Add option to use default AWS region provider chain.

Fixes gh-553
Fixes gh-120
Closes gh-559
Closes gh-560

docs/src/main/asciidoc/_configprops.adoc

@@ -1,18 +1,18 @@
 |===
 |Name | Default | Description
 
-|aws.paramstore.default-context | application | 
+|aws.paramstore.default-context | application |
 |aws.paramstore.enabled | true | Is AWS Parameter Store support enabled.
 |aws.paramstore.fail-fast | true | Throw exceptions during config lookup if true, otherwise, log warnings.
 |aws.paramstore.name |  | Alternative to spring.application.name to use in looking up values in AWS Parameter Store.
 |aws.paramstore.prefix | /config | Prefix indicating first level for every property. Value must start with a forward slash followed by a valid path segment or be empty. Defaults to "/config".
-|aws.paramstore.profile-separator | _ | 
-|aws.secretsmanager.default-context | application | 
+|aws.paramstore.profile-separator | _ |
+|aws.secretsmanager.default-context | application |
 |aws.secretsmanager.enabled | true | Is AWS Secrets Manager support enabled.
 |aws.secretsmanager.fail-fast | true | Throw exceptions during config lookup if true, otherwise, log warnings.
 |aws.secretsmanager.name |  | Alternative to spring.application.name to use in looking up values in AWS Secrets Manager.
 |aws.secretsmanager.prefix | /secret | Prefix indicating first level for every property. Value must start with a forward slash followed by a valid path segment or be empty. Defaults to "/config".
-|aws.secretsmanager.profile-separator | _ | 
+|aws.secretsmanager.profile-separator | _ |
 |cloud.aws.credentials.access-key |  | The access key to be used with a static provider.
 |cloud.aws.credentials.instance-profile | true | Configures an instance profile credentials provider with no further configuration.
 |cloud.aws.credentials.profile-name |  | The AWS profile name.
@@ -23,7 +23,8 @@
 |cloud.aws.loader.max-pool-size |  | The maximum pool size of the Task Executor used for parallel S3 interaction. @see org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor#setMaxPoolSize(int)
 |cloud.aws.loader.queue-capacity |  | The maximum queue capacity for backed up S3 requests. @see org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor#setQueueCapacity(int)
 |cloud.aws.region.auto | true | Enables automatic region detection based on the EC2 meta data service.
-|cloud.aws.region.static |  | 
+|cloud.aws.region.use-default-aws-region-chain | false | Use the DefaultAwsRegion Chain instead of configuring a custom region provider chain.
+|cloud.aws.region.static |  |
 |cloud.aws.stack.auto | true | Enables the automatic stack name detection for the application.
 |cloud.aws.stack.name | myStackName | The name of the manually configured stack name that will be used to retrieve the resources.
 

docs/src/main/asciidoc/spring-cloud-aws.adoc

@@ -315,6 +315,10 @@ The properties to configure the region are shown below
 |true
 |Enables automatic region detection based on the EC2 meta data service
 
+|cloud.aws.region.useDefaultAwsRegionChain
+|true
+|Use the DefaultAWSRegion Chain instead of configuring a custom region chain
+
 |cloud.aws.region.static
 |eu-west-1
 |Configures a static region for the application. Possible regions are (currently) us-east-1, us-west-1, us-west-2,

spring-cloud-aws-autoconfigure/src/main/java/org/springframework/cloud/aws/autoconfigure/context/ContextCredentialsAutoConfiguration.java

@@ -82,9 +82,11 @@ public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata,
 				return;
 			}
 
-			Boolean useDefaultCredentialsChain = this.environment.getProperty(
-					AWS_CREDENTIALS_PROPERTY_PREFIX + ".use-default-aws-credentials-chain",
-					Boolean.class, false);
+			Boolean useDefaultCredentialsChain = this.environment
+					.getProperty(
+							AWS_CREDENTIALS_PROPERTY_PREFIX
+									+ ".use-default-aws-credentials-chain",
+							Boolean.class, false);
 			String accessKey = this.environment
 					.getProperty(AWS_CREDENTIALS_PROPERTY_PREFIX + ".access-key");
 			String secretKey = this.environment
@@ -99,7 +101,7 @@ public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata,
 								AWS_CREDENTIALS_PROPERTY_PREFIX + ".instance-profile",
 								Boolean.class, true)
 								&& !this.environment.containsProperty(
-								AWS_CREDENTIALS_PROPERTY_PREFIX + ".access-key"),
+										AWS_CREDENTIALS_PROPERTY_PREFIX + ".access-key"),
 						this.environment.getProperty(
 								AWS_CREDENTIALS_PROPERTY_PREFIX + ".profile-name",
 								DEFAULT_PROFILE_NAME),

spring-cloud-aws-autoconfigure/src/main/java/org/springframework/cloud/aws/autoconfigure/context/ContextRegionProviderAutoConfiguration.java

