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
# If you want to change PREFIX, do not just edit it below. The changed
# value wont get passed on to recursive make calls. You should instead
# override the variable on the command like:
#
# % make PREFIX=/opt/ install
export PREFIX=/usr/local
PYTHON=python
$(eval HGROOT := $(shell pwd))
HGPYTHONS ?= $(HGROOT)/build/pythons
PURE=
PYFILES:=$(shell find mercurial hgext doc -name '*.py')
DOCFILES=mercurial/help/*.txt
export LANGUAGE=C
export LC_ALL=C
TESTFLAGS ?= $(shell echo $$HGTESTFLAGS)
OSXVERSIONFLAGS ?= $(shell echo $$OSXVERSIONFLAGS)
# Set this to e.g. "mingw32" to use a non-default compiler.
COMPILER=
COMPILERFLAG_tmp_ =
COMPILERFLAG_tmp_${COMPILER} ?= -c $(COMPILER)
COMPILERFLAG=${COMPILERFLAG_tmp_${COMPILER}}
help:
@echo 'Commonly used make targets:'
@echo ' all - build program and documentation'
@echo ' install - install program and man pages to $$PREFIX ($(PREFIX))'
@echo ' install-home - install with setup.py install --home=$$HOME ($(HOME))'
@echo ' local - build for inplace usage'
@echo ' tests - run all tests in the automatic test suite'
@echo ' test-foo - run only specified tests (e.g. test-merge1.t)'
@echo ' dist - run all tests and create a source tarball in dist/'
@echo ' clean - remove files created by other targets'
@echo ' (except installed files or dist source tarball)'
@echo ' update-pot - update i18n/hg.pot'
@echo
@echo 'Example for a system-wide installation under /usr/local:'
@echo ' make all && su -c "make install" && hg version'
@echo
@echo 'Example for a local installation (usable in this directory):'
@echo ' make local && ./hg version'
all: build doc
local:
$(PYTHON) setup.py $(PURE) \
build_py -c -d . \
build_ext $(COMPILERFLAG) -i \
build_hgexe $(COMPILERFLAG) -i \
build_mo
env HGRCPATH= $(PYTHON) hg version
build:
$(PYTHON) setup.py $(PURE) build $(COMPILERFLAG)
wheel:
FORCE_SETUPTOOLS=1 $(PYTHON) setup.py $(PURE) bdist_wheel $(COMPILERFLAG)
doc:
$(MAKE) -C doc
cleanbutpackages:
-$(PYTHON) setup.py clean --all # ignore errors from this command
find contrib doc hgext hgext3rd i18n mercurial tests hgdemandimport \
\( -name '*.py[cdo]' -o -name '*.so' \) -exec rm -f '{}' ';'
rm -f MANIFEST MANIFEST.in hgext/__index__.py tests/*.err
rm -f mercurial/__modulepolicy__.py
if test -d .hg; then rm -f mercurial/__version__.py; fi
rm -rf build mercurial/locale
$(MAKE) -C doc clean
$(MAKE) -C contrib/chg distclean
clean: cleanbutpackages
rm -rf packages
install: install-bin install-doc
install-bin: build
$(PYTHON) setup.py $(PURE) install --root="$(DESTDIR)/" --prefix="$(PREFIX)" --force
install-doc: doc
cd doc && $(MAKE) $(MFLAGS) install
install-home: install-home-bin install-home-doc
install-home-bin: build
$(PYTHON) setup.py $(PURE) install --home="$(HOME)" --prefix="" --force
install-home-doc: doc
cd doc && $(MAKE) $(MFLAGS) PREFIX="$(HOME)" install
MANIFEST-doc:
$(MAKE) -C doc MANIFEST
MANIFEST.in: MANIFEST-doc
