.. _command_line_chapter: Command-Line Pyramid ==================== Your :app:`Pyramid` application can be controlled and inspected using a variety of command-line utilities. These utilities are documented in this chapter. .. index:: pair: matching views; printing single: paster pviews .. _displaying_matching_views: Displaying Matching Views for a Given URL ----------------------------------------- For a big application with several views, it can be hard to keep the view configuration details in your head, even if you defined all the views yourself. You can use the ``paster pviews`` command in a terminal window to print a summary of matching routes and views for a given URL in your application. The ``paster pviews`` command accepts two arguments. The first argument to ``pviews`` is the path to your application's ``.ini`` file and section name inside the ``.ini`` file which points to your application. This should be of the format ``config_file#section_name``. The second argument is the URL to test for matching views. The ``section_name`` may be omitted; if it is, it's considered to be ``main``. Here is an example for a simple view configuration using :term:`traversal`: .. code-block:: text :linenos: $ ../bin/paster pviews development.ini#tutorial /FrontPage URL = /FrontPage context: view name: View: ----- tutorial.views.view_page required permission = view The output always has the requested URL at the top and below that all the views that matched with their view configuration details. In this example only one view matches, so there is just a single *View* section. For each matching view, the full code path to the associated view callable is shown, along with any permissions and predicates that are part of that view configuration. A more complex configuration might generate something like this: .. code-block:: text :linenos: $ ../bin/paster pviews development.ini#shootout /about URL = /about context: view name: about Route: ------ route name: about route pattern: /about route path: /about subpath: route predicates (request method = GET) View: ----- shootout.views.about_view required permission = view view predicates (request_param testing, header X/header) Route: ------ route name: about_post route pattern: /about route path: /about subpath: route predicates (request method = POST) View: ----- shootout.views.about_view_post required permission = view view predicates (request_param test) View: ----- shootout.views.about_view_post2 required permission = view view predicates (request_param test2) In this case, we are dealing with a :term:`URL dispatch` application. This specific URL has two matching routes. The matching route information is displayed first, followed by any views that are associated with that route. As you can see from the second matching route output, a route can be associated with more than one view. For a URL that doesn't match any views, ``paster pviews`` will simply print out a *Not found* message. .. index:: single: interactive shell single: IPython single: paster pshell single: pshell .. _interactive_shell: The Interactive Shell --------------------- Once you've installed your program for development using ``setup.py develop``, you can use an interactive Python shell to execute expressions in a Python environment exactly like the one that will be used when your application runs "for real". To do so, use the ``paster pshell`` command. The argument to ``pshell`` follows the format ``config_file#section_name`` where ``config_file`` is the path to your application's ``.ini`` file and ``section_name`` is the ``app`` section name inside the ``.ini`` file which points to your application. For example, if your application ``.ini`` file might have a ``[app:main]`` section that looks like so: .. code-block:: ini :linenos: [app:main] use = egg:MyProject pyramid.reload_templates = true pyramid.debug_authorization = false pyramid.debug_notfound = false pyramid.debug_templates = true pyramid.default_locale_name = en If so, you can use the following command to invoke a debug shell using the name ``MyProject`` as a section name: .. code-block:: text chrism@thinko env26]$ bin/paster pshell starter/development.ini#MyProject Python 2.6.5 (r265:79063, Apr 29 2010, 00:31:32) [GCC 4.4.3] on linux2 Type "help" for more information. Environment: app The WSGI application. registry Active Pyramid registry. request Active request object. root Root of the default resource tree. root_factory Default root factory used to create `root`. >>> root >>> registry >>> registry.settings['pyramid.debug_notfound'] False >>> from myproject.views import my_view >>> from