Mercurial > hg
view mercurial/httppeer.py @ 39750:ec723284d07a
bookmarks: parse out implicit "add" action early
This prepares for adding -l/--list option, which can be combined with the
positional arguments.
author | Yuya Nishihara <yuya@tcha.org> |
---|---|
date | Sat, 15 Sep 2018 12:25:19 +0900 |
parents | 9c2c77c73f23 |
children | f80db6adabbe |
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 def _wraphttpresponse(resp): """Wrap an HTTPResponse with common error handlers. This ensures that any I/O from any consumer raises the appropriate error and messaging. """ origread = resp.read class readerproxy(resp.__class__): def read(self, size=None): try: return origread(size) except httplib.IncompleteRead as e: # e.expected is an integer if length known or None otherwise. if e.expected: got = len(e.partial) total = e.expected + got msg = _('HTTP request error (incomplete response; ' 'expected %d bytes got %d)') % (total, got) else: msg = _('HTTP request error (incomplete response)') raise error.PeerTransportError( msg, hint=_('this may be an intermittent network failure; ' 'if the error persists, consider contacting the ' 'network or server operator')) except httplib.HTTPException as e: raise error.PeerTransportError( _('HTTP request error (%s)') % e, hint=_('this may be an intermittent network failure; ' 'if the error persists, consider contacting the ' 'network or server operator')) resp.__class__ = readerproxy 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. _wraphttpresponse(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): pass # 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): reactor = wireprotoframing.clientreactor(hasmultiplesend=False, buffersends=True) handler = wireprotov2peer.clienthandler(ui, reactor) 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)) # 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): self._ui = ui self._opener = opener self._requestbuilder = requestbuilder self._apiurl = apiurl self._descriptor = descriptor 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) # 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.readframe(resp): pass # TODO implement interface for version 2 peers @interfaceutil.implementer(repository.ipeerconnection, repository.ipeercapabilities, repository.ipeerrequests) class httpv2peer(object): def __init__(self, ui, repourl, apipath, opener, requestbuilder, apidescriptor): self.ui = ui 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._descriptor = 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): pass # 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._descriptor['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 %r ' '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._descriptor) # 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