`GLOBAL_TOOLKIT_REGISTRY`

openff.toolkit.utils.toolkits.GLOBAL_TOOLKIT_REGISTRY = <ToolkitRegistry containing The RDKit, AmberTools, Built-in Toolkit>

The toolkit registry used by default when no registry or wrapper is specified.

A toolkit registry is a list of toolkit wrappers used to provide functionality not implemented by the OpenFF Toolkit itself. Any given functionality is requested from each toolkit in order until one is found that provides it. For more information, see ToolkitRegistry.

To temporarily modify the GLOBAL_TOOLKIT_REGISTRY, see toolkit_registry_manager().

Examples

Check the default toolkit precedence order:

>>> from openff.toolkit import GLOBAL_TOOLKIT_REGISTRY
>>> GLOBAL_TOOLKIT_REGISTRY.registered_toolkits() 
[...]

Temporarily change the global toolkit registry:

>>> from openff.toolkit import ToolkitRegistry, RDKitToolkitWrapper
>>> from openff.toolkit.utils import toolkit_registry_manager
>>> with toolkit_registry_manager(ToolkitRegistry([RDKitToolkitWrapper]))):
>>>     GLOBAL_TOOLKIT_REGISTRY
<ToolkitRegistry containing The RDKit>
>>>     mol = Molecule.from_smiles("CCO")
>>> # when the context manager ends, the default registry is back to normal
>>> GLOBAL_TOOLKIT_REGISTRY
<ToolkitRegistry containing The RDKit, AmberTools, Built-in Toolkit>

To change the value of GLOBAL_TOOLKIT_REGISTRY for the remainder of the Python process, individual toolkits can be added or removed with the ToolkitRegistry.deregister_toolkit() and ToolkitRegistry.register_toolkit() methods. This can be useful for debugging and exploring subtly different behavior between toolkit wrappers:

>>> print(len(GLOBAL_TOOLKIT_REGISTRY.registered_toolkits))
4
>>> GLOBAL_TOOLKIT_REGISTRY.deregister_toolkit(RDKitToolkitWrapper)
>>> print(len(GLOBAL_TOOLKIT_REGISTRY.registered_toolkits))
3
>>> GLOBAL_TOOLKIT_REGISTRY.register_toolkit(RDKitToolkitWrapper)
>>> print(len(GLOBAL_TOOLKIT_REGISTRY.registered_toolkits))
4

Note that as with other global attributes in Python, assigning a new toolkit registry to GLOBAL_TOOLKIT_REGISTRY is quite difficult to get right and very likely to fail silently - we recommend modifying the existing value instead in most cases.