Search code examples
javaescapingcommand-line-interfacersyncapache-commons-exec

Java Rsync Escape Spaces


I am trying to run rsync from a jar. When the source path has no spaces it all works fine, but when the source path has a space in it, it fails. I have tried various methods for escaping the spaces, as per the man pages, such as source.replaceAll("\s", "\\ ") or source.replaceAll("\s", "?"), but to no avail.

When I output the command that is run and then run the exact same command from the command line, it all works. I can't see what I am doing wrong

My code is as follows:

RsyncCommandLine class

public class RsyncCommandLine {

    /** Logger */
    private static final Logger logger = LogManager.getLogger(RsyncCommandLine.class);

    private CommandLine commandLine = null;

    public String startRsync(String source, String destination) throws IOException {
        commandLine = createCommandLine(source, destination);

        CommandLineExecutorHelper helper = new CommandLineExecutorHelper();
        CommandLineLogOutputStream outputStream = helper.executeCommandLine(commandLine);
        validateResponse(outputStream);
        return convertLinesToString(outputStream.getLines());
    }

    private void validateResponse(CommandLineLogOutputStream outputStream) throws IOException {
        if (outputStream == null) {
            logger.error("outputStream  is not valid");
            throw new IOException("Unable to use rsync. ");
        } else if (outputStream.getExitCode() != 0) {
            logger.error("Exit code: " + outputStream.getExitCode());
            logger.error("Validate Response failed " + outputStream.getLines());
            String errorMessage = exitCodeToErrorMessage(outputStream.getExitCode());
            throw new IOException("Error with request. " + errorMessage);
        } else if (outputStream.getLines() == null || outputStream.getLines().isEmpty()) {
            logger.error("Rsync result: " + outputStream.getLines());
            String errorMessage = "Unable to rsync. ";

            throw new IOException(errorMessage);

        }
    }

    private String exitCodeToErrorMessage(int exitCode) {
        String errorMessage = null;
        switch (exitCode) {
            case 0: errorMessage="Success."; break;
            case 1: errorMessage="Syntax or usage error."; break;
            case 2: errorMessage="Protocol incompatibility."; break;
            case 3: errorMessage="Errors selecting input/output files, dirs."; break;
            case 4: errorMessage="Requested action not supported: an attempt was made to manipulate 64-bit files on a platform that cannot support them; or an option was specified that is supported by the client and not by the server."; break;
            case 5: errorMessage="Error starting client-server protocol."; break;
            case 6: errorMessage="Daemon unable to append to log-file."; break;
            case 10: errorMessage="Error in socket I/O."; break;
            case 11: errorMessage="Error in file I/O."; break;
            case 12: errorMessage="Error in rsync protocol data stream."; break;
            case 13: errorMessage="Errors with program diagnostics."; break;
            case 14: errorMessage="Error in IPC code."; break;
            case 20: errorMessage="Received SIGUSR1 or SIGINT."; break;
            case 21: errorMessage="Some error returned by waitpid()."; break;
            case 22: errorMessage="Error allocating core memory buffers."; break;
            case 23: errorMessage="Partial transfer due to error."; break;
            case 24: errorMessage="Partial transfer due to vanished source files."; break;
            case 25: errorMessage="The --max-delete limit stopped deletions."; break;
            case 30: errorMessage="Timeout in data send/receive."; break;
            case 35: errorMessage="Timeout waiting for daemon connection."; break;
            default: errorMessage="Unrecognised error code.";
        }
        return errorMessage;
    }


    protected String convertLinesToString(List<String> lines) {
        String result = null;

        if (lines != null && !lines.isEmpty()) {
            StringBuilder builder = new StringBuilder();
            for (String line : lines) {
                builder.append(line).append(" ");
            }
            result = builder.toString().trim();
        }
        return result;
    }

    protected CommandLine createCommandLine(String source, String destination) {
        // rsync -rtvuch <source> <destination>

        commandLine = new CommandLine("rsync");
        commandLine.addArgument("-rtvuch");

