Add aws-parameterstore: prefix config import (#750)

In `spring-boot` 2.4, `Volume Mounted Config Directory Trees` was
added. This commit introduces the prefix `aws-parameterstore:` which
will resolve the values given the configuration properties supported
by parameter store integration. Also, if keys are added after the
prefix then just these will be resolved.

Use: `aws-parameterstore:` or `aws-secretsmanager:my-config-key` or
`aws-parameterstore:my-config-key;my-anoter-config-key`

Closes gh-654

Co-authored-by: Eddú Meléndez <[email protected]>

Author: maciejwalkowiak

docs/src/main/asciidoc/parameter-store.adoc

@@ -93,6 +93,22 @@ logging.level.org.springframework.cloud.aws.paramstore.AwsParamStorePropertySour
 ----
 ====
 
+In `spring-cloud` `2020.0.0` (aka Ilford), the bootstrap phase is no longer enabled by default. In order
+enable it you need an additional dependency:
+
+[source,xml,indent=0]
+----
+<dependency>
+  <groupId>org.springframework.cloud</groupId>
+  <artifactId>spring-cloud-starter-bootstrap</artifactId>
+  <version>{spring-cloud-version}</version>
+</dependency>
+----
+
+However, starting at `spring-cloud-aws` `2.3`, allows import default aws' parameterstore keys
+(`spring.config.import=aws-parameterstore:`) or individual keys
+(`spring.config.import=aws-parameterstore:config-key;other-config-key`)
+
 === IAM Permissions
 Following IAM permissions are required by Spring Cloud AWS:
 

spring-cloud-aws-parameter-store-config/src/main/java/org/springframework/cloud/aws/paramstore/AwsParamStorePropertySource.java

@@ -34,15 +34,16 @@
  * from the AWS Parameter Store using the provided SSM client.
  *
  * @author Joris Kuipers
+ * @author Eddú Meléndez
  * @since 2.0.0
  */
 public class AwsParamStorePropertySource extends EnumerablePropertySource<AWSSimpleSystemsManagement> {
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(AwsParamStorePropertySource.class);
 
-	private String context;
+	private final String context;
 
-	private Map<String, Object> properties = new LinkedHashMap<>();
+	private final Map<String, Object> properties = new LinkedHashMap<>();
 
 	public AwsParamStorePropertySource(String context, AWSSimpleSystemsManagement ssmClient) {
 		super(context, ssmClient);
@@ -57,21 +58,21 @@ public void init() {
 
 	@Override
 	public String[] getPropertyNames() {
-		Set<String> strings = properties.keySet();
+		Set<String> strings = this.properties.keySet();
 		return strings.toArray(new String[strings.size()]);
 	}
 
 	@Override
 	public Object getProperty(String name) {
-		return properties.get(name);
+		return this.properties.get(name);
 	}
 
 	private void getParameters(GetParametersByPathRequest paramsRequest) {
-		GetParametersByPathResult paramsResult = source.getParametersByPath(paramsRequest);
+		GetParametersByPathResult paramsResult = this.source.getParametersByPath(paramsRequest);
 		for (Parameter parameter : paramsResult.getParameters()) {
-			String key = parameter.getName().replace(context, "").replace('/', '.');
+			String key = parameter.getName().replace(this.context, "").replace('/', '.');
 			LOGGER.debug("Populating property retrieved from AWS Parameter Store: {}", key);
-			properties.put(key, parameter.getValue());
+			this.properties.put(key, parameter.getValue());
 		}
 		if (paramsResult.getNextToken() != null) {
 			getParameters(paramsRequest.withNextToken(paramsResult.getNextToken()));

spring-cloud-aws-parameter-store-config/src/main/java/org/springframework/cloud/aws/paramstore/AwsParamStorePropertySourceLocator.java

@@ -31,7 +31,6 @@
 import org.springframework.core.env.ConfigurableEnvironment;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.PropertySource;
-import org.springframework.util.ReflectionUtils;
 
 /**
  * Builds a {@link CompositePropertySource} with various
@@ -43,6 +42,7 @@
  *
  * @author Joris Kuipers
  * @author Matej Nedic
+ * @author Eddú Meléndez
  * @since 2.0.0
  */
 public class AwsParamStorePropertySourceLocator implements PropertySourceLocator {
@@ -73,56 +73,22 @@ public PropertySource<?> locate(Environment environment) {
 
 		ConfigurableEnvironment env = (ConfigurableEnvironment) environment;
 
-		String appName = properties.getName();
-
-		if (appName == null) {
-			appName = env.getProperty("spring.application.name");
-		}
+		AwsParamStorePropertySources sources = new AwsParamStorePropertySources(this.properties, this.logger);
 
