Implement asyncio support, plus session optimizations

[seandstewart]

This change adds support for asyncio. In order to do so, I made the following changes:

1. Isolated the use of the libraries behind a "Transport" abstraction.
2. Integrated errors and error handling within the "Transport" implementations.
3. Split the client implementation into BaseClient, Client, and AsyncClient.
4. Transports are designed to re-use a Session (connection pool), which each library provides. This is much more efficient than the top-level functions in requests or re-creating a session for every call.
5. Transports automatically handle deserialization from JSON and have default error handling for non-HTTP errors.
6. Adds tests for the new AsyncClient
7. Migrates the packaging to a modern toolchain for future-proofing (pyproject.toml, Poetry)

resolves #86

[seandstewart]

@rubydog I'd appreciate a review when you have time, this is a major blocker for my company's onboarding. Here is the test output below:

❯ make test-all
tox
.pkg: _optional_hooks> python /Users/seanstewart/PycharmProjects/contentful.py/venv/lib/python3.9/site-packages/pyproject_api/_backend.py True setuptools.build_meta __legacy__
.pkg: get_requires_for_build_sdist> python /Users/seanstewart/PycharmProjects/contentful.py/venv/lib/python3.9/site-packages/pyproject_api/_backend.py True setuptools.build_meta __legacy__
.pkg: get_requires_for_build_wheel> python /Users/seanstewart/PycharmProjects/contentful.py/venv/lib/python3.9/site-packages/pyproject_api/_backend.py True setuptools.build_meta __legacy__
.pkg: prepare_metadata_for_build_wheel> python /Users/seanstewart/PycharmProjects/contentful.py/venv/lib/python3.9/site-packages/pyproject_api/_backend.py True setuptools.build_meta __legacy__
.pkg: build_sdist> python /Users/seanstewart/PycharmProjects/contentful.py/venv/lib/python3.9/site-packages/pyproject_api/_backend.py True setuptools.build_meta __legacy__
py38-flakes: install_package> python -I -m pip install --force-reinstall --no-deps /Users/seanstewart/PycharmProjects/contentful.py/.tox/.tmp/package/33/contentful-2.1.1.tar.gz
py38-flakes: commands[0]> python -m unittest discover tests
.................................................................................................................................................................
----------------------------------------------------------------------
Ran 161 tests in 0.819s

OK
py38-flakes: OK ✔ in 2.25 seconds
py39-flakes: install_package> python -I -m pip install --force-reinstall --no-deps /Users/seanstewart/PycharmProjects/contentful.py/.tox/.tmp/package/34/contentful-2.1.1.tar.gz
py39-flakes: commands[0]> python -m unittest discover tests
.................................................................................................................................................................
----------------------------------------------------------------------
Ran 161 tests in 0.415s

OK
py39-flakes: OK ✔ in 1.98 seconds
py310-flakes: install_package> python -I -m pip install --force-reinstall --no-deps /Users/seanstewart/PycharmProjects/contentful.py/.tox/.tmp/package/35/contentful-2.1.1.tar.gz
py310-flakes: commands[0]> python -m unittest discover tests
.................................................................................................................................................................
----------------------------------------------------------------------
Ran 161 tests in 0.431s

OK
py310-flakes: OK ✔ in 1.5 seconds
py311-flakes: install_package> python -I -m pip install --force-reinstall --no-deps /Users/seanstewart/PycharmProjects/contentful.py/.tox/.tmp/package/36/contentful-2.1.1.tar.gz
py311-flakes: commands[0]> python -m unittest discover tests
.................................................................................................................................................................
----------------------------------------------------------------------
Ran 161 tests in 0.355s

OK
py311-flakes: OK ✔ in 1.46 seconds
py312-flakes: install_package> python -I -m pip install --force-reinstall --no-deps /Users/seanstewart/PycharmProjects/contentful.py/.tox/.tmp/package/37/contentful-2.1.1.tar.gz
py312-flakes: commands[0]> python -m unittest discover tests
.................................................................................................................................................................
----------------------------------------------------------------------
Ran 161 tests in 0.304s

OK
py312-flakes: OK ✔ in 2.54 seconds
pypy3-flakes: install_package> python -I -m pip install --force-reinstall --no-deps /Users/seanstewart/PycharmProjects/contentful.py/.tox/.tmp/package/38/contentful-2.1.1.tar.gz
pypy3-flakes: commands[0]> python -m unittest discover tests
.............Executing <Task pending name='Task-25' coro=<IsolatedAsyncioTestCase._asyncioLoopRunner() running at /Users/seanstewart/.pyenv/versions/pypy3.10-7.3.13/lib/pypy3.10/unittest/async_case.py:101> created at /Users/seanstewart/.pyenv/versions/pypy3.10-7.3.13/lib/pypy3.10/unittest/async_case.py:117> took 0.129 seconds
....................................................................................................................................................
----------------------------------------------------------------------
Ran 161 tests in 1.303s

OK
.pkg: _exit> python /Users/seanstewart/PycharmProjects/contentful.py/venv/lib/python3.9/site-packages/pyproject_api/_backend.py True setuptools.build_meta __legacy__
  py38-flakes: OK (2.25=setup[1.19]+cmd[1.05] seconds)
  py39-flakes: OK (1.98=setup[1.33]+cmd[0.65] seconds)
  py310-flakes: OK (1.50=setup[0.84]+cmd[0.67] seconds)
  py311-flakes: OK (1.46=setup[0.87]+cmd[0.59] seconds)
  py312-flakes: OK (2.54=setup[2.01]+cmd[0.53] seconds)
  pypy3-flakes: OK (3.26=setup[1.55]+cmd[1.71] seconds)
  congratulations :) (13.11 seconds)

[rubydog]

Hi @seandstewart, thanks for the PR.

I will take a look at it and try to get back to you by next week.

Cheers

[seandstewart]

Hi @seandstewart, thanks for the PR.

I will take a look at it and try to get back to you by next week.

Cheers

@rubydog Sounds good. I've gone through and added a self-review!

[pdelagrave]

Hello, any status update for this PR? We're eager to try it out :) Thanks

[rubydog]

Hi @pdelagrave,

We are currently discussing internally whether we want to support asyncio. Given the scope of this PR, it will take me some time to review it thoroughly. Apologies for the delay.