Creating a repoze.bfg Project

You can use the repoze.bfg sample application generator to get started. This generator uses Paste templates to aid in the creation of a new project.

Creating the Project

To start a repoze.bfg project, use the paster create facility using the interpreter from the virtualenv (bfgenv) directory you created in Installing repoze.bfg.

$ bin/paster create -t bfg_starter

paster create will ask you a single question: the name of the project. You should use a string without spaces and with only letters in it. Here’s sample output from a run of paster create for a project we name MyProject:

$ bin/paster create -t bfg_starter
Selected and implied templates:
  repoze.bfg#bfg  repoze.bfg starter project

Enter project name: MyProject
Variables:
  egg:      MyProject
  package:  myproject
  project:  MyProject
Creating template bfg
Creating directory ./MyProject
  Recursing into +package+
    Creating ./MyProject/myproject/
    Copying __init__.py to ./MyProject/myproject/__init__.py
    Copying configure.zcml to ./MyProject/myproject/configure.zcml
    Copying models.py to ./MyProject/myproject/models.py
    Copying run.py_tmpl to ./MyProject/myproject/run.py
    Recursing into templates
      Creating ./MyProject/myproject/templates/
      Copying mytemplate.pt to ./MyProject/myproject/templates/mytemplate.pt
      Recursing into static
        Creating ./MyProject/myproject/templates/static/
        Copying default.css to ./MyProject/myproject/templates/static/default.css
        Recursing into images
          Creating ./MyProject/myproject/templates/static/images/
          Copying img01.gif to ./MyProject/myproject/templates/static/images/img01.gif
          Copying img02.gif to ./MyProject/myproject/templates/static/images/img02.gif
          Copying img03.gif to ./MyProject/myproject/templates/static/images/img03.gif
          Copying img04.gif to ./MyProject/myproject/templates/static/images/img04.gif
          Copying spacer.gif to ./MyProject/myproject/templates/static/images/spacer.gif
        Copying templatelicense.txt to ./MyProject/myproject/templates/static/templatelicense.txt
    Copying tests.py_tmpl to ./MyProject/myproject/tests.py
    Copying views.py_tmpl to ./MyProject/myproject/views.py
  Copying +project+.ini_tmpl to ./MyProject/MyProject.ini
  Copying CHANGES.txt_tmpl to ./MyProject/CHANGES.txt
  Copying README.txt_tmpl to ./MyProject/README.txt
  Copying ez_setup.py to ./MyProject/ez_setup.py
  Copying setup.py_tmpl to ./MyProject/setup.py
Running /Users/chrism/projects/repoze/bfg/bin/python setup.py egg_info

As a result of invoking paster create, a project is created in a directory named MyProject. That directory is a setuptools project directory from which a Python setuptools distribution can be created. The setup.py file in that directory can be used to distribute your application, or install your application for deployment or development. A sample PasteDeploy .ini file named MyProject.ini will also be created in the project directory. You will use the paster serve command against this .ini file to run your application.

The MyProject project directory contains an additional subdirectory named myproject (note the case difference) representing a Python package which holds very simple repoze.bfg sample code. This is where you’ll edit your application’s Python code and templates.

Note

You can skip the interrogative question about a project name during paster create by adding the project name to the command line, e.g. paster create -t bfg_starter MyProject.

Note

Convenience Paste templates for projects which will depend on ZODB or SQLAlchemy also exist. Use paster create -t bfg_zodb to create a project that depends on ZODB. Use paster create -t bfg_routesalchemy to create a project that depends on SQLAlchemy and URL dispatch (no traversal). Use paster create -t bfg_alchemy to create a project that depends on SQLAlchemy but not URL dispatch (uses only traversal).

Installing your Newly Created Project for Development

Using the interpreter from the virtualenv you create during Installing repoze.bfg, invoke the following command when inside the project directory against the generated setup.py:

$ ../bin/python setup.py develop

Elided output from a run of this command is shown below:

$ ../bin/python setup.py develop
...
Finished processing dependencies for MyProject==0.1

This will install your application’s package into the interpreter so it can be found and run as a WSGI application inside a WSGI server.

