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diff --git a/docs/quick_tutorial/routing.rst b/docs/quick_tutorial/routing.rst new file mode 100644 index 000000000..27c8c2c22 --- /dev/null +++ b/docs/quick_tutorial/routing.rst @@ -0,0 +1,124 @@ +.. _qtut_routing: + +========================================== +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://static.repoze.org/casts/videotags.html>`_ 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 + + $ cd ..; cp -r view_classes routing; cd routing + $ $VENV/bin/pip install -e . + +#. 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 + + $ $VENV/bin/$VENV/bin/py.test tutorial/tests.py -q + .. + 2 passed in 0.39 seconds + +#. Run your Pyramid application with: + + .. code-block:: bash + + $ $VENV/bin/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:`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>`_ |
