#! %%PYTHON_CMD%%

################################################################################
# Author:        Jean-Baptiste Quenot <jb.quenot@caraldi.com>
# Purpose:       Manage resin pid file and log files
# Date Created:  2005-01-21 15:43:19
################################################################################
# Copyright (c) 2004, Jean-Baptiste Quenot <jb.quenot@caraldi.com>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice, this
#   list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright notice,
#   this list of conditions and the following disclaimer in the documentation
#   and/or other materials provided with the distribution.
# * The name of the contributors may not be used to endorse or promote products
#   derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
################################################################################
#
# Files handled by this script (pid file, log files) must reside in a writable
# directory, ie the directory must be owned by the user running the program.

import sys, os, signal, time, stat, re

#    -socketwait 12345
#    -stdout $APP_HOME/log/stdout.log
#    -stderr $APP_HOME/log/stderr.log

def readProcessId():
    f = open(PID_FILE, 'r')
    pid = int(f.readline())
    f.close()
    return pid

def isProgramRunning(pid):
    # Send a dummy signal to the process.  If it died, an exception is
    # thrown
    try:
        os.kill(pid, signal.SIGCONT)
        return 1
    except OSError:
        return 0

def usage():
    print >> sys.stderr, "Usage: %s {start|stop|restart}" % sys.argv[0]

def start():
    cwd = os.getcwd()
    if os.path.exists(PID_FILE):
        # Read the process id
        pid = readProcessId()

        if isProgramRunning(pid):
            print >> sys.stderr, '%s already started' % APP_NAME
            sys.exit(3)

    if not(os.path.exists(COMMAND)):
        print >> sys.stderr, '%s cannot be found' % COMMAND
        sys.exit(3)

    # Append program output to a log file
    l = open(LOG_FILE, 'a')
    orig_stderr = os.dup(sys.stderr.fileno())
    os.dup2(l.fileno(), sys.stdout.fileno())
    os.dup2(l.fileno(), sys.stderr.fileno())

    finfo = os.stat(COMMAND)[stat.ST_MODE]
    executable = stat.S_IMODE(finfo) & 0111
    if not(executable):
        sys.stderr = os.fdopen(orig_stderr, 'w')
        print >> sys.stderr, 'Cannot run %s, execute bit is missing' % COMMAND
        sys.exit(5)

    if APP_HOME:
        # Change current directory to APP_HOME
        os.chdir(APP_HOME)

    # Start program in the background
    pid = os.spawnv(os.P_NOWAIT, COMMAND, ARGS)

    # Wait a little
    time.sleep(.4)
    (status_pid, status) = os.waitpid(pid, os.WNOHANG)

    # Check program exit status, if available
    if status_pid != 0 and os.WIFEXITED(status):
        sys.stderr = os.fdopen(orig_stderr, 'w')
        print >> sys.stderr, 'Could not start %s.  Check %s for errors.' % (APP_NAME, LOG_FILE)
        sys.exit(2)

    # It's alive, so write down the process id
    os.chdir(cwd)
    f = open(PID_FILE, 'w')
    print >> f, pid
    f.close()

def warnNotRunning():
    if sys.argv[1] == "stop":
        print >> sys.stderr, '%s is not running' % APP_NAME
    else:
        print >> sys.stderr, 'Warning: %s was not running' % APP_NAME

def cleanup():
    os.unlink(PID_FILE)

def stop():
    if os.path.exists(PID_FILE):
        # Read the process id
        pid = readProcessId()
    else:
        warnNotRunning()
        return

    if not(isProgramRunning(pid)):
        warnNotRunning()
        cleanup()
        return

    # Terminate program
    os.kill(pid, signal.SIGTERM)

    while isProgramRunning(pid):
        time.sleep(.1)

    cleanup()

if __name__ == '__main__':
    LOG_FILE = "%%LOG_FILE%%"
    APP_NAME = "%%APP_NAME%%"
    APP_HOME = "%%APP_HOME%%"
    PID_FILE = "%%PID_FILE%%"
    COMMAND = "%%PREFIX%%/bin/java"
    ARGS = [COMMAND]

    ARGS += sys.argv[1:-1]

    ARGS += [
        "-Djetty.home=%%APP_HOME%%",
        "-jar",
        "%%APP_HOME%%/start.jar"
        ]

    os.environ['PATH'] = "%%LOCALBASE%%/bin:/usr/bin:/bin"

    if len(sys.argv) < 2:
        usage()
        sys.exit(1)

    if sys.argv[-1] == "start":
        start()

    elif sys.argv[-1] == "stop":
        stop()

    elif sys.argv[-1] == "restart":
        stop()
        start()

    else:
        usage()
        sys.exit(1)