Running The Tests For Your Application

To run unit tests for your application, you should invoke them like so:

$ ../bin/python setup.py test -q

Here’s sample output from a test run:

$ python setup.py test -q
running test
running egg_info
writing requirements to MyProject.egg-info/requires.txt
writing MyProject.egg-info/PKG-INFO
writing top-level names to MyProject.egg-info/top_level.txt
writing dependency_links to MyProject.egg-info/dependency_links.txt
writing entry points to MyProject.egg-info/entry_points.txt
reading manifest file 'MyProject.egg-info/SOURCES.txt'
writing manifest file 'MyProject.egg-info/SOURCES.txt'
running build_ext
..
----------------------------------------------------------------------
Ran 2 tests in 0.647s

OK

The tests are found in the tests.py module in your paster create -generated project. Two sample tests exist.

The Interactive Shell

Once you’ve installed your program for development using setup.py develop, you can use an interactive shell to examine your repoze.bfg application model objects from a Python prompt. To do so, use the paster shell command with the bfgshell argument:

The first argument to bfgshell is the path to your application’s .ini file. The second is the section name inside the .ini file which points to your application as opposed to any other section within the .ini file. For example, if your application .ini file might have a [app:main] section that looks like so:

If so, you can use the following command to invoke a debug shell using the name main as a section name:

 [chrism@vitaminf bfgshellenv]$ ../bin/paster bfgshell MyProject.ini main

 Python 2.4.5 (#1, Aug 29 2008, 12:27:37)
 [GCC 4.0.1 (Apple Inc. build 5465)] on darwin
 Type "help" for more information. "root" is the BFG app root object.
 >>> root
 <foo.models.MyModel object at 0x445270>

If that command fails because paster claims it knows nothing about the “bfgshell” command (this happens under certain conditions that are not yet well-understood) try passing the flag --plugin=repoze.bfg before the filename:

 [chrism@vitaminf bfgshellenv]$ ../bin/paster --plugin=repoze.bfg bfgshell MyProject.ini main

Press “Ctrl-D” to exit the interactive shell.

You should always use a section name argument that refers to the actual app section within the Paste configuration file that points at your BFG application without any middleware wrapping. In particular, a section name is inappropriate as the second argument to “bfgshell” if the configuration section it names is a pipeline rather than an app.

Runnning The Project Application

Once the project is installed for development, you can run the application it represents using the paster serve command against the generated MyProject.ini configuration file:

$ ../bin/paster serve MyProject.ini

Here’s sample output from a run:

$ paster serve MyProject.ini
Starting server in PID 16601.
serving on 0.0.0.0:6543 view at http://127.0.0.1:6543

By default, generated repoze.bfg applications will listen on port 6543.

Note

During development, it’s often useful to run paster serve using its --reload option. When any Python module your project uses, changes, it will restart the server, which makes development easier, as changes to Python code under repoze.bfg is not put into effect until the server restarts.

Viewing the Application

Visit http://localhost:6543/ in your browser. You will see something in your browser like what is displayed below:

That’s the page shown by default when you visit an unmodified paster create-generated application.

The Project Structure

Our generated repoze.bfg application is a setuptools project (named MyProject), which contains a Python package (which is also named myproject, but lowercased; the paster template generates a project which contains a package that shares its name except for case).

The MyProject project has the following directory structure:

MyProject/
|-- CHANGES.txt
|-- README.txt
|-- ez_setup.py
|-- myproject
|   |-- __init__.py
|   |-- configure.zcml
|   |-- models.py
|   |-- run.py
|   |-- templates
|   |   |-- mytemplate.pt
|   |   `-- static/
|   |-- tests.py
|   `-- views.py
|-- MyProject.ini
`-- setup.py

The MyProject Project

The MyProject project is the distribution and deployment wrapper for your application. It contains both the myproject package representing your application as well as files used to describe, run, and test your application.

1. CHANGES.txt describes the changes you’ve made to the application. It is conventionally written in ReStructuredText format.
2. README.txt describes the application in general. It is conventionally written in ReStructuredText format.
3. ez_setup.py is a file that is used by setup.py to install Setuptools if the executing user does not have it installed.
4. MyProject.ini is a PasteDeploy configuration file that can be used to execute your application.
5. setup.py is the file you’ll use to test and distribute your application. It is a standard setuptools setup.py file.

We won’t describe the CHANGES.txt or README.txt files. ez_setup.py is a file only used by setup.py in case a user who wants to install your package does not have Setuptools already installed. It is only imported by and used by setup.py, so we won’t describe it here either.

MyProject.ini

The MyProject.ini file is a PasteDeploy configuration file. Its purpose is to specify an application to run when you invoke paster serve when you start an application, as well as the options provided to that application.

