view tests/test-inherit-mode.t @ 37631:2f626233859b

wireproto: implement batching on peer executor interface

This is a bit more complicated than non-batch requests because we
need to buffer sends until the last request arrives *and* we need
to support resolving futures as data arrives from the remote.

In a classical concurrent.futures executor model, the future
"starts" as soon as it is submitted. However, we have nothing to
start until the last command is submitted.

If we did nothing, calling result() would deadlock, since the future
hasn't "started." So in the case where we queue the command, we return
a special future type whose result() will trigger sendcommands().
This eliminates the deadlock potential. It also serves as a check
against callers who may be calling result() prematurely, as it will
prevent any subsequent callcommands() from working. This behavior
is slightly annoying and a bit restrictive. But it's the world
that half duplex connections forces on us.

In order to support streaming responses, we were previously using
a generator. But with a futures-based API, we're using futures
and not generators. So in order to get streaming, we need a
background thread to read data from the server.

The approach taken in this patch is to leverage the ThreadPoolExecutor
from concurrent.futures for managing a background thread. We create
an executor and future that resolves when all response data is
processed (or an error occurs). When exiting the context manager,
we wait on that background reading before returning.

I was hoping we could manually spin up a threading.Thread and this
would be simple. But I ran into a few deadlocks when implementing.
After looking at the source code to concurrent.futures, I figured
it would just be easier to use a ThreadPoolExecutor than implement
all the code needed to manually manage a thread.

To prove this works, a use of the batch API in discovery has been
updated.

Differential Revision: https://phab.mercurial-scm.org/D3269

#require unix-permissions

test that new files created in .hg inherit the permissions from .hg/store

  $ mkdir dir

just in case somebody has a strange $TMPDIR

  $ chmod g-s dir
  $ cd dir

  $ cat >printmodes.py <<EOF
  > from __future__ import absolute_import, print_function
  > import os
  > import sys
  > 
  > allnames = []
  > isdir = {}
  > for root, dirs, files in os.walk(sys.argv[1]):
  >     for d in dirs:
  >         name = os.path.join(root, d)
  >         isdir[name] = 1
  >         allnames.append(name)
  >     for f in files:
  >         name = os.path.join(root, f)
  >         allnames.append(name)
  > allnames.sort()
  > for name in allnames:
  >     suffix = name in isdir and '/' or ''
  >     print('%05o %s%s' % (os.lstat(name).st_mode & 0o7777, name, suffix))
  > EOF

  $ cat >mode.py <<EOF
  > from __future__ import absolute_import, print_function
  > import os
  > import sys
  > print('%05o' % os.lstat(sys.argv[1]).st_mode)
  > EOF

  $ umask 077

  $ hg init repo
  $ cd repo

  $ chmod 0770 .hg/store

before commit
store can be written by the group, other files cannot
store is setgid

  $ $PYTHON ../printmodes.py .
  00700 ./.hg/
  00600 ./.hg/00changelog.i
  00600 ./.hg/requires
  00770 ./.hg/store/

  $ mkdir dir
  $ touch foo dir/bar
  $ hg ci -qAm 'add files'

after commit
working dir files can only be written by the owner
files created in .hg can be written by the group
(in particular, store/**, dirstate, branch cache file, undo files)
new directories are setgid

