Mercurial > hg
view hgext/logtoprocess.py @ 30381:caba61934721
shelve: move commitfunc creation to a separate function
Special commitfuncs are created as closures at least twice in shelve's
code and one time special commitfunc is used within another closure.
They all serve very specific purposes like temporarily tweak some
configuration or enable editor, etc. This is not immediately important
to someone reading shelve code, so I think moving this logic to a separate
function is a good idea.
author | Kostia Balytskyi <ikostia@fb.com> |
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date | Thu, 10 Nov 2016 03:26:31 -0800 |
parents | 318a24b52eeb |
children | 1c5cbf28f007 |
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# logtoprocess.py - send ui.log() data to a subprocess # # Copyright 2016 Facebook, Inc. # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. """Send ui.log() data to a subprocess (EXPERIMENTAL) This extension lets you specify a shell command per ui.log() event, sending all remaining arguments to as environment variables to that command. Each positional argument to the method results in a `MSG[N]` key in the environment, starting at 1 (so `MSG1`, `MSG2`, etc.). Each keyword argument is set as a `OPT_UPPERCASE_KEY` variable (so the key is uppercased, and prefixed with `OPT_`). The original event name is passed in the `EVENT` environment variable, and the process ID of mercurial is given in `HGPID`. So given a call `ui.log('foo', 'bar', 'baz', spam='eggs'), a script configured for the `foo` event can expect an environment with `MSG1=bar`, `MSG2=baz`, and `OPT_SPAM=eggs`. Scripts are configured in the `[logtoprocess]` section, each key an event name. For example:: [logtoprocess] commandexception = echo "$MSG2$MSG3" > /var/log/mercurial_exceptions.log would log the warning message and traceback of any failed command dispatch. Scripts are run asynchronously as detached daemon processes; mercurial will not ensure that they exit cleanly. """ from __future__ import absolute_import import itertools import os import platform import subprocess import sys # Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for # extensions which SHIP WITH MERCURIAL. Non-mainline extensions should # be specifying the version(s) of Mercurial they are tested with, or # leave the attribute unspecified. testedwith = 'ships-with-hg-core' def uisetup(ui): if platform.system() == 'Windows': # no fork on Windows, but we can create a detached process # https://msdn.microsoft.com/en-us/library/windows/desktop/ms684863.aspx # No stdlib constant exists for this value DETACHED_PROCESS = 0x00000008 _creationflags = DETACHED_PROCESS | subprocess.CREATE_NEW_PROCESS_GROUP def runshellcommand(script, env): # we can't use close_fds *and* redirect stdin. I'm not sure that we # need to because the detached process has no console connection. subprocess.Popen( script, shell=True, env=env, close_fds=True, creationflags=_creationflags) else: def runshellcommand(script, env): # double-fork to completely detach from the parent process # based on http://code.activestate.com/recipes/278731 pid = os.fork() if pid: # parent return # subprocess.Popen() forks again, all we need to add is # flag the new process as a new session. if sys.version_info < (3, 2): newsession = {'preexec_fn': os.setsid} else: newsession = {'start_new_session': True} try: # connect stdin to devnull to make sure the subprocess can't # muck up that stream for mercurial. subprocess.Popen( script, shell=True, stdin=open(os.devnull, 'r'), env=env, close_fds=True, **newsession) finally: # mission accomplished, this child needs to exit and not # continue the hg process here. os._exit(0) class logtoprocessui(ui.__class__): def log(self, event, *msg, **opts): """Map log events to external commands Arguments are passed on as environment variables. """ script = self.config('logtoprocess', event) if script: if msg: # try to format the log message given the remaining # arguments try: # Python string formatting with % either uses a # dictionary *or* tuple, but not both. If we have # keyword options, assume we need a mapping. formatted = msg[0] % (opts or msg[1:]) except (TypeError, KeyError): # Failed to apply the arguments, ignore formatted = msg[0] messages = (formatted,) + msg[1:] else: messages = msg # positional arguments are listed as MSG[N] keys in the # environment msgpairs = ( ('MSG{0:d}'.format(i), str(m)) for i, m in enumerate(messages, 1)) # keyword arguments get prefixed with OPT_ and uppercased optpairs = ( ('OPT_{0}'.format(key.upper()), str(value)) for key, value in opts.iteritems()) env = dict(itertools.chain(os.environ.items(), msgpairs, optpairs), EVENT=event, HGPID=str(os.getpid())) # Connect stdin to /dev/null to prevent child processes messing # with mercurial's stdin. runshellcommand(script, env) return super(logtoprocessui, self).log(event, *msg, **opts) # Replace the class for this instance and all clones created from it: ui.__class__ = logtoprocessui