.. -*- coding: utf-8 -*-

Tests

=====

Unit tests

----------

The *CubicWeb* framework provides the

:class:`cubicweb.devtools.testlib.CubicWebTC` test base class .

Tests shall be put into the mycube/test directory. Additional test

data shall go into mycube/test/data.

It is much advised to write tests concerning entities methods,

actions, hooks and operations, security. The

:class:`~cubicweb.devtools.testlib.CubicWebTC` base class has

convenience methods to help test all of this.

In the realm of views, automatic tests check that views are valid

XHTML. See :ref:`automatic_views_tests` for details.

Most unit tests need a live database to work against. This is achieved

by CubicWeb using automatically sqlite (bundled with Python, see

http://docs.python.org/library/sqlite3.html) as a backend.

The database is stored in the mycube/test/tmpdb,

mycube/test/tmpdb-template files. If it does not (yet) exists, it will

be built automatically when the test suit starts.

.. warning::

  Whenever the schema changes (new entities, attributes, relations)

  one must delete these two files. Changes concerned only with entity

  or relation type properties (constraints, cardinalities,

  permissions) and generally dealt with using the

  `sync_schema_props_perms()` fonction of the migration environment

  need not a database regeneration step.

.. _hook_test:

Unit test by example

````````````````````

We start with an example extracted from the keyword cube (available

from http://www.cubicweb.org/project/cubicweb-keyword).

.. sourcecode:: python

    from cubicweb.devtools.testlib import CubicWebTC

    from cubicweb import ValidationError

    class ClassificationHooksTC(CubicWebTC):

        def setup_database(self):

            req = self.request()

            group_etype = req.find_one_entity('CWEType', name='CWGroup')

            c1 = req.create_entity('Classification', name=u'classif1',

                                   classifies=group_etype)

            user_etype = req.find_one_entity('CWEType', name='CWUser')

            c2 = req.create_entity('Classification', name=u'classif2',

                                   classifies=user_etype)

            self.kw1 = req.create_entity('Keyword', name=u'kwgroup', included_in=c1)

            self.kw2 = req.create_entity('Keyword', name=u'kwuser', included_in=c2)

        def test_cannot_create_cycles(self):

            # direct obvious cycle

            self.assertRaises(ValidationError, self.kw1.cw_set,

                              subkeyword_of=self.kw1)

            # testing indirect cycles

            kw3 = self.execute('INSERT Keyword SK: SK name "kwgroup2", SK included_in C, '

                               'SK subkeyword_of K WHERE C name "classif1", K eid %s'

                               % self.kw1.eid).get_entity(0,0)

            self.kw1.cw_set(subkeyword_of=kw3)

            self.assertRaises(ValidationError, self.commit)

The test class defines a :meth:`setup_database` method which populates the

database with initial data. Each test of the class runs with this

pre-populated database. A commit is done automatically after the

:meth:`setup_database` call. You don't have to call it explicitely.

The test case itself checks that an Operation does it job of

preventing cycles amongst Keyword entities.

`create_entity` is a useful method, which easily allows to create an

entity. You can link this entity to others entities, by specifying as

argument, the relation name, and the entity to link, as value. In the

above example, the `Classification` entity is linked to a `CWEtype`

via the relation `classifies`. Conversely, if you are creating a

`CWEtype` entity, you can link it to a `Classification` entity, by

adding `reverse_classifies` as argument.

.. note::

   :meth:`commit` method is not called automatically in test_XXX

   methods. You have to call it explicitely if needed (notably to test

   operations). It is a good practice to call :meth:`clear_all_caches`

   on entities after a commit to avoid request cache effects.

You can see an example of security tests in the

:ref:`adv_tuto_security`.

It is possible to have these tests run continuously using `apycot`_.

.. _apycot: http://www.logilab.org/project/apycot

.. _securitytest:

Managing connections or users

+++++++++++++++++++++++++++++

Since unit tests are done with the SQLITE backend and this does not

support multiple connections at a time, you must be careful when

simulating security, changing users.

By default, tests run with a user with admin privileges. This

user/connection must never be closed.

Before a self.login, one has to release the connection pool in use

with a self.commit, self.rollback or self.close.

The `login` method returns a connection object that can be used as a

context manager:

.. sourcecode:: python

   with self.login('user1') as user:

       req = user.req

       req.execute(...)

On exit of the context manager, either a commit or rollback is issued,

which releases the connection.

When one is logged in as a normal user and wants to switch back to the

admin user without committing, one has to use

self.restore_connection().

Usage with restore_connection:

.. sourcecode:: python

    # execute using default admin connection

    self.execute(...)

    # I want to login with another user, ensure to free admin connection pool

    # (could have used rollback but not close here

    # we should never close defaut admin connection)

    self.commit()

    cnx = self.login('user')

    # execute using user connection

    self.execute(...)

    # I want to login with another user or with admin user

    self.commit();  cnx.close()

    # restore admin connection, never use cnx = self.login('admin'), it will return

    # the default admin connection and one may be tempted to close it

    self.restore_connection()

.. warning::

   Do not use the references kept to the entities created with a

   connection from another !

Email notifications tests

`````````````````````````

When running tests potentially generated e-mails are not really sent

but is found in the list `MAILBOX` of module

:mod:`cubicweb.devtools.testlib`.

