Mercurial > hg
view mercurial/sshpeer.py @ 26644:74de1c59f71c
clonebundles: filter on bundle specification
Not all clients are capable of reading every bundle. Currently, content
negotiation to ensure a server sends a client a compatible bundle
format is performed at request time. The response bundle is dynamically
generated at request time, so this works fine.
Clone bundles are statically generated *before* the request. This means
that a modern server could produce bundles that a legacy client isn't
capable of reading. Without some kind of "type hint" in the clone
bundles manifest, a client may attempt to download an incompatible
bundle. Furthermore, a client may not realize a bundle is incompatible
until it has processed part of the bundle (imagine consuming a 1 GB
changegroup bundle2 part only to discover the bundle2 part afterwards is
incompatibl). This would waste time and resources. And it isn't very
user friendly.
Clone bundle manifests thus need to advertise the *exact* format of the
hosted bundles so clients may filter out entries that they don't know
how to read. This patch introduces that mechanism.
We introduce the BUNDLESPEC attribute to declare the "bundle
specification" of the entry. Bundle specifications are parsed using
exchange.parsebundlespecification, which uses the same strings as the
"--type" argument to `hg bundle`. The supported bundle specifications
are well defined and backwards compatible.
When a client encounters a BUNDLESPEC that is invalid or unsupported, it
silently ignores the entry.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Tue, 13 Oct 2015 11:45:30 -0700 |
parents | 56b2bcea2529 |
children | 1aee2ab0f902 |
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# sshpeer.py - ssh repository proxy class 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 re from .i18n import _ from . import ( error, util, wireproto, ) class remotelock(object): def __init__(self, repo): self.repo = repo def release(self): self.repo.unlock() self.repo = None def __del__(self): if self.repo: self.release() def _serverquote(s): if not s: return s '''quote a string for the remote shell ... which we assume is sh''' if re.match('[a-zA-Z0-9@%_+=:,./-]*$', s): return s return "'%s'" % s.replace("'", "'\\''") def _forwardoutput(ui, pipe): """display all data currently available on pipe as remote output. This is non blocking.""" s = util.readpipe(pipe) if s: for l in s.splitlines(): ui.status(_("remote: "), l, '\n') class doublepipe(object): """Operate a side-channel pipe in addition of a main one The side-channel pipe contains server output to be forwarded to the user input. The double pipe will behave as the "main" pipe, but will ensure the content of the "side" pipe is properly processed while we wait for blocking call on the "main" pipe. If large amounts of data are read from "main", the forward will cease after the first bytes start to appear. This simplifies the implementation without affecting actual output of sshpeer too much as we rarely issue large read for data not yet emitted by the server. The main pipe is expected to be a 'bufferedinputpipe' from the util module that handle all the os specific bites. This class lives in this module because it focus on behavior specifig to the ssh protocol.""" def __init__(self, ui, main, side): self._ui = ui self._main = main self._side = side def _wait(self): """wait until some data are available on main or side return a pair of boolean (ismainready, issideready) (This will only wait for data if the setup is supported by `util.poll`) """ if getattr(self._main, 'hasbuffer', False): # getattr for classic pipe return (True, True) # main has data, assume side is worth poking at. fds = [self._main.fileno(), self._side.fileno()] try: act = util.poll(fds) except NotImplementedError: # non supported yet case, assume all have data. act = fds return (self._main.fileno() in act, self._side.fileno() in act) def write(self, data): return self._call('write', data) def read(self, size): return self._call('read', size) def readline(self): return self._call('readline') def _call(self, methname, data=None): """call <methname> on "main", forward output of "side" while blocking """ # data can be '' or 0 if (data is not None and not data) or self._main.closed: _forwardoutput(self._ui, self._side) return '' while True: mainready, sideready = self._wait() if sideready: _forwardoutput(self._ui, self._side) if mainready: meth = getattr(self._main, methname) if data is None: return meth() else: return meth(data) def close(self): return self._main.close() def flush(self): return self._main.flush() class sshpeer(wireproto.wirepeer): def __init__(self, ui, path, create=False): self._url = path self.ui = ui self.pipeo = self.pipei = self.pipee = None u = util.url(path, parsequery=False, parsefragment=False) if u.scheme != 'ssh' or