nab-provider

Apply Python packaging rules during dependency resolution. This package supplies candidate versions and their dependency constraints to nab-resolver, including environment markers and build, distribution, and VCS policies.

It performs no networking, file access, or subprocess calls.

Package listings and metadata arrive through nab_provider.fetch_port.FetchPort, an interface implemented by the application using the provider. That application is called the host; nab-project supplies it for the nab CLI. nab_provider.testing supplies an in-memory implementation for tests.

When to use it

Use nab-provider to embed nab's resolution in a host that already owns its networking and caching, keeping nab-index out of the import graph. Most users want nab instead.

The API is currently under rapid experimentation, if you use it pin to an exact version.