hg manifest | sed -e 's/^/include /' > MANIFEST.in
echo include mercurial/__version__.py >> MANIFEST.in
sed -e 's/^/include /' < doc/MANIFEST >> MANIFEST.in
dist: tests dist-notests
dist-notests: doc MANIFEST.in
TAR_OPTIONS="--owner=root --group=root --mode=u+w,go-w,a+rX-s" $(PYTHON) setup.py -q sdist
check: tests
tests:
cd tests && $(PYTHON) run-tests.py $(TESTFLAGS)
test-%:
cd tests && $(PYTHON) run-tests.py $(TESTFLAGS) $@
testpy-%:
@echo Looking for Python $* in $(HGPYTHONS)
[ -e $(HGPYTHONS)/$*/bin/python ] || ( \
cd $$(mktemp --directory --tmpdir) && \
$(MAKE) -f $(HGROOT)/contrib/Makefile.python PYTHONVER=$* PREFIX=$(HGPYTHONS)/$* python )
cd tests && $(HGPYTHONS)/$*/bin/python run-tests.py $(TESTFLAGS)
check-code:
hg manifest | xargs python contrib/check-code.py
format-c:
clang-format --style file -i \
`hg files 'set:(**.c or **.cc or **.h) and not "listfile:contrib/clang-format-ignorelist"'`
update-pot: i18n/hg.pot
i18n/hg.pot: $(PYFILES) $(DOCFILES) i18n/posplit i18n/hggettext
$(PYTHON) i18n/hggettext mercurial/commands.py \
hgext/*.py hgext/*/__init__.py \
mercurial/fileset.py mercurial/revset.py \
mercurial/templatefilters.py \
mercurial/templatefuncs.py \
mercurial/templatekw.py \
mercurial/filemerge.py \
mercurial/hgweb/webcommands.py \
mercurial/util.py \
$(DOCFILES) > i18n/hg.pot.tmp
# All strings marked for translation in Mercurial contain
# ASCII characters only. But some files contain string
# literals like this '\037\213'. xgettext thinks it has to
# parse them even though they are not marked for translation.
# Extracting with an explicit encoding of ISO-8859-1 will make
# xgettext "parse" and ignore them.
echo $(PYFILES) | xargs \
xgettext --package-name "Mercurial" \
--msgid-bugs-address "<mercurial-devel@mercurial-scm.org>" \
--copyright-holder "Matt Mackall <mpm@selenic.com> and others" \
--from-code ISO-8859-1 --join --sort-by-file --add-comments=i18n: \
-d hg -p i18n -o hg.pot.tmp
$(PYTHON) i18n/posplit i18n/hg.pot.tmp
# The target file is not created before the last step. So it never is in
# an intermediate state.
mv -f i18n/hg.pot.tmp i18n/hg.pot
%.po: i18n/hg.pot
# work on a temporary copy for never having a half completed target
cp $@ $@.tmp
msgmerge --no-location --update $@.tmp $^
mv -f $@.tmp $@
# Packaging targets
osx:
rm -rf build/mercurial
/usr/bin/python2.7 setup.py install --optimize=1 \
--root=build/mercurial/ --prefix=/usr/local/ \
--install-lib=/Library/Python/2.7/site-packages/
make -C doc all install DESTDIR="$(PWD)/build/mercurial/"
# Place a bogon .DS_Store file in the target dir so we can be
# sure it doesn't get included in the final package.
touch build/mercurial/.DS_Store
# install zsh completions - this location appears to be
# searched by default as of macOS Sierra.
install -d build/mercurial/usr/local/share/zsh/site-functions/
install -m 0644 contrib/zsh_completion build/mercurial/usr/local/share/zsh/site-functions/_hg
