doc/book/annexes/rql/debugging.rst
author Philippe Pepiot <philippe.pepiot@logilab.fr>
Tue, 07 Feb 2017 13:47:03 +0100
changeset 11955 f85ec84355db
parent 10491 c67bcee93248
child 12716 f5300acd8f4f
permissions -rw-r--r--
Fix possible double import of cubes modules When cubes using the new layout are imported with 'cubicweb_<cube>' and with 'cubes.<cube>', the same module is imported twice. Handle this by adding 'cubes.<cube>' to sys.modules when importing from 'cubicweb_<cube>'. Move load_module() to a sub class _CubesLoader to share informations computed in find_modules(). Don't handle subpackages in _CubesImporter and rely on normal import machinery instead. Add a test and use unittest from cubicweb.devtools.testlib which resolve to unittest2 on PY2 with assertLogs() method.

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

.. _DEBUGGING:

Debugging RQL
-------------

Available levels
~~~~~~~~~~~~~~~~

Server debugging flags. They may be combined using binary operators.

.. autodata:: cubicweb.server.DBG_NONE
.. autodata:: cubicweb.server.DBG_RQL
.. autodata:: cubicweb.server.DBG_SQL
.. autodata:: cubicweb.server.DBG_REPO
.. autodata:: cubicweb.server.DBG_MS
.. autodata:: cubicweb.server.DBG_HOOKS
.. autodata:: cubicweb.server.DBG_OPS
.. autodata:: cubicweb.server.DBG_MORE
.. autodata:: cubicweb.server.DBG_ALL


Enable verbose output
~~~~~~~~~~~~~~~~~~~~~

To debug your RQL statements, it can be useful to enable a verbose output:

.. sourcecode:: python

    from cubicweb import server
    server.set_debug(server.DBG_RQL|server.DBG_SQL|server.DBG_ALL)

.. autofunction:: cubicweb.server.set_debug

Another example showing how to debug hooks at a specific code site:

.. sourcecode:: python

    from cubicweb.server import debugged, DBG_HOOKS
    with debugged(DBG_HOOKS):
        person.cw_set(works_for=company)


Detect largest RQL queries
~~~~~~~~~~~~~~~~~~~~~~~~~~~

See `Profiling and performance` chapter (see :ref:`PROFILING`).


API
~~~

.. autoclass:: cubicweb.server.debugged