prerequisite.md

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html_meta description property=og:description property=og:title keywords Prerequisites for content types Prerequisites for content types Prerequisites for content types Plone, content types, prerequisites

Prerequisites

This portion of the Dexterity documentation mainly intends to illuminate Dexterity features. If you would like an in-depth, step-by-step approach, we recommend you work through the Mastering Plone training.

Prepare a development environment

First get a working Plone installation. If you don't already have one, the easiest way to do so is to use one of Plone's installers. Note that for development purposes, you may use a standalone (non-ZEO), non-root install.

Second add our standard development tools. If you've used one of our installers, developer tool configurations are in a separate file, develop.cfg. Once your site is running, you may activate the development configuration by using the command:

bin/buildout -c develop.cfg

Rather than running bin/buildout without arguments. The develop.cfg config file extends the existing buildout.cfg.

The key tools that you'll need, both supplied by develop.cfg, are:

1. mr.bob, a Python package skeleton builder;
2. bobtemplates.plone, mr.bob templates for Plone; and
3. A test runner and code quality testing tools.

If you've created yor own buildout.cfg file rather than using one of the installers, you'll need to add an equivalent development configuration. The easiest way to do so is to pick up a copy from the Unified Installer's repository. To pick up mr.bob and the Plone templates alone, just add a mrbob part to your buildout:

[mrbob]
recipe = zc.recipe.egg
eggs =
    mr.bob
    bobtemplates.plone

Don't forget to add mrbob to your parts list.

Creating a package

We're going to build a package named `example.conference`.
You may find a completed version of it in the [Collective repository](https://github.com/collective/example.conference).

Typically, our content types will live in a separate package from our theme and other customizations.

To create a new package, we can start with mrbob and the dexterity template.

Nothing that we're doing actually requires `mrbob` or the `bobtemplates.plone` skeleton package.
It's just a quick way of getting started.

We run the following from the src/ directory

../bin/mrbob bobtemplates.plone:addon -O example.conference

and specify your target version of Plone and Python. This will create a directory named example.conference inside ./src with the basic structure of a generic add-on. Now "refine" it for the creation of a content type.

../bin/mrbob bobtemplates.plone:content_type -O example.conference

Specify Program for your content type name, and Container as the Dexterity base class (remember that Programs will contain Sessions). Choose not to use XML Model for this example.

Now take a look at the setup.py file in your new package. Edit the author, author_email, and description fields as you wish. Note a couple of parts of the generated setup.py file:

install_requires=[

    'plone.app.dexterity',

],

entry_points="""
# -*- Entry points: -*-
[z3c.autoinclude.plugin]
target = plone
""",

The addition of plone.app.dexterity to our install requirements assures that we'll have Dexterity loaded, even in older versions of Plone. The specification of plone as a z3c.autoinclude.plugin entry point ensures that we won't need to separately specify our zcml in buildout.

Now let's take a look at configure.zcml in the examples/conference directory of our project. Again, we want to note a few parts:

<configure>

  <i18n:registerTranslations directory="locales" />

  <includeDependencies package="." />

  <include package=".browser" />

  <genericsetup:registerProfile
      name="default"
      title="collective.foo"
      directory="profiles/default"
      description="Installs the collective.foo add-on."
      provides="Products.GenericSetup.interfaces.EXTENSION"
      post_handler=".setuphandlers.post_install"
      />

  <genericsetup:registerProfile
      name="uninstall"
      title="collective.foo (uninstall)"
      directory="profiles/uninstall"
      description="Uninstalls the collective.foo add-on."
      provides="Products.GenericSetup.interfaces.EXTENSION"
      post_handler=".setuphandlers.uninstall"
      />

</configure>

Here, with the includeDependencies tag, we automatically include the ZCML configuration for all packages listed under install_requires in setup.py. The alternative would be to manually add a line, such as <include package="plone.app.dexterity" /> for each dependency.

The include package=".browser" directive loads additional ZCML configuration from the browser subdirectory. In turn, the browser.resourceDirectory command in that configuration file creates a directory for static resources that we want to make available through the web.

Finally, we register a GenericSetup profile to make the type installable, which we will build up over the next several sections.

When you've got your project tuned up, return to your buildout/instance directory and edit buildout.cfg to add example.conference to your eggs list, and src/example.conference to your develop sources list:

eggs =
    Plone

    example.conference


develop =

    src/example.conference

Run bin/buildout -c develop.cfg to add your new product to the configuration, or just bin/buildout if you don't have a separate develop.cfg.

The buildout should now configure Plone, Dexterity, and the example.conference package.

We are now ready to start adding types.