GENERAL DEVELOPMENT NOTES ================================================= Project's sources are accessible from a `Mercurial version control repository `_ hosted at BitBucket. Project development should be tracked in the ``TODO.txt`` file. * Exact formatting is not important as long as its content is kept formatted consistently. * Done tasks should be marked as such and not deleted. Separate sections below: * `TOP-LEVEL PROJECT FILES & FOLDERS`_ * `PYTHON COMPATIBILITY`_ * `RELEASE PROCEDURE`_ * `DEVELOPMENT & TESTING ENVIRONMENT`_ * `PYTHON 2/3 SOURCE CODE COMPATIBILITY`_ * `EXTERNAL DOCUMENTATION`_ * `STANDARDS CONFORMANCE`_ * `PROJECT IMPLEMENTATION NOTES`_ * `REPRODUCING PROBLEMATIC USE CASES`_ For additional design, research & development project notes see the project's ``notes/`` folder. TOP-LEVEL PROJECT FILES & FOLDERS ================================================= | .hg/ | .hgignore | .hgtags * Mercurial version control related data. | build/ | dist/ | suds_jurko.egg-info/ * Folders created during project setup procedure (build/install). | notes/ * Internal project design, research & development notes. | suds/ * Basic project source code. | tests/ * Project test code. | tools/ * Project development & setup utility scripts. Related internal Python modules are located under its ``suds_devel/`` package folder. | MANIFEST.in * Build system configuration file listing the files to be included in the project's source distribution packages in addition to those automatically added to those packages by the used package preparation system. | HACKING.rst | LICENSE.txt | README.txt | TODO.txt * Internal project documentation. | setup.cfg * Basic project Python configuration. | setup.py * Standard Python project setup script. * Usage examples: ``setup.py --help`` show detailed usage information ``setup.py --help-commands`` show detailed ``setup.py`` command list ``setup.py build`` build the project ``setup.py install`` build & install the project ``setup.py register`` register a project release at PyPI ``setup.py sdist`` prepare a source distribution ``setup.py upload`` upload prepared packages to PyPI * Usage examples requiring ``setuptools``: ``setup.py develop`` prepare the development environment (add the project folder to the Python module search path) the same as if installed using ``easy_install -e`` or ``pip install -e`` ``setup.py test`` run the project test suite (requires ``pytest``) PYTHON COMPATIBILITY ================================================= Base sources should remain Python 2.x compatible. Since the original project states aiming for Python 2.4 compatibility we do so as well. The Python 3.0 minor release is not supported. See `Python 3.0 support`_ subsection below for more detailed information. Test & setup code needs to be implemented using Python 2 & 3 compatible source code. Setup & setup related scripts need to be implemented so they do not rely on other pre-installed libraries. These backward compatibility requirements do not affect internal development operations such as ``setup.py`` support for uploading a new project distribution package to PyPI. Such operations need to be supported on the latest Python 2 & 3 releases only and no additional backward compatibility is either tested or guaranteed for them. The following is a list of backward incompatible Python features not used in this project to maintain backward compatibility: Features missing prior to Python 2.5 ------------------------------------ * ``any`` & ``all`` functions. * ``with`` statement. * BaseException class introduced and KeyboardInterrupt & SystemExit exception classes stopped being Exception subclasses. * This means that code wanting to support Python versions prior to this release needs to re-raise KeyboardInterrupt & SystemExit exceptions before handling the generic 'Exception' case, unless it really wants to gobble up those special infrastructural exceptions as well. * ``try``/``except``/``finally`` blocks. * Prior to this Python release, code like the following:: try: A except XXX: B finally: C was considered illegal and needed to be written using nested ``try`` blocks as in:: try: try: A except XXX: B finally: C * ``yield`` expression inside a ``try`` block with a ``finally`` clause. * Prior to this Python release, code like the following:: try: yield x finally: do_something() is considered illegal, but can be replaced with legal code similar to the following:: try: yield x except: do_something() raise do_something() Features missing prior to Python 2.6 ------------------------------------ * ``bytes`` type. * Byte literals, e.g. ``b"quack"``. * Class decorators. * ``fractions`` module. * ``numbers`` module. * String ``format()`` method. * Using the ``with`` statement from Python 2.5.x requires the ``from __future__ import with_statement``. Features missing prior to Python 2.7 ------------------------------------ * Dictionary & set comprehensions. * Set literals. Features missing in Python 3.0 & 3.1 ------------------------------------ * py2to3 conversion for source files with an explicitly specified UTF-8 BOM. Python 3.0 support ------------------ Python 3.0 release has been marked as deprecated almost immediately after the release 3.1. It is not expected that this Python release is actively used anywhere in the wild. That said, if anyone really wants this version supported - patches are welcome. At least the following problems have been