CloudProfileApplicationListener.java

/*
 * Copyright 2011-2017 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.cloudfoundry.reconfiguration.spring;

import org.cloudfoundry.reconfiguration.util.CloudUtils;
import org.cloudfoundry.reconfiguration.util.StandardCloudUtils;
import org.springframework.boot.context.event.ApplicationEnvironmentPreparedEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.core.Ordered;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.Environment;

import java.util.logging.Logger;

/**
 * A String Boot {@link ApplicationListener} that applies the {@code cloud} profile
 */
public final class CloudProfileApplicationListener implements ApplicationListener<ApplicationEnvironmentPreparedEvent>,
        Ordered {

    private static final String CLOUD_PROFILE = "cloud";

    private static final int OFFSET = 3;

    private static final int ORDER = Ordered.HIGHEST_PRECEDENCE + OFFSET;

    private final Logger logger = Logger.getLogger(this.getClass().getName());

    private final CloudUtils cloudUtils;

    /**
     * Creates a new instance
     */
    public CloudProfileApplicationListener() {
        this(new StandardCloudUtils());
    }

    CloudProfileApplicationListener(CloudUtils cloudUtils) {
        this.cloudUtils = cloudUtils;
    }

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

    @Override
    public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
        ConfigurableEnvironment environment = event.getEnvironment();
        addCloudProfile(environment);
    }

    void addCloudProfile(ConfigurableEnvironment environment) {
        if (this.cloudUtils.isInCloud()) {
            if (hasCloudProfile(environment)) {
                this.logger.fine("'cloud' already in list of active profiles");
            } else {
                this.logger.info("Adding 'cloud' to list of active profiles");
                environment.addActiveProfile(CLOUD_PROFILE);
            }
        } else {
            this.logger.warning("Not running in a cloud. Skipping 'cloud' profile activation.");
        }
    }

    private boolean hasCloudProfile(Environment environment) {
        for (String activeProfile : environment.getActiveProfiles()) {
            if (CLOUD_PROFILE.equalsIgnoreCase(activeProfile)) {
                return true;
            }
        }

        return false;
    }
}