org.springframework.cloud.aws.paramstore.AwsParamStorePropertySourceLocator.java Source code

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Here is the source code for org.springframework.cloud.aws.paramstore.AwsParamStorePropertySourceLocator.java

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/*
 * Copyright 2013-2014 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
 *
 *      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.springframework.cloud.aws.paramstore;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

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 com.amazonaws.services.simplesystemsmanagement.AWSSimpleSystemsManagement;

/**
 * Builds a {@link CompositePropertySource} with various {@link AwsParamStorePropertySource} instances based on
 * active profiles, application name and default context permutations.
 * Mostly copied from Spring Cloud Consul's config support, but without the option to have full config files in a
 * param value: with the AWS Parameter Store that wouldn't make sense, given the maximum size limit of 4096 characters
 * for a parameter value.
 *
 * @author Joris Kuipers
 * @since 2.0.0
 */
public class AwsParamStorePropertySourceLocator implements PropertySourceLocator {

    private AWSSimpleSystemsManagement ssmClient;
    private AwsParamStoreProperties properties;
    private List<String> contexts = new ArrayList<>();

    private Log logger = LogFactory.getLog(getClass());

    public AwsParamStorePropertySourceLocator(AWSSimpleSystemsManagement ssmClient,
            AwsParamStoreProperties properties) {
        this.ssmClient = ssmClient;
        this.properties = properties;
    }

    public List<String> getContexts() {
        return contexts;
    }

    @Override
    public PropertySource<?> locate(Environment environment) {
        if (!(environment instanceof ConfigurableEnvironment)) {
            return null;
        }

        ConfigurableEnvironment env = (ConfigurableEnvironment) environment;

        String appName = properties.getName();

        if (appName == null) {
            appName = env.getProperty("spring.application.name");
        }

        List<String> profiles = Arrays.asList(env.getActiveProfiles());

        String prefix = this.properties.getPrefix();

        String defaultContext = prefix + "/" + this.properties.getDefaultContext();
        this.contexts.add(defaultContext + "/");
        addProfiles(this.contexts, defaultContext, profiles);

        String baseContext = prefix + "/" + appName;
        this.contexts.add(baseContext + "/");
        addProfiles(this.contexts, baseContext, profiles);

        Collections.reverse(this.contexts);

        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);
                }
            }
        }

        return composite;
    }

    private AwsParamStorePropertySource create(String context) {
        AwsParamStorePropertySource propertySource = new AwsParamStorePropertySource(context, this.ssmClient);
        propertySource.init();
        return propertySource;
    }

    private void addProfiles(List<String> contexts, String baseContext, List<String> profiles) {
        for (String profile : profiles) {
            contexts.add(baseContext + this.properties.getProfileSeparator() + profile + "/");
        }
    }

}