Files
7c1ca501eeeb6aa0067327b4f37d06244987e953
nova /HACKING.rst

168 lines
8.0 KiB
ReStructuredText
Raw Normal View History

2010年05月27日 23:05:26 -07:00
Nova Style Commandments
=======================
- Step 1: Read the OpenStack Style Commandments
https://docs.openstack.org/hacking/latest/
- Step 2: Read on
2010年05月27日 23:05:26 -07:00
Nova Specific Commandments
---------------------------
2011年07月29日 12:49:48 -04:00
- [N307] ``nova.db`` imports are not allowed in ``nova/virt/*``
- [N309] no db session in public API methods (disabled)
This enforces a guideline defined in ``oslo.db.sqlalchemy.session``
- [N310] timeutils.utcnow() wrapper must be used instead of direct calls to
datetime.datetime.utcnow() to make it easy to override its return value in tests
- [N311] importing code from other virt drivers forbidden
Code that needs to be shared between virt drivers should be moved
into a common module
- [N312] using config vars from other virt drivers forbidden
Config parameters that need to be shared between virt drivers
should be moved into a common module
- [N313] capitalize help string
Config parameter help strings should have a capitalized first letter
- [N316] Change assertTrue(isinstance(A, B)) by optimal assert like
assertIsInstance(A, B).
- [N317] Change assertEqual(type(A), B) by optimal assert like
assertIsInstance(A, B)
- [N319] Validate that logs are not translated.
- [N320] Setting CONF.* attributes directly in tests is forbidden. Use
self.flags(option=value) instead.
- [N322] Method's default argument shouldn't be mutable
- [N323] Ensure that the _() function is explicitly imported to ensure proper translations.
- [N324] Ensure that jsonutils.%(fun)s must be used instead of json.%(fun)s
- [N326] Translated messages cannot be concatenated. String should be included in translated message.
- [N332] Check that the api_version decorator is the first decorator on a method
- [N334] Change assertTrue/False(A in/not in B, message) to the more specific
assertIn/NotIn(A, B, message)
- [N335] Check for usage of deprecated assertRaisesRegexp
Performance: leverage dict comprehension in PEP-0274 PEP-0274 introduced dict comprehensions to replace dict constructor with a sequence of length-2 sequences, these are benefits copied from [1]: The dictionary constructor approach has two distinct disadvantages from the proposed syntax though. First, it isn't as legible as a dict comprehension. Second, it forces the programmer to create an in-core list object first, which could be expensive. Nova dropped python 2.6 support, we can leverage this now. There is deep dive about PEP-0274[2] and basic tests about performance[3]. Note: This commit doesn't handle dict constructor with kwagrs. This commit also adds a hacking rule. [1]http://legacy.python.org/dev/peps/pep-0274/ [2]http://doughellmann.com/2012/11/12/the-performance-impact-of-using-dict-instead-of-in-cpython-2-7-2.html [3]http://paste.openstack.org/show/154798/ Change-Id: Ifb5cb05b9cc2b8758d5a8e34f7792470a73d7c40
2014年12月24日 18:10:30 +08:00
- [N336] Must use a dict comprehension instead of a dict constructor with a sequence of key-value pairs.
- [N337] Don't import translation in tests
- [N338] Change assertEqual(A in B, True), assertEqual(True, A in B),
assertEqual(A in B, False) or assertEqual(False, A in B) to the more specific
assertIn/NotIn(A, B)
- [N339] Check common raise_feature_not_supported() is used for v2.1 HTTPNotImplemented response.
- [N340] Check nova.utils.spawn() is used instead of greenthread.spawn() and eventlet.spawn()
- [N341] contextlib.nested is deprecated
- [N342] Config options should be in the central location ``nova/conf/``
- [N343] Check for common double word typos
- [N348] Deprecated library function os.popen()
- [N349] Check for closures in tests which are not used
- [N350] Policy registration should be in the central location ``nova/policies/``
- [N351] Do not use the oslo_policy.policy.Enforcer.enforce() method.
- [N352] LOG.warn is deprecated. Enforce use of LOG.warning.
- [N353] Validate that context objects is not passed in logging calls.
- [N355] Enforce use of assertTrue/assertFalse
- [N356] Enforce use of assertIs/assertIsNot
- [N357] Use oslo_utils.uuidutils or uuidsentinel(in case of test cases) to
generate UUID instead of uuid4().
- [N358] Return must always be followed by a space when returning a value.
- [N359] Check for redundant import aliases.
- [N360] Yield must always be followed by a space when yielding a value.
- [N361] Check for usage of deprecated assertRegexpMatches and
assertNotRegexpMatches
- [N362] Imports for privsep modules should be specific. Use "import nova.privsep.path",
not "from nova.privsep import path". This ensures callers know that the method they're
calling is using priviledge escalation.
- [N363] Disallow ``(not_a_tuple)`` because you meant ``(a_tuple_of_one,)``.
- [N364] Check non-existent mock assertion methods and attributes.
- [N365] Check misuse of assertTrue/assertIsNone.
- [N366] The assert_has_calls is a method rather than a variable.
Creating Unit Tests
-------------------
For every new feature, unit tests should be created that both test and
(implicitly) document the usage of said feature. If submitting a patch for a
bug that had no unit test, a new passing unit test should be added. If a
submitted bug fix does have a unit test, be sure to add a new one that fails
without the patch and passes with the patch.
For more information on creating unit tests and utilizing the testing
infrastructure in OpenStack Nova, please read ``nova/tests/unit/README.rst``.
