Subversion Repositories XServices

/*

 *   Copyright 2013 Brian Rosenberger (Brutex Network)

 *

 *   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 net.brutex.svn;

import java.io.BufferedReader;

import java.io.File;

import java.io.IOException;

import java.io.InputStreamReader;

import java.util.ArrayList;

import java.util.Date;

import java.util.List;

import java.util.StringTokenizer;

import net.brutex.svn.SVNCommitInfo.ChangeType;

import org.apache.log4j.Logger;

/** Executes the svnlook utility

 *

 * @author Brian Rosenberger bru(at)brutex.de

 * @since 0.1

 */

public class SVNLookExecutor {

	private Logger logger = Logger.getLogger(SVNLookExecutor.class);

	private final File svnlook;

	private final String repos;

	private String TXN = null;

	private String rev = null;

	/**

	 * Instantiates a new sVN look executor.

	 *

	 * @param svnlook the svnlook

	 * @param repos the repos

	 */

	public SVNLookExecutor(File svnlook, String repos) {

		if(! svnlook.exists() ) throw new IllegalArgumentException( String.format("The svnlook executable at '%s' does not exist.", svnlook.toString()));

		if(! svnlook.isFile() ) throw new IllegalArgumentException( String.format("The svnlook utility at'%s' is not a file.", svnlook.toString()));

		logger.debug(String.format("Instantiating '%s' with svnlook at '%s'.", this.getClass().getCanonicalName(), svnlook.toString()));

		this.svnlook = svnlook;

		logger.debug(String.format("Working against svn repository at '%s'.", repos));

		this.repos = repos;

	}

	/**

	 * Execute svn look.

	 *

	 * @param command the command

	 * @return the string

	 */

	private String executeSVNLook(SVNLookCommand command) {

		StringBuilder sb = new StringBuilder();

		StringBuilder sberr = new StringBuilder();

		//This throws an IllegalArgumentException when neither TXN nor REV is valid

		String[] params;

		try {

			params = getTargetParam();

		} catch (IllegalArgumentException e) {

			logger.error(e.getMessage());

			throw e;

		}

		try {

			List<String> cmdline =  new ArrayList<String>(5);

			cmdline.add(svnlook.toString());

			cmdline.add(command.getValue());

			cmdline.add(params[0]);

			cmdline.add(params[1]);

			cmdline.add(repos);

			ProcessBuilder pf = new ProcessBuilder(cmdline);

			logger.debug(String.format("Executing svnlook with commandline '%s'.", pf.command()));

			Process svnprocess = pf.start();

			BufferedReader stdin = new BufferedReader(new InputStreamReader(svnprocess.getInputStream()));

			BufferedReader stderr = new BufferedReader(new InputStreamReader(svnprocess.getErrorStream()));

			String s;

			 while( (s = stdin.readLine()) != null ) {

				 sb.append(s + '\n');

			 }

			 while( (s = stderr.readLine()) != null ) {

				 sberr.append(s + '\n');

			 }

			 stdin.close(); stderr.close();

		} catch (IOException e) {

			logger.error( String.format( "Error calling the svnlook utility: '%s'", e.getMessage()));

			e.printStackTrace();

		}

		String error = sberr.toString();

		if( error.length()>0 ) {

			error = "Failed to call svnlook. The STDERR was '"+error+"'";

			logger.error(error);

			throw new IllegalArgumentException(error);

		}

		String output = sb.toString().trim();

		logger.debug(String.format("Svnlook output was '%s'", output));

		return output;

	}

	/*

	 * Returns either -t TXN oder -rev REVISION

	 *

	 * @returns

	 */

	private String[] getTargetParam() {

		String[] result = new String[2];

		if( (TXN==null || TXN.length()<=0) && (rev==null || rev.length()<=0) ) throw new IllegalArgumentException("Either TXN or revision must be provided.");

		if( TXN!=null && TXN.length()>0 && rev!=null && rev.length()>0 ) throw new IllegalArgumentException("Both, TXN and revision are given. Don't know what to use.");

		if( TXN!=null && TXN.length()>0) {

			result[0] = "-t";

			result[1] = TXN;

			return result;

		}

		if( rev!=null && rev.length()>0) {

			result[0] = "-r";

			result[1] = rev;

			return result;

		}

		throw new IllegalArgumentException("Either TXN or revision must be provided.");

	}

	public void setTXN(String TXN) {

		if(TXN==null || TXN.length()<=0) throw new IllegalArgumentException("TXN cannot be null or empty.");

		this.TXN = TXN;

	}

	public void setRev(String rev) {

		if(rev==null || rev.length()<=0) throw new IllegalArgumentException("Revision cannot be null or empty.");

		this.rev = rev;

	}

	public SVNCommitInfo getCommitInfo() {

		String author = executeSVNLook(SVNLookCommand.AUTHOR);

		String logmessage = executeSVNLook(SVNLookCommand.LOG);

		String files = executeSVNLook(SVNLookCommand.CHANGED);

		SVNCommitInfo result = new SVNCommitInfo(author,

												new Date(),

												logmessage);

		files += "\n";

		StringTokenizer tokenizer = new StringTokenizer(files, "\n");

		String s;

		while( tokenizer.hasMoreTokens()) {

			s=tokenizer.nextToken();

			logger.debug(String.format("Tokenizing file list. Token '%s'.", s));

			if(s.startsWith("A")) { result.addFileInfo(ChangeType.ADDED, s.substring(1).trim()); continue; }

			if(s.startsWith("D")) { result.addFileInfo(ChangeType.DELETED, s.substring(1).trim()); continue; }

			if(s.startsWith("UU")) { result.addFileInfo(ChangeType.BOTHUPDATE, s.substring(2).trim()); continue; }

			if(s.startsWith("_U")) { result.addFileInfo(ChangeType.METAUPDATE, s.substring(2).trim()); continue; }

			if(s.startsWith("U")) { result.addFileInfo(ChangeType.UPDATED, s.substring(1).trim()); continue; }

		}

		result.setTxn(TXN);

		result.setRev(rev);

		return result;

	}

}