@@ -70,12 +70,19 @@ public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata,
 				return;
 			}
 
-			registerRegionProvider(registry, this.environment.getProperty(
+			boolean useDefaultRegionChain = this.environment.getProperty(
+					AWS_REGION_PROPERTIES_PREFIX + ".use-default-aws-region-chain",
+					Boolean.class, false);
+
+			String staticRegion = this.environment
+					.getProperty(AWS_REGION_PROPERTIES_PREFIX + ".static");
+
+			boolean autoDetect = this.environment.getProperty(
 					AWS_REGION_PROPERTIES_PREFIX + ".auto", Boolean.class, true)
-					&& !StringUtils.hasText(this.environment
-							.getProperty(AWS_REGION_PROPERTIES_PREFIX + ".static")),
-					this.environment
-							.getProperty(AWS_REGION_PROPERTIES_PREFIX + ".static"));
+					&& !StringUtils.hasText(staticRegion);
+
+			registerRegionProvider(registry, autoDetect, useDefaultRegionChain,
+					staticRegion);
 		}
 
 		@Override

spring-cloud-aws-autoconfigure/src/main/java/org/springframework/cloud/aws/autoconfigure/context/properties/AwsRegionProperties.java

@@ -20,6 +20,7 @@
  * Properties related to AWS region configuration.
  *
  * @author Tom Gianos
+ * @author Maciej Walkowiak
  * @since 2.0.2
  * @see org.springframework.cloud.aws.autoconfigure.context.ContextRegionProviderAutoConfiguration
  */
@@ -30,6 +31,12 @@ public class AwsRegionProperties {
 	 */
 	private boolean auto = true;
 
+	/**
+	 * Whether default AWS SDK region provider chain should be used when auto is set to
+	 * true.
+	 */
+	private boolean useDefaultAwsRegionChain;
+
 	/**
 	 * Configures a static region for the application. Possible regions are (currently)
 	 * us-east-1, us-west-1, us-west-2, eu-west-1, eu-central-1, ap-southeast-1,
@@ -60,4 +67,12 @@ public void setStatic(String staticRegion) {
 		this.staticRegion = staticRegion;
 	}
 
+	public boolean isUseDefaultAwsRegionChain() {
+		return useDefaultAwsRegionChain;
+	}
+
+	public void setUseDefaultAwsRegionChain(boolean useDefaultAwsRegionChain) {
+		this.useDefaultAwsRegionChain = useDefaultAwsRegionChain;
+	}
+
 }

spring-cloud-aws-autoconfigure/src/test/java/org/springframework/cloud/aws/autoconfigure/context/ContextCredentialsAutoConfigurationTest.java

@@ -148,7 +148,8 @@ public void credentialsProvider_propertyToUseDefaultIsSet_configuresDefaultAwsCr
 	public void credentialsProvider_dashSeparatedPropertyToUseDefaultIsSet_configuresDefaultAwsCredentialsProvider() {
 		this.context = new AnnotationConfigApplicationContext();
 		this.context.register(ContextCredentialsAutoConfiguration.class);
-		TestPropertyValues.of("cloud.aws.credentials.use-default-aws-credentials-chain:true")
+		TestPropertyValues
+				.of("cloud.aws.credentials.use-default-aws-credentials-chain:true")
 				.applyTo(this.context);
 		this.context.refresh();
 

spring-cloud-aws-autoconfigure/src/test/java/org/springframework/cloud/aws/autoconfigure/context/ContextRegionProviderAutoConfigurationTest.java

@@ -21,16 +21,20 @@
 import org.junit.After;
 import org.junit.Test;
 
