Java tutorial
/* * Copyright (C) 2016 to the original 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 * * http://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 io.fabric8.spring.cloud.kubernetes.config; import java.io.ByteArrayInputStream; import java.io.IOException; import java.util.HashMap; import java.util.Map; import java.util.Properties; import java.util.function.Function; import java.util.stream.Collectors; import io.fabric8.kubernetes.api.model.ConfigMap; import io.fabric8.kubernetes.client.KubernetesClient; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.config.YamlPropertiesFactoryBean; import org.springframework.core.env.MapPropertySource; import org.springframework.core.io.ByteArrayResource; public class ConfigMapPropertySource extends MapPropertySource { private static final Logger LOGGER = LoggerFactory.getLogger(ConfigMapPropertySource.class); private static final String APPLICATION_YML = "application.yml"; private static final String APPLICATION_YAML = "application.yaml"; private static final String APPLICATION_PROPERTIES = "application.properties"; private static final String PREFIX = "configmap"; public ConfigMapPropertySource(KubernetesClient client, String name) { this(client, name, null); } public ConfigMapPropertySource(KubernetesClient client, String name, String namespace) { super(getName(client, name, namespace), asObjectMap(getData(client, name, namespace))); } private static String getName(KubernetesClient client, String name, String namespace) { return new StringBuilder().append(PREFIX).append(Constants.PROPERTY_SOURCE_NAME_SEPARATOR).append(name) .append(Constants.PROPERTY_SOURCE_NAME_SEPARATOR) .append(namespace == null || namespace.isEmpty() ? client.getNamespace() : namespace).toString(); } private static Map<String, String> getData(KubernetesClient client, String name, String namespace) { Map<String, String> result = new HashMap<>(); try { ConfigMap map = namespace == null || namespace.isEmpty() ? client.configMaps().withName(name).get() : client.configMaps().inNamespace(namespace).withName(name).get(); if (map != null) { for (Map.Entry<String, String> entry : map.getData().entrySet()) { String key = entry.getKey(); String value = entry.getValue(); if (key.equals(APPLICATION_YAML) || key.equals(APPLICATION_YML)) { result.putAll(YAML_TO_PROPETIES.andThen(PROPERTIES_TO_MAP).apply(value)); } else if (key.equals(APPLICATION_PROPERTIES)) { result.putAll(KEY_VALUE_TO_PROPERTIES.andThen(PROPERTIES_TO_MAP).apply(value)); } else { result.put(key, value); } } } } catch (Exception e) { LOGGER.warn( "Can't read configMap with name: [" + name + "] in namespace:[" + namespace + "]. Ignoring"); } return result; } private static Map<String, Object> asObjectMap(Map<String, String> source) { return source.entrySet().stream().collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)); } private static final Function<String, Properties> YAML_TO_PROPETIES = s -> { YamlPropertiesFactoryBean yamlFactory = new YamlPropertiesFactoryBean(); yamlFactory.setResources(new ByteArrayResource(s.getBytes())); return yamlFactory.getObject(); }; private static final Function<String, Properties> KEY_VALUE_TO_PROPERTIES = s -> { Properties properties = new Properties(); try { properties.load(new ByteArrayInputStream(s.getBytes())); return properties; } catch (IOException e) { throw new IllegalArgumentException(); } }; private static final Function<Properties, Map<String, String>> PROPERTIES_TO_MAP = p -> p.entrySet().stream() .collect(Collectors.toMap(e -> String.valueOf(e.getKey()), e -> String.valueOf(e.getValue()))); }