2022-07-12 04:27:04 -06:00
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2022-07-19 06:39:06 -06:00
< ol class = "chapter" > < li class = "chapter-item expanded affix " > < li class = "part-title" > Introduction< / li > < li class = "chapter-item expanded " > < a href = "../welcome_and_overview.html" > Welcome and Overview< / a > < / li > < li class = "chapter-item expanded affix " > < li class = "part-title" > Setup< / li > < li class = "chapter-item expanded " > < a href = "../setup/installation.html" > Installation< / a > < / li > < li class = "chapter-item expanded " > < a href = "../postgres.html" > Using Postgres< / a > < / li > < li class = "chapter-item expanded " > < a href = "../reverse_proxy.html" > Configuring a Reverse Proxy< / a > < / li > < li class = "chapter-item expanded " > < a href = "../setup/forward_proxy.html" > Configuring a Forward/Outbound Proxy< / a > < / li > < li class = "chapter-item expanded " > < a href = "../turn-howto.html" > Configuring a Turn Server< / a > < / li > < li class = "chapter-item expanded " > < a href = "../delegate.html" > Delegation< / a > < / li > < li class = "chapter-item expanded affix " > < li class = "part-title" > Upgrading< / li > < li class = "chapter-item expanded " > < a href = "../upgrade.html" > Upgrading between Synapse Versions< / a > < / li > < li class = "chapter-item expanded affix " > < li class = "part-title" > Usage< / li > < li class = "chapter-item expanded " > < a href = "../federate.html" > Federation< / a > < / li > < li class = "chapter-item expanded " > < a href = "../usage/configuration/index.html" > Configuration< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../usage/configuration/config_documentation.html" > Configuration Manual< / a > < / li > < li class = "chapter-item expanded " > < a href = "../usage/configuration/homeserver_sample_config.html" > Homeserver Sample Config File< / a > < / li > < li class = "chapter-item expanded " > < a href = "../usage/configuration/logging_sample_config.html" > Logging Sample Config File< / a > < / li > < li class = "chapter-item expanded " > < a href = "../structured_logging.html" > Structured Logging< / a > < / li > < li class = "chapter-item expanded " > < a href = "../templates.html" > Templates< / a > < / li > < li class = "chapter-item expanded " > < a href = "../usage/configuration/user_authentication/index.html" > User Authentication< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../usage/configuration/user_authentication/single_sign_on/index.html" > Single-Sign On< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../openid.html" > OpenID Connect< / a > < / li > < li class = "chapter-item expanded " > < a href = "../usage/configuration/user_authentication/single_sign_on/saml.html" > SAML< / a > < / li > < li class = "chapter-item expanded " > < a href = "../usage/configuration/user_authentication/single_sign_on/cas.html" > CAS< / a > < / li > < li class = "chapter-item expanded " > < a href = "../sso_mapping_providers.html" > SSO Mapping Providers< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../password_auth_providers.html" > Password Auth Providers< / a > < / li > < li class = "chapter-item expanded " > < a href = "../jwt.html" > JSON Web Tokens< / a > < / li > < li class = "chapter-item expanded " > < a href = "../usage/configuration/user_authentication/refresh_tokens.html" > Refresh Tokens< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../CAPTCHA_SETUP.html" > Registration Captcha< / a > < / li > < li class = "chapter-item expanded " > < a href = "../application_services.html" > Application Services< / a > < / li > < li class = "chapter-item expanded " > < a href = "../server_notices.html" > Server Notices< / a > < / li > < li class = "chapter-item expanded " > < a href = "../consent_tracking.html" > Consent Tracking< / a > < / li > < li class = "chapter-item expanded " > < a href = "../development/url_previews.html" > URL Previews< / a > < / li > < li class = "chapter-item expanded " > < a href = "../user_directory.html" > User Directory< / a > < / li > < li class = "chapter-item expanded " > < a href = "../message_retention_policies.html" > Message Retention Policies< / a > < / li > < li class = "chapter-item expanded " > < a href = "../modules/index.html" > Pluggable Modules< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../modules/writing_a_module.html" > Writing a module< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../modules/spam_checker_callbacks.html" > Spam checker callbacks< / a > < / li > < li class = "chapter-item expanded " > < a href = "../modul
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< h1 id = "managing-dependencies-with-poetry" > < a class = "header" href = "#managing-dependencies-with-poetry" > Managing dependencies with Poetry< / a > < / h1 >
< p > This is a quick cheat sheet for developers on how to use < a href = "https://python-poetry.org/" > < code > poetry< / code > < / a > .< / p >
< h1 id = "background" > < a class = "header" href = "#background" > Background< / a > < / h1 >
< p > Synapse uses a variety of third-party Python packages to function as a homeserver.