The generated MyProject.ini file looks like so:

[DEFAULT]
debug = true

[app:main]
use = egg:MyProject#app
reload_templates = true
debug_authorization = false
debug_notfound = false

[server:main]
use = egg:Paste#http
host = 0.0.0.0
port = 6543

This file contains several “sections” including [DEFAULT], [app:main], and [server:main].

The [DEFAULT] section consists of global parameters that are shared by all the applications, servers and middleware defined within the configuration file. By default it contains one key debug, which is set to true. This key is used by various components to decide whether to act in a “debugging” mode. repoze.bfg itself does not do anything with this parameter as of this writing, and neither does the generated sample application.

The [app:main] section represents configuration for your application. This section name represents the main application (and it’s an app -lication, thus app:main), sigifiying that this is the default application run by paster serve when it is invoked against this configuration file. The name main is a convention signifying that it the default application.

The use setting is required in the [app:main] section. The use setting points at a setuptools entry point named MyProject#app (the egg: prefix in egg:MyProject#app indicates that this is an entry point URI specifier, where the “scheme” is “egg”; there are no other schemes currently, so the egg: prefix is arguably not very useful).

Note

This part of configuration can be confusing so let’s try to clear things up a bit. Take a look at the generated setup.py file for this project. Note that the entry_point line in setup.py points at a string which looks a lot like an .ini file. This string representation of an .ini file has a section named [paste.app_factory]. Within this section, there is a key named app (the entry point name) which has a value myproject.run:app. The key app is what our egg:MyProject#app value of the use section in our config file is pointing at. The value represents a Python “dotted-name” path, which refers to a callable in our myproject package’s run.py module.

In English, this entry point can thus be referred to as a “Paste application factory in the MyProject project which has the entry point named app where the entry point refers to a app function in the mypackage.run module”. If indeed if you open up the run.py module generated within the myproject package, you’ll see a app function. This is the function called PasteDeploy when the paster serve command is invoked against our application. It accepts a global configuration object and returns an instance of our application.

The use setting is the only setting required in the [app:main] section unless you’ve changed the callable referred to by the MyProject#app entry point to accept more arguments: other settings you add to this section are passed as keywords arguments to the callable represented by this entry point (app in our run.py module). You can provide startup-time configuration parameters to your application by requiring more settings in this section.

The reload_templates setting in the [app:main] section is a repoze.bfg-specific setting which is passed into the framework. If it exists, and is true, Chameleon template changes will not require an application restart to be detected. See Automatically Reloading Templates for more information.

Warning

The reload_templates option should be turned off for production applications, as template rendering is slowed when it is turned on.

Various other settings may exist in this section having to do with debugging or influencing runtime behavior of a repoze.bfg application. See Environment and Configuration for more information about these settings.

The [server:main] section of the configuration file configures a WSGI server which listens on port 6543. It is configured to listen on all interfaces (0.0.0.0). The Paste#http server will create a new thread for each request.

Note

In general, repoze.bfg applications should be threading-aware. It is not required that a repoze.bfg application be nonblocking as all application code will run in its own thread, provided by the server you’re using.

See the PasteDeploy documentation for more information about other types of things you can put into this .ini file, such as other applications, middleware and alternate servers.

setup.py

The setup.py file is a setuptools setup file. It is meant to be run directly from the command line to perform a variety of functions, such as testing your application, packaging, and distributing your application.

Note

setup.py is the defacto standard which Python developers use to distribute their reusable code. You can read more about setup.py files and their usage in the Setuptools documentation.

Our generated setup.py looks like this:

import os

from ez_setup import use_setuptools
use_setuptools()

from setuptools import setup, find_packages

here = os.path.abspath(os.path.dirname(__file__))
README = open(os.path.join(here, 'README.txt')).read()
CHANGES = open(os.path.join(here, 'CHANGES.txt')).read()

setup(name='MyProject',
      version='0.1',
      description='MyProject',
      long_description=README + '\n\n' +  CHANGES,
      classifiers=[
        "Development Status :: 3 - Alpha",
        "Intended Audience :: Developers",
        "Programming Language :: Python",
        "Topic :: Internet :: WWW/HTTP",
        "Topic :: Internet :: WWW/HTTP :: Dynamic Content",
        "Topic :: Internet :: WWW/HTTP :: WSGI",
        "Topic :: Internet :: WWW/HTTP :: WSGI :: Application",
        ],
      author='',
      author_email='',
      url='',
      keywords='web wsgi bfg zope',
      packages=find_packages(),
      include_package_data=True,
      zip_safe=False,
      install_requires=[
            'repoze.bfg',
            ],
      tests_require=[
            'repoze.bfg',
            ],
      test_suite="myproject",
      entry_points = """\
      [paste.app_factory]
      app = myproject.run:app
      """
      )

The top of the file imports and uses ez_setup, which causes Setuptools to be installed on an invoking user’s computer if it isn’t already. The setup.py file calls the setuptools setup function, which does various things depending on the arguments passed to setup.py on the command line.

