deprecated use {@link #ContainerCredentialsProvider(CredentialsEndpointProvider)} */ @Deprecated public ContainerCredentialsProvider() { this(new ECSCredentialsEndpointProvider()); } public ContainerCredentialsProvider(CredentialsEndpointProvider credentialsEndpointProvider) { this.credentialsFetcher = new ContainerCredentialsFetcher(credentialsEndpointProvider); } @Override public AWSCredentials getCredentials() { return credentialsFetcher.getCredentials(); } @Override public void refresh() { credentialsFetcher.refresh(); } public Date getCredentialsExpiration() { return credentialsFetcher.getCredentialsExpiration(); } static class ECSCredentialsEndpointProvider extends CredentialsEndpointProvider { @Override public URI getCredentialsEndpoint() { String path = System.getenv(ECS_CONTAINER_CREDENTIALS_PATH); if (path == null) { throw new SdkClientException( "The environment variable " + ECS_CONTAINER_CREDENTIALS_PATH + " is empty"); } return URI.create(ECS_CREDENTIALS_ENDPOINT + path); } @Override public CredentialsEndpointRetryPolicy getRetryPolicy() { return ContainerCredentialsRetryPolicy.getInstance(); } } /** * A URI resolver that uses environment variable {@value CONTAINER_CREDENTIALS_FULL_URI} as the URI * for the metadata service. * Optionally an authorization token can be provided using the {@value CONTAINER_AUTHORIZATION_TOKEN} environment variable. */ static class FullUriCredentialsEndpointProvider extends CredentialsEndpointProvider { @Override public URI getCredentialsEndpoint() { String fullUri = System.getenv(CONTAINER_CREDENTIALS_FULL_URI); if (fullUri == null || fullUri.length() == 0) { throw new SdkClientException( "The environment variable " + CONTAINER_CREDENTIALS_FULL_URI + " is empty"); } URI uri = URI.create(fullUri); if (!ALLOWED_FULL_URI_HOSTS.contains(uri.getHost())) { throw new SdkClientException("The full URI (" + uri + ") contained withing environment variable " + CONTAINER_CREDENTIALS_FULL_URI + " has an invalid host. Host can only be one of [" + CollectionUtils.join(ALLOWED_FULL_URI_HOSTS, ", ") + "]"); } return uri; } @Override public Map<String, String> getHeaders() { if (System.getenv(CONTAINER_AUTHORIZATION_TOKEN) != null) { return Collections.singletonMap("Authorization", System.getenv(CONTAINER_AUTHORIZATION_TOKEN)); } return new HashMap<String, String>(); } } private static Set<String> allowedHosts() { HashSet<String> hosts = new HashSet<String>(); hosts.add("127.0.0.1"); hosts.add("localhost"); return Collections.unmodifiableSet(hosts); } }