 		List<String> profiles = Arrays.asList(env.getActiveProfiles());
-
-		String prefix = this.properties.getPrefix();
-
-		String appContext = prefix + "/" + appName;
-		addProfiles(this.contexts, appContext, profiles);
-		this.contexts.add(appContext + "/");
-
-		String defaultContext = prefix + "/" + this.properties.getDefaultContext();
-		addProfiles(this.contexts, defaultContext, profiles);
-		this.contexts.add(defaultContext + "/");
+		this.contexts.addAll(sources.getAutomaticContexts(profiles));
 
 		CompositePropertySource composite = new CompositePropertySource("aws-param-store");
 
 		for (String propertySourceContext : this.contexts) {
-			try {
-				composite.addPropertySource(create(propertySourceContext));
-			}
-			catch (Exception e) {
-				if (this.properties.isFailFast()) {
-					logger.error(
-							"Fail fast is set and there was an error reading configuration from AWS Parameter Store:\n"
-									+ e.getMessage());
-					ReflectionUtils.rethrowRuntimeException(e);
-				}
-				else {
-					logger.warn("Unable to load AWS config from " + propertySourceContext, e);
-				}
+			PropertySource<AWSSimpleSystemsManagement> propertySource = sources
+					.createPropertySource(propertySourceContext, !this.properties.isFailFast(), this.ssmClient);
+			if (propertySource != null) {
+				composite.addPropertySource(propertySource);
 			}
 		}
 
 		return composite;
 	}
 
-	private AwsParamStorePropertySource create(String context) {
-		AwsParamStorePropertySource propertySource = new AwsParamStorePropertySource(context, this.ssmClient);
-		propertySource.init();
-		return propertySource;
-	}
-
-	private void addProfiles(Set<String> contexts, String baseContext, List<String> profiles) {
-		for (String profile : profiles) {
-			contexts.add(baseContext + this.properties.getProfileSeparator() + profile + "/");
-		}
-	}
-
 }

spring-cloud-aws-parameter-store-config/src/main/java/org/springframework/cloud/aws/paramstore/AwsParamStorePropertySources.java

@@ -0,0 +1,108 @@
+/*
+ * 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.paramstore;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.amazonaws.services.simplesystemsmanagement.AWSSimpleSystemsManagement;
+import org.apache.commons.logging.Log;
+
+import org.springframework.util.StringUtils;
+
+/**
+ * @author Eddú Meléndez
+ * @since 2.3
+ */
+public class AwsParamStorePropertySources {
+
+	private final AwsParamStoreProperties properties;
+
+	private final Log log;
+
+	public AwsParamStorePropertySources(AwsParamStoreProperties properties, Log log) {
+		this.properties = properties;
+		this.log = log;
+	}
+
+	public List<String> getAutomaticContexts(List<String> profiles) {
+		List<String> contexts = new ArrayList<>();
+		String prefix = this.properties.getPrefix();
+		String defaultContext = getContext(prefix, this.properties.getDefaultContext());
+
+		String appName = this.properties.getName();
+
+		String appContext = prefix + "/" + appName;
+		addProfiles(contexts, appContext, profiles);
+		contexts.add(appContext + "/");
+
+		addProfiles(contexts, defaultContext, profiles);
+		contexts.add(defaultContext + "/");
+		return contexts;
+	}
+
+	protected String getContext(String prefix, String context) {
+		if (StringUtils.hasLength(prefix)) {
+			return prefix + "/" + context;
+		}
+		return context;
+	}
+
+	private void addProfiles(List<String> contexts, String baseContext, List<String> profiles) {
+		for (String profile : profiles) {
+			contexts.add(baseContext + this.properties.getProfileSeparator() + profile + "/");
+		}
+	}
+
+	/**
+	 * Creates property source for given context.
+	 * @param context property source context equivalent to the parameter name
+	 * @param optional if creating context should fail with exception if parameter cannot
+	 * be loaded
+	 * @param client System Manager Management client
+	 * @return a property source or null if parameter could not be loaded and optional is
+	 * set to true
+	 */
+	public AwsParamStorePropertySource createPropertySource(String context, boolean optional,
+			AWSSimpleSystemsManagement client) {
+		log.info("Loading property from AWS Parameter Store with name: " + context + ", optional: " + optional);
+		try {
+			AwsParamStorePropertySource propertySource = new AwsParamStorePropertySource(context, client);
+			propertySource.init();
+			return propertySource;
+			// TODO: howto call close when /refresh
+		}
+		catch (Exception e) {
+			if (!optional) {
+				throw new AwsParameterPropertySourceNotFoundException(e);
+			}
+			else {
+				log.warn("Unable to load AWS parameter from " + context + ". " + e.getMessage());
+			}
+		}
+		return null;
+	}
+
+	static class AwsParameterPropertySourceNotFoundException extends RuntimeException {
+
+		AwsParameterPropertySourceNotFoundException(Exception source) {
+			super(source);
+		}
+
+	}
+
+}