tests/badserverext.py
author Jun Wu <quark@fb.com>
Wed, 06 Sep 2017 16:13:04 -0700
changeset 34109 5d45a997d11d
parent 33196 c077eac329e2
child 36425 fb7897e53d49
permissions -rw-r--r--
rebase: remove complex unhiding code This is similar to Martin von Zweigbergk's previous patch [1]. Previous patches are adding more `.unfiltered()` to the rebase code. So I wonder: are we playing whack-a-mole regarding on `unfiltered()` in rebase? Thinking about it, I believe most of the rebase code *should* just use an unfiltered repo. The only exception is before we figuring out a `rebasestate`. This patch makes it so. See added comment in code for why that's more reasonable. This would make the code base cleaner (not mangling the `repo` object), faster (no need to invalidate caches), simpler (less LOC), less error-prone (no need to think about what to unhide, ex. should we unhide wdir p2? how about destinations?), and future proof (other code may change visibility in an unexpected way, ex. directaccess may make the destination only visible when it's in "--dest" revset tree). [1]: https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-March/094277.html Differential Revision: https://phab.mercurial-scm.org/D644

# badserverext.py - Extension making servers behave badly
#
# Copyright 2017 Gregory Szorc <gregory.szorc@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.

# no-check-code

"""Extension to make servers behave badly.

This extension is useful for testing Mercurial behavior when various network
events occur.

Various config options in the [badserver] section influence behavior:

closebeforeaccept
   If true, close() the server socket when a new connection arrives before
   accept() is called. The server will then exit.

closeafteraccept
   If true, the server will close() the client socket immediately after
   accept().

closeafterrecvbytes
   If defined, close the client socket after receiving this many bytes.

closeaftersendbytes
   If defined, close the client socket after sending this many bytes.
"""

from __future__ import absolute_import

import socket

from mercurial import(
    registrar,
)

from mercurial.hgweb import (
    server,
)

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

configitem('badserver', 'closeafteraccept',
    default=False,
)
configitem('badserver', 'closeafterrecvbytes',
    default=0,
)
configitem('badserver', 'closeaftersendbytes',
    default=0,
)
configitem('badserver', 'closebeforeaccept',
    default=False,
)

# We can't adjust __class__ on a socket instance. So we define a proxy type.
class socketproxy(object):
    __slots__ = (
        '_orig',
        '_logfp',
        '_closeafterrecvbytes',
        '_closeaftersendbytes',
    )

    def __init__(self, obj, logfp, closeafterrecvbytes=0,
                 closeaftersendbytes=0):
        object.__setattr__(self, '_orig', obj)
        object.__setattr__(self, '_logfp', logfp)
        object.__setattr__(self, '_closeafterrecvbytes', closeafterrecvbytes)
        object.__setattr__(self, '_closeaftersendbytes', closeaftersendbytes)

    def __getattribute__(self, name):
        if name in ('makefile',):
            return object.__getattribute__(self, name)

        return getattr(object.__getattribute__(self, '_orig'), name)

    def __delattr__(self, name):
        delattr(object.__getattribute__(self, '_orig'), name)

    def __setattr__(self, name, value):
        setattr(object.__getattribute__(self, '_orig'), name, value)

    def makefile(self, mode, bufsize):
        f = object.__getattribute__(self, '_orig').makefile(mode, bufsize)

        logfp = object.__getattribute__(self, '_logfp')
        closeafterrecvbytes = object.__getattribute__(self,
                                                      '_closeafterrecvbytes')
        closeaftersendbytes = object.__getattribute__(self,
                                                      '_closeaftersendbytes')

        return fileobjectproxy(f, logfp,
                               closeafterrecvbytes=closeafterrecvbytes,
                               closeaftersendbytes=closeaftersendbytes)

# We can't adjust __class__ on socket._fileobject, so define a proxy.
class fileobjectproxy(object):
    __slots__ = (
        '_orig',
        '_logfp',
        '_closeafterrecvbytes',
        '_closeaftersendbytes',
    )

    def __init__(self, obj, logfp, closeafterrecvbytes=0,
                 closeaftersendbytes=0):
        object.__setattr__(self, '_orig', obj)
        object.__setattr__(self, '_logfp', logfp)
        object.__setattr__(self, '_closeafterrecvbytes', closeafterrecvbytes)
        object.__setattr__(self, '_closeaftersendbytes', closeaftersendbytes)

    def __getattribute__(self, name):
        if name in ('read', 'readline', 'write', '_writelog'):
            return object.__getattribute__(self, name)

        return getattr(object.__getattribute__(self, '_orig'), name)

    def __delattr__(self, name):
        delattr(object.__getattribute__(self, '_orig'), name)

    def __setattr__(self, name, value):
        setattr(object.__getattribute__(self, '_orig'), name, value)

    def _writelog(self, msg):
        msg = msg.replace('\r', '\\r').replace('\n', '\\n')

        object.__getattribute__(self, '_logfp').write(msg)
        object.__getattribute__(self, '_logfp').write('\n')
        object.__getattribute__(self, '_logfp').flush()

    def read(self, size=-1):
        remaining = object.__getattribute__(self, '_closeafterrecvbytes')