        String escapedSource = source.trim().replaceAll("\\s", "\\\\ ");
        String escapedDestination = destination.trim().replaceAll("\\s", "\\\\ ");
        commandLine.addArgument(source);
        commandLine.addArgument(escapedDestination);

        logger.debug("escapedSource " + escapedSource);
        logger.debug("escapedDestination " + escapedDestination);

        return commandLine;
    }

}

CommandLineExecutorHelper class -

public class CommandLineExecutorHelper {

    /** Logger */
    private static final Logger logger = LogManager.getLogger(CommandLineExecutorHelper.class);

    private DefaultExecutor executor = new DefaultExecutor();

    private ExecuteWatchdog watchdog = new ExecuteWatchdog(10000);

    private DefaultExecuteResultHandler resultHandler = new DefaultExecuteResultHandler();


    public CommandLineExecutorHelper() {
        executor.setWatchdog(watchdog);
    }

    public CommandLineLogOutputStream executeCommandLine(CommandLine commandLine) {
        CommandLineLogOutputStream outputStream = new CommandLineLogOutputStream();
        PumpStreamHandler pumpStreamHandler = new PumpStreamHandler(outputStream);
        executor.setStreamHandler(pumpStreamHandler);
        try {
            executor.execute(commandLine, resultHandler);

            resultHandler.waitFor();
            outputStream.setExitCode(resultHandler.getExitValue());
            logger.debug("\n\ncommandLine " + commandLine);
            logger.debug("exit code " + resultHandler.getExitValue());
            logger.debug("output " + outputStream.getLines());
        } catch (InterruptedException e) {
            outputStream.addErrorMessage(e.getMessage());
            logger.error("executeCommandLine " + e.getMessage());
        } catch (ExecuteException e) {
            outputStream.addErrorMessage(e.getMessage());
            logger.error("executeCommandLine " + e.getMessage());
        } catch (IOException e) {
            outputStream.addErrorMessage(e.getMessage());
            logger.error("executeCommandLine " + e.getMessage());
        } finally {
            IOUtils.closeQuietly(outputStream);
        }

        return outputStream;
    }
}

CommnadLineOutputStream class -

public class CommandLineLogOutputStream extends LogOutputStream {
    private int exitCode = -1;

    private final List<String> lines = new LinkedList<>();

    private StringBuilder errorMessages = new StringBuilder();


    /**
     * @return the exitCode
     */
    public int getExitCode() {
        return exitCode;
    }

    /**
     * @param exitCode the exitCode to set
     */
    public void setExitCode(int exitCode) {
        this.exitCode = exitCode;
    }

    /**
     * @return the lines
     */
    public List<String> getLines() {
        return lines;
    }



    /**
     * @return the errorMessages
     */
    public StringBuilder getErrorMessages() {
        return errorMessages;
    }

    /**
     * @param errorMessages the errorMessages to set
     */
    public void setErrorMessages(StringBuilder errorMessages) {
        this.errorMessages = errorMessages;
    }

    public void addErrorMessage(String errorMessage) {
        this.errorMessages.append(errorMessage);
    }


    @Override
    protected void processLine(String line, int logLevel) {
        lines.add(line);
    }

    /* (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder();
        builder.append("CommandLineLogOutputStream [exitCode=").append(exitCode).append(", lines=").append(lines).append(", errorMessages=").append(errorMessages).append("]");
        return builder.toString();
    }

}

So when I run my jar without a space it is successful:

java -jar myjar.jar -source "/var/source"

output command is:

commandLine [rsync, -rtvuch, "/var/source", /var/dest]

When I run the same jar against a path with spaces:

java -jar myjar.jar -source "/var/source with spaces"

I get the following error message:

Exit code: 23
Validate Response failed [building file list ... donersync: link_stat "/Users/karen/"/var/source with spaces"" failed: No such file or directory (2), building file list ... donersync: link_stat "/Users/karen/"/var/source with spaces"" failed: No such file or directory (2), , sent 21 bytes  received 20 bytes  82.00 bytes/sec, total size is 0  speedup is 0.00, rsync error: some files could not be transferred (code 23) at /BuildRoot/Library/Caches/com.apple.xbs/Sources/rsync/rsync-47/rsync/main.c(992) [sender=2.6.9]]
Unable to rsync Error with request. Partial transfer due to error.