  $ $PYTHON ../printmodes.py .
  00700 ./.hg/
  00600 ./.hg/00changelog.i
  00770 ./.hg/cache/
  00660 ./.hg/cache/branch2-served
  00660 ./.hg/cache/rbc-names-v1
  00660 ./.hg/cache/rbc-revs-v1
  00660 ./.hg/dirstate
  00660 ./.hg/fsmonitor.state (fsmonitor !)
  00660 ./.hg/last-message.txt
  00600 ./.hg/requires
  00770 ./.hg/store/
  00660 ./.hg/store/00changelog.i
  00660 ./.hg/store/00manifest.i
  00770 ./.hg/store/data/
  00770 ./.hg/store/data/dir/
  00660 ./.hg/store/data/dir/bar.i (reporevlogstore !)
  00660 ./.hg/store/data/foo.i (reporevlogstore !)
  00770 ./.hg/store/data/dir/bar/ (reposimplestore !)
  00660 ./.hg/store/data/dir/bar/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
  00660 ./.hg/store/data/dir/bar/index (reposimplestore !)
  00770 ./.hg/store/data/foo/ (reposimplestore !)
  00660 ./.hg/store/data/foo/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
  00660 ./.hg/store/data/foo/index (reposimplestore !)
  00660 ./.hg/store/fncache (repofncache !)
  00660 ./.hg/store/phaseroots
  00660 ./.hg/store/undo
  00660 ./.hg/store/undo.backupfiles
  00660 ./.hg/store/undo.phaseroots
  00660 ./.hg/undo.backup.dirstate
  00660 ./.hg/undo.bookmarks
  00660 ./.hg/undo.branch
  00660 ./.hg/undo.desc
  00660 ./.hg/undo.dirstate
  00700 ./dir/
  00600 ./dir/bar
  00600 ./foo

  $ umask 007
  $ hg init ../push

before push
group can write everything

  $ $PYTHON ../printmodes.py ../push
  00770 ../push/.hg/
  00660 ../push/.hg/00changelog.i
  00660 ../push/.hg/requires
  00770 ../push/.hg/store/

  $ umask 077
  $ hg -q push ../push

after push
group can still write everything

  $ $PYTHON ../printmodes.py ../push
  00770 ../push/.hg/
  00660 ../push/.hg/00changelog.i
  00770 ../push/.hg/cache/
  00660 ../push/.hg/cache/branch2-base
  00660 ../push/.hg/dirstate
  00660 ../push/.hg/requires
  00770 ../push/.hg/store/
  00660 ../push/.hg/store/00changelog.i
  00660 ../push/.hg/store/00manifest.i
  00770 ../push/.hg/store/data/
  00770 ../push/.hg/store/data/dir/
  00660 ../push/.hg/store/data/dir/bar.i (reporevlogstore !)
  00660 ../push/.hg/store/data/foo.i (reporevlogstore !)
  00770 ../push/.hg/store/data/dir/bar/ (reposimplestore !)
  00660 ../push/.hg/store/data/dir/bar/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
  00660 ../push/.hg/store/data/dir/bar/index (reposimplestore !)
  00770 ../push/.hg/store/data/foo/ (reposimplestore !)
  00660 ../push/.hg/store/data/foo/b80de5d138758541c5f05265ad144ab9fa86d1db (reposimplestore !)
  00660 ../push/.hg/store/data/foo/index (reposimplestore !)
  00660 ../push/.hg/store/fncache (repofncache !)
  00660 ../push/.hg/store/undo
  00660 ../push/.hg/store/undo.backupfiles
  00660 ../push/.hg/store/undo.phaseroots
  00660 ../push/.hg/undo.bookmarks
  00660 ../push/.hg/undo.branch
  00660 ../push/.hg/undo.desc
  00660 ../push/.hg/undo.dirstate


Test that we don't lose the setgid bit when we call chmod.
Not all systems support setgid directories (e.g. HFS+), so
just check that directories have the same mode.

  $ cd ..
  $ hg init setgid
  $ cd setgid
  $ chmod g+rwx .hg/store
  $ chmod g+s .hg/store 2> /dev/null || true
  $ mkdir dir
  $ touch dir/file
  $ hg ci -qAm 'add dir/file'
  $ storemode=`$PYTHON ../mode.py .hg/store`
  $ dirmode=`$PYTHON ../mode.py .hg/store/data/dir`
  $ if [ "$storemode" != "$dirmode" ]; then
  >  echo "$storemode != $dirmode"
  > fi
  $ cd ..

  $ cd .. # g-s dir