/*
* Copyright 2011-2017 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.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. 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.client.builder;
import com.amazonaws.AmazonWebServiceClient;
import com.amazonaws.ClientConfiguration;
import com.amazonaws.ClientConfigurationFactory;
import com.amazonaws.PredefinedClientConfigurations;
import com.amazonaws.SdkClientException;
import com.amazonaws.annotation.NotThreadSafe;
import com.amazonaws.annotation.SdkInternalApi;
import com.amazonaws.annotation.SdkProtectedApi;
import com.amazonaws.annotation.SdkTestInternalApi;
import com.amazonaws.auth.AWSCredentialsProvider;
import com.amazonaws.auth.DefaultAWSCredentialsProviderChain;
import com.amazonaws.client.AwsAsyncClientParams;
import com.amazonaws.client.AwsSyncClientParams;
import com.amazonaws.handlers.RequestHandler2;
import com.amazonaws.metrics.RequestMetricCollector;
import com.amazonaws.regions.AwsRegionProvider;
import com.amazonaws.regions.DefaultAwsRegionProviderChain;
import com.amazonaws.regions.Region;
import com.amazonaws.regions.RegionUtils;
import com.amazonaws.regions.Regions;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ExecutorService;
/**
* Base class for all service specific client builders.
*
* @param <Subclass> Concrete builder type, used for better fluent methods.
* @param <TypeToBuild> Type that this builder builds.
*/
@NotThreadSafe
@SdkProtectedApi
public abstract class AwsClientBuilder<Subclass extends AwsClientBuilder, TypeToBuild> {
/**
* Default Region Provider chain. Used only when the builder is not explicitly configured with a
* region.
*/
private static final AwsRegionProvider DEFAULT_REGION_PROVIDER = new DefaultAwsRegionProviderChain();
/**
* Different services may have custom client configuration factories to vend defaults tailored
* for that service. If no explicit client configuration is provided to the builder the default
* factory for the service is used.
*/
private final ClientConfigurationFactory clientConfigFactory;
/**
* {@link AwsRegionProvider} to use when no explicit region or endpointConfiguration is configured.
* This is currently not exposed for customization by customers.
*/
private final AwsRegionProvider regionProvider;
private AWSCredentialsProvider credentials;
private ClientConfiguration clientConfig;
private RequestMetricCollector metricsCollector;
private Region region;
private List<RequestHandler2> requestHandlers;
private EndpointConfiguration endpointConfiguration;
protected AwsClientBuilder(ClientConfigurationFactory clientConfigFactory) {
this(clientConfigFactory, DEFAULT_REGION_PROVIDER);
}
@SdkTestInternalApi
protected AwsClientBuilder(ClientConfigurationFactory clientConfigFactory,
AwsRegionProvider regionProvider) {
this.clientConfigFactory = clientConfigFactory;
this.regionProvider = regionProvider;
}
/**
* Gets the AWSCredentialsProvider currently configured in the builder.
*/
public final AWSCredentialsProvider getCredentials() {
return this.credentials;
}
/**
* Sets the AWSCredentialsProvider used by the client. If not specified the default is {@link
* DefaultAWSCredentialsProviderChain}.
*
* @param credentialsProvider New AWSCredentialsProvider to use.
*/
public final void setCredentials(AWSCredentialsProvider credentialsProvider) {
this.credentials = credentialsProvider;
}
/**
* Sets the AWSCredentialsProvider used by the client. If not specified the default is {@link
* DefaultAWSCredentialsProviderChain}.
*
* @param credentialsProvider New AWSCredentialsProvider to use.
* @return This object for method chaining.
*/
public final Subclass withCredentials(AWSCredentialsProvider credentialsProvider) {
setCredentials(credentialsProvider);
return getSubclass();
}
/**
* If the builder isn't explicitly configured with credentials we use the {@link
* DefaultAWSCredentialsProviderChain}.
*/
private AWSCredentialsProvider resolveCredentials() {
return (credentials == null) ? DefaultAWSCredentialsProviderChain.getInstance() : credentials;
}
/**
* Gets the ClientConfiguration currently configured in the builder
*/
public final ClientConfiguration getClientConfiguration() {
return this.clientConfig;
}
/**
* Sets the ClientConfiguration to be used by the client. If not specified the default is
* typically {@link PredefinedClientConfigurations#defaultConfig} but may differ per service.
*
* @param config Custom configuration to use
*/
public final void setClientConfiguration(ClientConfiguration config) {
this.clientConfig = config;
}
/**
* Sets the ClientConfiguration to be used by the client. If not specified the default is
* typically {@link PredefinedClientConfigurations#defaultConfig} but may differ per service.
*
* @param config Custom configuration to use
* @return This object for method chaining.
*/
public final Subclass withClientConfiguration(ClientConfiguration config) {
setClientConfiguration(config);
return getSubclass();
}
/**
* If not explicit client configuration is provided we consult the {@link
* ClientConfigurationFactory} of the service. If an explicit configuration is provided we use
* ClientConfiguration's copy constructor to avoid mutation.