You can test your notifications by analyzing the contents of this list, which

contains objects with two attributes:

* `recipients`, the list of recipients

* `msg`, object email.Message

Let us look at simple example from the ``blog`` cube.

.. sourcecode:: python

    from cubicweb.devtools.testlib import CubicWebTC, MAILBOX

    class BlogTestsCubicWebTC(CubicWebTC):

        """test blog specific behaviours"""

        def test_notifications(self):

            req = self.request()

            cubicweb_blog = req.create_entity('Blog', title=u'cubicweb',

                                description=u'cubicweb is beautiful')

            blog_entry_1 = req.create_entity('BlogEntry', title=u'hop',

                                             content=u'cubicweb hop')

            blog_entry_1.cw_set(entry_of=cubicweb_blog)

            blog_entry_2 = req.create_entity('BlogEntry', title=u'yes',

                                             content=u'cubicweb yes')

            blog_entry_2.cw_set(entry_of=cubicweb_blog)

            self.assertEqual(len(MAILBOX), 0)

            self.commit()

            self.assertEqual(len(MAILBOX), 2)

            mail = MAILBOX[0]

            self.assertEqual(mail.subject, '[data] hop')

            mail = MAILBOX[1]

            self.assertEqual(mail.subject, '[data] yes')

Visible actions tests

`````````````````````

It is easy to write unit tests to test actions which are visible to

user or to a category of users. Let's take an example in the

`conference cube`_.

.. _`conference cube`: http://www.cubicweb.org/project/cubicweb-conference

.. sourcecode:: python

    class ConferenceActionsTC(CubicWebTC):

        def setup_database(self):

            self.conf = self.create_entity('Conference',

                                           title=u'my conf',

                                           url_id=u'conf',

                                           start_on=date(2010, 1, 27),

                                           end_on = date(2010, 1, 29),

                                           call_open=True,

                                           reverse_is_chair_at=chair,

                                           reverse_is_reviewer_at=reviewer)

        def test_admin(self):

            req = self.request()

            rset = req.find_entities('Conference')

            self.assertListEqual(self.pactions(req, rset),

                                  [('workflow', workflow.WorkflowActions),

                                   ('edit', confactions.ModifyAction),

                                   ('managepermission', actions.ManagePermissionsAction),

                                   ('addrelated', actions.AddRelatedActions),

                                   ('delete', actions.DeleteAction),

                                   ('generate_badge_action', badges.GenerateBadgeAction),

                                   ('addtalkinconf', confactions.AddTalkInConferenceAction)

                                   ])

            self.assertListEqual(self.action_submenu(req, rset, 'addrelated'),

                                  [(u'add Track in_conf Conference object',

                                    u'http://testing.fr/cubicweb/add/Track'

                                    u'?__linkto=in_conf%%3A%(conf)s%%3Asubject&'

                                    u'__redirectpath=conference%%2Fconf&'

                                    u'__redirectvid=' % {'conf': self.conf.eid}),

                                   ])

You just have to execute a rql query corresponding to the view you want to test,

and to compare the result of

:meth:`~cubicweb.devtools.testlib.CubicWebTC.pactions` with the list of actions

that must be visible in the interface. This is a list of tuples. The first

element is the action's `__regid__`, the second the action's class.

To test actions in submenu, you just have to test the result of

:meth:`~cubicweb.devtools.testlib.CubicWebTC.action_submenu` method. The last

parameter of the method is the action's category. The result is a list of

tuples. The first element is the action's title, and the second element the

action's url.

.. _automatic_views_tests:

Automatic views testing

-----------------------

This is done automatically with the :class:`cubicweb.devtools.testlib.AutomaticWebTest`

class. At cube creation time, the mycube/test/test_mycube.py file

contains such a test. The code here has to be uncommented to be

usable, without further modification.

The ``auto_populate`` method uses a smart algorithm to create

pseudo-random data in the database, thus enabling the views to be

invoked and tested.

Depending on the schema, hooks and operations constraints, it is not

always possible for the automatic auto_populate to proceed.

It is possible of course to completely redefine auto_populate. A

lighter solution is to give hints (fill some class attributes) about

what entities and relations have to be skipped by the auto_populate

mechanism. These are:

* `no_auto_populate`, may contain a list of entity types to skip

* `ignored_relations`, may contain a list of relation types to skip

* `application_rql`, may contain a list of rql expressions that

  auto_populate cannot guess by itself; these must yield resultsets

  against which views may be selected.

.. warning::

  Take care to not let the imported `AutomaticWebTest` in your test module