found with Python 3.0: * None of the tools required to properly test our project (setuptools, pip, virtualenv, tox, etc.) will work on it. * When you attempt to setuptools project with Python 3.0, it attempts to use the ``sys.stdout.detach()`` method introduced only in Python 3.1. This specific issue could be worked around by using ``sys.stdout.buffer`` directly but the actual fix has not been attempted. If anyone wants to take this route though and work on supporting setuptools on Python 3.0 - be warned that it will most likely have other issues after this one as well. * When applying py2to3 to the project sources, Python will use the current user's locale encoding instead of the one specified in the project sources, thus causing the operation to fail on some source files containing different unicode characters unless the user's environement uses some sort of unicode encoding by default, e.g. will fail on some test scripts when run on Windows with eastern European regional settings (uses the CP1250 encoding). RELEASE PROCEDURE ================================================= 1. Document the release correctly in ``README.rst``. 2. Test the project build with the latest available ``setuptools`` project and update the ``ez_setup.py`` ``setuptools`` installation script as needed. * Use the latest available & tested ``setuptools`` release. * If a new ``setuptools`` release drops support for an older Python release, update our ``setup.py`` script to use an older ``setuptools`` installation script when run using the no longer supported Python release. * For example, ``setuptools`` version 2.0 dropped support for Python 2.4 & 2.5 and so ``setup.py`` uses a separate ``ez_setup_1_4_2.py`` ``setuptools`` installation script with Python versions older than 2.6. 3. Version identification. * Official releases marked with no extra suffix after the basic version number. * Alfa releases marked with the suffix ``.a#``. * Beta releases marked with the suffix ``.b#``. * Release candidate releases marked with the suffix ``.rc#``. * Development releases marked with the suffix ``.dev#``. * Version ordering (as recognized by pip & setuptools):: 0.5.dev0 < 0.5.dev1 < 0.5.dev5 < 0.5.a0.dev0 < 0.5.a0.dev5 < 0.5.a0 < 0.5.a3.dev0 < 0.5.a3.dev5 < 0.5.a3 < 0.5.b0.dev0 < 0.5.b0.dev5 < 0.5.b0 < 0.5.b3.dev0 < 0.5.b3.dev5 < 0.5.b3 < 0.5.rc0.dev0 < 0.5.rc0.dev5 < 0.5.rc0 < 0.5.rc3.dev0 < 0.5.rc3.dev5 < 0.5.rc3 < 0.5 < 0.5.1.dev0 < ... ... < 0.5.1 < 0.6.dev0 < ... ... < 0.6 < 1.0.dev0 < ... ... < 1.0 4. Tag in Hg. * Name the tag like ``release-``, e.g. ``release-0.5``. 5. Prepare official releases based only on tagged commits. * Official releases should always be prepared based on tagged revisions with no local changes in the used sandbox. * Prepare source distribution packages (both .zip & .tar.bz2 formats) and upload the prepared source packages to PyPI. * Run ``setup.py sdist upload``. * Prepare wheel packages for Python 2 & 3 using the latest Python 2 & 3 environments with the ``wheel`` package installed and upload them to PyPI. * Run ``setup.py bdist_wheel upload`` using both Python 2 & 3. * Upload the prepared source & wheel packages to the project site. * Use the BitBucket project web interface. 6. Next development version identification. * If this was a development release. * Bump up the existing ``.dev#`` suffix, e.g. change ``0.8.dev2`` to ``0.8.dev3``. * If this was a non-development release. * Bump up the forked project version counter (may add/remove/bump alfa/beta/release-candidate mark suffixes as needed). * Add the ``.dev0`` suffix, e.g. as in ``0.8.dev0``. 7. Notify whomever the new release might concern. DEVELOPMENT & TESTING ENVIRONMENT ================================================= In all command-line examples below pyX, pyXY & pyXYZ represent a Python interpreter executable for a specific Python version X, X.Y & X.Y.Z respectively. Setting up the development & testing environment ------------------------------------------------ ``tools/setup_base_environments.py`` script should be used for setting up the basic Python environments so they support testing our project. The script can be configured from the main project Python configuration file ``setup.cfg``. It implements all the backward compatibility tweaks and performs additional required package installation that would otherwise need to be done manually in order to be able to test our project in those environments. These exact requirements and their related version specific tweaks are not documented elsewhere so anyone interested in the details should consult the script's sources. The testing environment is generally set up as follows: 1. Install clean target Python environments. #. Update the project's ``setup.py`` configuration with information on your installed Python environments. #. Run the ``tools/setup_base_environments.py`` script. Some older Python environments may have slight issues caused by varying support levels in different used Python packages, but the basic testing functionality has been tested to make sure it works on as wide array of supported platforms as possible. Examples of such issues: * Colors not getting displayed on a Windows console terminal, with possibly ANSI color code escape sequences getting displayed instead. * ``pip`` utility can not be run from the command-line using the ``py -m pip`` syntax for some older versions. In such cases use the more portable ``py -c "import