# install bash completions - there doesn't appear to be a
# place that's searched by default for bash, so we'll follow
# the lead of Apple's git install and just put it in a
# location of our own.
install -d build/mercurial/usr/local/hg/contrib/
install -m 0644 contrib/bash_completion build/mercurial/usr/local/hg/contrib/hg-completion.bash
make -C contrib/chg \
HGPATH=/usr/local/bin/hg \
PYTHON=/usr/bin/python2.7 \
HGEXTDIR=/Library/Python/2.7/site-packages/hgext \
DESTDIR=../../build/mercurial \
PREFIX=/usr/local \
clean install
mkdir -p $${OUTPUTDIR:-dist}
HGVER=$$(python contrib/genosxversion.py $(OSXVERSIONFLAGS) build/mercurial/Library/Python/2.7/site-packages/mercurial/__version__.py) && \
OSXVER=$$(sw_vers -productVersion | cut -d. -f1,2) && \
pkgbuild --filter \\.DS_Store --root build/mercurial/ \
--identifier org.mercurial-scm.mercurial \
--version "$${HGVER}" \
build/mercurial.pkg && \
productbuild --distribution contrib/macosx/distribution.xml \
--package-path build/ \
--version "$${HGVER}" \
--resources contrib/macosx/ \
"$${OUTPUTDIR:-dist/}"/Mercurial-"$${HGVER}"-macosx"$${OSXVER}".pkg
deb:
contrib/builddeb
ppa:
contrib/builddeb --source-only
contrib/docker/debian-%: contrib/docker/debian.template
sed "s/__CODENAME__/$*/" $< > $@
docker-debian-jessie: contrib/docker/debian-jessie
mkdir -p packages/debian-jessie
contrib/dockerdeb debian jessie
docker-debian-stretch: contrib/docker/debian-stretch
mkdir -p packages/debian-stretch
contrib/dockerdeb debian stretch
contrib/docker/ubuntu-%: contrib/docker/ubuntu.template
sed "s/__CODENAME__/$*/" $< > $@
docker-ubuntu-trusty: contrib/docker/ubuntu-trusty
contrib/dockerdeb ubuntu trusty
docker-ubuntu-trusty-ppa: contrib/docker/ubuntu-trusty
contrib/dockerdeb ubuntu trusty --source-only
docker-ubuntu-xenial: contrib/docker/ubuntu-xenial
contrib/dockerdeb ubuntu xenial
docker-ubuntu-xenial-ppa: contrib/docker/ubuntu-xenial
contrib/dockerdeb ubuntu xenial --source-only
docker-ubuntu-artful: contrib/docker/ubuntu-artful
contrib/dockerdeb ubuntu artful
docker-ubuntu-artful-ppa: contrib/docker/ubuntu-artful
contrib/dockerdeb ubuntu artful --source-only
fedora20:
mkdir -p packages/fedora20
contrib/buildrpm
cp rpmbuild/RPMS/*/* packages/fedora20
cp rpmbuild/SRPMS/* packages/fedora20
rm -rf rpmbuild
docker-fedora20:
mkdir -p packages/fedora20
contrib/dockerrpm fedora20
fedora21:
mkdir -p packages/fedora21
contrib/buildrpm
cp rpmbuild/RPMS/*/* packages/fedora21
cp rpmbuild/SRPMS/* packages/fedora21
rm -rf rpmbuild
docker-fedora21:
mkdir -p packages/fedora21
contrib/dockerrpm fedora21
centos5:
mkdir -p packages/centos5
contrib/buildrpm --withpython
cp rpmbuild/RPMS/*/* packages/centos5
cp rpmbuild/SRPMS/* packages/centos5
docker-centos5:
mkdir -p packages/centos5
contrib/dockerrpm centos5 --withpython
centos6:
mkdir -p packages/centos6
contrib/buildrpm --withpython
cp rpmbuild/RPMS/*/* packages/centos6
cp rpmbuild/SRPMS/* packages/centos6
docker-centos6:
mkdir -p packages/centos6
contrib/dockerrpm centos6 --withpython
centos7:
mkdir -p packages/centos7
contrib/buildrpm
cp rpmbuild/RPMS/*/* packages/centos7
cp rpmbuild/SRPMS/* packages/centos7
docker-centos7:
mkdir -p packages/centos7
contrib/dockerrpm centos7
linux-wheels: linux-wheels-x86_64 linux-wheels-i686
linux-wheels-x86_64:
docker run -e "HGTEST_JOBS=$(shell nproc)" --rm -ti -v `pwd`:/src quay.io/pypa/manylinux1_x86_64 /src/contrib/build-linux-wheels.sh
linux-wheels-i686:
docker run -e "HGTEST_JOBS=$(shell nproc)" --rm -ti -v `pwd`:/src quay.io/pypa/manylinux1_i686 linux32 /src/contrib/build-linux-wheels.sh
.PHONY: help all local build doc cleanbutpackages clean install install-bin \
install-doc install-home install-home-bin install-home-doc \
dist dist-notests check tests check-code format-c update-pot \
osx deb ppa docker-debian-jessie docker-debian-stretch \
docker-ubuntu-trusty docker-ubuntu-trusty-ppa \
docker-ubuntu-xenial docker-ubuntu-xenial-ppa \
docker-ubuntu-artful docker-ubuntu-artful-ppa \
fedora20 docker-fedora20 fedora21 docker-fedora21 \
centos5 docker-centos5 centos6 docker-centos6 centos7 docker-centos7 \
linux-wheels