Mercurial > hg
view mercurial/httppeer.py @ 42043:1fac9b931d46
compression: introduce a `storage.revlog.zlib.level` configuration
This option control the zlib compression level used when compression revlog
chunk.
This is also a good excuse to pave the way for a similar configuration option
for the zstd compression engine. Having a dedicated option for each compression
algorithm is useful because they don't support the same range of values.
Using a higher zlib compression impact CPU consumption at compression time, but
does not directly affected decompression time. However dealing with small
compressed chunk can directly help decompression and indirectly help other
revlog logic.
I ran some basic test on repositories using different level. I am using the
mercurial, pypy, netbeans and mozilla-central clone from our benchmark suite.
All tested repository use sparse-revlog and got all their delta recomputed.
The different compression level has a small effect on the repository size
(about 10% variation in the total range). My quick analysis is that revlog
mostly store small delta, that are not affected by the compression level much.
So the variation probably mostly comes from better compression of the snapshots
revisions, and snapshot revision only represent a small portion of the
repository content.
I also made some basic timings measurements. The "read" timings are gathered using
simple run of `hg perfrevlogrevisions`, the "write" timings using `hg
perfrevlogwrite` (restricted to the last 5000 revisions for netbeans and
mozilla central). The timings are gathered on a generic machine, (not one of
our performance locked machine), so small variation might not be meaningful.
However large trend remains relevant.
Keep in mind that these numbers are not pure compression/decompression time.
They also involve the full revlog logic. In particular the difference in chunk
size has an impact on the delta chain structure, affecting performance when
writing or reading them.
On read/write performance, the compression level has a bigger impact.
Counter-intuitively, the higher compression levels improve "write" performance
for the large repositories in our tested setting. Maybe because the last 5000
delta chain end up having a very different shape in this specific spot? Or maybe
because of a more general trend of better delta chains thanks to the smaller
chunk and snapshot.
This series does not intend to change the default compression level. However,
these result call for a deeper analysis of this performance difference in the
future.
Full data
=========
repo level .hg/store size 00manifest.d read write
----------------------------------------------------------------
mercurial 1 49,402,813 5,963,475 0.170159 53.250304
mercurial 6 47,197,397 5,875,730 0.182820 56.264320
mercurial 9 47,121,596 5,849,781 0.189219 56.293612
pypy 1 370,830,572 28,462,425 2.679217 460.721984
pypy 6 340,112,317 27,648,747 2.768691 467.537158
pypy 9 338,360,736 27,639,003 2.763495 476.589918
netbeans 1 1,281,847,810 165,495,457 122.477027 520.560316
netbeans 6 1,205,284,353 159,161,207 139.876147 715.930400
netbeans 9 1,197,135,671 155,034,586 141.620281 678.297064
mozilla 1 2,775,497,186 298,527,987 147.867662 751.263721
mozilla 6 2,596,856,420 286,597,671 170.572118 987.056093
mozilla 9 2,587,542,494 287,018,264 163.622338 739.803002
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Wed, 27 Mar 2019 18:35:27 +0100 |
parents | a9b609fbe39c |
children | 69921d02daaf |
line wrap: on
line source
# httppeer.py - HTTP repository proxy classes for mercurial # # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> # Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.