diff options
Diffstat (limited to 'docs/quick_tutorial/routing.rst')
| -rw-r--r-- | docs/quick_tutorial/routing.rst | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/docs/quick_tutorial/routing.rst b/docs/quick_tutorial/routing.rst new file mode 100644 index 000000000..39597d996 --- /dev/null +++ b/docs/quick_tutorial/routing.rst @@ -0,0 +1,119 @@ +========================================== +11: Dispatching URLs To Views With Routing +========================================== + +Routing matches incoming URL patterns to view code. Pyramid's routing +has a number of useful features. + +Background +========== + +Writing web applications usually means sophisticated URL design. We +just saw some Pyramid machinery for requests and views. Let's look at +features that help in routing. + +Previously we saw the basics of routing URLs to views in Pyramid: + +- Your project's "setup" code registers a route name to be used when + matching part of the URL + +- Elsewhere, a view is configured to be called for that route name + +.. note:: + + Why do this twice? Other Python web frameworks let you create a + route and associate it with a view in one step. As + illustrated in :ref:`routes_need_ordering`, multiple routes might match the + same URL pattern. Rather than provide ways to help guess, Pyramid lets you + be explicit in ordering. Pyramid also gives facilities to avoid the + problem. It's relatively easy to build a system that uses implicit route + ordering with Pyramid too. See `The Groundhog series of screencasts + <http://bfg.repoze.org/videos#groundhog1>`_ if you're interested in + doing so. + +Objectives +========== + +- Define a route that extracts part of the URL into a Python dictionary + +- Use that dictionary data in a view + +Steps +===== + +#. First we copy the results of the ``view_classes`` step: + + .. code-block:: bash + + (env27)$ cd ..; cp -r view_classes routing; cd routing + (env27)$ python setup.py develop + +#. Our ``routing/tutorial/__init__.py`` needs a route with a replacement + pattern: + + .. literalinclude:: routing/tutorial/__init__.py + :linenos: + +#. We just need one view in ``routing/tutorial/views.py``: + + .. literalinclude:: routing/tutorial/views.py + :linenos: + +#. We just need one view in ``routing/tutorial/home.pt``: + + .. literalinclude:: routing/tutorial/home.pt + :language: html + :linenos: + +#. Update ``routing/tutorial/tests.py``: + + .. literalinclude:: routing/tutorial/tests.py + :linenos: + +#. Now run the tests: + + .. code-block:: bash + + (env27)$ nosetests tutorial + +#. Run your Pyramid application with: + + .. code-block:: bash + + (env27)$ pserve development.ini --reload + +#. Open ``http://localhost:6543/howdy/amy/smith`` in your browser. + +Analysis +======== + +In ``__init__.py`` we see an important change in our route declaration: + +.. code-block:: python + + config.add_route('hello', '/howdy/{first}/{last}') + +With this we tell the :term:`pyramid:configurator` that our URL has +a "replacement pattern". With this, URLs such as ``/howdy/amy/smith`` +will assign ``amy`` to ``first`` and ``smith`` to ``last``. We can then +use this data in our view: + +.. code-block:: python + + self.request.matchdict['first'] + self.request.matchdict['last'] + +``request.matchdict`` contains values from the URL that match the +"replacement patterns" (the curly braces) in the route declaration. +This information can then be used anywhere in Pyramid that has access +to the request. + +Extra Credit +============ + +#. What happens if you to go the URL + ``http://localhost:6543/howdy``? Is this the result that you + expected? + +.. seealso:: `Weird Stuff You Can Do With URL + Dispatch <http://www.plope.com/weird_pyramid_urldispatch>`_ |
