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Google App Engine

DescriptorLibrary Functions

Experimental!

ProtoRPC is an experimental, innovative, and rapidly changing new feature for App Engine. Unfortunately, being on the bleeding edge means that we may make backwards-incompatible changes to ProtoRPC. We will inform the community when this feature is no longer experimental.

A descriptor library is an object that contains known definitions. It contains a cache of descriptor objects mapped by definition name, and contains all types of descriptors except for file sets.

If the application provides a definition name that is not in the library, the application can include a descriptor loader that attempts to resolve the missing descriptor.

DescriptorLibrary is provided by the protorpc.descriptor module.

Functions

DescriptorLibrary provides the following functions:

lookup_descriptor(definition_name)

Gets a descriptor from the library for the given definition name. If the descriptor is not found, attempts to find it using the descriptor loader.

Arguments:

definition_name
The definition name for which to find a descriptor.

Returns a descriptor describing the definition name.

Raises a DefinitionNotFoundError error if no descriptor exists for the given definition name.

lookup_package(definition_name)

Determines the package name that any definition name belongs to. May check the parent for the package name. Attempts to resolve missing descriptors if provided a descriptor loader.

Arguments:

definition_name
The definition name for which to find a package.

Returns a descriptor object describing the package name.