pyramid.request import Request >>> r = Request.blank('/') >>> my_view(r) {'project': 'myproject'} The WSGI application that is loaded will be available in the shell as the ``app`` global. Also, if the application that is loaded is the :app:`Pyramid` app with no surrounding middleware, the ``root`` object returned by the default :term:`root factory`, ``registry``, and ``request`` will be available. You can also simply rely on the ``main`` default section name by omitting any hash after the filename: .. code-block:: text chrism@thinko env26]$ bin/paster pshell starter/development.ini Press ``Ctrl-D`` to exit the interactive shell (or ``Ctrl-Z`` on Windows). .. index:: pair: pshell; extending .. _extending_pshell: Extending the Shell ~~~~~~~~~~~~~~~~~~~ It is convenient when using the interactive shell often to have some variables significant to your application already loaded as globals when you start the ``pshell``. To facilitate this, ``pshell`` will look for a special ``[pshell]`` section in your INI file and expose the subsequent key/value pairs to the shell. Each key is a variable name that will be global within the pshell session; each value is a :term:`dotted Python name`. If specified, the special key ``setup`` should be a :term:`dotted Python name` pointing to a callable that accepts the dictionary of globals that will be loaded into the shell. This allows for some custom initializing code to be executed each time the ``pshell`` is run. The ``setup`` callable can also be specified from the commandline using the ``--setup`` option which will override the key in the INI file. For example, you want to expose your model to the shell, along with the database session so that you can mutate the model on an actual database. Here, we'll assume your model is stored in the ``myapp.models`` package. .. code-block:: ini :linenos: [pshell] setup = myapp.lib.pshell.setup m = myapp.models session = myapp.models.DBSession t = transaction By defining the ``setup`` callable, we will create the module ``myapp.lib.pshell`` containing a callable named ``setup`` that will receive the global environment before it is exposed to the shell. Here we mutate the environment's request as well as add a new value containing a WebTest version of the application to which we can easily submit requests. .. code-block:: python :linenos: # myapp/lib/pshell.py from webtest import TestApp def setup(env): env['request'].host = 'www.example.com' env['request'].scheme = 'https' env['testapp'] = TestApp(env['app']) When this INI file is loaded, the extra variables ``m``, ``session`` and ``t`` will be available for use immediately. Since a ``setup`` callable was also specified, it is executed and a new variable ``testapp`` is exposed, and the request is configured to generate urls from the host ``http://www.example.com``. For example: .. code-block:: text chrism@thinko env26]$ bin/paster pshell starter/development.ini Python 2.6.5 (r265:79063, Apr 29 2010, 00:31:32) [GCC 4.4.3] on linux2 Type "help" for more information. Environment: app The WSGI application. registry Active Pyramid registry. request Active request object. root Root of the default resource tree. root_factory Default root factory used to create `root`. testapp Custom Variables: m myapp.models session myapp.models.DBSession t transaction >>> testapp.get('/') <200 OK text/html body='\n'/3337> >>> request.route_url('home') 'https://www.example.com/' .. index:: single: IPython IPython ~~~~~~~ If you have `IPython `_ installed in the interpreter you use to invoke the ``paster`` command, the ``pshell`` command will use an IPython interactive shell instead of a standard Python interpreter shell. If you don't want this to happen, even if you have IPython installed, you can pass the ``--disable-ipython`` flag to the ``pshell`` command to use a standard Python interpreter shell unconditionally. .. code-block:: text [chrism@vitaminf shellenv]$ ../bin/paster pshell --disable-ipython \ development.ini#MyProject .. index:: pair: routes; printing single: paster proutes single: proutes .. _displaying_application_routes: Displaying All Application Routes --------------------------------- You can use the ``paster proutes`` command in a terminal window to print a summary of routes related to your application. Much like the ``paster pshell`` command (see :ref:`interactive_shell`), the ``paster proutes`` command accepts one argument with the format ``config_file#section_name``. The ``config_file`` is the path to your application's ``.ini`` file, and ``section_name`` is the ``app`` section name inside the ``.ini`` file which points to your application. By