view hgext/inotify/common.py @ 18520:751135cca13c stable

subrepo: allows to drop courtesy phase sync (issue3781)

Publishing server may contains draft changeset when they are created locally. As
publishing is the default, it is actually fairly common. Because of this
"inconsistency" phases synchronization may be done even to publishing server.

This may cause severe issues for subrepo. It is possible to reference read-only
repository as subrepo. Push in a super repo recursively push subrepo. Those
pushes to potential read only repo are not optional, they are "suffered" not
"choosed". This does not break because as the repo is untouched the push is
supposed to be empty. If the reference repo locally contains draft changesets, a
courtesy push is triggered to turn them public. As the repo is read only, the
push fails (after possible prompt asking for credential). Failure of the
sub-push aborts the whole subrepo push. This force the user to define a custom
default-push for such subrepo.

This changeset introduce a prevention of this error client side by skipping the
courtesy phase synchronisation in problematic situation. The phases
synchronisation is skipped when four conditions are gathered:
- this is a subrepo push, (normal push to read-only repo)
- and remote support phase
- and remote is publishing
- and no changesets was pushed (if we pushed changesets, repo is not read only)

The internal config option used in this version is not definitive. It is here to
demonstrate a working fix to the issue.

In the future we probably wants to track subrepo changes and avoid pushing to
untouched one. That will prevent any attempt to push to read-only or unreachable
subrepo.

Another fix to prevent courtesy push from older clients to push to newer server
is also still needed.

# server.py - inotify common protocol code
#
# Copyright 2006, 2007, 2008 Bryan O'Sullivan <[e-mail]>
# Copyright 2007, 2008 Brendan Cully <[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 cStringIO, socket, struct

"""
  Protocol between inotify clients and server:

  Client sending query:
  1) send protocol version number
  2) send query type (string, 4 letters long)
  3) send query parameters:
     - For STAT, N+1 \0-separated strings:
        1) N different names that need checking
        2) 1 string containing all the status types to match
     - No parameter needed for DBUG

  Server sending query answer:
  1) send protocol version number
  2) send query type
  3) send struct.pack'ed headers describing the length of the content:
      e.g. for STAT, receive 9 integers describing the length of the
      9 \0-separated string lists to be read:
       * one file list for each lmar!?ic status type
       * one list containing the directories visited during lookup

"""

version = 3

resphdrfmts = {
    'STAT': '>lllllllll', # status requests
    'DBUG': '>l'          # debugging queries
}
resphdrsizes = dict((k, struct.calcsize(v))
                    for k, v in resphdrfmts.iteritems())

def recvcs(sock):
    cs = cStringIO.StringIO()
    s = True
    try:
        while s:
            s = sock.recv(65536)
            cs.write(s)
    finally:
        sock.shutdown(socket.SHUT_RD)
    cs.seek(0)
    return cs