Metadata-Version: 1.0
Name: zdaemon
Version: 2.0.4
Summary: Daemon process control library and tools for Unix-based systems
Home-page: http://www.python.org/pypi/zdaemon
Author: Zope Corporation and Contributors
Author-email: zope-dev@zope.org
License: ZPL 2.1
Description: *****************************************************
        ``zdaemon`` process controller for Unix-based systems
        *****************************************************
        
        `zdaemon` is a Python package which provides APIs for managing applications
        run as daemons.  Its principal use to date has been to manage the application
        server and storage server daemons for Zope / ZEO, although it is not limited
        to running Python-based applications (for instance, it has been used to
        manage the 'spread' daemon).
        
        .. contents::
        
        ===========
        Changelog
        ===========
        
        
        2.0.4 (2009-04-20)
        ==================
        
        - Version 2.0.3 broke support for relative paths to the socket (``-s``
        option and ``socket-name`` parameter), now relative paths work again
        as in version 2.0.2.
        
        - Fixed change log format, made table of contents nicer.
        
        - Fixed author's email address.
        
        - Removed zpkg stuff.
        
        
        2.0.3 (2009-04-11)
        ==================
        
        - Added support to bootstrap on Jython.
        
        - If the run directory does not exist it will be created. This allow to use
        `/var/run/mydaemon` as run directory when /var/run is a tmpfs (LP #318118).
        
        Bugs Fixed
        ----------
        
        - No longer uses a hardcoded filename (/tmp/demo.zdsock) in unit tests.
        This lets you run the tests on Python 2.4 and 2.5 simultaneously without
        spurious errors.
        
        - make -h work again for both runner and control scripts.
        Help is now taken from the __doc__ of the options class users by
        the zdaemon script being run.
        
        2.0.2 (2008-04-05)
        ==================
        
        Bugs Fixed
        ----------
        
        - Fixed backwards incompatible change in handling of environment option.
        
        2.0.1 (2007-10-31)
        ==================
        
        Bugs Fixed
        ----------
        
        - Fixed test renormalizer that did not work in certain cases where the
        environment was complex.
        
        2.0.0 (2007-07-19)
        ==================
        
        - Final release for 2.0.0.
        
        2.0a6 (2007-01-11)
        ==================
        
        Bugs Fixed
        ----------
        
        - When the user option was used, it only affected running the daemon.
        
        2.0a3, 2.0a4, 2.0a5 (2007-01-10)
        ================================
        
        Bugs Fixed
        ----------
        
        - The new (2.0) mechanism used by zdaemon to start the daemon manager
        broke some applications that extended zdaemon.
        
        - Added extra checks to deal with programs that extend zdaemon
        and copy the schema and thus don't see updates to the ZConfig schema.
        
        2.0a2 (2007-01-10)
        ==================
        
        New Features
        ------------
        
        - Added support for setting environment variables in the configuration
        file.  This is useful when zdaemon is used to run programs that need
        environment variables set (e.g. LD_LIBRARY_PATH).
        
        - Added a command to rotate the transcript log.
        
        2.0a1 (2006-12-21)
        ==================
        
        Bugs Fixed
        ----------
        
        - In non-daemon mode, start hung, producing annoying dots
        when the program exited.
        
        - The start command hung producing annoying dots if the deamon failed
        to start.
        
        - foreground and start had different semantics because one used
        os.system and another used os.spawn
        
        New Features
        ------------
        
        - Documentation
        
        - Command-line arguments can now be supplied to the start and
        foreground (fg) commands
        
        - zdctl now invokes itself to run zdrun.  This means that it's
        no-longer necessary to generate a separate zdrun script.  This
        especially when the magic techniques to find and run zdrun using
        directory sniffing fail to set the path corrrectly.
        
        - The daemon mode is now enabled by default.  To get non-deamon mode,
        you have to use a configuration file and set deamon to off
        there. The old -d option is kept for backward compatibility, but is
        a no-op.
        
        1.4a1 (2005-11-21)
        ==================
        
        - Fixed a bug in the distribution setup file.
        
        1.4a1 (2005-11-05)
        ==================
        
        - First semi-formal release.
        
        After some unknown release(???)
        ===============================
        
        - Made 'zdaemon.zdoptions' not fail for --help when __main__.__doc__
        is None.
        