default, the ``section_name`` is ``main`` and can be omitted. For example: .. code-block:: text :linenos: [chrism@thinko MyProject]$ ../bin/paster proutes development.ini#MyProject Name Pattern View ---- ------- ---- home / home2 / another /another None static/ static/*subpath catchall /*subpath ``paster proutes`` generates a table. The table has three columns: a Name column, a Pattern column, and a View column. The items listed in the Name column are route names, the items listed in the Pattern column are route patterns, and the items listed in the View column are representations of the view callable that will be invoked when a request matches the associated route pattern. The view column may show ``None`` if no associated view callable could be found. If no routes are configured within your application, nothing will be printed to the console when ``paster proutes`` is executed. .. index:: pair: tweens; printing single: paster ptweens single: ptweens .. _displaying_tweens: Displaying "Tweens" ------------------- A :term:`tween` is a bit of code that sits between the main Pyramid application request handler and the WSGI application which calls it. A user can get a representation of both the implicit tween ordering (the ordering specified by calls to :meth:`pyramid.config.Configurator.add_tween`) and the explicit tween ordering (specified by the ``pyramid.tweens`` configuration setting) orderings using the ``paster ptweens`` command. Tween factories will show up represented by their standard Python dotted name in the ``paster ptweens`` output. For example, here's the ``paster pwteens`` command run against a system configured without any explicit tweens: .. code-block:: text :linenos: [chrism@thinko pyramid]$ paster ptweens development.ini "pyramid.tweens" config value NOT set (implicitly ordered tweens used) Implicit Tween Chain Position Name Alias -------- ---- ----- - - INGRESS 0 pyramid_debugtoolbar.toolbar.toolbar_tween_factory pdbt 1 pyramid.tweens.excview_tween_factory excview - - MAIN Here's the ``paster pwteens`` command run against a system configured *with* explicit tweens defined in its ``development.ini`` file: .. code-block:: text :linenos: [chrism@thinko pyramid]$ paster ptweens development.ini "pyramid.tweens" config value set (explicitly ordered tweens used) Explicit Tween Chain (used) Position Name -------- ---- - INGRESS 0 starter.tween_factory2 1 starter.tween_factory1 2 pyramid.tweens.excview_tween_factory - MAIN Implicit Tween Chain (not used) Position Name Alias -------- ---- ----- - - INGRESS 0 pyramid_debugtoolbar.toolbar.toolbar_tween_factory pdbt 1 pyramid.tweens.excview_tween_factory excview - - MAIN Here's the application configuration section of the ``development.ini`` used by the above ``paster ptweens`` command which reprorts that the explicit tween chain is used: .. code-block:: text :linenos: [app:main] use = egg:starter reload_templates = true debug_authorization = false debug_notfound = false debug_routematch = false debug_templates = true default_locale_name = en pyramid.include = pyramid_debugtoolbar pyramid.tweens = starter.tween_factory2 starter.tween_factory1 pyramid.tweens.excview_tween_factory See :ref:`registering_tweens` for more information about tweens. .. _writing_a_script: Writing a Script ---------------- All web applications are, at their hearts, systems which accept a request and return a response. When a request is accepted by a :app:`Pyramid` application, the system receives state from the request which is later relied on by your application code. For example, one :term:`view callable` may assume it's working against a request that has a ``request.matchdict`` of a particular composition, while another assumes a different composition of the matchdict. In the meantime, it's convenient to be able to write a Python script that can work "in a Pyramid environment", for instance to update database tables used by your :app:`Pyramid` application. But a "real" Pyramid environment doesn't have a completely static state independent of a request; your application (and Pyramid itself) is almost always reliant on being able to obtain information from a request. When you run a Python script that simply imports code from your application and tries to run it, there just is no request data, because there isn't any real web request. Therefore some parts of your application and some Pyramid APIs will not work. For this reason, :app:`Pyramid` makes it possible to run a script in an environment much like the environment produced when a particular :term:`request` reaches your :app:`Pyramid` application. This is achieved by using