How-to: Writing setup handlers for Products.GenericSetup
¶
If your product subclasses existing tools or provides new tools (or new sub-object classes), it might need to supply its own setup handlers in order to support exporting / importing tool settings using GenericSetup.
Step 1:¶
Identify those classes in your product that need their own setup handlers. In theory you don’t need your own handlers for classes which implement a CMF tool interface that already has a setup adapter. In practice the adapters shipped with the CMF sometimes use methods that are not part of the interface, so you have to verify that they really work for your classes.
Step 2:¶
Make sure those classes that need setup handlers have Zope3 style interfaces. Later you will write setup adapters for those interfaces.
Step 3:¶
Create an exportimport
module inside your product. If you plan to write
many setup handlers this can be a sub-package.
Step 4:¶
Decide which kind of setup handler you need:
- body adapter
- For objects represented by a complete file body. Provides
Products.GenericSetup.interfaces.IBody
. - XML adapter
- A ‘body adapter’ in XML format. Also provides
Products.GenericSetup.interfaces.IBody
, but has its own base class because XML is the preferred format. - node adapter
- For sub-objects represented by an XML node of the parent’s XML document.
Provides
Products.GenericSetup.interfaces.INode
. This is useful for sub-objects of complex tools. Custom catalog index or action classes need this kind of adapter. - import and export steps
- Top level handlers can be registered to manage import steps and / or export steps and call the body adapters.
If you use the base classes from Products.GenericSetup.utils
, XML and
node adapters are implemented in a very similar way. Both can mix in
ObjectManagerHelpers
and PropertyManagerHelpers
.
Step 5:¶
Products.CMFCore.exportimport
contains many examples for XML and
node adapters. If you need a pure body adapter,
Products.GenericSetup.PythonScripts
would be a good
example. Follow those examples and write your own multi adapter, register
it for the interface of your class and for
Products.GenericSetup.interfaces.ISetupEnviron
and don’t forget
to write unit tests.
Adapters follow the convention that self.context
is always the primary
adapted object, so the minimal setup context (ISetupEnviron
) used in these
multi adapters is self.environ
.
XML and body adapters are always also small node adapters. This way the
XML file of the container contains the information that is necessary to
create an empty object. The handler of the container has to set up
sub-objects before we can adapt them and configure them with their own
handlers. The base classes in Products.GenericSetup.utils
will care about that.
Step 6:¶
If your adapter is a top-level adapter (e.g for a tool), you need import
and export steps that know how to use the adapter. Again there are many
examples in Products.CMFCore.exportimport
.
To make those steps available you have to add them to export_steps.xml
and import_steps.xml
of a setup profile and to load that profile into the
setup tool.
Step 7:¶
Now you are done. To ship default settings with your product, make your
settings through the ZMI (or set your stuff up the old way if you have old
setup code like an Install.py
) and export your settings using the setup
tool. Unpack the exported tarball into a profiles
subdirectory of your
product, and then add gs:registerProfile
entries to its configure.zcml
file to register that directory as a base profile or
extension profile.
See also
See About Profiles for more details.