Mercurial > hg
view mercurial/rcutil.py @ 37052:8c3c47362934
wireproto: implement basic frame reading and processing
We just implemented support for writing frames. Now let's implement
support for reading them.
The bulk of the new code is for a class that maintains the state of
a server. Essentially, you construct an instance, feed frames to it,
and it tells you what you should do next. The design is inspired by
the "sans I/O" movement and the reactor pattern. We don't want to
perform I/O or any major blocking event during frame ingestion because
this arbitrarily limits ways that server pieces can be implemented.
For example, it makes it much harder to swap in an alternate
implementation based on asyncio or do crazy things like have requests
dispatch to other processes.
We do still implement readframe() which does I/O. But it is decoupled
from the server reactor. And important parsing of frame headers is
a standalone function. So I/O is only needed to obtain frame data.
Because testing server-side ingest is useful and difficult on running
servers, we create a new "debugreflect" endpoint that will echo back
to the client what was received and how it was interpreted. This could
be useful for a server admin, someone implementing a client. But
immediately, it is useful for testing: we're able to demonstrate that
frames are parsed correctly and turned into requests to run commands
without having to implement command dispatch on the server!
In addition, we implement Python level unit tests for the reactor.
This is vastly more efficient than sending requests to the
"debugreflect" endpoint and vastly more powerful for advanced
testing.
Differential Revision: https://phab.mercurial-scm.org/D2852
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 14 Mar 2018 15:25:06 -0700 |
parents | 75979c8d4572 |
children | edbcf5b239f9 |
line wrap: on
line source
# rcutil.py - utilities about config paths, special config sections etc. # # Copyright Mercurial Contributors # # 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 os from . import ( encoding, pycompat, util, ) if pycompat.iswindows: from . import scmwindows as scmplatform else: from . import scmposix as scmplatform fallbackpager = scmplatform.fallbackpager systemrcpath = scmplatform.systemrcpath userrcpath = scmplatform.userrcpath def _expandrcpath(path): '''path could be a file or a directory. return a list of file paths''' p = util.expandpath(path) if os.path.isdir(p): join = os.path.join return [join(p, f) for f, k in util.listdir(p) if f.endswith('.rc')] return [p] def envrcitems(env=None): '''Return [(section, name, value, source)] config items. The config items are extracted from environment variables specified by env, used to override systemrc, but not userrc. If env is not provided, encoding.environ will be used. ''' if env is None: env = encoding.environ checklist = [ ('EDITOR', 'ui', 'editor'), ('VISUAL', 'ui', 'editor'), ('PAGER', 'pager', 'pager'), ] result = [] for envname, section, configname in checklist: if envname not in env: continue result.append((section, configname, env[envname], '$%s' % envname)) return result def defaultrcpath(): '''return rc paths in default.d''' path = [] defaultpath = os.path.join(util.datapath, 'default.d') if os.path.isdir(defaultpath): path = _expandrcpath(defaultpath) return path def rccomponents(): '''return an ordered [(type, obj)] about where to load configs. respect $HGRCPATH. if $HGRCPATH is empty, only .hg/hgrc of current repo is used. if $HGRCPATH is not set, the platform default will be used. if a directory is provided, *.rc files under it will be used. type could be either 'path' or 'items', if type is 'path', obj is a string, and is the config file path. if type is 'items', obj is a list of (section, name, value, source) that should fill the config directly. ''' envrc = ('items', envrcitems()) if 'HGRCPATH' in encoding.environ: # assume HGRCPATH is all about user configs so environments can be # overridden. _rccomponents = [envrc] for p in encoding.environ['HGRCPATH'].split(pycompat.ospathsep): if not p: continue _rccomponents.extend(('path', p) for p in _expandrcpath(p)) else: normpaths = lambda paths: [('path', os.path.normpath(p)) for p in paths] _rccomponents = normpaths(defaultrcpath() + systemrcpath()) _rccomponents.append(envrc) _rccomponents.extend(normpaths(userrcpath())) return _rccomponents def defaultpagerenv(): '''return a dict of default environment variables and their values, intended to be set before starting a pager. ''' return {'LESS': 'FRX', 'LV': '-c'}