Within the arguments to this function call, information about your application is kept. While it’s beyond the scope of this documentation to explan everything about setuptools setup files, we’ll provide a whirlwind tour of what exists in this file here.

Your application’s name (this can be any string) is specified in the name field. The version number is specified in the version value. A short description is provided in the description field. The long_description is conventionally the content of the README and CHANGES file appended together. The classifiers field is a list of Trove classifiers describing your application. author and author_email are text fields which probably don’t need any description. url is a field that should point at your application project’s URL (if any). packages=find_packages() causes all packages within the project to be found when packaging the application. include_package_data will include non-Python files when the application is packaged if those files are checked into version control. zip_safe indicates that this package is not safe to ship as a zipped egg (it will unpack as a directory, which is more convenient). install_requires and tests_require indicate that this package depends on the repoze.bfg package. test_suite points at the package for our application, which means all tests found in the package will be installed. We examined entry_points in our discussion of the MyProject.ini file; this file defines the app entry point that represent’s our project’s application.

Usually you only need to think about the contents of the setup.py file when distributing your application to other people, or when versioning your application for your own use. For fun, you can try this command now:

python setup.py sdist

This will create a tarball of your application in a dist subdirectory named MyProject-0.1.tar.gz. You can send this tarball to other people who want to use your application.

Warning

By default, setup.py sdist does not place non-Python-source files in generated tarballs. This means, in this case, that the templates/mytemplate.pt file and the files in the templates/static directory are not packaged in the tarball. To allow this to happen, check all the files that you’d like to be distributed along with your application’s Python files into a version control system such as Subversion. After you do this, when you rerun setup.py sdist, all files checked into the version control system will be included in the tarball.

The myproject Package

The myproject package lives inside the MyProject project. It contains:

1. An __init__.py file which signifies that this is a Python package. It is conventionally empty, save for a single comment at the top.
2. A configure.zcml is a ZCML file which maps view names to model types. This is also known as the application registry.
3. A models.py module, which contains model code.
4. A run.py module, which contains code that helps users run the application.
5. A templates directory, which contains Chameleon (or other types of) templates.
6. A tests.py module, which contains unit test code for the application.
7. A views.py module, which contains view code for the application.

These are purely conventions established by the paster template: repoze.bfg doesn’t insist that you name things in any particular way.

configure.zcml

The configure.zcml represents the application registry. It looks like so:

<configure xmlns="http://namespaces.repoze.org/bfg">

  <!-- this must be included for the view declarations to work -->
  <include package="repoze.bfg.includes" />

  <view
     for=".models.MyModel"
     view=".views.my_view"
     />

  <view
     for=".models.MyModel"
     view=".views.static_view"
     name="static"
     />

</configure>

1. Lines 1 provides the root node and namespaces for the configuration language. http://namespaces.repoze.org/bfg is the default XML namespace. Add-on packages may require other namespaces.
2. Lines 4 initializes repoze.bfg-specific configuration directives by including the repoze.bfg.includes package. This causes all of the ZCML within the configure.zcml of the repoze.bfg.includes package (which can be found in the main repoze.bfg sources).
3. Lines 6-9 register a “default view” (a view that has no name attribute). It is for model objects that are instances of the MyModel class. The view attribute points at a Python function that does all the work for this view. Note that the values of both the for attribute and the view attribute begin with a single period. Names that begin with a period are “shortcuts” which point at files relative to the package in which the configure.zcml file lives. In this case, since the configure.zcml file lives within the myproject package, the shorcut .models.MyModel could also be spelled myproject.models.MyModel (forming a full Python dotted-path name to the MyModel class). Likewise the shortcut .views.my_view could be replaced with myproject.views.my_view.
4. Lines 11-15 register a view named static. This view declaration points at the static_view, which is a view implementation that serves static files from the filesystem for the default application.

views.py

Much of the heavy lifting in a repoze.bfg application comes in the form of views. A view is the bridge between the content in the model, and the response given back to a browser.

from repoze.bfg.chameleon_zpt import render_template_to_response
from repoze.bfg.view import static

static_view = static('templates/static')

def my_view(context, request):
    return render_template_to_response('templates/mytemplate.pt',
                                       request = request,
                                       project = 'MyProject')

1. Lines 1-2 import required functions.

2. Line 4 sets up a static_view which will be consulted when visitors visit /static/<something>. This view will serve up CSS and images in our default application. This view is registered in configure.zcml as the static view name for the class MyModel (the root).

