Mercurial > hg
view tests/test-issue3084.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
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Fri, 13 Apr 2018 11:02:34 -0700 |
parents | 9d5c27890790 |
children |
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$ echo "[extensions]" >> $HGRCPATH $ echo "largefiles =" >> $HGRCPATH Create the repository outside $HOME since largefiles write to $HOME/.cache/largefiles. $ hg init test $ cd test $ echo "root" > root $ hg add root $ hg commit -m "Root commit" --config extensions.largefiles=! Ensure that .hg/largefiles isn't created before largefiles are added #if unix-permissions $ chmod 555 .hg #endif $ hg status #if unix-permissions $ chmod 755 .hg #endif $ test -f .hg/largefiles [1] $ echo "large" > foo $ hg add --large foo $ hg commit -m "Add foo as a largefile" $ hg update -r 0 getting changed largefiles 0 largefiles updated, 1 removed 0 files updated, 0 files merged, 1 files removed, 0 files unresolved $ echo "normal" > foo $ hg add foo $ hg commit -m "Add foo as normal file" created new head Normal file in the working copy, keeping the normal version: $ echo "n" | hg merge --config ui.interactive=Yes remote turned local normal file foo into a largefile use (l)argefile or keep (n)ormal file? n 0 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg status $ cat foo normal Normal file in the working copy, keeping the largefile version: $ hg update -q -C $ echo "l" | hg merge --config ui.interactive=Yes remote turned local normal file foo into a largefile use (l)argefile or keep (n)ormal file? l getting changed largefiles 1 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg status M foo $ hg diff --nodates diff -r fa129ab6b5a7 .hglf/foo --- /dev/null +++ b/.hglf/foo @@ -0,0 +1,1 @@ +7f7097b041ccf68cc5561e9600da4655d21c6d18 diff -r fa129ab6b5a7 foo --- a/foo +++ /dev/null @@ -1,1 +0,0 @@ -normal $ cat foo large Largefile in the working copy, keeping the normal version: $ hg update -q -C -r 1 $ echo "n" | hg merge --config ui.interactive=Yes remote turned local largefile foo into a normal file keep (l)argefile or use (n)ormal file? n getting changed largefiles 0 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg status M foo $ hg diff --nodates diff -r ff521236428a .hglf/foo --- a/.hglf/foo +++ /dev/null @@ -1,1 +0,0 @@ -7f7097b041ccf68cc5561e9600da4655d21c6d18 diff -r ff521236428a foo --- /dev/null +++ b/foo @@ -0,0 +1,1 @@ +normal $ cat foo normal Largefile in the working copy, keeping the largefile version: $ hg update -q -C -r 1 $ echo "l" | hg merge --config ui.interactive=Yes remote turned local largefile foo into a normal file keep (l)argefile or use (n)ormal file? l 0 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg status $ cat foo large Whatever ... commit something so we can invoke merge when updating $ hg commit -m '3: Merge' Updating from largefile to normal - no reason to prompt $ hg up -r 2 getting changed largefiles 0 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved $ cat foo normal (the update above used to leave the working dir in a very weird state - clean it $ hg up -qr null $ hg up -qr 2 ) Updating from normal to largefile - no reason to prompt $ hg up -r 3 getting changed largefiles 1 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved $ cat foo large $ cd .. Systematic testing of merges involving largefiles: Ancestor: normal Parent: normal-id Parent: large result: large Ancestor: normal Parent: normal2 Parent: large result: ? Ancestor: large Parent: large-id Parent: normal result: normal Ancestor: large Parent: large2 Parent: normal result: ? All cases should try merging both ways. Prepare test repo: $ hg init merges $ cd merges prepare cases with "normal" ancestor: $ hg up -qr null $ echo normal > f $ hg ci -Aqm "normal-ancestor" $ hg tag -l "normal-ancestor" $ touch f2 $ hg ci -Aqm "normal-id" $ hg tag -l "normal-id" $ echo normal2 > f $ hg ci -m "normal2" $ hg tag -l "normal2" $ echo normal > f $ hg ci -Aqm "normal-same" $ hg tag -l "normal-same" $ hg up -qr "normal-ancestor" $ hg rm f $ echo