GitVersionControlSystem.java

/*
 * Copyright 2011 Matthias van der Vlies
 *
 *  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 scm;

import java.io.File;

import models.Application;
import play.Play;
import core.ProcessManager;

/**
 * Implementation for a GIT Version Control System
 */
public class GitVersionControlSystem implements VersionControlSystem {

	public static String getFullGitPath() {
		final String path = Play.configuration.getProperty("path.git");
		// return setting from application.conf or assume command is on the instance's path
		return path == null || path.isEmpty() ? "git" : path;
	}
	
	@Override
	public String checkout(final String pid, final String gitUrl) throws Exception {
		final String checkoutPid = "git-clone-" + pid;
		return ProcessManager.executeCommand(checkoutPid, getFullGitPath()
				+ " clone " + gitUrl + " apps/" + pid, new StringBuffer(), false);
	}
	
	/**
	 * Fetch remote changes, must ALWAYS be called after cleanup()
	 */
	@Override
	public String update(final String pid) throws Exception {
		final String checkoutPid = "git-pull-" + pid;
		final StringBuffer output = new StringBuffer();

		try {
			ProcessManager.executeCommand(checkoutPid, getFullGitPath()
					+ " pull origin master --tags", output, new File("apps/" + pid), false);
		}
		catch(Exception e) {
			// Git will print to stderr when pull is already up-to-date or on fast-forward merge
			if(!output.toString().contains("Already up-to-date") && !output.toString().contains("Fast-forward")) {
				throw e;
			}
		}
		
		return output.toString();
	}
	
	@Override
	public String cleanup(final Application application) throws Exception {
		final String cleanupPid = "git-cleanup-" + application.pid;
		final StringBuffer output = new StringBuffer();
		ProcessManager.executeCommand(cleanupPid, getFullGitPath()
				+ " --git-dir=apps/" + application.pid + "/.git --work-tree=apps/" + application.pid
				+ " checkout -- " + (application.subfolder == null ? "" : application.subfolder) + "conf/application.conf", output, false);
		ProcessManager.executeCommand(cleanupPid, getFullGitPath() + " gc",
				output, new File("apps/" + application.pid), false);
		return output.toString(); 
	}
}