*/
private ClientConfiguration resolveClientConfiguration() {
return (clientConfig == null) ? clientConfigFactory.getConfig() :
new ClientConfiguration(clientConfig);
}
/**
* Gets the {@link RequestMetricCollector} in use by the builder.
*/
public final RequestMetricCollector getMetricsCollector() {
return this.metricsCollector;
}
/**
* Sets a custom RequestMetricCollector to use for the client.
*
* @param metrics Custom RequestMetricCollector to use.
*/
public final void setMetricsCollector(RequestMetricCollector metrics) {
this.metricsCollector = metrics;
}
/**
* Sets a custom RequestMetricCollector to use for the client.
*
* @param metrics Custom RequestMetricCollector to use.
* @return This object for method chaining.
*/
public final Subclass withMetricsCollector(RequestMetricCollector metrics) {
setMetricsCollector(metrics);
return getSubclass();
}
/**
* Gets the region in use by the builder.
*/
public final String getRegion() {
return region == null ? null : region.getName();
}
/**
* Sets the region to be used by the client. This will be used to determine both the
* service endpoint (eg: https://sns.us-west-1.amazonaws.com) and signing region (eg: us-west-1)
* for requests. If neither region or endpoint configuration {@link #setEndpointConfiguration(EndpointConfiguration)}
* are explicitly provided in the builder the {@link #DEFAULT_REGION_PROVIDER} is consulted.
*
* @param region Region to use
*/
public final void setRegion(String region) {
withRegion(region);
}
/**
* Sets the region to be used by the client. This will be used to determine both the
* service endpoint (eg: https://sns.us-west-1.amazonaws.com) and signing region (eg: us-west-1)
* for requests. If neither region or endpoint configuration {@link #setEndpointConfiguration(EndpointConfiguration)}
* are explicitly provided in the builder the {@link #DEFAULT_REGION_PROVIDER} is consulted.
*
* <p> For regions not explicitly in the {@link Regions} enum use the {@link
* #withRegion(String)} overload.</p>
*
* @param region Region to use
* @return This object for method chaining.
*/
public final Subclass withRegion(Regions region) {
return withRegion(region.getName());
}
/**
* Sets the region to be used by the client. This will be used to determine both the
* service endpoint (eg: https://sns.us-west-1.amazonaws.com) and signing region (eg: us-west-1)
* for requests. If neither region or endpoint configuration {@link #setEndpointConfiguration(EndpointConfiguration)}
* are explicitly provided in the builder the {@link #DEFAULT_REGION_PROVIDER} is consulted.
*
* @param region Region to use
* @return This object for method chaining.
*/
public final Subclass withRegion(String region) {
return withRegion(RegionUtils.getRegion(region));
}
/**
* Sets the region to be used by the client. This will be used to determine both the
* service endpoint (eg: https://sns.us-west-1.amazonaws.com) and signing region (eg: us-west-1)
* for requests. If neither region or endpoint configuration {@link #setEndpointConfiguration(EndpointConfiguration)}
* are explicitly provided in the builder the {@link #DEFAULT_REGION_PROVIDER} is consulted.
*
* @param region Region to use, this will be used to determine both service endpoint
* and the signing region
* @return This object for method chaining.
*/
private Subclass withRegion(Region region) {
this.region = region;
return getSubclass();
}
/**
* Gets the service endpointConfiguration in use by the builder
*/
public final EndpointConfiguration getEndpoint() {
return endpointConfiguration;
}
/**
* Sets the endpoint configuration (service endpoint & signing region) to be used for requests. If neither region {@link #setRegion(String)}
* or endpoint configuration are explicitly provided in the builder the {@link #DEFAULT_REGION_PROVIDER} is consulted.
*
* <p><b>Only use this if using a non-standard service endpoint - the recommended approach for configuring a client is to use {@link #setRegion(String)}</b>
*
* @param endpointConfiguration The endpointConfiguration to use
*/
public final void setEndpointConfiguration(EndpointConfiguration endpointConfiguration) {
withEndpointConfiguration(endpointConfiguration);
}
/**
* Sets the endpoint configuration (service endpoint & signing region) to be used for requests. If neither region {@link #withRegion(String)}
* or endpoint configuration are explicitly provided in the builder the {@link #DEFAULT_REGION_PROVIDER} is consulted.
*
* <p><b>Only use this if using a non-standard service endpoint - the recommended approach for configuring a client is to use {@link #withRegion(String)}</b>
*
* @param endpointConfiguration The endpointConfiguration to use
* @return This object for method chaining.
*/
public final Subclass withEndpointConfiguration(EndpointConfiguration endpointConfiguration) {
this.endpointConfiguration = endpointConfiguration;
return getSubclass();
}
/**
* Gets the list of request handlers in use by the builder.