pip;pip.main()"`` syntax instead. * Some specific older Python versions (e.g. 2.4.3) have no SSL support and so have to reuse installations downloaded by other Python versions. Running the project tests - ``tools/run_all_tests.py`` script ------------------------------------------------------------- ``tools/run_all_tests.py`` script is a basic *poor man's tox* development script that can be used for running the full project test suite using multiple Python interpreter versions on a development machine. Intended to be replaced by a more portable ``tox`` based or similar automated testing solution some time in the future. Can be configured by tweaking the main project Python configuration file ``setup.cfg``: * List of target Python environments. * Each target Python environment's invocation command. Requires the target Python environment already be set up, and all the packages required for running the project test suite installed. See the `Setting up the development & testing environment`_ section for more detailed information. Automatically installs the project in editable mode in all tested Python environments. Caveats: * This method does not allow you to provide any extra ``pytest`` options when running the project test suite. Running the project tests - ``setup.py test`` command ----------------------------------------------------- Project tests can also be run for a specific Python environment by running the project's ``setup.py`` script in that environment and invoking its ``test`` command. E.g. run a command like one of the following ones from the top level project folder:: py243 setup.py test py27 setup.py test py3 setup.py test Note that the ``setup.py`` script always needs to be called from the top level project folder. For most Python versions, the target Python environment needs not be set up prior to running this command. Where possible (e.g. not for Python 2.4.x or 3.1.x versions), any missing testing requirements will be installed automatically, but not directly into the target environment but in the current folder instead. This functionality should be considered a band-aid though, and setting up the target environment can be better done as described in the `Setting up the development & testing environment`_ section. The ``setup.py test`` command will build the project if needed and run its test suite in the target Python environment. The project does not need to be preinstalled into the target Python environment for this operation to work, and neither will the operation leave it installed. Unless a more restricted test set is selected using ``pytest`` specific command-line options, ``setup.py test`` command runs the complete project test suite. Specific ``pytest`` command-line options may be provided by passing them all as a single whitespace separated string tunnelled via the ``setup.py test`` command's ``--pytest-args``/``-a`` command-line option. For example, the following command will run only tests containing ``binding`` in their name, will stop on first failure and will automatically drop into Python's post-mortem debugger on failure:: setup.py test -a "-k binding -x --pdb" Caveats: * This method does not currently allow passing ``pytest`` specific command-line options containing embedded whitespace. * When running the ``setup.py test`` command in a Windows Python 2.5 environment without an included ctypes module (e.g. 64-bit CPython 2.5 distribution does not include ctypes) and having it automatically install the colorama package version older than 0.1.11, you will get benign error messages reporting colorama's atexit handlers failing. Running the same command again avoids the issue since the colorama package will then already be installed. Suggested workaround is to use a colorama package version 0.3.2 or newer. Running the project tests - using ``pytest`` directly ----------------------------------------------------- To have greater control over the test suite and be able to specify additional ``pytest`` options on the command-line, or be able to run the tests on a different project installation (e.g. official release installed directly from PyPI), do the following: 1. Install the project into the target Python environment. * Installing the project can be done by either installing it directly into the target Python environment using one of the following commands (paths used assume the commands are being run from the top level project folder):: setup.py install easy_install . pip install . Or the project can be installed in editable mode using one of the following commands (so it does not need to be reinstalled after every source code change):: setup.py develop easy_install -e . pip install -e . * The installation step can be skipped if running Python 2 based project tests, and doing so from the top level project folder. 