3. Lines 6-9 provide the my_view that was registered as the view. configure.zcml said that the default URL for instances that are of the class MyModel should run this my_view function.

   The function is handed two pieces of information: the context and the request. The context is the term model found via traversal (or via URL dispatch). The request is an instance of the WebOb Request class representing the browser’s request to our server.

4. The view renders a Chameleon template and returns the result as the response. Note that because our MyProject.ini has a reload_templates = true directive indicating that templates should be reloaded when they change, you won’t need to restart the application server to see changes you make to templates. During development, this is handy. If this directive had been false (or if the directive did not exist), you would need to restart the application server for each template change. For production applications, you should set your project’s reload_templates to false to increase the speed at which templates may be rendered.

Note

This example uses render_template_to_response which is a shortcut function. If you want more control over the response, use the render_template function, also present in repoze.bfg.chameleon_zpt. You may then create your own WebOb Response object, using the result of render_template as the response’s body. There is also a get_template API in the same module, which you can use to retrieve the template object without rendering it at all, for additional control.

Note

For more information about the static view helper function see Serving Static Resources Using a View.

models.py

The models.py module provides the model data for our application. We write a class named MyModel that provides the behavior.

class MyModel(object):
    pass

root = MyModel()

def get_root(environ):
    return root

1. Lines 1-2 define the MyModel class.
2. Line 4 defines an instance of MyModel as the root.
3. Line 6 is a “root factory” function that will be called by the repoze.bfg Router for each request when it wants to find the root of the model graph. Conventionally this is called get_root.

In a “real” application, the root object would not be such a simple object. Instead, it would be an object that could access some persistent data store, such as a database. repoze.bfg doesn’t make any assumption about which sort of datastore you’ll want to use, so the sample application uses an instance of MyModel to represent the root.

run.py

We need a small Python module that configures our application and advertises itself to our PasteDeploy .ini file. For convenience, we also make it possible to run this module directory without the PasteDeploy configuration file:

from repoze.bfg.router import make_app

def app(global_config, **kw):
    """ This function returns a repoze.bfg.router.Router object.  It
    is usually called by the PasteDeploy framework during ``paster
    serve``"""
    # paster app config callback
    from myproject.models import get_root
    import myproject
    return make_app(get_root, myproject, options=kw)

1. Line 1 imports the make_app functions from repoze.bfg.router that we use later.
2. Lines 3-10 define a function that returns a repoze.bfg Router application from repoze.bfg.router . This is meant to be called by the PasteDeploy framework as a result of running paster serve.