Running Tests
-------------
The testing system is based on a combination of tox and stestr. The canonical
approach to running tests is to simply run the command ``tox``. This will
create virtual environments, populate them with dependencies and run all of
the tests that OpenStack CI systems run. Behind the scenes, tox is running
``stestr run``, but is set up such that you can supply any additional
stestr arguments that are needed to tox. For example, you can run:
``tox -- --analyze-isolation`` to cause tox to tell stestr to add
--analyze-isolation to its argument list.
Python packages may also have dependencies that are outside of tox's ability
to install. Please refer to `Development Quickstart`_ for
a list of those packages on Ubuntu, Fedora and Mac OS X.
To run a single or restricted set of tests, pass a regex that matches
the class name containing the tests as an extra ``tox`` argument;
e.g. ``tox -- TestWSGIServer`` (note the double-hypen) will test all
WSGI server tests from ``nova/tests/unit/test_wsgi.py``; ``--
TestWSGIServer.test_uri_length_limit`` would run just that test, and
``-- TestWSGIServer|TestWSGIServerWithSSL`` would run tests from both
classes.
It is also possible to run the tests inside of a virtual environment
you have created, or it is possible that you have all of the dependencies
installed locally already. In this case, you can interact with the stestr
command directly. Running ``stestr run`` will run the entire test suite.
``stestr run --concurrency=1`` will run tests serially (by default, stestr runs
tests in parallel). More information about stestr can be found at:
http://stestr.readthedocs.io/
Make it easier to run a selection of tests relevant to ongoing work During development of a new git commit, locally running a whole unit or functional test suite to check every minor code change is prohibitively expensive. For maximum developer productivity and happiness, it's generally desirable to make the feedback loop of the traditional red/green cycle as quick as possible. So add run-tests-for-diff.sh and run-tests.py to the tools/ subdirectory, using a few tricks as explained below to help with this. run-tests.py takes a list of files on STDIN, filters the list for tests which can be run in the current tox virtualenv, and then runs them with the correct stestr options. run-tests-for-diff.sh is a simple wrapper around run-tests.py which determines which tests to run using output from "git diff". This allows running only the test files changed/added in the working tree: tools/run-tests-for-diff.sh or by a single commit: tools/run-tests-for-diff.sh mybranch^! or a range of commits, e.g. a branch containing a whole patch series for a blueprint: tools/run-tests-for-diff.sh gerrit/master..bp/my-blueprint It supports the same "-HEAD" invocation syntax as flake8wrap.sh (as used by the "fast8" tox environment): tools/run-tests-for-diff.sh -HEAD run-tests.py uses two tricks to make test runs as quick as possible: 1. It's (already) possible to speed up running of tests by source'ing the "activate" file for the desired tox virtualenv, e.g. source .tox/py36/bin/activate and then running stestr directly. This saves a few seconds by skipping the overhead introduced by running tox. 2. When only one test file needs to be run, specifying the -n option to stestr will skip the costly test discovery phase, saving several more valuable seconds. Future commits could build on top of this work, harnessing a framework such as watchdog / watchmedo[0] or Guard[1] in order to automatically run relevant tests every time your editor saves changes to a .py file. [0] https://github.com/gorakhargosh/watchdog - Python-based [1] https://guardgem.org - probably best in class, but Ruby-based so maybe unacceptable for use within Nova. Change-Id: I9a9bda5d29bbb8d8d77f769cd1abf7c42a18c36b
2019年08月19日 11:31:59 +01:00
Since when testing locally, running the entire test suite on a regular
basis is prohibitively expensive, the ``tools/run-tests-for-diff.sh``
script is provided as a convenient way to run selected tests using
output from ``git diff``. For example, this allows running only the
test files changed/added in the working tree::
tools/run-tests-for-diff.sh
However since it passes its arguments directly to ``git diff``, tests
can be selected in lots of other interesting ways, e.g. it can run all
tests affected by a single commit at the tip of a given branch::
tools/run-tests-for-diff.sh mybranch^!
or all those affected by a range of commits, e.g. a branch containing
a whole patch series for a blueprint::
tools/run-tests-for-diff.sh gerrit/master..bp/my-blueprint
It supports the same ``-HEAD`` invocation syntax as ``flake8wrap.sh``
(as used by the ``fast8`` tox environment)::
tools/run-tests-for-diff.sh -HEAD
By default tests log at ``INFO`` level. It is possible to make them
log at ``DEBUG`` level by exporting the ``OS_DEBUG`` environment
variable to ``True``.
.. _Development Quickstart: https://docs.openstack.org/nova/latest/contributor/development-environment.html
Building Docs
-------------
Normal Sphinx docs can be built via the setuptools ``build_sphinx`` command. To
do this via ``tox``, simply run ``tox -e docs``,
which will cause a virtualenv with all of the needed dependencies to be
created and then inside of the virtualenv, the docs will be created and
put into doc/build/html.
Building a PDF of the Documentation
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If you'd like a PDF of the documentation, you'll need LaTeX and ImageMagick
installed, and additionally some fonts. On Ubuntu systems, you can get what you
need with::
apt-get install texlive-full imagemagick
Then you can use the ``build_latex_pdf.sh`` script in tools/ to take care
of both the sphinx latex generation and the latex compilation. For example::
tools/build_latex_pdf.sh
The script must be run from the root of the Nova repository and it'll copy the
output pdf to Nova.pdf in that directory.