##// END OF EJS Templates
util: compression APIs to support revlog compression...
util: compression APIs to support revlog compression As part of "zstd all of the things," we need to teach revlogs to use non-zlib compression formats. Because we're routing all compression via the "compression manager" and "compression engine" APIs, we need to introduction functionality there for performing revlog operations. Ideally, revlog compression and decompression operations would be implemented in terms of simple "compress" and "decompress" primitives. However, there are a few considerations that make us want to have a specialized primitive for handling revlogs: 1) Performance. Revlogs tend to do compression and especially decompression operations in batches. Any overhead for e.g. instantiating a "context" for performing an operation can be noticed. For this reason, our "revlog compressor" primitive is reusable. For zstd, we reuse the same compression "context" for multiple operations. I've measured this to have a performance impact versus constructing new contexts for each operation. 2) Specialization. By having a primitive dedicated to revlog use, we can make revlog-specific choices and leave the door open for more functionality in the future. For example, the zstd revlog compressor may one day make use of dictionary compression. A future patch will introduce a decompress() on the compressor object. The code for the zlib compressor is basically copied from revlog.compress(). Although it doesn't handle the empty input case, the null first byte case, and the 'u' prefix case. These cases will continue to be handled in revlog.py once that code is ported to use this API.

File last commit:

r27046:37fcfe52 default
r30794:31e1f0d4 default
Show More
request.py
152 lines | 5.3 KiB | text/x-python | PythonLexer
# hgweb/request.py - An http request from either CGI or the standalone server.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net>
# 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 cgi
import errno
import socket
from .common import (
ErrorResponse,
HTTP_NOT_MODIFIED,
statusmessage,
)
from .. import (
util,
)
shortcuts = {
'cl': [('cmd', ['changelog']), ('rev', None)],
'sl': [('cmd', ['shortlog']), ('rev', None)],
'cs': [('cmd', ['changeset']), ('node', None)],
'f': [('cmd', ['file']), ('filenode', None)],
'fl': [('cmd', ['filelog']), ('filenode', None)],
'fd': [('cmd', ['filediff']), ('node', None)],
'fa': [('cmd', ['annotate']), ('filenode', None)],
'mf': [('cmd', ['manifest']), ('manifest', None)],
'ca': [('cmd', ['archive']), ('node', None)],
'tags': [('cmd', ['tags'])],
'tip': [('cmd', ['changeset']), ('node', ['tip'])],
'static': [('cmd', ['static']), ('file', None)]
}
def normalize(form):
# first expand the shortcuts
for k in shortcuts.iterkeys():
if k in form:
for name, value in shortcuts[k]:
if value is None:
value = form[k]
form[name] = value
del form[k]
# And strip the values
for k, v in form.iteritems():
form[k] = [i.strip() for i in v]
return form
class wsgirequest(object):
"""Higher-level API for a WSGI request.
WSGI applications are invoked with 2 arguments. They are used to
instantiate instances of this class, which provides higher-level APIs
for obtaining request parameters, writing HTTP output, etc.
"""
def __init__(self, wsgienv, start_response):
version = wsgienv['wsgi.version']
if (version < (1, 0)) or (version >= (2, 0)):
raise RuntimeError("Unknown and unsupported WSGI version %d.%d"
% version)
self.inp = wsgienv['wsgi.input']
self.err = wsgienv['wsgi.errors']
self.threaded = wsgienv['wsgi.multithread']
self.multiprocess = wsgienv['wsgi.multiprocess']
self.run_once = wsgienv['wsgi.run_once']
self.env = wsgienv
self.form = normalize(cgi.parse(self.inp,
self.env,
keep_blank_values=1))
self._start_response = start_response
self.server_write = None
self.headers = []
def __iter__(self):
return iter([])
def read(self, count=-1):
return self.inp.read(count)
def drain(self):
'''need to read all data from request, httplib is half-duplex'''
length = int(self.env.get('CONTENT_LENGTH') or 0)
for s in util.filechunkiter(self.inp, limit=length):
pass
def respond(self, status, type, filename=None, body=None):
if self._start_response is not None:
self.headers.append(('Content-Type', type))
if filename:
filename = (filename.rpartition('/')[-1]
.replace('\\', '\\\\').replace('"', '\\"'))
self.headers.append(('Content-Disposition',
'inline; filename="%s"' % filename))
if body is not None:
self.headers.append(('Content-Length', str(len(body))))
for k, v in self.headers:
if not isinstance(v, str):
raise TypeError('header value must be string: %r' % (v,))
if isinstance(status, ErrorResponse):
self.headers.extend(status.headers)
if status.code == HTTP_NOT_MODIFIED:
# RFC 2616 Section 10.3.5: 304 Not Modified has cases where
# it MUST NOT include any headers other than these and no
# body
self.headers = [(k, v) for (k, v) in self.headers if
k in ('Date', 'ETag', 'Expires',
'Cache-Control', 'Vary')]
status = statusmessage(status.code, str(status))
elif status == 200:
status = '200 Script output follows'
elif isinstance(status, int):
status = statusmessage(status)
self.server_write = self._start_response(status, self.headers)
self._start_response = None
self.headers = []
if body is not None:
self.write(body)
self.server_write = None
def write(self, thing):
if thing:
try:
self.server_write(thing)
except socket.error as inst:
if inst[0] != errno.ECONNRESET:
raise
def writelines(self, lines):
for line in lines:
self.write(line)
def flush(self):
return None
def close(self):
return None
def wsgiapplication(app_maker):
'''For compatibility with old CGI scripts. A plain hgweb() or hgwebdir()
can and should now be used as a WSGI application.'''
application = app_maker()
def run_wsgi(env, respond):
return application(env, respond)
return run_wsgi