Third-Party Integration in Python Packages

When creating a python package there are often instances where you want to integrate with other third-party packages. For example if you are creating an ORM package like sqlalchemy you may want integrations with different databases, but you may not want to take a direct dependency in your own package.

To check for the presence of the third-party package without taking it as a dependency the following decorator pattern can be used to perform the checks.

import functools
import importlib
 
def requires_package(func):
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        if importlib.util.find_spec("third-party-package") is None:
            raise ImportError("third-party-package must be installed to use this feature")
        return func(*args, **kwargs)
 
    return wrapper

Then from your individual methods or classes you can use this decorator and import the specific module you need.

@requires_package
def integration():
    from third_party_package import module
    result = module.do_work()