  namespace, else both your subclass *and* this parent class will be run.

Cache heavy database setup

-------------------------------

Some tests suite require a complex setup of the database that takes seconds (or

event minutes) to complete. Doing the whole setup for all individual tests make

the whole run very slow. The ``CubicWebTC`` class offer a simple way to prepare

specific database once for multiple tests. The `test_db_id` class attribute of

your ``CubicWebTC`` must be set a unique identifier and the

:meth:`pre_setup_database` class method build the cached content. As the

:meth:`pre_setup_database` method is not grantee to be called, you must not set

any class attribut to be used during test there.  Databases for each `test_db_id`

are automatically created if not already in cache.  Clearing the cache is up to

the user. Cache files are found in the :file:`data/database` subdirectory of your

test directory.

.. warning::

  Take care to always have the same :meth:`pre_setup_database` function for all

  call with a given `test_db_id` otherwise you test will have unpredictable

  result given the first encountered one.

Testing on a real-life database

-------------------------------

The ``CubicWebTC`` class uses the `cubicweb.devtools.ApptestConfiguration`

configuration class to setup its testing environment (database driver,

user password, application home, and so on). The `cubicweb.devtools`

module also provides a `RealDatabaseConfiguration`

class that will read a regular cubicweb sources file to fetch all

this information but will also prevent the database to be initalized

and reset between tests.

For a test class to use a specific configuration, you have to set

the `_config` class attribute on the class as in:

.. sourcecode:: python

    from cubicweb.devtools import RealDatabaseConfiguration

    from cubicweb.devtools.testlib import CubicWebTC

    class BlogRealDatabaseTC(CubicWebTC):

        _config = RealDatabaseConfiguration('blog',

                                            sourcefile='/path/to/realdb_sources')

        def test_blog_rss(self):

            req = self.request()

            rset = req.execute('Any B ORDERBY D DESC WHERE B is BlogEntry, '

                'B created_by U, U login "logilab", B creation_date D')

            self.view('rss', rset)

Testing with other cubes

------------------------

Sometimes a small component cannot be tested all by itself, so one

needs to specify other cubes to be used as part of the the unit test

suite. This is handled by the ``bootstrap_cubes`` file located under

``mycube/test/data``. One example from the `preview` cube::

 card, file, preview

The format is:

* possibly several empy lines or lines starting with ``#`` (comment lines)

* one line containing a coma separated list of cube names.

It is also possible to add a ``schema.py`` file in

``mycube/test/data``, which will be used by the testing framework,

therefore making new entity types and relations available to the

tests. 

Literate programming

--------------------

CubicWeb provides some literate programming capabilities. The :ref:`cubicweb-ctl`

`shell` command accepts differents format files. If your file ends with `.txt`

or `.rst`, the file will be parsed by :mod:`doctest.testfile` with CubicWeb

:ref:`migration` API enabled in it.

Create a `scenario.txt` file into `test/` directory and fill with some content.

Please refer the :mod:`doctest.testfile` `documentation`_.

.. _documentation: http://docs.python.org/library/doctest.html

Then, you can run it directly by::

    $ cubicweb-ctl shell <cube_instance> test/scenario.txt

When your scenario file is ready, put it in a new test case to be able to run

it automatically.

.. sourcecode:: python

      from os.path import dirname, join

      from logilab.common.testlib import unittest_main

      from cubicweb.devtools.testlib import CubicWebTC

      class AcceptanceTC(CubicWebTC):

              def test_scenario(self):

                      self.assertDocTestFile(join(dirname(__file__), 'scenario.txt'))

      if __name__ == '__main__':

              unittest_main()

Skipping a scenario

```````````````````

If you want to set up initial conditions that you can't put in your unit test

case, you have to use a :exc:`KeyboardInterrupt` exception only because of the

way :mod:`doctest` module will catch all the exceptions internally.

    >>> if condition_not_met:

    ...     raise KeyboardInterrupt('please, check your fixture.')

Passing paramaters

``````````````````

Using extra arguments to parametrize your scenario is possible by prepend them

by double dashes.

Please refer to the `cubicweb-ctl shell --help` usage.

.. important::

    Your scenario file must be utf-8 encoded.

Test APIS

---------

Using Pytest

````````````

The `pytest` utility (shipping with `logilab-common`_, which is a

mandatory dependency of CubicWeb) extends the Python unittest

functionality and is the preferred way to run the CubicWeb test

suites. Bare unittests also work the usual way.

.. _logilab-common: http://www.logilab.org/project/logilab-common

To use it, you may:

* just launch `pytest` in your cube to execute all tests (it will

  discover them automatically)

* launch `pytest unittest_foo.py` to execute one test file

* launch `pytest unittest_foo.py bar` to execute all test methods and

  all test cases whose name contain `bar`