Feature/AppConfig as PropertySource

pom.xml

@@ -59,11 +59,13 @@
 		<module>spring-cloud-aws-messaging</module>
 		<module>spring-cloud-aws-autoconfigure</module>
 		<module>spring-cloud-aws-parameter-store-config</module>
+		<module>spring-cloud-aws-appconfig</module>
 		<module>spring-cloud-aws-secrets-manager-config</module>
 		<module>spring-cloud-starter-aws</module>
 		<module>spring-cloud-starter-aws-jdbc</module>
 		<module>spring-cloud-starter-aws-messaging</module>
 		<module>spring-cloud-starter-aws-parameter-store-config</module>
+		<module>spring-cloud-starter-aws-appconfig</module>
 		<module>spring-cloud-starter-aws-secrets-manager-config</module>
 		<module>spring-cloud-aws-integration-test</module>
 		<module>docs</module>

spring-cloud-aws-appconfig/pom.xml

@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ 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.
+  -->
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xmlns="http://maven.apache.org/POM/4.0.0"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.cloud</groupId>
+		<artifactId>spring-cloud-aws</artifactId>
+		<version>2.3.0.BUILD-SNAPSHOT</version>
+	</parent>
+
+	<artifactId>spring-cloud-aws-appconfig</artifactId>
+
+	<name>Spring Cloud AWS AppConfig Configuration</name>
+	<description>Spring Cloud AWS AppConfig Configuration</description>
+
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-context</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-autoconfigure</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-context</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>com.amazonaws</groupId>
+			<artifactId>aws-java-sdk-appconfig</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+	</dependencies>
+
+
+</project>

spring-cloud-aws-appconfig/src/main/java/org/springframework/cloud/aws/appconfig/AwsAppConfigPropertySource.java

@@ -0,0 +1,162 @@
+/*
+ * 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.appconfig;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Properties;
+import java.util.Set;
+
+import com.amazonaws.services.appconfig.AmazonAppConfig;
+import com.amazonaws.services.appconfig.model.GetConfigurationRequest;
+import com.amazonaws.services.appconfig.model.GetConfigurationResult;
+import com.fasterxml.jackson.core.type.TypeReference;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import org.springframework.beans.factory.config.YamlPropertiesFactoryBean;
+import org.springframework.core.env.EnumerablePropertySource;
+import org.springframework.core.io.ByteArrayResource;
+import org.springframework.util.ReflectionUtils;
+
+/**
+ * @author jarpz
+ */
+public class AwsAppConfigPropertySource
+		extends EnumerablePropertySource<AmazonAppConfig> {
+
+	private static final String SUPPORTED_TYPE_JSON = "application/json";
+
+	private static final String SUPPORTED_TYPE_YAML = "application/x-yaml";
+
+	private final String accountId;
+
+	private final String application;
+
+	private final String configurationVersion;
+
+	private final String environment;
+
+	private Properties properties;
+
+	public AwsAppConfigPropertySource(String name, String accountId, String application,
+			String environment, String configurationVersion,
+			AmazonAppConfig appConfigClient) {
+		super(name, appConfigClient);
+		this.accountId = accountId;
+		this.application = application;
+		this.configurationVersion = configurationVersion;
+		this.environment = environment;
+	}
+
+	public void init() {
+		GetConfigurationRequest request = new GetConfigurationRequest()
+				.withClientId(accountId).withApplication(application)
+				.withConfiguration(name)
+				.withClientConfigurationVersion(configurationVersion)
+				.withEnvironment(environment);
+
+		getAppConfig(request);
+	}
+
+	@Override
+	public String[] getPropertyNames() {
+		Set<String> strings = properties.stringPropertyNames();
+		return strings.toArray(new String[strings.size()]);
+	}
+
+	@Override
+	public Object getProperty(String name) {
+		return properties.get(name);
+	}
+
+	private void getAppConfig(GetConfigurationRequest request) {
+		GetConfigurationResult result = this.source.getConfiguration(request);
+
+		logger.trace(String.format("loading file: %s/%s/%s/%s", application, name,
+				environment, result.getConfigurationVersion()));
+
+		switch (result.getContentType()) {
+		case SUPPORTED_TYPE_YAML:
+			processYamlContent(result.getContent());
+			break;
+		case SUPPORTED_TYPE_JSON:
+			processJsonContent(result.getContent());
+			break;
+		default:
+			throw new IllegalStateException(String.format("Unsupported content type: %s",
+					result.getContentType()));
+		}
+	}
+
+	private void processYamlContent(ByteBuffer byteBuffer) {
+		YamlPropertiesFactoryBean bean = new YamlPropertiesFactoryBean();
+
+		bean.setResources(new ByteArrayResource(byteBuffer.array()));
+
+		properties = bean.getObject();
+	}
+
+	private void processJsonContent(ByteBuffer byteBuffer) {
+		try {
+			Map<String, Object> map = new ObjectMapper().readValue(byteBuffer.array(),
+					new TypeReference<Map<String, Object>>() {
+					});
+
+			Map<String, Object> result = new LinkedHashMap<>();
+			this.flatten(null, result, map);
+
+			properties = new Properties();
+			properties.putAll(result);
+		}
+		catch (IOException ex) {
+			ReflectionUtils.rethrowRuntimeException(ex);
+		}
+	}
+
+	/**
+	 * flatten json structure.
+	 */
+	private void flatten(String prefix, Map<String, Object> result,
+			Map<String, Object> map) {
+		String namePrefix = Objects.nonNull(prefix) ? prefix + "." : "";
+
+		map.forEach((key, value) -> this.extract(namePrefix + key, result, value));
+	}
+
+	private void extract(String name, Map<String, Object> result, Object value) {
+		if (value instanceof Map) {
+			this.flatten(name, result, (Map) value);
+		}
+		else if (value instanceof Collection) {
+			int index = 0;
+
+			for (Iterator it = ((Collection) value).iterator(); it.hasNext(); ++index) {
+				Object object = it.next();
+				this.extract(name + "[" + index + "]", result, object);
+			}
+		}
+		else {
+			result.put(name, value);
+		}
+	}
+
+}

