view tests/test-convert-svn-encoding.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 svn svn-bindings

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > convert =
  > EOF

  $ svnadmin create svn-repo
  $ svnadmin load -q svn-repo < "$TESTDIR/svn/encoding.svndump"

Convert while testing all possible outputs

  $ hg --debug convert svn-repo A-hg --config progress.debug=1
  initializing destination A-hg repository
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  run hg sink pre-conversion action
  scanning source...
  found trunk at 'trunk'
  found tags at 'tags'
  found branches at 'branches'
  found branch branch\xc3\xa9 at 5 (esc)
  found branch branch\xc3\xa9e at 6 (esc)
  scanning: 1/4 revisions (25.00%)
  reparent to file:/*/$TESTTMP/svn-repo/trunk (glob)
  fetching revision log for "/trunk" from 4 to 0
  parsing revision 4 (2 changes)
  parsing revision 3 (4 changes)
  parsing revision 2 (3 changes)
  parsing revision 1 (3 changes)
  no copyfrom path, don't know what to do.
  '/branches' is not under '/trunk', ignoring
  '/tags' is not under '/trunk', ignoring
  scanning: 2/4 revisions (50.00%)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9 (glob)
  fetching revision log for "/branches/branch\xc3\xa9" from 5 to 0 (esc)
  parsing revision 5 (1 changes)
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9 (glob)
  found parent of branch /branches/branch\xc3\xa9 at 4: /trunk (esc)
  scanning: 3/4 revisions (75.00%)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9e (glob)
  fetching revision log for "/branches/branch\xc3\xa9e" from 6 to 0 (esc)
  parsing revision 6 (1 changes)
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9e (glob)
  found parent of branch /branches/branch\xc3\xa9e at 5: /branches/branch\xc3\xa9 (esc)
  scanning: 4/4 revisions (100.00%)
  scanning: 5/4 revisions (125.00%)
  scanning: 6/4 revisions (150.00%)
  sorting...
  converting...
  5 init projA
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@1
  converting: 0/6 revisions (0.00%)
  committing changelog
  updating the branch cache
  4 hello
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@2
  converting: 1/6 revisions (16.67%)
  reparent to file:/*/$TESTTMP/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xa0 0/3 paths (0.00%) (esc)
  scanning paths: /trunk/\xc3\xa0/e\xcc\x81 1/3 paths (33.33%) (esc)
  scanning paths: /trunk/\xc3\xa9 2/3 paths (66.67%) (esc)
  committing files:
  \xc3\xa0/e\xcc\x81 (esc)
  getting files: \xc3\xa0/e\xcc\x81 1/2 files (50.00%) (esc)
  \xc3\xa9 (esc)
  getting files: \xc3\xa9 2/2 files (100.00%) (esc)
  committing manifest
  committing changelog
  updating the branch cache
  3 copy files
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@3
  converting: 2/6 revisions (33.33%)
  scanning paths: /trunk/\xc3\xa0 0/4 paths (0.00%) (esc)
  gone from -1
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xa8 1/4 paths (25.00%) (esc)
  copied to \xc3\xa8 from \xc3\xa9@2 (esc)
  scanning paths: /trunk/\xc3\xa9 2/4 paths (50.00%) (esc)
  gone from -1
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xb9 3/4 paths (75.00%) (esc)
  mark /trunk/\xc3\xb9 came from \xc3\xa0:2 (esc)
  getting files: \xc3\xa0/e\xcc\x81 1/4 files (25.00%) (esc)
  getting files: \xc3\xa9 2/4 files (50.00%) (esc)
  committing files:
  \xc3\xa8 (esc)
  getting files: \xc3\xa8 3/4 files (75.00%) (esc)
   \xc3\xa8: copy \xc3\xa9:6b67ccefd5ce6de77e7ead4f5292843a0255329f (esc)
  \xc3\xb9/e\xcc\x81 (esc)
  getting files: \xc3\xb9/e\xcc\x81 4/4 files (100.00%) (esc)
   \xc3\xb9/e\xcc\x81: copy \xc3\xa0/e\xcc\x81:a9092a3d84a37b9993b5c73576f6de29b7ea50f6 (esc)
  committing manifest
  committing changelog
  updating the branch cache
  2 remove files
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@4
  converting: 3/6 revisions (50.00%)
  scanning paths: /trunk/\xc3\xa8 0/2 paths (0.00%) (esc)
  gone from -1
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xb9 1/2 paths (50.00%) (esc)
  gone from -1
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/trunk (glob)
  getting files: \xc3\xa8 1/2 files (50.00%) (esc)
  getting files: \xc3\xb9/e\xcc\x81 2/2 files (100.00%) (esc)
  committing files:
  committing manifest
  committing changelog
  updating the branch cache
  1 branch to branch?
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/branches/branch?@5
  converting: 4/6 revisions (66.67%)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9 (glob)
  scanning paths: /branches/branch\xc3\xa9 0/1 paths (0.00%) (esc)
  committing changelog
  updating the branch cache
  0 branch to branch?e
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/branches/branch?e@6
  converting: 5/6 revisions (83.33%)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9e (glob)
  scanning paths: /branches/branch\xc3\xa9e 0/1 paths (0.00%) (esc)
  committing changelog
  updating the branch cache
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9e (glob)
  reparent to file:/*/$TESTTMP/svn-repo (glob)
  reparent to file:/*/$TESTTMP/svn-repo/branches/branch%C3%A9e (glob)
  updating tags
  committing files:
  .hgtags
  committing manifest
  committing changelog
  updating the branch cache
  run hg sink post-conversion action
  $ cd A-hg
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Check tags are in UTF-8

  $ cat .hgtags
  e94e4422020e715add80525e8f0f46c9968689f1 branch\xc3\xa9e (esc)
  f7e66f98380ed1e53a797c5c7a7a2616a7ab377d branch\xc3\xa9 (esc)

  $ cd ..