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Python 2 is no longer supported by the community. We recommend that you migrate Python 2 apps to Python 3.

DescriptorLibrary Functions

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.