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 errno import io import os import socket import struct import weakref from .i18n import _ from . import ( bundle2, error, httpconnection, pycompat, repository, statichttprepo, url as urlmod, util, wireprotoframing, wireprototypes, wireprotov1peer, wireprotov2peer, wireprotov2server, ) from .utils import ( cborutil, interfaceutil, stringutil, ) httplib = util.httplib urlerr = util.urlerr urlreq = util.urlreq def encodevalueinheaders(value, header, limit): """Encode a string value into multiple HTTP headers. ``value`` will be encoded into 1 or more HTTP headers with the names ``header-<N>`` where ``<N>`` is an integer starting at 1. Each header name + value will be at most ``limit`` bytes long. Returns an iterable of 2-tuples consisting of header names and values as native strings. """ # HTTP Headers are ASCII. Python 3 requires them to be unicodes, # not bytes. This function always takes bytes in as arguments. fmt = pycompat.strurl(header) + r'-%s' # Note: it is *NOT* a bug that the last bit here is a bytestring # and not a unicode: we're just getting the encoded length anyway, # and using an r-string to make it portable between Python 2 and 3 # doesn't work because then the \r is a literal backslash-r # instead of a carriage return. valuelen = limit - len(fmt % r'000') - len(': \r\n') result = [] n = 0 for i in pycompat.xrange(0, len(value), valuelen): n += 1 result.append((fmt % str(n), pycompat.strurl(value[i:i + valuelen]))) return result class _multifile(object): def __init__(self, *fileobjs): for f in fileobjs: if not util.safehasattr(f, 'length'): raise ValueError( '_multifile only supports file objects that ' 'have a length but this one does not:', type(f), f) self._fileobjs = fileobjs self._index = 0 @property def length(self): return sum(f.length for f in self._fileobjs) def read(self, amt=None): if amt <= 0: return ''.join(f.read() for f in self._fileobjs) parts = [] while amt and self._index < len(self._fileobjs): parts.append(self._fileobjs[self._index].read(amt)) got = len(parts[-1]) if got < amt: self._index += 1 amt -= got return ''.join(parts) def seek(self, offset, whence=os.SEEK_SET): if whence != os.SEEK_SET: raise NotImplementedError( '_multifile does not support anything other' ' than os.SEEK_SET for whence on seek()') if offset != 0: raise NotImplementedError( '_multifile only supports seeking to start, but that ' 'could be fixed if you need it') for f in self._fileobjs: f.seek(0) self._index = 0 def makev1commandrequest(ui, requestbuilder, caps, capablefn, repobaseurl, cmd, args): """Make an HTTP request to run a command for a version 1 client. ``caps`` is a set of known server capabilities. The value may be None if capabilities are not yet known. ``capablefn`` is a function to evaluate a capability. ``cmd``, ``args``, and ``data`` define the command, its arguments, and raw data to pass to it. """ if cmd == 'pushkey': args['data'] = '' data = args.pop('data', None) headers = args.pop('headers', {}) ui.debug("sending %s command\n" % cmd) q = [('cmd', cmd)] headersize = 0 # Important: don't use self.capable() here or else you end up # with infinite recursion when trying to look up capabilities # for the first time. postargsok = caps is not None and 'httppostargs' in caps # Send arguments via POST. if postargsok and args: strargs = urlreq.urlencode(sorted(args.items())) if not data: data = strargs else: if isinstance(data, bytes): i = io.BytesIO(data) i.length = len(data) data = i argsio = io.BytesIO(strargs) argsio.length = len(strargs) data = _multifile(argsio, data) headers[r'X-HgArgs-Post'] = len(strargs) elif args: # Calling self.capable() can infinite loop if we are calling # "capabilities". But that command should never accept wire # protocol arguments. So this should never happen. assert cmd != 'capabilities' httpheader = capablefn('httpheader') if httpheader: headersize = int(httpheader.split(',', 1)[0]) # Send arguments via HTTP headers. if headersize > 0: # The headers can typically carry more data than the URL. encargs = urlreq.urlencode(sorted(args.items())) for header, value in encodevalueinheaders(encargs, 'X-HgArg', headersize): headers[header] = value # Send arguments via query string (Mercurial <1.9). else: q += sorted(args.items()) qs = '?%s' % urlreq.urlencode(q) cu = "%s%s" % (repobaseurl, qs) size = 0 if util.safehasattr(data, 'length'): size = data.length elif data is not None: size = len(data) if data is not None and r'Content-Type' not in headers: headers[r'Content-Type'] = r'application/mercurial-0.1' # Tell the server we accept application/mercurial-0.2 and multiple # compression formats if the server is capable of emitting those # payloads. # Note: Keep this set empty by default, as client advertisement of # protocol parameters should only occur after the handshake. protoparams = set() mediatypes = set() if caps is not None: mt = capablefn('httpmediatype') if mt: protoparams.add('0.1') mediatypes = set(mt.split(',')) protoparams.add('partial-pull') if '0.2tx' in mediatypes: protoparams.add('0.2') if '0.2tx' in mediatypes and capablefn('compression'): # We /could/ compare supported compression formats and prune # non-mutually supported or error if nothing is mutually supported. # For now, send the full list to the server and have it error. comps = [e.wireprotosupport().name for e in util.compengines.supportedwireengines(util.CLIENTROLE)] protoparams.add('comp=%s' % ','.join(comps)) if protoparams: protoheaders = encodevalueinheaders(' '.join(sorted(protoparams)), 'X-HgProto', headersize or 1024) for header, value in protoheaders: headers[header] = value varyheaders = [] for header in headers: if header.lower().startswith(r'x-hg'): varyheaders.append(header) if varyheaders: headers[r'Vary'] = r','.join(sorted(varyheaders)) req = requestbuilder(pycompat.strurl(cu), data, headers) if data is not None: ui.debug("sending %d bytes\n" % size) req.add_unredirected_header(r'Content-Length', r'%d' % size) return req, cu, qs def _reqdata(req): """Get request data, if any. If no data, returns None.""" if pycompat.ispy3: return req.data if not req.has_data(): return None return req.get_data() def sendrequest(ui, opener, req): """Send a prepared HTTP request. Returns the response object. """ dbg = ui.debug if (ui.debugflag and ui.configbool('devel', 'debug.peer-request')): line = 'devel-peer-request: %s\n' dbg(line % '%s %s' % (pycompat.bytesurl(req.get_method()), pycompat.bytesurl(req.get_full_url()))) hgargssize = None for header, value in sorted(req.header_items()): header = pycompat.bytesurl(header) value = pycompat.bytesurl(value) if header.startswith('X-hgarg-'): if hgargssize is None: hgargssize = 0 hgargssize += len(value) else: dbg(line % ' %s %s' % (header, value)) if hgargssize is not None: dbg(line % ' %d bytes of commands arguments in headers' % hgargssize) data = _reqdata(req) if data is not None: length = getattr(data, 'length', None) if length is None: length = len(data) dbg(line % ' %d bytes of data' % length) start = util.timer() res = None try: res = opener.open(req) except urlerr.httperror as inst: if inst.code == 401: raise error.Abort(_('authorization failed')) raise except httplib.HTTPException as inst: ui.debug('http error requesting %s\n' % util.hidepassword(req.get_full_url())) ui.traceback() raise IOError(None, inst) finally: if ui.debugflag and ui.configbool('devel', 'debug.peer-request'): code = res.code if res else -1 dbg(line % ' finished in %.4f seconds (%d)' % (util.timer() - start, code)) # Insert error handlers for common I/O failures. urlmod.wrapresponse(res) return res class RedirectedRepoError(error.RepoError): def __init__(self, msg, respurl): super(RedirectedRepoError, self).__init__(msg) self.respurl = respurl def parsev1commandresponse(ui, baseurl, requrl, qs, resp, compressible, allowcbor=False): # record the url we got redirected to redirected = False respurl = pycompat.bytesurl(resp.geturl()) if respurl.endswith(qs): respurl = respurl[:-len(qs)] qsdropped = False else: qsdropped = True if baseurl.rstrip('/') != respurl.rstrip('/'): redirected = True if not ui.quiet: ui.warn(_('real URL is %s\n') % respurl) try: proto = pycompat.bytesurl(resp.getheader(r'content-type', r'')) except AttributeError: proto = pycompat.bytesurl(resp.headers.get(r'content-type', r'')) safeurl = util.hidepassword(baseurl) if proto.startswith('application/hg-error'): raise error.OutOfBandError(resp.read()) # Pre 1.0 versions of Mercurial used text/plain and # application/hg-changegroup. We don't support such old servers. if not proto.startswith('application/mercurial-'): ui.debug("requested URL: '%s'\n" % util.hidepassword(requrl)) msg = _("'%s' does not appear to be an hg repository:\n" "---%%<--- (%s)\n%s\n---%%<---\n") % ( safeurl, proto or 'no content-type', resp.read(1024)) # Some servers may strip the query string from the redirect. We # raise a special error type so callers can react to this specially. if redirected and qsdropped: raise RedirectedRepoError(msg, respurl) else: raise error.RepoError(msg) try: subtype = proto.split('-', 1)[1] # Unless we end up supporting CBOR in the legacy wire protocol, # this should ONLY be encountered for the initial capabilities # request during handshake. if subtype == 'cbor': if