Some of these are direct dependencies, listed in < code > pyproject.toml< / code > under the
< code > [tool.poetry.dependencies]< / code > section. The rest are transitive dependencies (the
things that our direct dependencies themselves depend on, and so on recursively.)< / p >
< p > We maintain a locked list of all our dependencies (transitive included) so that
we can track exactly which version of each dependency appears in a given release.
See < a href = "https://github.com/matrix-org/synapse/issues/11537#issue-1074469665" > here< / a >
for discussion of why we wanted this for Synapse. We chose to use
< a href = "https://python-poetry.org/" > < code > poetry< / code > < / a > to manage this locked list; see
< a href = "https://github.com/matrix-org/synapse/issues/11537#issuecomment-1015975819" > this comment< / a >
for the reasoning.< / p >
< p > The locked dependencies get included in our " self-contained" releases: namely,
our docker images and our debian packages. We also use the locked dependencies
in development and our continuous integration.< / p >
< p > Separately, our " broad" dependencies—the version ranges specified in
< code > pyproject.toml< / code > —are included as metadata in our " sdists" and " wheels" < a href = "https://pypi.org/project/matrix-synapse" > uploaded
to PyPI< / a > . Installing from PyPI or from
the Synapse source tree directly will < em > not< / em > use the locked dependencies; instead,
they'll pull in the latest version of each package available at install time.< / p >
< h2 id = "example-dependency" > < a class = "header" href = "#example-dependency" > Example dependency< / a > < / h2 >
< p > An example may help. We have a broad dependency on
< a href = "https://pypi.org/project/phonenumbers/" > < code > phonenumbers< / code > < / a > , as declared in
this snippet from pyproject.toml < a href = "https://github.com/matrix-org/synapse/blob/release-v1.57/pyproject.toml#L133" > as of Synapse 1.57< / a > :< / p >
< pre > < code class = "language-toml" > [tool.poetry.dependencies]
# ...
phonenumbers = " > =8.2.0"
< / code > < / pre >
< p > In our lockfile this is
< a href = "https://github.com/matrix-org/synapse/blob/dfc7646504cef3e4ff396c36089e1c6f1b1634de/poetry.lock#L679-L685" > pinned< / a >
to version 8.12.44, even though
< a href = "https://pypi.org/project/phonenumbers/#history" > newer versions are available< / a > .< / p >
< pre > < code class = "language-toml" > [[package]]
name = " phonenumbers"
version = " 8.12.44"
description = " Python version of Google's common library for parsing, formatting, storing and validating international phone numbers."
category = " main"
optional = false
python-versions = " *"
< / code > < / pre >
< p > The lockfile also includes a
< a href = "https://github.com/matrix-org/synapse/blob/release-v1.57/poetry.lock#L2178-L2181" > cryptographic checksum< / a >
of the sdists and wheels provided for this version of < code > phonenumbers< / code > .< / p >
< pre > < code class = "language-toml" > [metadata.files]
# ...
phonenumbers = [
{file = " phonenumbers-8.12.44-py2.py3-none-any.whl" , hash = " sha256:cc1299cf37b309ecab6214297663ab86cb3d64ae37fd5b88e904fe7983a874a6" },
{file = " phonenumbers-8.12.44.tar.gz" , hash = " sha256:26cfd0257d1704fe2f88caff2caabb70d16a877b1e65b6aae51f9fbbe10aa8ce" },
]
< / code > < / pre >
< p > We can see this pinned version inside the docker image for that release:< / p >
< pre > < code > $ docker pull matrixdotorg/synapse:v1.57.0
...
$ docker run --entrypoint pip matrixdotorg/synapse:v1.57.0 show phonenumbers
Name: phonenumbers
Version: 8.12.44
Summary: Python version of Google's common library for parsing, formatting, storing and validating international phone numbers.