+import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.boot.test.util.TestPropertyValues;
+import org.springframework.cloud.aws.core.region.DefaultAwsRegionProviderChainDelegate;
 import org.springframework.cloud.aws.core.region.Ec2MetadataRegionProvider;
 import org.springframework.cloud.aws.core.region.StaticRegionProvider;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 /**
  * @author Agim Emruli
  * @author Petromir Dzhunev
+ * @author Maciej Walkowiak
  */
 public class ContextRegionProviderAutoConfigurationTest {
 
@@ -93,4 +97,23 @@ public void regionProvider_staticRegionConfigured_staticRegionProviderWithConfig
 				.isEqualTo(Region.getRegion(Regions.EU_WEST_1));
 	}
 
+	@Test
+	public void regionProvider_autoDetectionAndDefaultChainConfigured_DefaultAwsRegionProviderChainDelegateConfigured() {
+		// Arrange
+		this.context = new AnnotationConfigApplicationContext();
+		this.context.register(ContextRegionProviderAutoConfiguration.class);
+		TestPropertyValues.of("cloud.aws.region.auto:true").applyTo(this.context);
+		TestPropertyValues.of("cloud.aws.region.useDefaultAwsRegionChain:true")
+				.applyTo(this.context);
+
+		// Act
+		this.context.refresh();
+
+		// Assert
+		assertThat(this.context.getBean(DefaultAwsRegionProviderChainDelegate.class))
+				.isNotNull();
+		assertThatThrownBy(() -> this.context.getBean(Ec2MetadataRegionProvider.class))
+				.isInstanceOf(NoSuchBeanDefinitionException.class);
+	}
+
 }

spring-cloud-aws-context/src/main/java/org/springframework/cloud/aws/context/config/annotation/ContextRegionConfigurationRegistrar.java

@@ -43,9 +43,12 @@ public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata,
 						+ importingClassMetadata.getClassName());
 
 		boolean autoDetect = annotationAttributes.getBoolean("autoDetect");
+		boolean useDefaultAwsRegionChain = annotationAttributes
+				.getBoolean("useDefaultAwsRegionChain");
 		String configuredRegion = annotationAttributes.getString("region");
 
-		registerRegionProvider(registry, autoDetect, configuredRegion);
+		registerRegionProvider(registry, autoDetect, useDefaultAwsRegionChain,
+				configuredRegion);
 	}
 
 }

spring-cloud-aws-context/src/main/java/org/springframework/cloud/aws/context/config/annotation/EnableContextRegion.java

@@ -21,6 +21,8 @@
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import com.amazonaws.regions.AwsRegionProviderChain;
+
 import org.springframework.context.annotation.Import;
 
 /**
@@ -29,11 +31,15 @@
  * Service clients that are created inside the application context (by the Spring Cloud
  * AWS classes). A region can be either manually configured
  * {@link EnableContextRegion#region()} with a constant expression, dynamic expression
- * (using a SpEL expression) or a place holder. The region can also be dynamically
- * retrieved from the EC2 instance meta-data if the application context is running inside
- * a EC2 instance by enabling the {@link EnableContextRegion#autoDetect()} attribute.
+ * (using a SpEL expression) or a place holder. If the application context is running
+ * inside a EC2 instance The region can also be dynamically retrieved from the EC2
+ * instance meta-data by enabling the {@link EnableContextRegion#autoDetect()} attribute
+ * or from the default AWS SDK {@link AwsRegionProviderChain} by enabling
+ * {@link EnableContextRegion#autoDetect()} and
+ * {@link EnableContextRegion#useDefaultAwsRegionChain()}.
  *
  * @author Agim Emruli
+ * @author Maciej Walkowiak
  */
 @Retention(RetentionPolicy.RUNTIME)
 @Target(ElementType.TYPE)
@@ -58,4 +64,12 @@
 	 */
 	boolean autoDetect() default false;
 
+	/**
+	 * Whether default AWS SDK region provider chain should be used when auto is set to
+	 * true.
+	 * @return - if default AWS SDK region provider chain should be used for region
+	 * resolution.
+	 */
+	boolean useDefaultAwsRegionChain() default false;
+
 }

spring-cloud-aws-context/src/main/java/org/springframework/cloud/aws/context/config/support/ContextConfigurationUtils.java