allowcbor: return respurl, proto, resp else: raise error.RepoError(_('unexpected CBOR response from ' 'server')) version_info = tuple([int(n) for n in subtype.split('.')]) except ValueError: raise error.RepoError(_("'%s' sent a broken Content-Type " "header (%s)") % (safeurl, proto)) # TODO consider switching to a decompression reader that uses # generators. if version_info == (0, 1): if compressible: resp = util.compengines['zlib'].decompressorreader(resp) elif version_info == (0, 2): # application/mercurial-0.2 always identifies the compression # engine in the payload header. elen = struct.unpack('B', util.readexactly(resp, 1))[0] ename = util.readexactly(resp, elen) engine = util.compengines.forwiretype(ename) resp = engine.decompressorreader(resp) else: raise error.RepoError(_("'%s' uses newer protocol %s") % (safeurl, subtype)) return respurl, proto, resp class httppeer(wireprotov1peer.wirepeer): def __init__(self, ui, path, url, opener, requestbuilder, caps): self.ui = ui self._path = path self._url = url self._caps = caps self._urlopener = opener self._requestbuilder = requestbuilder def __del__(self): for h in self._urlopener.handlers: h.close() getattr(h, "close_all", lambda: None)() # Begin of ipeerconnection interface. def url(self): return self._path def local(self): return None def peer(self): return self def canpush(self): return True def close(self): try: reqs, sent, recv = (self._urlopener.requestscount, self._urlopener.sentbytescount, self._urlopener.receivedbytescount) except AttributeError: return self.ui.note(_('(sent %d HTTP requests and %d bytes; ' 'received %d bytes in responses)\n') % (reqs, sent, recv)) # End of ipeerconnection interface. # Begin of ipeercommands interface. def capabilities(self): return self._caps # End of ipeercommands interface. def _callstream(self, cmd, _compressible=False, **args): args = pycompat.byteskwargs(args) req, cu, qs = makev1commandrequest(self.ui, self._requestbuilder, self._caps, self.capable, self._url, cmd, args) resp = sendrequest(self.ui, self._urlopener, req) self._url, ct, resp = parsev1commandresponse(self.ui, self._url, cu, qs, resp, _compressible) return resp def _call(self, cmd, **args): fp = self._callstream(cmd, **args) try: return fp.read() finally: # if using keepalive, allow connection to be reused fp.close() def _callpush(self, cmd, cg, **args): # have to stream bundle to a temp file because we do not have # http 1.1 chunked transfer. types = self.capable('unbundle') try: types = types.split(',') except AttributeError: # servers older than d1b16a746db6 will send 'unbundle' as a # boolean capability. They only support headerless/uncompressed # bundles. types = [""] for x in types: if x in bundle2.bundletypes: type = x break tempname = bundle2.writebundle(self.ui, cg, None, type) fp = httpconnection.httpsendfile(self.ui, tempname, "rb") headers = {r'Content-Type': r'application/mercurial-0.1'} try: r = self._call(cmd, data=fp, headers=headers, **args) vals = r.split('\n', 1) if len(vals) < 2: raise error.ResponseError(_("unexpected response:"), r) return vals except urlerr.httperror: # Catch and re-raise these so we don't try and treat them # like generic socket errors. They lack any values in # .args on Python 3 which breaks our socket.error block. raise except socket.error as err: if err.args[0] in (errno.ECONNRESET, errno.EPIPE): raise error.Abort(_('push failed: %s') % err.args[1]) raise error.Abort(err.args[1]) finally: fp.close() os.unlink(tempname) def _calltwowaystream(self, cmd, fp, **args): fh = None fp_ = None filename = None try: # dump bundle to disk fd, filename = pycompat.mkstemp(prefix="hg-bundle-", suffix=".hg") fh = os.fdopen(fd, r"wb") d = fp.read(4096) while d: fh.write(d) d = fp.read(4096) fh.close() # start http push fp_ = httpconnection.httpsendfile(self.ui, filename, "rb") headers = {r'Content-Type': r'application/mercurial-0.1'} return self._callstream(cmd, data=fp_, headers=headers, **args) finally: if fp_ is not None: fp_.close() if fh is not None: fh.close() os.unlink(filename) def _callcompressable(self, cmd, **args): return self._callstream(cmd, _compressible=True, **args) def _abort(self, exception): raise exception def sendv2request(ui, opener, requestbuilder, apiurl, permission, requests, redirect): wireprotoframing.populatestreamencoders() uiencoders = ui.configlist(b'experimental', b'httppeer.v2-encoder-order') if uiencoders: encoders = [] for encoder in uiencoders: if encoder not in wireprotoframing.STREAM_ENCODERS: ui.warn(_(b'wire protocol version 2 encoder referenced in ' b'config (%s) is not known; ignoring\n') % encoder) else: encoders.append(encoder) else: encoders = wireprotoframing.STREAM_ENCODERS_ORDER reactor = wireprotoframing.clientreactor(ui, hasmultiplesend=False, buffersends=True, clientcontentencoders=encoders) handler = wireprotov2peer.clienthandler(ui, reactor, opener=opener, requestbuilder=requestbuilder) url = '%s/%s' % (apiurl, permission) if len(requests) > 1: url += '/multirequest' else: url += '/%s' % requests[0][0] ui.debug('sending %d commands\n' % len(requests)) for command, args, f in requests: ui.debug('sending command %s: %s\n' % ( command, stringutil.pprint(args, indent=2))) assert not list(handler.callcommand(command, args, f, redirect=redirect)) # TODO stream this. body = b''.join(map(bytes, handler.flushcommands())) # TODO modify user-agent to reflect v2 headers = { r'Accept': wireprotov2server.FRAMINGTYPE, r'Content-Type': wireprotov2server.FRAMINGTYPE, } req = requestbuilder(pycompat.strurl(url), body, headers) req.add_unredirected_header(r'Content-Length', r'%d' % len(body)) try: res = opener.open(req) except urlerr.httperror as e: if e.code == 401: raise error.Abort(_('authorization failed')) raise except httplib.HTTPException as e: ui.traceback() raise IOError(None, e) return handler, res class queuedcommandfuture(pycompat.futures.Future): """Wraps result() on command futures to trigger submission on call.""" def result(self, timeout=None): if self.done(): return pycompat.futures.Future.result(self, timeout) self._peerexecutor.sendcommands() # sendcommands() will restore the original __class__ and self.result # will resolve to Future.result. return self.result(timeout) @interfaceutil.implementer(repository.ipeercommandexecutor) class httpv2executor(object): def __init__(self, ui, opener, requestbuilder, apiurl, descriptor, redirect): self._ui = ui self._opener = opener self._requestbuilder = requestbuilder self._apiurl = apiurl self._descriptor = descriptor self._redirect = redirect self._sent = False self._closed = False self._neededpermissions = set() self._calls = [] self._futures = weakref.WeakSet() self._responseexecutor = None self._responsef = None def __enter__(self): return self def __exit__(self, exctype, excvalue, exctb): self.close() def callcommand(self, command, args): if self._sent: raise error.ProgrammingError('callcommand() cannot be used after ' 'commands are sent') if self._closed: raise error.ProgrammingError('callcommand() cannot be used after ' 'close()') # The service advertises which commands are available. So if we attempt # to call an unknown command or pass an unknown argument, we can screen # for this. if command not in self._descriptor['commands']: raise error.ProgrammingError( 'wire protocol command %s is not available' % command) cmdinfo = self._descriptor['commands'][command] unknownargs = set(args.keys()) - set(cmdinfo.get('args', {})) if unknownargs: raise error.ProgrammingError( 'wire protocol command %s does not accept argument: %s' % ( command, ', '.join(sorted(unknownargs)))) self._neededpermissions |= set(cmdinfo['permissions']) # TODO we /could/ also validate types here, since the API descriptor # includes types... f = pycompat.futures.Future() # Monkeypatch it so result() triggers sendcommands(), otherwise result() # could deadlock. f.__class__ = queuedcommandfuture f._peerexecutor = self self._futures.add(f) self._calls.append((command, args, f)) return f def sendcommands(self): if self._sent: return if not self._calls: return self._sent = True # Unhack any future types so caller sees a clean type and so we # break reference cycle. for f in self._futures: if isinstance(f, queuedcommandfuture): f.