1 # Autoreloading launcher.

     2 # Borrowed from Peter Hunt and the CherryPy project (http://www.cherrypy.org).

     3 # Some taken from Ian Bicking's Paste (http://pythonpaste.org/).

     4 #

     5 # Portions copyright (c) 2004, CherryPy Team (team@cherrypy.org)

     6 # All rights reserved.

     7 #

     8 # Redistribution and use in source and binary forms, with or without modification,

     9 # are permitted provided that the following conditions are met:

    10 #

    11 #     * Redistributions of source code must retain the above copyright notice,

    12 #       this list of conditions and the following disclaimer.

    13 #     * Redistributions in binary form must reproduce the above copyright notice,

    14 #       this list of conditions and the following disclaimer in the documentation

    15 #       and/or other materials provided with the distribution.

    16 #     * Neither the name of the CherryPy Team nor the names of its contributors

    17 #       may be used to endorse or promote products derived from this software

    18 #       without specific prior written permission.

    19 #

    20 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND

    21 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

    22 # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

    23 # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE

    24 # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

    25 # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

    26 # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER

    27 # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

    28 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

    29 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    30 

    31 import os, sys, time

    32 

    33 try:

    34     import thread

    35 except ImportError:

    36     import dummy_thread as thread

    37 

    38 # This import does nothing, but it's necessary to avoid some race conditions

    39 # in the threading module. See http://code.djangoproject.com/ticket/2330 .

    40 try:

    41     import threading

    42 except ImportError:

    43     pass

    44 

    45 

    46 RUN_RELOADER = True

    47 

    48 _mtimes = {}

    49 _win = (sys.platform == "win32")

    50 

    51 def code_changed():

    52     global _mtimes, _win

    53     for filename in filter(lambda v: v, map(lambda m: getattr(m, "__file__", None), sys.modules.values())):

    54         if filename.endswith(".pyc") or filename.endswith(".pyo"):

    55             filename = filename[:-1]

    56         if not os.path.exists(filename):

    57             continue # File might be in an egg, so it can't be reloaded.

    58         stat = os.stat(filename)

    59         mtime = stat.st_mtime

    60         if _win:

    61             mtime -= stat.st_ctime

    62         if filename not in _mtimes:

    63             _mtimes[filename] = mtime

    64             continue

    65         if mtime != _mtimes[filename]:

    66             _mtimes = {}

    67             return True

    68     return False

    69 

    70 def reloader_thread():

    71     while RUN_RELOADER:

    72         if code_changed():

    73             sys.exit(3) # force reload

    74         time.sleep(1)

    75 

    76 def restart_with_reloader():

    77     while True:

    78         args = [sys.executable] + sys.argv

    79         if sys.platform == "win32":

    80             args = ['"%s"' % arg for arg in args]

    81         new_environ = os.environ.copy()

    82         new_environ["RUN_MAIN"] = 'true'

    83         exit_code = os.spawnve(os.P_WAIT, sys.executable, args, new_environ)

    84         if exit_code != 3:

    85             return exit_code

    86 

    87 def python_reloader(main_func, args, kwargs):

    88     if os.environ.get("RUN_MAIN") == "true":

    89         thread.start_new_thread(main_func, args, kwargs)

    90         try:

    91             reloader_thread()

    92         except KeyboardInterrupt:

    93             pass

    94     else:

    95         try:

    96             sys.exit(restart_with_reloader())

    97         except KeyboardInterrupt:

    98             pass

    99 

   100 def jython_reloader(main_func, args, kwargs):

   101     from _systemrestart import SystemRestart

   102     thread.start_new_thread(main_func, args)

   103     while True:

   104         if code_changed():

   105             raise SystemRestart

   106         time.sleep(1)

   107 

   108 

   109 def main(main_func, args=None, kwargs=None):

   110     if args is None:

   111         args = ()

   112     if kwargs is None:

   113         kwargs = {}

   114     if sys.platform.startswith('java'):

   115         reloader = jython_reloader

   116     else:

   117         reloader = python_reloader

   118     reloader(main_func, args, kwargs)

   119