view tests/test-narrow-exchange.t @ 36367:043e77f3be09

sshpeer: return framed file object when needed

Currently, wireproto.wirepeer has a default implementation of
_submitbatch() and sshv1peer has a very similar implementation.
The main difference is that sshv1peer is aware of the total amount
of bytes it can read whereas the default implementation reads the
stream until no more data is returned. The default implementation
works for HTTP, since there is a known end to HTTP responses (either
Content-Length or 0 sized chunk).

This commit teaches sshv1peer to use our just-introduced "cappedreader"
class for wrapping a file object to limit the number of bytes that
can be read. We do this by introducing an argument to specify whether
the response is framed. If set, we returned a cappedreader instance
instead of the raw pipe.

_call() always has framed responses. So we set this argument
unconditionally and then .read() the entirety of the result.
Strictly speaking, we don't need to use cappedreader in this case
and can inline frame decoding/read logic. But I like when things
are consistent. The overhead should be negligible.

_callstream() and _callcompressable() are special: whether framing
is used depends on the specific command. So, we define a set
of commands that have framed response. It currently only
contains "batch."

As a result of this change, the one-off implementation of
_submitbatch() in sshv1peer can be removed since it is now
safe to .read() the response's file object until end of stream.
cappedreader takes care of not overrunning the frame.

Differential Revision: https://phab.mercurial-scm.org/D2380

  $ . "$TESTDIR/narrow-library.sh"

create full repo

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [narrow]
  > serveellipses=True
  > EOF

  $ mkdir inside
  $ echo 1 > inside/f
  $ mkdir inside2
  $ echo 1 > inside2/f
  $ mkdir outside
  $ echo 1 > outside/f
  $ hg ci -Aqm 'initial'

  $ echo 2 > inside/f
  $ hg ci -qm 'inside 2'

  $ echo 2 > inside2/f
  $ hg ci -qm 'inside2 2'

  $ echo 2 > outside/f
  $ hg ci -qm 'outside 2'

  $ cd ..

  $ hg clone --narrow ssh://user@dummy/master narrow --include inside
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 2 changes to 1 files
  new changesets *:* (glob)
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg clone --narrow ssh://user@dummy/master narrow2 --include inside --include inside2
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 4 changesets with 4 changes to 2 files
  new changesets *:* (glob)
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

Can push to wider repo if change does not affect paths in wider repo that are
not also in narrower repo

  $ cd narrow
  $ echo 3 > inside/f
  $ hg ci -m 'inside 3'
  $ hg push ssh://user@dummy/narrow2
  pushing to ssh://user@dummy/narrow2
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files

Can push to narrower repo if change affects only paths within remote's
narrow spec

  $ cd ../narrow2
  $ cat >> .hg/hgrc <<EOF
  > [narrow]
  > serveellipses=True
  > EOF
  $ hg co -r 'desc("inside 3")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo 4 > inside/f
  $ hg ci -m 'inside 4'
  $ hg push ssh://user@dummy/narrow
  pushing to ssh://user@dummy/narrow
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files

Can push to narrow repo if change affects only paths outside remote's
narrow spec

  $ echo 3 > inside2/f
  $ hg ci -m 'inside2 3'
TODO: this should be successful
  $ hg push ssh://user@dummy/narrow
  pushing to ssh://user@dummy/narrow
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: transaction abort!
  remote: rollback completed
  remote: abort: data/inside2/f.i@4a1aa07735e6: unknown parent!
  abort: stream ended unexpectedly (got 0 bytes, expected 4)
  [255]

Can pull from wider repo if change affects only paths outside remote's
narrow spec
  $ echo 4 > inside2/f
  $ hg ci -m 'inside2 4'
  $ hg log -G -T '{rev} {node|short} {files}\n'
  @  7 d78a96df731d inside2/f
  |
  o  6 8c26f5218962 inside2/f
  |
  o  5 ba3480e2f9de inside/f
  |
  o  4 4e5edd526618 inside/f
  |
  o  3 81e7e07b7ab0 outside/f
  |
  o  2 f3993b8c0c2b inside2/f
  |
  o  1 8cd66ca966b4 inside/f
  |
  o  0 c8057d6f53ab inside/f inside2/f outside/f
  
  $ cd ../narrow
  $ hg log -G -T '{rev} {node|short} {files}\n'
  o  4 ba3480e2f9de inside/f
  |
  @  3 4e5edd526618 inside/f
  |
  o  2 81e7e07b7ab0 outside/f
  |
  o  1 8cd66ca966b4 inside/f
  |
  o  0 c8057d6f53ab inside/f inside2/f outside/f
  
  $ hg pull ssh://user@dummy/narrow2
  pulling from ssh://user@dummy/narrow2
  searching for changes
  remote: abort: unable to resolve parent while packing 'data/inside2/f.i' 3 for changeset 5 (?)
  adding changesets
  remote: abort: unexpected error: unable to resolve parent while packing 'data/inside2/f.i' 3 for changeset 5
  transaction abort!
  rollback completed
  abort: pull failed on remote
  [255]

Check that the resulting history is valid in the full repo

  $ cd ../narrow2
  $ hg push ssh://user@dummy/master
  pushing to ssh://user@dummy/master
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 4 changesets with 4 changes to 2 files
  $ cd ../master
  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  3 files, 8 changesets, 10 total revisions

Can not push to wider repo if change affects paths in wider repo that are
not also in narrower repo
  $ cd ../master
  $ hg co -r 'desc("inside2 4")'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo 5 > inside2/f
  $ hg ci -m 'inside2 5'
  $ hg log -G -T '{rev} {node|short} {files}\n'
  @  8 5970befb64ba inside2/f
  |
  o  7 d78a96df731d inside2/f
  |
  o  6 8c26f5218962 inside2/f
  |
  o  5 ba3480e2f9de inside/f
  |
  o  4 4e5edd526618 inside/f
  |
  o  3 81e7e07b7ab0 outside/f
  |
  o  2 f3993b8c0c2b inside2/f
  |
  o  1 8cd66ca966b4 inside/f
  |
  o  0 c8057d6f53ab inside/f inside2/f outside/f
  
  $ cd ../narrow
  $ hg pull
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files
  new changesets * (glob)
  (run 'hg update' to get a working copy)
TODO: this should tell the user that their narrow clone does not have the
necessary content to be able to push to the target
  $ hg push ssh://user@dummy/narrow2
  pushing to ssh://user@dummy/narrow2
  searching for changes
  remote has heads on branch 'default' that are not known locally: d78a96df731d
  abort: push creates new remote head 5970befb64ba!
  (pull and merge or see 'hg help push' for details about pushing new heads)
  [255]