Skip to main content
Join the official 2020 Python Developers SurveyStart the survey!

Easily hook into the ZCML processing machinery

Project description


This package provides means of hooking into the Zope (ZCML) configuration process.

Custom ZCML actions

It is sometimes useful to execute a function during the execution of configuration actions, for example to perform one-off configuration that does not warrant a new directive. The <zcml:customAction /> directive is provided for this purpose.

For example, you may want to call a function called my.package.finalConfiguration() “late” in the configuration action execution cycle. This can be achieved with the following ZCML statements:


    <include package="z3c.zcmlhook" file="meta.zcml" />



The handler attribute gives the name of a function to execute. The function should take no arguments. The order attribute is optional, and can be used to influence when in the configuration cycle the function is executed. The default value for this, as for most Zope configuration actions, is 0.

Overriding custom actions

If you want to override the invocation of a custom handler in an overrides.zcml, you need to tell zope.configuration which handler to override. You can do that by setting the discriminator explicitly. A discriminator is used to uniquely identify a configuration action. In the case of the <zcml:customAction /> directive, the discriminator is based on the full dotted name to the function by default. Thus, you could override the function call above like so:


Using a handler more than once

The discriminator attribute can also be used to explicitly allow using the same handler more than once. If you wanted to call my.package.finalConfiguration again, you would normally get a configuration conflict. However, with a (unique) custom discriminator, the second call is allowed:



Here, we are attempting to call our configuration action “very early” as well as “very late” in the configuration process.


1.0b1 - January 2nd, 2010

  • Initial release [optilude]

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for z3c.zcmlhook, version 1.0b1
Filename, size File type Python version Upload date Hashes
Filename, size z3c.zcmlhook-1.0b1.tar.gz (5.5 kB) File type Source Python version None Upload date Hashes View

Supported by

Pingdom Pingdom Monitoring Google Google Object Storage and Download Analytics Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page