Resource Attributes Influencing Adding

Individual Starlark values representing resources expose various attributes prefixed with add_ which influence what happens when that resource is added to a resource collector. These attributes are derived from the PythonPackagingPolicy attached to the entity creating the resource. But they can be modified by Starlark code before the resource is added to a collection.

The following sections describe each attribute that influences how the resource is added to a collection.


This bool attribute defines a yes/no filter for whether to actually add this resource to a collection. If a resource with .add_include = False is added to a collection, that add is processed as a no-op and no change is made.


This string attributes defines the primary location this resource should be added to and loaded from at run-time.

It can be set to the following values:


The resource should be loaded from memory.

For Python modules and resource files, the module is loaded from memory using 0-copy by the custom module importer.

For Python extension modules, the extension module may be statically linked into the built binary or loaded as a shared library from memory (the latter is not supported on all platforms).


The resource is materialized on the filesystem relative to the built entity and loaded from the filesystem at run-time.

<prefix> here is a directory prefix to place the resource in. . (e.g. filesystem-relative:.) can be used to denote the same directory as the built entity.


This string or None value attribute is equivalent to add_location except it only comes into play if the location specified by add_location could not be satisfied.

Some resources (namely Python extension modules) cannot exist in all locations. Setting this attribute to a different location gives more flexibility for packaging resources with location constraints.


This bool attribute defines whether to add source code for a Python module.

For Python modules, typically only bytecode is required at run-time. For some applications, the presence of source code doesn’t provide sufficient value or isn’t desired since the application developer may want to obfuscate the source code. Setting this attribute to False prevents Python module source code from being added.


This bool attributes defines whether to add Python bytecode for optimization level 0 (the default optimization level).

If True, Python source code will be compiled to bytecode at build time.

The default value is whatever PythonPackagingPolicy.bytecode_optimize_level_zero is set to.


This bool attributes defines whether to add Python bytecode for optimization level 1.

The default value is whatever PythonPackagingPolicy.bytecode_optimize_level_one is set to.


This bool attributes defines whether to add Python bytecode for optimization level 2.

The default value is whatever PythonPackagingPolicy.bytecode_optimize_level_two is set to.