Mercurial > hg
view mercurial/i18n.py @ 37631:2f626233859b
wireproto: implement batching on peer executor interface
This is a bit more complicated than non-batch requests because we
need to buffer sends until the last request arrives *and* we need
to support resolving futures as data arrives from the remote.
In a classical concurrent.futures executor model, the future
"starts" as soon as it is submitted. However, we have nothing to
start until the last command is submitted.
If we did nothing, calling result() would deadlock, since the future
hasn't "started." So in the case where we queue the command, we return
a special future type whose result() will trigger sendcommands().
This eliminates the deadlock potential. It also serves as a check
against callers who may be calling result() prematurely, as it will
prevent any subsequent callcommands() from working. This behavior
is slightly annoying and a bit restrictive. But it's the world
that half duplex connections forces on us.
In order to support streaming responses, we were previously using
a generator. But with a futures-based API, we're using futures
and not generators. So in order to get streaming, we need a
background thread to read data from the server.
The approach taken in this patch is to leverage the ThreadPoolExecutor
from concurrent.futures for managing a background thread. We create
an executor and future that resolves when all response data is
processed (or an error occurs). When exiting the context manager,
we wait on that background reading before returning.
I was hoping we could manually spin up a threading.Thread and this
would be simple. But I ran into a few deadlocks when implementing.
After looking at the source code to concurrent.futures, I figured
it would just be easier to use a ThreadPoolExecutor than implement
all the code needed to manually manage a thread.
To prove this works, a use of the batch API in discovery has been
updated.
Differential Revision: https://phab.mercurial-scm.org/D3269
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Fri, 13 Apr 2018 11:02:34 -0700 |
parents | 5bc7ff103081 |
children | 79dd61a4554f |
line wrap: on
line source
# i18n.py - internationalization support for mercurial # # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import gettext as gettextmod import locale import os import sys from . import ( encoding, pycompat, ) # modelled after templater.templatepath: if getattr(sys, 'frozen', None) is not None: module = pycompat.sysexecutable else: module = pycompat.fsencode(__file__) try: unicode except NameError: unicode = str _languages = None if (pycompat.iswindows and 'LANGUAGE' not in encoding.environ and 'LC_ALL' not in encoding.environ and 'LC_MESSAGES' not in encoding.environ and 'LANG' not in encoding.environ): # Try to detect UI language by "User Interface Language Management" API # if no locale variables are set. Note that locale.getdefaultlocale() # uses GetLocaleInfo(), which may be different from UI language. # (See http://msdn.microsoft.com/en-us/library/dd374098(v=VS.85).aspx ) try: import ctypes langid = ctypes.windll.kernel32.GetUserDefaultUILanguage() _languages = [locale.windows_locale[langid]] except (ImportError, AttributeError, KeyError): # ctypes not found or unknown langid pass _ugettext = None def setdatapath(datapath): datapath = pycompat.fsdecode(datapath) localedir = os.path.join(datapath, r'locale') t = gettextmod.translation(r'hg', localedir, _languages, fallback=True) global _ugettext try: _ugettext = t.ugettext except AttributeError: _ugettext = t.gettext _msgcache = {} # encoding: {message: translation} def gettext(message): """Translate message. The message is looked up in the catalog to get a Unicode string, which is encoded in the local encoding before being returned. Important: message is restricted to characters in the encoding given by sys.getdefaultencoding() which is most likely 'ascii'. """ # If message is None, t.ugettext will return u'None' as the # translation whereas our callers expect us to return None. if message is None or not _ugettext: return message cache = _msgcache.setdefault(encoding.encoding, {}) if message not in cache: if type(message) is unicode: # goofy unicode docstrings in test paragraphs = message.split(u'\n\n') else: paragraphs = [p.decode("ascii") for p in message.split('\n\n')] # Be careful not to translate the empty string -- it holds the # meta data of the .po file. u = u'\n\n'.join([p and _ugettext(p) or u'' for p in paragraphs]) try: # encoding.tolocal cannot be used since it will first try to # decode the Unicode string. Calling u.decode(enc) really # means u.encode(sys.getdefaultencoding()).decode(enc). Since # the Python encoding defaults to 'ascii', this fails if the # translated string use non-ASCII characters. encodingstr = pycompat.sysstr(encoding.encoding) cache[message] = u.encode(encodingstr, "replace") except LookupError: # An unknown encoding results in a LookupError. cache[message] = message return cache[message] def _plain(): if ('HGPLAIN' not in encoding.environ and 'HGPLAINEXCEPT' not in encoding.environ): return False exceptions = encoding.environ.get('HGPLAINEXCEPT', '').strip().split(',') return 'i18n' not in exceptions if _plain(): _ = lambda message: message else: _ = gettext