        After 1.1
        =========
        
        - Updated test 'testRunIgnoresParentSignals':
        
        o Use 'mkdtemp' to create a temporary directory to hold the test socket
        rather than creating the test socket in the test directory.
        Hopefully this will be more robust.  Sometimes the test directory
        has a path so long that the test socket can't be created.
        
        o Changed management of 'donothing.sh'.  This script is now created by
        the test in the temporarary directory with the necessary
        permissions. This is to avoids possible mangling of permissions
        leading to spurious test failures.  It also avoids management of a
        file in the source tree, which is a bonus.
        
        - Rearranged source tree to conform to more usual zpkg-based layout:
        
        o Python package lives under 'src'.
        
        o Dependencies added to 'src' as 'svn:externals'.
        
        o Unit tests can now be run from a checkout.
        
        - Made umask-based test failures due to running as root emit a more
        forceful warning.
        
        1.1 (2005-06-09)
        ================
        
        - SVN tag:  svn://svn.zope.org/repos/main/zdaemon/tags/zdaemon-1.1
        
        - Tagged to make better 'svn:externals' linkage possible.
        
        To-Dos
        ======
        
        More docs:
        
        - Document/demonstrate some important features, such as:
        
        - working directory
        
        Bugs:
        
        - help command
        
        ===============
        Using zdaemon
        ===============
        
        zdaemon provides a script, zdaemon, that can be used to running other
        programs as POSIX (Unix) daemons. (Of course, it is only usable on
        POSIX-complient systems.
        
        Using zdaemon requires specifying a number of options, which can be
        given in a configuration file, or as command-line options.  It also
        accepts commands teling it what do do.  The commands are:
        
        start
        Start a process as a daemon
        
        stop
        Stop a running daemon process
        
        restart
        Stop and then restart a program
        
        status
        Find out if the program is running
        
        foreground or fg
        Run a program
        
        kill signal
        Send a signal to the daemon process
        
        reopen_transcript
        Reopen the transcript log.  See the discussion of the transcript
        log below.
        
        help command
        Get help on a command
        
        
        Commands can be given on a command line, or can be given using an
        interactive interpreter.
        
        Let's start with a simple example.  We'll use command-line options to
        run the echo command:
        
        >>> system("./zdaemon -p 'echo hello world' fg")
        echo hello world
        hello world
        
        Here we used the -p option to specify a program to run.  We can
        specify a program name and command-line options in the program
        command. Note, however, that the command-line parsing is pretty
        primitive.  Quotes and spaces aren't handled correctly.  Let's look at
        a slightly more complex example.  We'll run the sleep command as a
        daemon :)
        
        >>> system("./zdaemon -p 'sleep 100' start")
        . .
        daemon process started, pid=819
        
        This ran the sleep deamon.  We can check whether it ran with the
        status command:
        
        >>> system("./zdaemon -p 'sleep 100' status")
        program running; pid=819
        
        We can stop it with the stop command:
        
        >>> system("./zdaemon -p 'sleep 100' stop")
        . .
        daemon process stopped
        
        >>> system("./zdaemon -p 'sleep 100' status")
        daemon manager not running
        
        Normally, we control zdaemon using a configuration file.  Let's create
        a typical configuration file:
        
        >>> open('conf', 'w').write(
        ... '''
        ... <runner>
        ...   program sleep 100
        ... </runner>
        ... ''')
        
        Now, we can run with the -C option to read the configuration file:
        
        >>> system("./zdaemon -Cconf start")
        . .
        daemon process started, pid=1136
        
        If we list the directory:
        
        >>> system("ls")
        conf
        zdaemon
        zdsock
        
        We'll see that a file, zdsock, was created.  This is a unix-domain
        socket used internally by ZDaemon.  We'll normally want to control
        where this goes.
        
        >>> system("./zdaemon -Cconf stop")
        . .
        daemon process stopped
        
        >>> open('conf', 'w').write(
        ... '''
        ... <runner>
        ...   program sleep 100
        ...   socket-name /tmp/demo.zdsock
        ... </runner>
        ... '''.replace('/tmp', tmpdir))
        
        
        >>> system("./zdaemon -Cconf start")
        . .
        daemon process started, pid=1139
        
        >>> system("ls")
        conf
        zdaemon
        
        >>> import os
        >>> os.path.exists("/tmp/demo.zdsock".replace('/tmp', tmpdir))
        True
        
        >>> system("./zdaemon -Cconf stop")
        . .
        daemon process stopped
        
        In the example, we included a command-line argument in the program
        option. We can also provide options on the command line:
        
        >>> open('conf', 'w').write(
        ... '''
        ... <runner>
        ...   program sleep
        ...   socket-name /tmp/demo.zdsock
        ... </runner>
        ... '''.replace('/tmp', tmpdir))
        
        >>> system("./zdaemon -Cconf start 100")
        . .
        daemon process started, pid=1149
        
        >>> system("./zdaemon -Cconf status")
        program running; pid=1149
        
        >>> system("./zdaemon -Cconf stop")
        . .
        daemon process stopped
        
        Environment Variables
        =====================
        
        Sometimes, it is necessary to set environment variables before running
        a program.  Perhaps the most common case for this is setting
        LD_LIBRARY_PATH so that dynamically loaded libraries can be found.
        
