5.1.1 Python*Handler Directive Syntax

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5.1.1 Python*Handler Directive Syntax

All request handler directives have the following syntax:

`Python*Handler handler [handler ...] [ | .ext [.ext ...] ]`

Where handler is a callable object that accepts a single argument - request object, and .ext is a file extension.

Multiple handlers can be specified on a single line, in which case they will be called sequentially, from left to right. Same handler directives can be specified multiple times as well, with the same result - all handlers listed will be executed sequentially, from first to last.

If any handler in the sequence returns a value other than `apache.OK` or `apache.DECLINED`, then execution of all subsequent handlers for that phase are aborted. What happens when either `apache.OK` or `apache.DECLINED` is returned is dependent on which phase is executing.

Note that prior to mod_python 3.3, if any handler in the sequence, no matter which phase was executing, returned a value other than `apache.OK`, then execution of all subsequent handlers for that phase was aborted.

The list of handlers can optionally be followed by a `|` followed by one or more file extensions. This would restrict the execution of the handler to those file extensions only. This feature only works for handlers executed after the trans phase.

A handler has the following syntax:

`module[::object]`

Where module can be a full module name (package dot notation is accepted) or an actual path to a module code file. The module is loaded using the mod_python module importer as implemented by the `apache.import_module()` function. Reference should be made to the documentation of that function for further details of how module importing is managed.

The optional object is the name of an object inside the module. Object can also contain dots, in which case it will be resolved from left to right. During resolution, if mod_python encounters an object of type `<class>`, it will try instantiating it passing it a single argument, a request object.

If no object is specified, then it will default to the directive of the handler, all lower case, with the word "`python`"removed. E.g. the default object for PythonAuthenHandler would be authenhandler.

Example:

      PythonAuthzHandler mypackage.mymodule::checkallowed

For more information on handlers, see Overview of a Handler.

Side note: The "`::`" was chosen for performance reasons. In order for Python to use objects inside modules, the modules first need to be imported. Having the separator as simply a "`.`", would considerably complicate process of sequentially evaluating every word to determine whether it is a package, module, class etc. Using the (admittedly un-Python-like) "`::`" takes the time consuming work of figuring out where the module part ends and the object inside of it begins away from mod_python resulting in a modest performance gain.