the :func:`pyramid.paster.bootstrap` command in the body of your script. .. note:: This feature is new as of :app:`Pyramid` 1.1. In the simplest case, :func:`pyramid.paster.bootstrap` can be used with a single argument, which accepts the :term:`PasteDeploy` ``.ini`` file representing Pyramid your application configuration as a single argument: .. code-block:: python from pyramid.paster import bootstrap env = bootstrap('/path/to/my/development.ini') print env['request'].route_url('home') :func:`pyramid.paster.bootstrap` returns a dictionary containing framework-related information. This dictionary will always contain a :term:`request` object as its ``request`` key. The following keys are available in the ``env`` dictionary returned by :func:`pyramid.paster.bootstrap`: request A :class:`pyramid.request.Request` object implying the current request state for your script. app The :term:`WSGI` application object generated by bootstrapping. root The :term:`resource` root of your :app:`Pyramid` application. This is an object generated by the :term:`root factory` configured in your application. registry The :term:`application registry` of your :app:`Pyramid` application. closer A parameterless callable that can be used to pop an internal :app:`Pyramid` threadlocal stack (used by :func:`pyramid.threadlocal.get_current_registry` and :func:`pyramid.threadlocal.get_current_request`) when your scripting job is finished. Let's assume that the ``/path/to/my/development.ini`` file used in the example above looks like so: .. code-block:: ini [pipeline:main] pipeline = translogger another [filter:translogger] filter_app_factory = egg:Paste#translogger setup_console_handler = False logger_name = wsgi [app:another] use = egg:MyProject The configuration loaded by the above bootstrap example will use the configuration implied by the ``[pipeline:main]`` section of your configuration file by default. Specifying ``/path/to/my/development.ini`` is logically equivalent to specifying ``/path/to/my/development.ini#main``. In this case, we'll be using a configuration that includes an ``app`` object which is wrapped in the Paste "translogger" middleware (which logs requests to the console). You can also specify a particular *section* of the PasteDeploy ``.ini`` file to load instead of ``main``: .. code-block:: python from pyramid.paster import bootstrap env = bootstrap('/path/to/my/development.ini#another') print env['request'].route_url('home') The above example specifies the ``another`` ``app``, ``pipeline``, or ``composite`` section of your PasteDeploy configuration file. The ``app`` object present in the ``env`` dictionary returned by :func:`pyramid.paster.bootstrap` will be a :app:`Pyramid` :term:`router`. Changing the Request ~~~~~~~~~~~~~~~~~~~~ By default, Pyramid will generate a request object in the ``env`` dictionary for the URL ``http://localhost:80/``. This means that any URLs generated by Pyramid during the execution of your script will be anchored here. This is generally not what you want. So how do we make Pyramid generate the correct URLs? Assuming that you have a route configured in your application like so: .. code-block:: python config.add_route('verify', '/verify/{code}') You need to inform the Pyramid environment that the WSGI application is handling requests from a certain base. For example, we want to mount our application at `example.com/prefix` and the generated URLs should use HTTPS. This can be done by mutating the request object: .. code-block:: python from pyramid.paster import bootstrap env = bootstrap('/path/to/my/development.ini#another') env['request'].host = 'example.com' env['request'].scheme = 'https' env['request'].script_name = '/prefix' print env['request'].application_url # will print 'https://example.com/prefix/another/url' Now you can readily use Pyramid's APIs for generating URLs: .. code-block:: python env['request'].route_url('verify', code='1337') # will return 'https://example.com/prefix/verify/1337' Cleanup ~~~~~~~ When your scripting logic finishes, it's good manners (but not required) to call the ``closer`` callback: .. code-block:: python from pyramid.paster import bootstrap env = bootstrap('/path/to/my/development.ini') # .. do stuff ... env['closer']() Setting Up Logging ~~~~~~~~~~~~~~~~~~ By default, :func:`pyramid.paster.bootstrap` does not configure logging parameters present in the configuration file. If you'd like to configure logging based on ``[logger]`` and related sections in the configuration file, use the following command: .. code-block:: python import logging.config logging.config.fileConfig('/path/to/my/development.ini')