        >>> open('conf', 'w').write(
        ... '''
        ... <runner>
        ...   program env
        ...   socket-name /tmp/demo.zdsock
        ... </runner>
        ... <environment>
        ...   LD_LIBRARY_PATH /home/foo/lib
        ...   HOME /home/foo
        ... </environment>
        ... '''.replace('/tmp', tmpdir))
        
        >>> system("./zdaemon -Cconf fg")
        env
        USER=jim
        HOME=/home/foo
        LOGNAME=jim
        USERNAME=jim
        TERM=dumb
        PATH=/home/jim/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin
        EMACS=t
        LANG=en_US.UTF-8
        SHELL=/bin/bash
        EDITOR=emacs
        LD_LIBRARY_PATH=/home/foo/lib
        
        Transcript log
        ==============
        
        When zdaemon run a program in daemon mode, it disconnects the
        program's standard input, standard output, and standard error from the
        controlling terminal.  It can optionally redirect the output to
        standard error and standard output to a file.  This is done with the
        transcript option.  This is, of course, useful for logging output from
        long-running applications.
        
        Let's look at an example. We'll have a long-running process that
        simple tails a data file:
        
        >>> f = open('data', 'w', 0)
        >>> import os
        >>> f.write('rec 1\n'); os.fsync(f.fileno())
        
        >>> open('conf', 'w').write(
        ... '''
        ... <runner>
        ...   program tail -f data
        ...   transcript log
        ... </runner>
        ... ''')
        
        >>> system("./zdaemon -Cconf start")
        . .
        daemon process started, pid=7963
        
        .. Wait a little bit to make sure tail has a chance to work
        
        >>> import time
        >>> time.sleep(0.1)
        
        Now, if we look at the log file, it contains the tail output:
        
        >>> open('log').read()
        'rec 1\n'
        
        We can rotate the transcript log by renaming it and telling zdaemon to
        reopen it:
        
        >>> import os
        >>> os.rename('log', 'log.1')
        
        If we generate more output:
        
        >>> f.write('rec 2\n'); os.fsync(f.fileno())
        
        .. Wait a little bit to make sure tail has a chance to work
        
        >>> time.sleep(1)
        
        The output will appear in the old file, because zdaemon still has it
        open:
        
        >>> open('log.1').read()
        'rec 1\nrec 2\n'
        
        Now, if we tell zdaemon to reopen the file:
        
        >>> system("./zdaemon -Cconf reopen_transcript")
        
        and generate some output:
        
        >>> f.write('rec 3\n'); os.fsync(f.fileno())
        
        .. Wait a little bit to make sure tail has a chance to work
        
        >>> time.sleep(1)
        
        the output will show up in the new file, not the old:
        
        >>> open('log').read()
        'rec 3\n'
        
        >>> open('log.1').read()
        'rec 1\nrec 2\n'
        
        Reference Documentation
        =======================
        
        The following options are available for use in the runner section of
        configuration files and as command-line options.
        
        program
        Command-line option: -p or --program
        
        This option gives the command used to start the subprocess
        managed by zdaemon.  This is currently a simple list of
        whitespace-delimited words. The first word is the program
        file, subsequent words are its command line arguments.  If the
        program file contains no slashes, it is searched using $PATH.
        (Note that there is no way to to include whitespace in the program
        file or an argument, and under certain circumstances other
        shell metacharacters are also a problem.)
        
        socket-name
        Command-line option: -s or --socket-name.
        
        The pathname of the Unix domain socket used for communication
        between the zdaemon command-line tool and a deamon-management
        process.  The default is relative to the current directory in
        which zdaemon is started.  You want to specify
        an absolute pathname here.
        
        This defaults to "zdsock", which is created in the directory
        in which zdrun is started.
        
        daemon
        Command-line option: -d or --daemon.
        