2. Run tests using ``pytest``. * If using Python 2.x: * Run ``pytest`` from the project's top level or ``tests`` folder:: py2 -m pytest * If using Python 3.x: * Since the project uses py2to3 source conversion, you need to build the project in order to generate the project's Python 3 sources before they can be tested. If the project has been installed in editable mode, then simply run the following from the top level project folder:: setup.py build and if it has not then rebuild and reinstall it using one of the following commands:: setup.py develop setup.py install Note that you might need to manually remove the build folder in order to have its contents regenerated when wanting to run the test suite using a different Python 3.x interpreter version, as those sources are regenerated based solely on the original & processed source file timestamp information and not the Python version used to process them. * Run ``pytest`` from the the project's ``tests`` folder:: py3 -m pytest Each specific test module can also be run directly as a script. Notes on the folder from which to run the tests: * When running tests from a folder other than the top level project folder, the tested project version needs to first be installed in the used Python environment. * Python 2 tests can be run from the top level project folder, in which case they will work even if the project has not been explicitly installed in the used Python environment. And even if another project version has been installed into the used Python environment, that one will be ignored and the one in the current folder used instead. * Python 3 tests can not be run from the top level project folder or they would attempt and fail to use Python 2 based project sources found in the current folder. See the ``pytest`` documentation for a detailed list of available command-line options. Some interesting ones: -l show local variable state in tracebacks --tb=short shorter traceback information for each failure -x stop on first failure --pdb enter Python debugger on failure Setting up multiple parallel Python interpreter versions on Windows ------------------------------------------------------------------- On Windows you might have a problem setting up multiple parallel Python interpreter versions in case their major and minor version numbers match, e.g. Python 2.4.3 & 2.4.4. In those cases, standard Windows installer will automatically remove the previous installation instead of simply adding a new one. In order to achieve such parallel setup we suggest the following steps: 1. Install the first version in a dummy folder, and do so for the current user only. #. Copy the dummy target folder to the desired folder for the first installation, e.g. Python243. #. Uninstall the original version. #. Set up a shortcut or a batch script (e.g. py243.cmd) for running this interpreter without having to have it added to the system path. #. Repeat the steps for the second installation. Installing Python for the current user only is necessary in order to make Python install all of its files into the target folder and not move some of them into shared system folders. Note that this will leave you without start menu or registry entries for these Python installations. Registry entries should be needed only if you want to run some external Python package installation tool requiring those entries in order to determine where to install its package data. In that case you can set those entries manually, e.g. by using a script similar to the one found at ``_. PYTHON 2/3 SOURCE CODE COMPATIBILITY ================================================= These are notes related to maintaining Python 2/3 source code compatibility in parts of this project that require it. Use the ``six `` Python 2/3 compatibility support package to make the compatibility patches simpler. Where a solution provided by ``six`` can not be used, explicitly explain the reason why in a related code comment. Do not use ``u"..."`` Python unicode literals since we wish to support Python 3.1 & 3.2 versions which do not support them. Useful site for easily converting unicode strings to their ``unicode-escape`` encoded representation which can then be used with the ``six.u()`` helper function: http://www.rapidmonkey.com/unicodeconverter EXTERNAL DOCUMENTATION ================================================= * SOAP * http://www.w3.org/TR/soap * Version 1.1. * http://www.w3.org/TR/2000/NOTE-SOAP-20000508 * Version 1.2. * Part0: Primer * http://www.w3.org/TR/2007/REC-soap12-part0-20070427 * Errata: http://www.w3.org/2007/04/REC-soap12-part0-20070427-errata.html * Part1: Messaging Framework * http://www.w3.org/TR/2007/REC-soap12-part1-20070427 * Errata: http://www.w3.org/2007/04/REC-soap12-part1-20070427-errata.html * Part2: Adjuncts * http://www.w3.org/TR/2007/REC-soap12-part2-20070427 * Errata: http://www.w3.org/2007/04/REC-soap12-part2-20070427-errata.html * Specification Assertions and Test Collection * http://www.w3.org/TR/2007/REC-soap12-testcollection-20070427 * Errata: http://www.w3.org/2007/04/REC-soap12-testcollection-20070427-errata.html * WS-I Basic Profile 1.1 * http://www.ws-i.org/Profiles/BasicProfile-1.1.html * WSDL 1.1 * http://www.w3.org/TR/wsdl * XML Schema * Part 0: Primer Second Edition - http://www.w3.org/TR/xmlschema-0 * Non-normative document intended to provide an easily readable description of the XML Schema facilities, and is oriented towards quickly understanding how to create schemas using the XML Schema language. * Part 1: Structures - http://www.w3.org/TR/xmlschema-1 * Part 2: Datatypes - http://www.w3.org/TR/xmlschema-2 STANDARDS CONFORMANCE ================================================= There seems to be no complete standards conformance overview for the suds project. This section contains just some related notes, taken down while hacking on this project. As more related information is uncovered, it should be added here as well, and eventually this whole section should be moved to the project's user documentation. Interpreting message parts