templates/mytemplate.pt

The single Chameleon template in the project looks like so:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:tal="http://xml.zope.org/namespaces/tal">
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title>${project} Application</title>
<meta name="keywords" content="python web application" />
<meta name="description" content="repoze.bfg web application" />
<link href="${request.application_url}/static/default.css" rel="stylesheet" type="text/css" />
</head>
<body>
<!-- start header -->
<div id="logo">
  <h2><code>${project}</code>, a <code>repoze.bfg</code> application</h2>
</div>
<div id="header">
  <div id="menu">
  </div>
</div>
<!-- end header -->
<div id="wrapper">
  <!-- start page -->
  <div id="page">
    <!-- start content -->
    <div id="content">
      <div class="post">
	<h1 class="title">Welcome to <code>${project}</code>, an
	application generated by the <a
	href="http://static.repoze.org/bfgdocs">repoze.bfg</a> web
	application framework.</h1>
      </div>
    </div>
    <!-- end content -->
    <!-- start sidebar -->
    <div id="sidebar">
      <ul>
	<li id="search">
	  <h2>Search<br/> <code>repoze.bfg</code> Documentation</h2>
	  <form method="get" 
                action="http://static.repoze.org/bfgdocs/search.html">
	    <fieldset>
	      <input type="text" id="q" name="q" value="" />
	      <input type="submit" id="x" value="Search" />
	    </fieldset>
	  </form>
	</li>
	<li>
	  <h2><code>repoze.bfg</code> links</h2>
	  <ul>
	    <li><a
	    href="http://static.repoze.org/bfgdocs/#narrative-documentation">Narrative
	    Documentation</a>
            </li>
	    <li>
              <a
              href="http://static.repoze.org/bfgdocs/#api-documentation">API
              Documentation</a>
            </li>
	    <li>
              <a
              href="http://static.repoze.org/bfgdocs/#tutorials">Tutorials</a>
            </li>
	    <li>
              <a
              href="http://static.repoze.org/bfgdocs/#change-history">Change
              History</a>
            </li>
	    <li>
              <a
              href="http://static.repoze.org/bfgdocs/#sample-applications">Sample
              Applications</a>
            </li>
	    <li>
              <a
              href="http://static.repoze.org/bfgdocs/#support-and-development">Support
              and Development</a>
            </li>
	    <li>
              <a
              href="irc://irc.freenode.net#repoze">IRC Channel</a>
            </li>
	  </ul>
	</li>
      </ul>
    </div>
    <!-- end sidebar -->
    <div style="clear: both;">&nbsp;</div>
  </div>
</div>
<!-- end page -->
<!-- start footer -->
<div id="footer">
  <p id="legal">( c ) 2008. All Rights Reserved. Template design
  by <a href="http://www.freecsstemplates.org/">Free CSS
  Templates</a>.</p>
</div>
<!-- end footer -->
</body>
</html>

It displays a default page when rendered. It is referenced by the my_view function in the views.py module. Templates are accessed and used by view functions.

templates/static

This directory contains static resources which support the mytemplate.pt template. It includes CSS and images.

tests.py

The tests.py module includes unit tests for your application.

import unittest

from repoze.bfg import testing

class ViewTests(unittest.TestCase):

    """ These tests are unit tests for the view.  They test the
    functionality of *only* the view.  They register and use dummy
    implementations of repoze.bfg functionality to allow you to avoid
    testing 'too much'"""

    def setUp(self):
        """ cleanUp() is required to clear out the application registry
        between tests (done in setUp for good measure too)
        """
        testing.cleanUp()
        
    def tearDown(self):
        """ cleanUp() is required to clear out the application registry
        between tests
        """
        testing.cleanUp()

    def test_my_view(self):
        from myproject.views import my_view
        context = testing.DummyModel()
        request = testing.DummyRequest()
        renderer = testing.registerDummyRenderer('templates/mytemplate.pt')
        response = my_view(context, request)
        renderer.assert_(project='MyProject')

class ViewIntegrationTests(unittest.TestCase):
    """ These tests are integration tests for the view.  These test
    the functionality the view *and* its integration with the rest of
    the repoze.bfg framework.  They cause the entire environment to be
    set up and torn down as if your application was running 'for
    real'.  This is a heavy-hammer way of making sure that your tests
    have enough context to run properly, and it tests your view's
    integration with the rest of BFG.  You should not use this style
    of test to perform 'true' unit testing as tests will run faster
    and will be easier to write if you use the testing facilities
    provided by bfg and only the registrations you need, as in the
    above ViewTests.
    """
    def setUp(self):
        """ This sets up the application registry with the
        registrations your application declares in its configure.zcml
        (including dependent registrations for repoze.bfg itself).
        """
        testing.cleanUp()
        import myproject
        import zope.configuration.xmlconfig
        zope.configuration.xmlconfig.file('configure.zcml',
                                          package=myproject)

    def tearDown(self):
        """ Clear out the application registry """
        testing.cleanUp()

    def test_my_view(self):
        from myproject.views import my_view
        context = testing.DummyModel()
        request = testing.DummyRequest()
        result = my_view(context, request)
        self.assertEqual(result.status, '200 OK')
        body = result.app_iter[0]
        self.failUnless('Welcome to' in body)
        self.assertEqual(len(result.headerlist), 2)
        self.assertEqual(result.headerlist[0],
                         ('content-type', 'text/html; charset=UTF-8'))
        self.assertEqual(result.headerlist[1], ('Content-Length',
                                                str(len(body))))

This sample tests.py file has a single unit test and a single integration test defined within it. These two tests are executed when you run python setup.py test -q. You may add more tests here as you build your application. You are not required to write tests to use repoze.bfg, this file is simply provided as convenience and example.