@@ -31,6 +31,7 @@
 import org.springframework.beans.factory.support.ManagedList;
 import org.springframework.cloud.aws.core.config.AmazonWebserviceClientConfigurationUtils;
 import org.springframework.cloud.aws.core.credentials.CredentialsProviderFactoryBean;
+import org.springframework.cloud.aws.core.region.DefaultAwsRegionProviderChainDelegate;
 import org.springframework.cloud.aws.core.region.Ec2MetadataRegionProvider;
 import org.springframework.cloud.aws.core.region.StaticRegionProvider;
 import org.springframework.util.StringUtils;
@@ -55,7 +56,7 @@ private ContextConfigurationUtils() {
 	}
 
 	public static void registerRegionProvider(BeanDefinitionRegistry registry,
-			boolean autoDetect, String configuredRegion) {
+			boolean autoDetect, boolean useDefaultRegionChain, String configuredRegion) {
 		if (autoDetect && StringUtils.hasText(configuredRegion)) {
 			throw new IllegalArgumentException(
 					"No region must be configured if autoDetect is defined as true");
@@ -64,8 +65,9 @@ public static void registerRegionProvider(BeanDefinitionRegistry registry,
 		AbstractBeanDefinition beanDefinition;
 
 		if (autoDetect) {
-			beanDefinition = BeanDefinitionBuilder
-					.genericBeanDefinition(Ec2MetadataRegionProvider.class)
+			beanDefinition = BeanDefinitionBuilder.genericBeanDefinition(
+					useDefaultRegionChain ? DefaultAwsRegionProviderChainDelegate.class
+							: Ec2MetadataRegionProvider.class)
 					.getBeanDefinition();
 		}
 		else if (StringUtils.hasText(configuredRegion)) {

spring-cloud-aws-context/src/test/java/org/springframework/cloud/aws/context/config/annotation/ContextRegionConfigurationRegistrarTest.java

@@ -82,6 +82,21 @@ public void regionProvider_withAutoDetectedRegion_dynamicRegionProviderConfigure
 		assertThat(staticRegionProvider).isNotNull();
 	}
 
+	@Test
+	public void regionProvider_withAutoDetectedRegionAndDefaultChain_defaulAwsChainRegionProviderConfigured()
+			throws Exception {
+		// Arrange
+		this.context = new AnnotationConfigApplicationContext(
+				ApplicationConfigurationWithDynamicRegionProvider.class);
+
+		// Act
+		Ec2MetadataRegionProvider staticRegionProvider = this.context
+				.getBean(Ec2MetadataRegionProvider.class);
+
+		// Assert
+		assertThat(staticRegionProvider).isNotNull();
+	}
+
 	@Test
 	public void regionProvider_withExpressionConfiguredRegion_staticRegionProviderConfigured()
 			throws Exception {
@@ -219,4 +234,10 @@ static class ApplicationConfigurationWithWrongRegion {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	@EnableContextRegion(autoDetect = true, useDefaultAwsRegionChain = true)
+	static class ApplicationConfigurationWithAutoDetectionAndDefaultChain {
+
+	}
+
 }

spring-cloud-aws-core/src/main/java/org/springframework/cloud/aws/core/region/DefaultAwsRegionProviderChainDelegate.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2013-2020 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
+ *
+ *      https://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.region;
+
+import com.amazonaws.regions.DefaultAwsRegionProviderChain;
+import com.amazonaws.regions.Region;
+import com.amazonaws.regions.RegionUtils;
+
+/**
+ * {@link RegionProvider} implementation that delegates to
+ * {@link DefaultAwsRegionProviderChain} enabling loading region configuration from
+ * environment variables, system properties, AWS profile, and instance metadata.
+ *
+ * @author Maciej Walkowiak
+ * @since 1.0
+ */
+public class DefaultAwsRegionProviderChainDelegate implements RegionProvider {
+
+	private final DefaultAwsRegionProviderChain delegate = new DefaultAwsRegionProviderChain();
+
+	@Override
+	public Region getRegion() {
+		return RegionUtils.getRegion(delegate.getRegion());
+	}
+
+}

spring-cloud-aws-messaging/src/main/java/org/springframework/cloud/aws/messaging/config/annotation/SnsWebConfiguration.java

@@ -46,4 +46,5 @@ public void addArgumentResolvers(
 			}
 		};
 	}
+
 }