org.apache.servicecomb.config.ConfigurationSpringInitializer.java Source code

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Here is the source code for org.apache.servicecomb.config.ConfigurationSpringInitializer.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.servicecomb.config;

import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;

import org.apache.commons.configuration.AbstractConfiguration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;
import org.springframework.context.EnvironmentAware;
import org.springframework.core.Ordered;
import org.springframework.core.env.CompositePropertySource;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.EnumerablePropertySource;
import org.springframework.core.env.Environment;
import org.springframework.core.env.PropertySource;
import org.springframework.util.StringUtils;

import com.netflix.config.ConfigurationManager;
import com.netflix.config.DynamicPropertyFactory;

public class ConfigurationSpringInitializer extends PropertyPlaceholderConfigurer implements EnvironmentAware {
    private static final Logger LOGGER = LoggerFactory.getLogger(ConfigurationSpringInitializer.class);

    public static final String EXTRA_CONFIG_SOURCE_PREFIX = "extraConfig-";

    public ConfigurationSpringInitializer() {
        setOrder(Ordered.LOWEST_PRECEDENCE / 2);
        setIgnoreUnresolvablePlaceholders(true);
    }

    /**
     * Get configurations from Spring, merge them into the configurations of ServiceComb.
     * @param environment From which to get the extra config.
     */
    @Override
    public void setEnvironment(Environment environment) {
        String environmentName = generateNameForEnvironment(environment);
        LOGGER.info("Environment received, will get configurations from [{}].", environmentName);

        Map<String, Object> extraConfig = getAllProperties(environment);

        ConfigUtil.addExtraConfig(EXTRA_CONFIG_SOURCE_PREFIX + environmentName, extraConfig);

        ConfigUtil.installDynamicConfig();
    }

    @Override
    protected Properties mergeProperties() throws IOException {
        Properties properties = super.mergeProperties();

        AbstractConfiguration config = ConfigurationManager.getConfigInstance();
        Iterator<String> iter = config.getKeys();
        while (iter.hasNext()) {
            String key = iter.next();
            Object value = config.getProperty(key);
            properties.put(key, value);
        }
        return properties;
    }

    @Override
    protected String resolvePlaceholder(String placeholder, Properties props) {
        String propertyValue = super.resolvePlaceholder(placeholder, props);
        if (propertyValue == null) {
            return DynamicPropertyFactory.getInstance().getStringProperty(placeholder, null).get();
        }
        return propertyValue;
    }

    /**
     * Try to get a name for identifying the environment.
     * @param environment the target that the name is generated for.
     * @return The generated name for the environment.
     */
    private String generateNameForEnvironment(Environment environment) {
        String environmentName = environment.getProperty("spring.config.name");
        if (!StringUtils.isEmpty(environmentName)) {
            return environmentName;
        }

        environmentName = environment.getProperty("spring.application.name");
        if (!StringUtils.isEmpty(environmentName)) {
            return environmentName;
        }

        return environment.getClass().getName() + "@" + environment.hashCode();
    }

    /**
     * Traversal all {@link PropertySource} of {@link ConfigurableEnvironment}, and try to get all properties.
     */
    private Map<String, Object> getAllProperties(Environment environment) {
        Map<String, Object> configFromSpringBoot = new HashMap<>();

        if (!(environment instanceof ConfigurableEnvironment)) {
            return configFromSpringBoot;
        }

        ConfigurableEnvironment configurableEnvironment = (ConfigurableEnvironment) environment;
        for (PropertySource<?> propertySource : configurableEnvironment.getPropertySources()) {
            getProperties(configurableEnvironment, propertySource, configFromSpringBoot);
        }
        return configFromSpringBoot;
    }

    /**
     * Get property names from {@link EnumerablePropertySource}, and get property value from {@link ConfigurableEnvironment#getProperty(String)}
     */
    private void getProperties(ConfigurableEnvironment environment, PropertySource<?> propertySource,
            Map<String, Object> configFromSpringBoot) {
        if (propertySource instanceof CompositePropertySource) {
            // recursively get EnumerablePropertySource
            CompositePropertySource compositePropertySource = (CompositePropertySource) propertySource;
            compositePropertySource.getPropertySources()
                    .forEach(ps -> getProperties(environment, ps, configFromSpringBoot));
            return;
        }
        if (propertySource instanceof EnumerablePropertySource) {
            EnumerablePropertySource<?> enumerablePropertySource = (EnumerablePropertySource<?>) propertySource;
            for (String propertyName : enumerablePropertySource.getPropertyNames()) {
                configFromSpringBoot.put(propertyName, environment.getProperty(propertyName));
            }
            return;
        }

        LOGGER.debug("a none EnumerablePropertySource is ignored, propertySourceName = [{}]",
                propertySource.getName());
    }
}