        If this option is true, zdaemon runs in the background as a
        true daemon.  It forks a child process which becomes the
        subprocess manager, while the parent exits (making the shell
        that started it believe it is done).  The child process also
        does the following:
        
        - if the directory option is set, change into that directory
        
        - redirect stdin, stdout and stderr to /dev/null
        
        - call setsid() so it becomes a session leader
        
        - call umask() with specified value
        
        The default for this option is on by default.  The
        command-line option therefore has no effect.  To disable
        daemon mode, you must use a configuration file::
        
        <runner>
        program sleep 1
        daemon off
        </runner>
        
        directory
        Command-line option: -z or --directory.
        
        If the daemon option is true (default), this option can
        specify a directory into which zdrun.py changes as part of the
        "daemonizing".  If the daemon option is false, this option is
        ignored.
        
        backoff-limit
        Command-line option: -b or --backoff-limit.
        
        When the subprocess crashes, zdaemon inserts a one-second
        delay before it restarts it.  When the subprocess crashes
        again right away, the delay is incremented by one second, and
        so on.  What happens when the delay has reached the value of
        backoff-limit (in seconds), depends on the value of the
        forever option.  If forever is false, zdaemon gives up at
        this point, and exits.  An always-crashing subprocess will
        have been restarted exactly backoff-limit times in this case.
        If forever is true, zdaemon continues to attempt to restart
        the process, keeping the delay at backoff-limit seconds.
        
        If the subprocess stays up for more than backoff-limit
        seconds, the delay is reset to 1 second.
        
        This defaults to 10.
        
        forever
        Command-line option: -f or --forever.
        
        If this option is true, zdaemon will keep restarting a
        crashing subprocess forever.  If it is false, it will give up
        after backoff-limit crashes in a row.  See the description of
        backoff-limit for details.
        
        This is disabled by default.
        
        exit-codes
        Command-line option: -x or --exit-codes.
        
        This defaults to 0,2.
        
        If the subprocess exits with an exit status that is equal to
        one of the integers in this list, zdaemon will not restart
        it.  The default list requires some explanation.  Exit status
        0 is considered a willful successful exit; the ZEO and Zope
        server processes use this exit status when they want to stop
        without being restarted.  (Including in response to a
        SIGTERM.)  Exit status 2 is typically issued for command line
        syntax errors; in this case, restarting the program will not
        help!
        
        NOTE: this mechanism overrides the backoff-limit and forever
        options; i.e. even if forever is true, a subprocess exit
        status code in this list makes zdaemon give up.  To disable
        this, change the value to an empty list.
        
        user
        Command-line option: -u or --user.
        
        When zdaemon is started by root, this option specifies the
        user as who the the zdaemon process (and hence the daemon
        subprocess) will run.  This can be a user name or a numeric
        user id.  Both the user and the group are set from the
        corresponding password entry, using setuid() and setgid().
        This is done before zdaemon does anything else besides
        parsing its command line arguments.
        
        NOTE: when zdaemon is not started by root, specifying this
        option is an error.  (XXX This may be a mistake.)
        
        XXX The zdaemon event log file may be opened *before*
        setuid() is called.  Is this good or bad?
        
        umask
        Command-line option: -m or --umask.
        
        When daemon mode is used, this option specifies the octal umask
        of the subprocess.
        
        default-to-interactive
        If this option is true, zdaemon enters interactive mode
        when it is invoked without a positional command argument.  If
        it is false, you must use the -i or --interactive command line
        option to zdaemon to enter interactive mode.
        
        This is enabled by default.
        
        logfile
        This option specifies a log file that is the default target of
        the "logtail" zdaemon command.
        
        NOTE: This is NOT the log file to which zdaemon writes its
        logging messages!  That log file is specified by the
        <eventlog> section described below.
        
        transcript
        The name of a file in which a transcript of all output from
        the command being run will be written to when daemonized.
        
        If not specified, output from the command will be discarded.
        
        This only takes effect when the "daemon" option is enabled.
        
        prompt
        The prompt shown by the controller program.  The default must
        be provided by the application.
        
        (Note that a few other options are available to support old
        configuration files, but aren't needed any more and can generally be
        ignored.)
        
        In addition to the runner section, you can use an eventlog section
        that specified one or more logfile subsections::
        
        <eventlog>
        <logfile>
        path /var/log/foo/foo.log
        </logfile>
        
        <logfile>
        path STDOUT
        </logfile>
        </eventlog>
        
        In this example, log output is sent to a file and to standard out.
        Log output from zdaemon usually isn't very interesting but can be
        handy for debugging.
        
        ========
        Download
        ========
        
Platform: UNKNOWN
Classifier: Intended Audience :: Developers
Classifier: Intended Audience :: System Administrators
Classifier: License :: OSI Approved :: Zope Public License
Classifier: Topic :: Utilities
Classifier: Operating System :: POSIX