__class__ = pycompat.futures.Future f._peerexecutor = None # Mark the future as running and filter out cancelled futures. calls = [(command, args, f) for command, args, f in self._calls if f.set_running_or_notify_cancel()] # Clear out references, prevent improper object usage. self._calls = None if not calls: return permissions = set(self._neededpermissions) if 'push' in permissions and 'pull' in permissions: permissions.remove('pull') if len(permissions) > 1: raise error.RepoError(_('cannot make request requiring multiple ' 'permissions: %s') % _(', ').join(sorted(permissions))) permission = { 'push': 'rw', 'pull': 'ro', }[permissions.pop()] handler, resp = sendv2request( self._ui, self._opener, self._requestbuilder, self._apiurl, permission, calls, self._redirect) # TODO we probably want to validate the HTTP code, media type, etc. self._responseexecutor = pycompat.futures.ThreadPoolExecutor(1) self._responsef = self._responseexecutor.submit(self._handleresponse, handler, resp) def close(self): if self._closed: return self.sendcommands() self._closed = True if not self._responsef: return # TODO ^C here may not result in immediate program termination. try: self._responsef.result() finally: self._responseexecutor.shutdown(wait=True) self._responsef = None self._responseexecutor = None # If any of our futures are still in progress, mark them as # errored, otherwise a result() could wait indefinitely. for f in self._futures: if not f.done(): f.set_exception(error.ResponseError( _('unfulfilled command response'))) self._futures = None def _handleresponse(self, handler, resp): # Called in a thread to read the response. while handler.readdata(resp): pass @interfaceutil.implementer(repository.ipeerv2) class httpv2peer(object): def __init__(self, ui, repourl, apipath, opener, requestbuilder, apidescriptor): self.ui = ui self.apidescriptor = apidescriptor if repourl.endswith('/'): repourl = repourl[:-1] self._url = repourl self._apipath = apipath self._apiurl = '%s/%s' % (repourl, apipath) self._opener = opener self._requestbuilder = requestbuilder self._redirect = wireprotov2peer.supportedredirects(ui, apidescriptor) # Start of ipeerconnection. def url(self): return self._url def local(self): return None def peer(self): return self def canpush(self): # TODO change once implemented. return False def close(self): self.ui.note(_('(sent %d HTTP requests and %d bytes; ' 'received %d bytes in responses)\n') % (self._opener.requestscount, self._opener.sentbytescount, self._opener.receivedbytescount)) # End of ipeerconnection. # Start of ipeercapabilities. def capable(self, name): # The capabilities used internally historically map to capabilities # advertised from the "capabilities" wire protocol command. However, # version 2 of that command works differently. # Maps to commands that are available. if name in ('branchmap', 'getbundle', 'known', 'lookup', 'pushkey'): return True # Other concepts. if name in ('bundle2'): return True # Alias command-* to presence of command of that name. if name.startswith('command-'): return name[len('command-'):] in self.apidescriptor['commands'] return False def requirecap(self, name, purpose): if self.capable(name): return raise error.CapabilityError( _('cannot %s; client or remote repository does not support the ' '\'%s\' capability') % (purpose, name)) # End of ipeercapabilities. def _call(self, name, **args): with self.commandexecutor() as e: return e.callcommand(name, args).result() def commandexecutor(self): return httpv2executor(self.ui, self._opener, self._requestbuilder, self._apiurl, self.apidescriptor, self._redirect) # Registry of API service names to metadata about peers that handle it. # # The following keys are meaningful: # # init # Callable receiving (ui, repourl, servicepath, opener, requestbuilder, # apidescriptor) to create a peer. # # priority # Integer priority for the service. If we could choose from multiple # services, we choose the one with the highest priority. API_PEERS = { wireprototypes.HTTP_WIREPROTO_V2: { 'init': httpv2peer, 'priority': 50, }, } def performhandshake(ui, url, opener, requestbuilder): # The handshake is a request to the capabilities command. caps = None def capable(x): raise error.ProgrammingError('should not be called') args = {} # The client advertises support for newer protocols by adding an # X-HgUpgrade-* header with a list of supported APIs and an # X-HgProto-* header advertising which serializing formats it supports. # We only support the HTTP version 2 transport and CBOR responses for # now. advertisev2 = ui.configbool('experimental', 'httppeer.advertise-v2') if advertisev2: args['headers'] = { r'X-HgProto-1': r'cbor', } args['headers'].update( encodevalueinheaders(' '.join(sorted(API_PEERS)), 'X-HgUpgrade', # We don't know the header limit this early. # So make it small. 