view tests/sshprotoext.py @ 40924:08cfa77d7288

wireprotov2: unify file revision collection and linknode derivation

The old mechanism for choosing which file revisions to send in the
haveparents=True case was buggy in multiple ways - the most severe
of which being that file revisions were excluded when they shouldn't
have been.

This commit unifies the logic for deriving the filenodes that will
be sent by the "filesdata" command. We now consistently read files
data from manifests. The "haveparents" argument now controls whether
we iterate ctx.files() or use the full manifest to derive relevant
files.

The logic here is still woefully lacking to fully support shallow
clones. It will require an API break to fully address. This commit
should at least make the server APIs emit proper data, which is
strictly better than before.

Differential Revision: https://phab.mercurial-scm.org/D5406

# sshprotoext.py - Extension to test behavior of SSH protocol
#
# Copyright 2018 Gregory Szorc <[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.

# This extension replaces the SSH server started via `hg serve --stdio`.
# The server behaves differently depending on environment variables.

from __future__ import absolute_import

from mercurial import (
    error,
    extensions,
    registrar,
    sshpeer,
    wireprotoserver,
    wireprotov1server,
)

configtable = {}
configitem = registrar.configitem(configtable)

configitem(b'sshpeer', b'mode', default=None)
configitem(b'sshpeer', b'handshake-mode', default=None)

class bannerserver(wireprotoserver.sshserver):
    """Server that sends a banner to stdout."""
    def serve_forever(self):
        for i in range(10):
            self._fout.write(b'banner: line %d\n' % i)

        super(bannerserver, self).serve_forever()

class prehelloserver(wireprotoserver.sshserver):
    """Tests behavior when connecting to <0.9.1 servers.

    The ``hello`` wire protocol command was introduced in Mercurial
    0.9.1. Modern clients send the ``hello`` command when connecting
    to SSH servers. This mock server tests behavior of the handshake
    when ``hello`` is not supported.
    """
    def serve_forever(self):
        l = self._fin.readline()
        assert l == b'hello\n'
        # Respond to unknown commands with an empty reply.
        wireprotoserver._sshv1respondbytes(self._fout, b'')
        l = self._fin.readline()
        assert l == b'between\n'
        proto = wireprotoserver.sshv1protocolhandler(self._ui, self._fin,
                                                     self._fout)
        rsp = wireprotov1server.dispatch(self._repo, proto, b'between')
        wireprotoserver._sshv1respondbytes(self._fout, rsp.data)

        super(prehelloserver, self).serve_forever()

def performhandshake(orig, ui, stdin, stdout, stderr):
    """Wrapped version of sshpeer._performhandshake to send extra commands."""
    mode = ui.config(b'sshpeer', b'handshake-mode')
    if mode == b'pre-no-args':
        ui.debug(b'sending no-args command\n')
        stdin.write(b'no-args\n')
        stdin.flush()
        return orig(ui, stdin, stdout, stderr)
    elif mode == b'pre-multiple-no-args':
        ui.debug(b'sending unknown1 command\n')
        stdin.write(b'unknown1\n')
        ui.debug(b'sending unknown2 command\n')
        stdin.write(b'unknown2\n')
        ui.debug(b'sending unknown3 command\n')
        stdin.write(b'unknown3\n')
        stdin.flush()
        return orig(ui, stdin, stdout, stderr)
    else:
        raise error.ProgrammingError(b'unknown HANDSHAKECOMMANDMODE: %s' %
                                     mode)

def extsetup(ui):
    # It's easier for tests to define the server behavior via environment
    # variables than config options. This is because `hg serve --stdio`
    # has to be invoked with a certain form for security reasons and
    # `dummyssh` can't just add `--config` flags to the command line.
    servermode = ui.environ.get(b'SSHSERVERMODE')

    if servermode == b'banner':
        wireprotoserver.sshserver = bannerserver
    elif servermode == b'no-hello':
        wireprotoserver.sshserver = prehelloserver
    elif servermode:
        raise error.ProgrammingError(b'unknown server mode: %s' % servermode)

    peermode = ui.config(b'sshpeer', b'mode')

    if peermode == b'extra-handshake-commands':
        extensions.wrapfunction(sshpeer, '_performhandshake', performhandshake)
    elif peermode:
        raise error.ProgrammingError(b'unknown peer mode: %s' % peermode)