Home-page: https://github.com/daviddrysdale/python-phonenumbers
Author: David Drysdale
Author-email: dmd@lurklurk.org
License: Apache License 2.0
Location: /usr/local/lib/python3.9/site-packages
Requires:
Required-by: matrix-synapse
< / code > < / pre >
< p > Whereas the wheel metadata just contains the broad dependencies:< / p >
< pre > < code > $ cd /tmp
$ wget https://files.pythonhosted.org/packages/ca/5e/d722d572cc5b3092402b783d6b7185901b444427633bd8a6b00ea0dd41b7/matrix_synapse-1.57.0rc1-py3-none-any.whl
...
$ unzip -c matrix_synapse-1.57.0rc1-py3-none-any.whl matrix_synapse-1.57.0rc1.dist-info/METADATA | grep phonenumbers
Requires-Dist: phonenumbers (> =8.2.0)
< / code > < / pre >
< h1 id = "tooling-recommendation-direnv" > < a class = "header" href = "#tooling-recommendation-direnv" > Tooling recommendation: direnv< / a > < / h1 >
< p > < a href = "https://direnv.net/" > < code > direnv< / code > < / a > is a tool for activating environments in your
shell inside a given directory. Its support for poetry is unofficial (a
community wiki recipe only), but works solidly in our experience. We thoroughly
recommend it for daily use. To use it:< / p >
< ol >
< li > < a href = "https://direnv.net/docs/installation.html" > Install < code > direnv< / code > < / a > - it's likely
packaged for your system already.< / li >
< li > Teach direnv about poetry. The < a href = "https://github.com/direnv/direnv/wiki/Python#poetry" > shell config here< / a >
needs to be added to < code > ~/.config/direnv/direnvrc< / code > (or more generally < code > $XDG_CONFIG_HOME/direnv/direnvrc< / code > ).< / li >
< li > Mark the synapse checkout as a poetry project: < code > echo layout poetry > .envrc< / code > .< / li >
< li > Convince yourself that you trust this < code > .envrc< / code > configuration and project.
Then formally confirm this to < code > direnv< / code > by running < code > direnv allow< / code > .< / li >
< / ol >
< p > Then whenever you navigate to the synapse checkout, you should be able to run
e.g. < code > mypy< / code > instead of < code > poetry run mypy< / code > ; < code > python< / code > instead of
< code > poetry run python< / code > ; and your shell commands will automatically run in the
context of poetry's venv, without having to run < code > poetry shell< / code > beforehand.< / p >
< h1 id = "how-do-i" > < a class = "header" href = "#how-do-i" > How do I...< / a > < / h1 >
< h2 id = "reset-my-venv-to-the-locked-environment" > < a class = "header" href = "#reset-my-venv-to-the-locked-environment" > ...reset my venv to the locked environment?< / a > < / h2 >
< pre > < code class = "language-shell" > poetry install --extras all --remove-untracked
< / code > < / pre >
< h2 id = "run-a-command-in-the-poetry-virtualenv" > < a class = "header" href = "#run-a-command-in-the-poetry-virtualenv" > ...run a command in the < code > poetry< / code > virtualenv?< / a > < / h2 >
< p > Use < code > poetry run cmd args< / code > when you need the python virtualenv context.
To avoid typing < code > poetry run< / code > all the time, you can run < code > poetry shell< / code >
to start a new shell in the poetry virtualenv context. Within < code > poetry shell< / code > ,
< code > python< / code > , < code > pip< / code > , < code > mypy< / code > , < code > trial< / code > , etc. are all run inside the project virtualenv
and isolated from the rest o the system.< / p >
< p > Roughly speaking, the translation from a traditional virtualenv is:< / p >
< ul >
< li > < code > env/bin/activate< / code > -> < code > poetry shell< / code > , and< / li >
< li > < code > deactivate< / code > -> close the terminal (Ctrl-D, < code > exit< / code > , etc.)< / li >
< / ul >
< p > See also the direnv recommendation above, which makes < code > poetry run< / code > and
< code > poetry shell< / code > unnecessary.< / p >
< h2 id = "inspect-the-poetry-virtualenv" > < a class = "header" href = "#inspect-the-poetry-virtualenv" > ...inspect the < code > poetry< / code > virtualenv?< / a > < / h2 >