        # No read limit. Call original function.
        if not remaining:
            result = object.__getattribute__(self, '_orig').read(size)
            self._writelog('read(%d) -> (%d) (%s) %s' % (size,
                                                           len(result),
                                                           result))
            return result

        origsize = size

        if size < 0:
            size = remaining
        else:
            size = min(remaining, size)

        result = object.__getattribute__(self, '_orig').read(size)
        remaining -= len(result)

        self._writelog('read(%d from %d) -> (%d) %s' % (
            size, origsize, len(result), result))

        object.__setattr__(self, '_closeafterrecvbytes', remaining)

        if remaining <= 0:
            self._writelog('read limit reached, closing socket')
            self._sock.close()
            # This is the easiest way to abort the current request.
            raise Exception('connection closed after receiving N bytes')

        return result

    def readline(self, size=-1):
        remaining = object.__getattribute__(self, '_closeafterrecvbytes')

        # No read limit. Call original function.
        if not remaining:
            result = object.__getattribute__(self, '_orig').readline(size)
            self._writelog('readline(%d) -> (%d) %s' % (
                size, len(result), result))
            return result

        origsize = size

        if size < 0:
            size = remaining
        else:
            size = min(remaining, size)

        result = object.__getattribute__(self, '_orig').readline(size)
        remaining -= len(result)

        self._writelog('readline(%d from %d) -> (%d) %s' % (
            size, origsize, len(result), result))

        object.__setattr__(self, '_closeafterrecvbytes', remaining)

        if remaining <= 0:
            self._writelog('read limit reached; closing socket')
            self._sock.close()
            # This is the easiest way to abort the current request.
            raise Exception('connection closed after receiving N bytes')

        return result

    def write(self, data):
        remaining = object.__getattribute__(self, '_closeaftersendbytes')

        # No byte limit on this operation. Call original function.
        if not remaining:
            self._writelog('write(%d) -> %s' % (len(data), data))
            result = object.__getattribute__(self, '_orig').write(data)
            return result

        if len(data) > remaining:
            newdata = data[0:remaining]
        else:
            newdata = data

        remaining -= len(newdata)

        self._writelog('write(%d from %d) -> (%d) %s' % (
            len(newdata), len(data), remaining, newdata))

        result = object.__getattribute__(self, '_orig').write(newdata)

        object.__setattr__(self, '_closeaftersendbytes', remaining)

        if remaining <= 0:
            self._writelog('write limit reached; closing socket')
            self._sock.close()
            raise Exception('connection closed after sending N bytes')

        return result

def extsetup(ui):
    # Change the base HTTP server class so various events can be performed.
    # See SocketServer.BaseServer for how the specially named methods work.
    class badserver(server.MercurialHTTPServer):
        def __init__(self, ui, *args, **kwargs):
            self._ui = ui
            super(badserver, self).__init__(ui, *args, **kwargs)

            # Need to inherit object so super() works.
            class badrequesthandler(self.RequestHandlerClass, object):
                def send_header(self, name, value):
                    # Make headers deterministic to facilitate testing.
                    if name.lower() == 'date':
                        value = 'Fri, 14 Apr 2017 00:00:00 GMT'
                    elif name.lower() == 'server':
                        value = 'badhttpserver'

                    return super(badrequesthandler, self).send_header(name,
                                                                      value)

            self.RequestHandlerClass = badrequesthandler

        # Called to accept() a pending socket.
        def get_request(self):
            if self._ui.configbool('badserver', 'closebeforeaccept'):
                self.socket.close()

                # Tells the server to stop processing more requests.
                self.__shutdown_request = True

                # Simulate failure to stop processing this request.
                raise socket.error('close before accept')

            if self._ui.configbool('badserver', 'closeafteraccept'):
                request, client_address = super(badserver, self).get_request()
                request.close()
                raise socket.error('close after accept')

            return super(badserver, self).get_request()

        # Does heavy lifting of processing a request. Invokes
        # self.finish_request() which calls self.RequestHandlerClass() which
        # is a hgweb.server._httprequesthandler.
        def process_request(self, socket, address):
            # Wrap socket in a proxy if we need to count bytes.
            closeafterrecvbytes = self._ui.configint('badserver',
                                                     'closeafterrecvbytes')
            closeaftersendbytes = self._ui.configint('badserver',
                                                     'closeaftersendbytes')

            if closeafterrecvbytes or closeaftersendbytes:
                socket = socketproxy(socket, self.errorlog,
                                     closeafterrecvbytes=closeafterrecvbytes,
                                     closeaftersendbytes=closeaftersendbytes)

            return super(badserver, self).process_request(socket, address)

    server.MercurialHTTPServer = badserver