Mercurial > hg
view hgext/logtoprocess.py @ 30661:ced0d686ecb3
convert: add config option to control storing original revision
common.commit.__init__ sets saverev=True by default. The side effect
of this is that the hg sink will always set the "convert_revision"
extras key to the commit being converted.
This patch adds a config option to disable this behavior.
While most consumers will want "convert_revision" to be a) written
b) with the exact Git commit that was converted, some have use cases
that prefer otherwise. In my case, I am performing significant
rewrites of a Git repository *before* it is fed into `hg convert`.
I have to do this because `hg convert` does not easily support the kind
of transform I desire, even with extensions. (For the curious, I am
"linearizing" the history of a GitHub repo by removing merge commits
which add little value to the final history. It isn't easy to do this
during `hg convert` because of Mercurial's file copy/rename metadata
requirements.)
In my scenario, my pre-convert transform stores a "convert_revision"
key in the Git commit object containing the original Git commit ID.
I want this original Git commit ID carried forward to Mercurial. By
disabling the setting of this extra during `hg convert` and copying
the value from the Git commit object, I can have the final
"convert_revision" extra key contain the original Git commit ID. An
added test verifies this exact scenario.
This feature could likely be implemented for other VCS sources. But
until someone needs the feature, I'm inclined to hold off implementing.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Thu, 22 Dec 2016 23:28:35 -0700 |
parents | 1c5cbf28f007 |
children | 8e7feaad2d8d |
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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 from mercurial import encoding # 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(encoding.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