< p > Some suggestions:< / p >
< pre > < code class = "language-shell" > # Current env only
poetry env info
# All envs: this allows you to have e.g. a poetry managed venv for Python 3.7,
# and another for Python 3.10.
poetry env list --full-path
poetry run pip list
< / code > < / pre >
< p > Note that < code > poetry show< / code > describes the abstract < em > lock file< / em > rather than your
on-disk environment. With that said, < code > poetry show --tree< / code > can sometimes be
useful.< / p >
< h2 id = "add-a-new-dependency" > < a class = "header" href = "#add-a-new-dependency" > ...add a new dependency?< / a > < / h2 >
< p > Either:< / p >
< ul >
< li > manually update < code > pyproject.toml< / code > ; then < code > poetry lock --no-update< / code > ; or else< / li >
< li > < code > poetry add packagename< / code > . See < code > poetry add --help< / code > ; note the < code > --dev< / code > ,
< code > --extras< / code > and < code > --optional< / code > flags in particular.
< ul >
< li > < strong > NB< / strong > : this specifies the new package with a version given by a " caret bound" . This won't get forced to its lowest version in the old deps CI job: see < a href = "https://github.com/matrix-org/synapse/blob/4e1374373857f2f7a911a31c50476342d9070681/.ci/scripts/test_old_deps.sh#L35-L39" > this TODO< / a > .< / li >
< / ul >
< / li >
< / ul >
< p > Include the updated < code > pyproject.toml< / code > and < code > poetry.lock< / code > files in your commit.< / p >
< h2 id = "remove-a-dependency" > < a class = "header" href = "#remove-a-dependency" > ...remove a dependency?< / a > < / h2 >
< p > This is not done often and is untested, but< / p >
< pre > < code class = "language-shell" > poetry remove packagename
< / code > < / pre >
< p > ought to do the trick. Alternatively, manually update < code > pyproject.toml< / code > and
< code > poetry lock --no-update< / code > . Include the updated < code > pyproject.toml< / code > and poetry.lock`
files in your commit.< / p >
< h2 id = "update-the-version-range-for-an-existing-dependency" > < a class = "header" href = "#update-the-version-range-for-an-existing-dependency" > ...update the version range for an existing dependency?< / a > < / h2 >
< p > Best done by manually editing < code > pyproject.toml< / code > , then < code > poetry lock --no-update< / code > .
Include the updated < code > pyproject.toml< / code > and < code > poetry.lock< / code > in your commit.< / p >
< h2 id = "update-a-dependency-in-the-locked-environment" > < a class = "header" href = "#update-a-dependency-in-the-locked-environment" > ...update a dependency in the locked environment?< / a > < / h2 >
< p > Use< / p >
< pre > < code class = "language-shell" > poetry update packagename
< / code > < / pre >
< p > to use the latest version of < code > packagename< / code > in the locked environment, without
affecting the broad dependencies listed in the wheel.< / p >
< p > There doesn't seem to be a way to do this whilst locking a < em > specific< / em > version of
< code > packagename< / code > . We can workaround this (crudely) as follows:< / p >
< pre > < code class = "language-shell" > poetry add packagename==1.2.3
# This should update pyproject.lock.
# Now undo the changes to pyproject.toml. For example
# git restore pyproject.toml
# Get poetry to recompute the content-hash of pyproject.toml without changing
# the locked package versions.
poetry lock --no-update
< / code > < / pre >
< p > Either way, include the updated < code > poetry.lock< / code > file in your commit.< / p >
< h2 id = "export-a-requirementstxt-file" > < a class = "header" href = "#export-a-requirementstxt-file" > ...export a < code > requirements.txt< / code > file?< / a > < / h2 >
< pre > < code class = "language-shell" > poetry export --extras all
< / code > < / pre >
< p > Be wary of bugs in < code > poetry export< / code > and < code > pip install -r requirements.txt< / code > .< / p >
< p > Note: < code > poetry export< / code > will be made a plugin in Poetry 1.2. Additional config may
be required.< / p >
< h2 id = "build-a-test-wheel" > < a class = "header" href = "#build-a-test-wheel" > ...build a test wheel?< / a > < / h2 >
< p > I usually use< / p >
< pre > < code class = "language-shell" > poetry run pip install build & & poetry run python -m build
< / code > < / pre >
< p > because < a href = "https://github.com/pypa/build" > < code > build< / code > < / a > is a standardish tool which
doesn't require poetry. (It's what we use in CI too). However, you could try
< code > poetry build< / code > too.< / p >
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