mercurial/sshpeer.py

largefiles: don't cache largefiles for pulled heads by default

After discussion, we've agreed that largefiles for newly pulled heads should
not be cached by default.  The use case for this is using largefiles repos
with multiple remote servers (and therefore multiple remote largefiles caches),
where users will be pulling from non-default locations on a regular basis.  We
think this use case will be significantly less common than the use case where
all largefiles are stored on the same central server, so the default should be
no caching.

The old behavior can be obtained by passing the --cache-largefiles flag to
pull.

# sshpeer.py - ssh repository proxy class for mercurial
#
# Copyright 2005, 2006 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import re
from i18n import _
import util, error, 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):
    '''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("'", "'\\''")

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, self.host, self.user, self.port)

        if create:
            cmd = '%s %s %s' % (sshcmd, args,
                util.shellquote("%s init %s" %
                    (_serverquote(remotecmd), _serverquote(self.path))))
            ui.note(_('running %s\n') % cmd)
            res = util.system(cmd)
            if res != 0:
                self._abort(error.RepoError(_("could not create remote repo")))

        self.validate_repo(ui, sshcmd, args, remotecmd)

    def url(self):
        return self._url

    def validate_repo(self, ui, 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))))
        ui.note(_('running %s\n') % cmd)
        cmd = util.quotecommand(cmd)
        self.pipeo, self.pipei, self.pipee = util.popen3(cmd)

        # 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:
                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):
        while True:
            size = util.fstat(self.pipee).st_size
            if size == 0:
                break
            s = self.pipee.read(size)
            if not s:
                break
            for l in s.splitlines():
                self.ui.status(_("remote: "), l, '\n')

    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 _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 _decompress(self, stream):
        return stream

    def _recv(self):
        l = self.pipei.readline()
        if l == '\n':
            err = []
            while True:
                line = self.pipee.readline()
                if line == '-\n':
                    break
                err.extend([line])
            if len(err) > 0:
                # strip the trailing newline added to the last line server-side
                err[-1] = err[-1][:-1]
            self._abort(error.OutOfBandError(*err))
        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