defined by a WSDL schema --------------------------------------------------- * Each message part is interpreted as a single parameter. * What we refer to here as a 'parameter' may not necessarily correspond 1-1 to a Python function argument passed when using the suds library's Python function interface for invoking web service operations. In some cases suds may attempt to make the Python function interfaces more intuitive to the user by automatically unwrapping a parameter as defined inside a WSDL schema into multiple Python function arguments. * In order to achieve interoperability with existing software 'in the wild', suds does not fully conform to the WSDL 1.1 specification with regard as to how message parts are mapped to input data contained in SOAP XML web service operation invocation request documents. * WSDL 1.1 standard states: * 2.3.1 Message Parts. * A message may have message parts referencing either an element or a type defined in the WSDL's XSD schema. * If a message has a message part referencing a type defined in the WSDL's XSD schema, then that must be its only message part. * 3.5 soap:body. * If using document/literal binding and a message has a message part referencing a type defined in the WSDL's XSD schema then that part becomes the schema type of the enclosing SOAP envelope Body element. * Suds supports multiple message parts, each of which may be related either to an element or a type. * Suds uses message parts related to types, as if they were related to an element, using the message part name as the representing XML element name in the constructed related SOAP XML web service operation invocation request document. * WS-I Basic Profile 1.1 standard explicitly avoids the issue by stating the following: * R2204 - A document/literal binding in a DESCRIPTION MUST refer, in each of its soapbind:body element(s), only to wsdl:part element(s) that have been defined using the element attribute. * Rationale. * No other software has been encountered implementing the exact functionality specified in the WSDL 1.1 standard. * Already done in the original suds implementation. * Example software whose implementation matches our own. * SoapUI. * Tested with version 4.6.1. * WSDL analyzer & invoker at ``_. WSDL XSD schema interpretation ------------------------------ * ``minOccurs``/``maxOccurs`` attributes on ``all``, ``choice`` & ``sequence`` schema elements are ignored. * Rationale. * Already done in the original suds implementation. * Extra notes. * SoapUI (tested with version 4.6.1). * For ``all``, ``choice`` & ``sequence`` schema elements with their ``minOccurs`` attribute set to "0", does not explicitly mark elements found in such containers as optional. * Supports sending multiple same-named web service operation parameters, but only if they are specified next to each other in the constructed web service operation invocation request document. * Done by passing a list or tuple of such values to the suds constructed Python function representing the web service operation in question. * Rationale. * Already done in the original suds implementation. * Extra notes. * Such same-named values break other web service related tools as well, e.g. WSDL analyzer & invoker at ``_. PROJECT IMPLEMENTATION NOTES ================================================= Sometimes we have a reason for implementing a feature in a certain way that may not be obvious at first and which thus deserves an implementation comment explaining the rationale behind it. In cases when such rationale would then be duplicated at different places in code, and project implementation note should be added and identified here, and its respective implementation locations marked using a comment such as:: # See 'Project implementation note #42'. Project implementation note #1 ------------------------------- ``pytest`` test parametrizations must be defined so they get ordered the same in different test processes. Doing otherwise may confuse the ``pytest`` ``xdist`` plugin used for running parallel tests using multiple test processes (last tested using ``pytest 2.5.2``, ``xdist 1.10`` & ``execnet 1.2.0``) and may cause it to exit with errors such as:: AssertionError: Different tests were collected between gw1 and gw0 Specifically, this means that ``pytest`` test parametrizations should not be constructed using iteration over unordered collections such as sets or dictionaries, at least not with Python's hash randomization feature enabled (implemented as optional since Python 2.6.8, enabled by default since Python 3.3). See the following ``pytest`` issues for more detailed information: * `#301 `_ - serializing collection process (per host) on xdist to avoid conflicts/collection errors * `#437 `_ - different tests collected on two nodes with xdist REPRODUCING PROBLEMATIC USE CASES ================================================= Failing web service processing examples can be easily packaged as reproducible test cases using the suds library 'message & reply injection' technique. Some things you can achieve using this technique (for examples, see existing project unit tests): * Create a client object based on a fixed WSDL string. * Have a client object send a fixed request string without having it construct one based on the loaded WSDL schema and received arguments. * Have a client object process a fixed reply string without having it send a request to an actual external web service.