The destination path is picked up from a file open dialog.


Solution

  • After various input I decided to use the ProcessBuilder instead. I then got it working using the following code:

    public class RsyncCommandLine {
    
        /** Logger */
        private static final Logger logger = LogManager.getLogger(RsyncCommandLine.class);
    
    
        public String startRsync(String source, String destination) throws IOException {
            List<String> commands = createCommandLine(source, destination);
            List<String> lines = new ArrayList<>();
            Integer exitCode = null;
            try {
                ProcessBuilder processBuilder = new ProcessBuilder(commands).redirectErrorStream(true);
    
                final Process process = processBuilder.start();
    
                BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));
                String line;
                while ((line = bufferedReader.readLine()) != null) {
                    lines.add(line);
                }
                // Allow process to run up to 60 seconds
                process.waitFor(60, TimeUnit.SECONDS);
                // Get exit code from process
                exitCode = process.exitValue();
                //Convert exit code to meaningful statement
                String exitMessage = exitCodeToErrorMessage(exitCode);               
                lines.add(exitMessage);
            } catch (Exception ex) {
                logger.error(ex);
            }
    
            return convertLinesToString(lines);
        }
    
    
        private String exitCodeToErrorMessage(Integer exitCode) {
            String errorMessage = null;
            switch (exitCode) {
            case 0:
                errorMessage = "Success.";
                break;
            case 1:
                errorMessage = "Syntax or usage error.";
                break;
            case 2:
                errorMessage = "Protocol incompatibility.";
                break;
            case 3:
                errorMessage = "Errors selecting input/output files, dirs.";
                break;
            case 4:
                errorMessage = "Requested action not supported: an attempt was made to manipulate 64-bit files on a platform that cannot support them; or an option was specified that is supported by the client and not by the server.";
                break;
            case 5:
                errorMessage = "Error starting client-server protocol.";
                break;
            case 6:
                errorMessage = "Daemon unable to append to log-file.";
                break;
            case 10:
                errorMessage = "Error in socket I/O.";
                break;
            case 11:
                errorMessage = "Error in file I/O.";
                break;
            case 12:
                errorMessage = "Error in rsync protocol data stream.";
                break;
            case 13:
                errorMessage = "Errors with program diagnostics.";
                break;
            case 14:
                errorMessage = "Error in IPC code.";
                break;
            case 20:
                errorMessage = "Received SIGUSR1 or SIGINT.";
                break;
            case 21:
                errorMessage = "Some error returned by waitpid().";
                break;
            case 22:
                errorMessage = "Error allocating core memory buffers.";
                break;
            case 23:
                errorMessage = "Partial transfer due to error.";
                break;
            case 24:
                errorMessage = "Partial transfer due to vanished source files.";
                break;
            case 25:
                errorMessage = "The --max-delete limit stopped deletions.";
                break;
            case 30:
                errorMessage = "Timeout in data send/receive.";
                break;
            case 35:
                errorMessage = "Timeout waiting for daemon connection.";
                break;
            default:
                errorMessage = "Unrecognised error code.";
            }
            return errorMessage;
        }
    
        protected String convertLinesToString(List<String> lines) {
            String result = null;
    
            if (lines != null && !lines.isEmpty()) {
                StringBuilder builder = new StringBuilder();
                for (String line : lines) {
                    builder.append(line).append(" ");
                }
                result = builder.toString().trim();
            }
            return result;
        }
    
        protected List<String> createCommandLine(String source, String destination) {
            // rsync -rtvuch <source> <destination>
            List<String> commands = new ArrayList<>();
    
            commands.add("rsync");
            commands.add("-rtvuch");
    
            String escapedSource = source.trim();
            String escapedDestination = destination.trim();
    
            commands.add(escapedSource);
            commands.add(escapedDestination);
            logger.debug("escapedSource " + escapedSource);
            logger.debug("escapedDestination " + escapedDestination);
    
            return commands;
        }
    
    }