org.springframework.cloud.dataflow.server.config.DefaultEnvironmentPostProcessor.java Source code

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Here is the source code for org.springframework.cloud.dataflow.server.config.DefaultEnvironmentPostProcessor.java

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/*
 * Copyright 2015-2016 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.dataflow.server.config;

import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.beans.factory.config.YamlPropertiesFactoryBean;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.env.EnvironmentPostProcessor;
import org.springframework.core.Ordered;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.MapPropertySource;
import org.springframework.core.env.MutablePropertySources;
import org.springframework.core.env.PropertySource;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;

/**
 * Contributes the values from {@code META-INF/dataflow-server-defaults.yml} and
 * {@code dataflow-server.yml} if it exists, before any of Spring Boot's normal
 * configuration contributions apply. This has the effect of supplying overridable
 * defaults to the various Spring Cloud Data Flow Deployer SPI implementations that in
 * turn override the defaults provided by Spring Boot.
 *
 * @author Josh Long
 * @author Janne Valkealahti
 */
public class DefaultEnvironmentPostProcessor implements EnvironmentPostProcessor, Ordered {

    private static Log logger = LogFactory.getLog(DefaultEnvironmentPostProcessor.class);

    private final Resource serverResource = new ClassPathResource("/dataflow-server.yml");

    private final Resource serverDefaultsResource = new ClassPathResource("META-INF/dataflow-server-defaults.yml");

    private static void contributeDefaults(Map<String, Object> defaults, Resource resource) {
        if (resource.exists()) {
            YamlPropertiesFactoryBean yamlPropertiesFactoryBean = new YamlPropertiesFactoryBean();
            yamlPropertiesFactoryBean.setResources(resource);
            yamlPropertiesFactoryBean.afterPropertiesSet();
            Properties p = yamlPropertiesFactoryBean.getObject();
            for (Object k : p.keySet()) {
                String key = k.toString();
                defaults.put(key, p.get(key));
            }
        }
    }

    @Override
    public void postProcessEnvironment(ConfigurableEnvironment environment, SpringApplication application) {
        Map<String, Object> internalDefaults = new HashMap<>();
        Map<String, Object> defaults = new HashMap<>();
        MutablePropertySources existingPropertySources = environment.getPropertySources();

        contributeDefaults(internalDefaults, serverDefaultsResource);
        contributeDefaults(defaults, serverResource);

        String defaultPropertiesKey = "defaultProperties";

        if (!existingPropertySources.contains(defaultPropertiesKey)
                || existingPropertySources.get(defaultPropertiesKey) == null) {
            existingPropertySources.addLast(new MapPropertySource(defaultPropertiesKey, internalDefaults));
            existingPropertySources.addLast(new MapPropertySource(defaultPropertiesKey, defaults));
        } else {
            PropertySource<?> propertySource = existingPropertySources.get(defaultPropertiesKey);
            @SuppressWarnings("unchecked")
            Map<String, Object> mapOfProperties = Map.class.cast(propertySource.getSource());
            for (String k : internalDefaults.keySet()) {
                Set<String> setOfPropertyKeys = mapOfProperties.keySet();
                if (!setOfPropertyKeys.contains(k)) {
                    mapOfProperties.put(k, internalDefaults.get(k));
                    logger.debug(k + '=' + internalDefaults.get(k));
                }
            }
            for (String k : defaults.keySet()) {
                Set<String> setOfPropertyKeys = mapOfProperties.keySet();
                if (!setOfPropertyKeys.contains(k)) {
                    mapOfProperties.put(k, defaults.get(k));
                    logger.debug(k + '=' + defaults.get(k));
                }
            }
        }

    }

    @Override
    public int getOrder() {
        return 0;
    }
}