large > f $ hg add --large f $ hg ci -qm "large" $ hg tag -l "large" prepare cases with "large" ancestor: $ hg up -qr null $ echo large > f $ hg add --large f $ hg ci -qm "large-ancestor" $ hg tag -l "large-ancestor" $ touch f2 $ hg ci -Aqm "large-id" $ hg tag -l "large-id" $ echo large2 > f $ hg ci -m "large2" $ hg tag -l "large2" $ echo large > f $ hg ci -Aqm "large-same" $ hg tag -l "large-same" $ hg up -qr "large-ancestor" $ hg rm f $ echo normal > f $ hg ci -qAm "normal" $ hg tag -l "normal" $ hg log -GT '{tags}' @ normal tip | | o large-same | | | o large2 | | | o large-id |/ o large-ancestor o large | | o normal-same | | | o normal2 | | | o normal-id |/ o normal-ancestor Ancestor: normal Parent: normal-id Parent: large result: large $ hg up -Cqr normal-id $ hg merge -r large getting changed largefiles 1 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large swap $ hg up -Cqr large $ hg merge -r normal-id 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large Ancestor: normal Parent: normal-same Parent: large result: large $ hg up -Cqr normal-same $ hg merge -r large getting changed largefiles 1 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large swap $ hg up -Cqr large $ hg merge -r normal-same 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large Ancestor: normal Parent: normal2 Parent: large result: ? (annoying extra prompt ... but it do not do any serious harm) $ hg up -Cqr normal2 $ hg merge -r large remote turned local normal file f into a largefile use (l)argefile or keep (n)ormal file? l getting changed largefiles 1 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large $ hg up -Cqr normal2 $ echo n | hg merge -r large --config ui.interactive=Yes remote turned local normal file f into a largefile use (l)argefile or keep (n)ormal file? n 0 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal2 swap $ hg up -Cqr large $ hg merge -r normal2 remote turned local largefile f into a normal file keep (l)argefile or use (n)ormal file? l 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large $ hg up -Cqr large $ echo n | hg merge -r normal2 --config ui.interactive=Yes remote turned local largefile f into a normal file keep (l)argefile or use (n)ormal file? n getting changed largefiles 0 largefiles updated, 0 removed 2 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal2 Ancestor: large Parent: large-id Parent: normal result: normal $ hg up -Cqr large-id $ hg merge -r normal getting changed largefiles 0 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal swap $ hg up -Cqr normal $ hg merge -r large-id 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal Ancestor: large Parent: large-same Parent: normal result: normal $ hg up -Cqr large-same $ hg merge -r normal getting changed largefiles 0 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal swap $ hg up -Cqr normal $ hg merge -r large-same 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal Ancestor: large Parent: large2 Parent: normal result: ? (annoying extra prompt ... but it do not do any serious harm) $ hg up -Cqr large2 $ hg merge -r normal remote turned local largefile f into a normal file keep (l)argefile or use (n)ormal file? l 0 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large2 $ hg up -Cqr large2 $ echo n | hg merge -r normal --config ui.interactive=Yes remote turned local largefile f into a normal file keep (l)argefile or use (n)ormal file? n getting changed largefiles 0 largefiles updated, 0 removed 1 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal swap $ hg up -Cqr normal $ hg merge -r large2 remote turned local normal file f into a largefile use (l)argefile or keep (n)ormal file? l getting changed largefiles 1 largefiles updated, 0 removed 2 files updated, 0 files merged, 1 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f large2 $ hg up -Cqr normal $ echo n | hg merge -r large2 --config ui.interactive=Yes remote turned local normal file f into a largefile use (l)argefile or keep (n)ormal file? n 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat f normal $ cd ..