spring-cloud-aws-appconfig/src/main/java/org/springframework/cloud/aws/appconfig/AwsAppConfigPropertySourceLocator.java

@@ -0,0 +1,110 @@
+/*
+ * 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.appconfig;
+
+import com.amazonaws.services.appconfig.AmazonAppConfig;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+import org.springframework.cloud.bootstrap.config.PropertySourceLocator;
+import org.springframework.core.env.CompositePropertySource;
+import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.Environment;
+import org.springframework.core.env.PropertySource;
+import org.springframework.util.ReflectionUtils;
+
+import static java.util.Objects.isNull;
+import static java.util.Objects.requireNonNull;
+
+/**
+ * @author jarpz
+ */
+public class AwsAppConfigPropertySourceLocator implements PropertySourceLocator {
+
+	private final AmazonAppConfig appConfigClient;
+
+	private final String accountId;
+
+	private final String application;
+
+	private final String configurationProfile;
+
+	private final String environment;
+
+	private final String configurationVersion;
+
+	private final boolean failFast;
+
+	private static final Log logger = LogFactory
+			.getLog(AwsAppConfigPropertySourceLocator.class);
+
+	public AwsAppConfigPropertySourceLocator(AmazonAppConfig appConfigClient,
+			String accountId, String application, String configurationProfile,
+			String environment, String configurationVersion, boolean failFast) {
+		this.appConfigClient = appConfigClient;
+		this.accountId = accountId;
+		this.application = application;
+		this.configurationProfile = configurationProfile;
+		this.environment = environment;
+		this.configurationVersion = configurationVersion;
+		this.failFast = failFast;
+	}
+
+	@Override
+	public PropertySource<?> locate(Environment environment) {
+		if (!(environment instanceof ConfigurableEnvironment)) {
+			return null;
+		}
+
+		ConfigurableEnvironment env = (ConfigurableEnvironment) environment;
+
+		String appName = configurationProfile;
+		if (isNull(appName)) {
+			appName = requireNonNull(env.getProperty("spring.application.name"),
+					"configurationProfile should not be empty or null.");
+		}
+
+		CompositePropertySource composite = new CompositePropertySource("aws-app-config");
+
+		try {
+			composite.addPropertySource(create(appName));
+		}
+		catch (Exception ex) {
+			if (failFast) {
+				logger.error(
+						"Fail fast is set and there was an error reading configuration from AWS AppConfig: {}",
+						ex);
+				ReflectionUtils.rethrowRuntimeException(ex);
+			}
+			else {
+				logger.warn("Unable to load AWS AppConfig from " + appName, ex);
+			}
+		}
+
+		return composite;
+	}
+
+	private AwsAppConfigPropertySource create(String appName) {
+		AwsAppConfigPropertySource propertySource = new AwsAppConfigPropertySource(
+				appName, accountId, application, environment, configurationVersion,
+				appConfigClient);
+		propertySource.init();
+
+		return propertySource;
+	}
+
+}