1024)) req, requrl, qs = makev1commandrequest(ui, requestbuilder, caps, capable, url, 'capabilities', args) resp = sendrequest(ui, opener, req) # The server may redirect us to the repo root, stripping the # ?cmd=capabilities query string from the URL. The server would likely # return HTML in this case and ``parsev1commandresponse()`` would raise. # We catch this special case and re-issue the capabilities request against # the new URL. # # We should ideally not do this, as a redirect that drops the query # string from the URL is arguably a server bug. (Garbage in, garbage out). # However, Mercurial clients for several years appeared to handle this # issue without behavior degradation. And according to issue 5860, it may # be a longstanding bug in some server implementations. So we allow a # redirect that drops the query string to "just work." try: respurl, ct, resp = parsev1commandresponse(ui, url, requrl, qs, resp, compressible=False, allowcbor=advertisev2) except RedirectedRepoError as e: req, requrl, qs = makev1commandrequest(ui, requestbuilder, caps, capable, e.respurl, 'capabilities', args) resp = sendrequest(ui, opener, req) respurl, ct, resp = parsev1commandresponse(ui, url, requrl, qs, resp, compressible=False, allowcbor=advertisev2) try: rawdata = resp.read() finally: resp.close() if not ct.startswith('application/mercurial-'): raise error.ProgrammingError('unexpected content-type: %s' % ct) if advertisev2: if ct == 'application/mercurial-cbor': try: info = cborutil.decodeall(rawdata)[0] except cborutil.CBORDecodeError: raise error.Abort(_('error decoding CBOR from remote server'), hint=_('try again and consider contacting ' 'the server operator')) # We got a legacy response. That's fine. elif ct in ('application/mercurial-0.1', 'application/mercurial-0.2'): info = { 'v1capabilities': set(rawdata.split()) } else: raise error.RepoError( _('unexpected response type from server: %s') % ct) else: info = { 'v1capabilities': set(rawdata.split()) } return respurl, info def makepeer(ui, path, opener=None, requestbuilder=urlreq.request): """Construct an appropriate HTTP peer instance. ``opener`` is an ``url.opener`` that should be used to establish connections, perform HTTP requests. ``requestbuilder`` is the type used for constructing HTTP requests. It exists as an argument so extensions can override the default. """ u = util.url(path) if u.query or u.fragment: raise error.Abort(_('unsupported URL component: "%s"') % (u.query or u.fragment)) # urllib cannot handle URLs with embedded user or passwd. url, authinfo = u.authinfo() ui.debug('using %s\n' % url) opener = opener or urlmod.opener(ui, authinfo) respurl, info = performhandshake(ui, url, opener, requestbuilder) # Given the intersection of APIs that both we and the server support, # sort by their advertised priority and pick the first one. # # TODO consider making this request-based and interface driven. For # example, the caller could say "I want a peer that does X." It's quite # possible that not all peers would do that. Since we know the service # capabilities, we could filter out services not meeting the # requirements. Possibly by consulting the interfaces defined by the # peer type. apipeerchoices = set(info.get('apis', {}).keys()) & set(API_PEERS.keys()) preferredchoices = sorted(apipeerchoices, key=lambda x: API_PEERS[x]['priority'], reverse=True) for service in preferredchoices: apipath = '%s/%s' % (info['apibase'].rstrip('/'), service) return API_PEERS[service]['init'](ui, respurl, apipath, opener, requestbuilder, info['apis'][service]) # Failed to construct an API peer. Fall back to legacy. return httppeer(ui, path, respurl, opener, requestbuilder, info['v1capabilities']) def instance(ui, path, create, intents=None, createopts=None): if create: raise error.Abort(_('cannot create new http repository')) try: if path.startswith('https:') and not urlmod.has_https: raise error.Abort(_('Python support for SSL and HTTPS ' 'is not installed')) inst = makepeer(ui, path) return inst except error.RepoError as httpexception: try: r = statichttprepo.instance(ui, "static-" + path, create) ui.note(_('(falling back to static-http)\n')) return r except error.RepoError: raise httpexception # use the original http RepoError instead