not u.host or u.path is None: self._abort(error.RepoError(_("couldn't parse location %s") % path)) self.user = u.user if u.passwd is not None: self._abort(error.RepoError(_("password in URL not supported"))) self.host = u.host self.port = u.port self.path = u.path or "." sshcmd = self.ui.config("ui", "ssh", "ssh") remotecmd = self.ui.config("ui", "remotecmd", "hg") args = util.sshargs(sshcmd, _serverquote(self.host), _serverquote(self.user), _serverquote(self.port)) if create: cmd = '%s %s %s' % (sshcmd, args, util.shellquote("%s init %s" % (_serverquote(remotecmd), _serverquote(self.path)))) ui.debug('running %s\n' % cmd) res = ui.system(cmd) if res != 0: self._abort(error.RepoError(_("could not create remote repo"))) self._validaterepo(sshcmd, args, remotecmd) def url(self): return self._url def _validaterepo(self, sshcmd, args, remotecmd): # cleanup up previous run self.cleanup() cmd = '%s %s %s' % (sshcmd, args, util.shellquote("%s -R %s serve --stdio" % (_serverquote(remotecmd), _serverquote(self.path)))) self.ui.debug('running %s\n' % cmd) cmd = util.quotecommand(cmd) # while self.subprocess isn't used, having it allows the subprocess to # to clean up correctly later # # no buffer allow the use of 'select' # feel free to remove buffering and select usage when we ultimately # move to threading. sub = util.popen4(cmd, bufsize=0) self.pipeo, self.pipei, self.pipee, self.subprocess = sub self.pipei = util.bufferedinputpipe(self.pipei) self.pipei = doublepipe(self.ui, self.pipei, self.pipee) self.pipeo = doublepipe(self.ui, self.pipeo, self.pipee) # skip any noise generated by remote shell self._callstream("hello") r = self._callstream("between", pairs=("%s-%s" % ("0"*40, "0"*40))) lines = ["", "dummy"] max_noise = 500 while lines[-1] and max_noise: l = r.readline() self.readerr() if lines[-1] == "1\n" and l == "\n": break if l: self.ui.debug("remote: ", l) lines.append(l) max_noise -= 1 else: self._abort(error.RepoError(_('no suitable response from ' 'remote hg'))) self._caps = set() for l in reversed(lines): if l.startswith("capabilities:"): self._caps.update(l[:-1].split(":")[1].split()) break def _capabilities(self): return self._caps def readerr(self): _forwardoutput(self.ui, self.pipee) def _abort(self, exception): self.cleanup() raise exception def cleanup(self): if self.pipeo is None: return self.pipeo.close() self.pipei.close() try: # read the error descriptor until EOF for l in self.pipee: self.ui.status(_("remote: "), l) except (IOError, ValueError): pass self.pipee.close() __del__ = cleanup def _callstream(self, cmd, **args): self.ui.debug("sending %s command\n" % cmd) self.pipeo.write("%s\n" % cmd) _func, names = wireproto.commands[cmd] keys = names.split() wireargs = {} for k in keys: if k == '*': wireargs['*'] = args break else: wireargs[k] = args[k] del args[k] for k, v in sorted(wireargs.iteritems()): self.pipeo.write("%s %d\n" % (k, len(v))) if isinstance(v, dict): for dk, dv in v.iteritems(): self.pipeo.write("%s %d\n" % (dk, len(dv))) self.pipeo.write(dv) else: self.pipeo.write(v) self.pipeo.flush() return self.pipei def _callcompressable(self, cmd, **args): return self._callstream(cmd, **args) def _call(self, cmd, **args): self._callstream(cmd, **args) return self._recv() def _callpush(self, cmd, fp, **args): r = self._call(cmd, **args) if r: return '', r while True: d = fp.read(4096) if not d: break self._send(d) self._send("", flush=True) r = self._recv() if r: return '', r return self._recv(), '' def _calltwowaystream(self, cmd, fp, **args): r = self._call(cmd, **args) if r: # XXX needs to be made better raise error.Abort('unexpected remote reply: %s' % r) while True: d = fp.read(4096) if not d: break self._send(d) self._send("", flush=True) return self.pipei def _recv(self): l = self.pipei.readline() if l == '\n': self.readerr() msg = _('check previous remote output') self._abort(error.OutOfBandError(hint=msg)) self.readerr() try: l = int(l) except ValueError: self._abort(error.ResponseError(_("unexpected response:"), l)) return self.pipei.read(l) def _send(self, data, flush=False): self.pipeo.write("%d\n" % len(data)) if data: self.pipeo.write(data) if flush: self.pipeo.flush() self.readerr() def lock(self): self._call("lock") return remotelock(self) def unlock(self): self._call("unlock") def addchangegroup(self, cg, source, url, lock=None): '''Send a changegroup to the remote server. Return an integer similar to unbundle(). DEPRECATED, since it requires locking the remote.''' d = self._call("addchangegroup") if d: self._abort(error.RepoError(_("push refused: %s") % d)) while True: d = cg.read(4096) if not d: break self.pipeo.write(d) self.readerr() self.pipeo.flush() self.readerr() r = self._recv() if not r: return 1 try: return int(r) except ValueError: self._abort(error.ResponseError(_("unexpected response:"), r)) instance = sshpeer