*/
public final List<RequestHandler2> getRequestHandlers() {
return this.requestHandlers == null ? null :
Collections.unmodifiableList(this.requestHandlers);
}
/**
* Sets the request handlers to use in the client.
*
* @param handlers Request handlers to use for client.
*/
public final void setRequestHandlers(RequestHandler2... handlers) {
this.requestHandlers = Arrays.asList(handlers);
}
/**
* Sets the request handlers to use in the client.
*
* @param handlers Request handlers to use for client.
* @return This object for method chaining.
*/
public final Subclass withRequestHandlers(RequestHandler2... handlers) {
setRequestHandlers(handlers);
return getSubclass();
}
/**
* Request handlers are copied to a new list to avoid mutation, if no request handlers are
* provided to the builder we supply an empty list.
*/
private List<RequestHandler2> resolveRequestHandlers() {
return (requestHandlers == null) ? new ArrayList<RequestHandler2>() :
new ArrayList<RequestHandler2>(requestHandlers);
}
/**
* Region and endpoint logic is tightly coupled to the client class right now so it's easier to
* set them after client creation and let the normal logic kick in. Ideally this should resolve
* the endpoint and signer information here and just pass that information as is to the client.
*
* @param clientInterface Client to configure
*/
@SdkInternalApi
final TypeToBuild configureMutableProperties(TypeToBuild clientInterface) {
AmazonWebServiceClient client = (AmazonWebServiceClient) clientInterface;
setRegion(client);
client.makeImmutable();
return clientInterface;
}
/**
* Builds a client with the configure properties.
*
* @return Client instance to make API calls with.
*/
public abstract TypeToBuild build();
/**
* @return An instance of AwsSyncClientParams that has all params to be used in the sync client
* constructor.
*/
protected final AwsSyncClientParams getSyncClientParams() {
return new SyncBuilderParams();
}
private void setRegion(AmazonWebServiceClient client) {
if (region != null && endpointConfiguration != null) {
throw new IllegalStateException("Only one of Region or EndpointConfiguration may be set.");
}
if (endpointConfiguration != null) {
client.setEndpoint(endpointConfiguration.getServiceEndpoint());
client.setSignerRegionOverride(endpointConfiguration.getSigningRegion());
} else if (region != null) {
client.setRegion(region);
} else {
final String region = determineRegionFromRegionProvider();
if (region != null) {
client.setRegion(RegionUtils.getRegion(region));
} else {
throw new SdkClientException(
"Unable to find a region via the region provider chain. " +
"Must provide an explicit region in the builder or setup environment to supply a region.");
}
}
}
/**
* Attempt to determine the region from the configured region provider. This will return null in the event that the
* region provider could not determine the region automatically.
*/
private String determineRegionFromRegionProvider() {
try {
return regionProvider.getRegion();
}
catch (SdkClientException e) {
// The AwsRegionProviderChain that is used by default throws an exception instead of returning null when
// the region is not defined. For that reason, we have to support both throwing an exception and returning
// null as the region not being defined.
return null;
}
}
@SuppressWarnings("unchecked")
protected final Subclass getSubclass() {
return (Subclass) this;
}
/**
* Presents a view of the builder to be used in a client constructor.
*/
protected class SyncBuilderParams extends AwsAsyncClientParams {
private final ClientConfiguration _clientConfig;
private final AWSCredentialsProvider _credentials;
private final RequestMetricCollector _metricsCollector;
private final List<RequestHandler2> _requestHandlers;
protected SyncBuilderParams() {
this._clientConfig = resolveClientConfiguration();
this._credentials = resolveCredentials();
this._metricsCollector = metricsCollector;
this._requestHandlers = resolveRequestHandlers();
}
@Override
public AWSCredentialsProvider getCredentialsProvider() {
return this._credentials;
}
@Override
public ClientConfiguration getClientConfiguration() {
return this._clientConfig;
}
@Override
public RequestMetricCollector getRequestMetricCollector() {
return this._metricsCollector;
}
@Override
public List<RequestHandler2> getRequestHandlers() {
return this._requestHandlers;
}
@Override
public ExecutorService getExecutor() {
throw new UnsupportedOperationException("ExecutorService is not used for sync client.");
}
}
/**
* A container for configuration required to submit requests to a service (service endpoint and signing region)
*/
public static final class EndpointConfiguration {
private final String serviceEndpoint;
private final String signingRegion;
/**
* @param serviceEndpoint the service endpoint either with or without the protocol (e.g. https://sns.us-west-1.amazonaws.com or sns.us-west-1.amazonaws.com)
* @param signingRegion the region to use for SigV4 signing of requests (e.g. us-west-1)
*/
public EndpointConfiguration(String serviceEndpoint, String signingRegion) {
this.serviceEndpoint = serviceEndpoint;
this.signingRegion = signingRegion;
}
public String getServiceEndpoint() {
return serviceEndpoint;
}
public String getSigningRegion() {
return signingRegion;
}
}
}