B2 SDK docs: inventory and classify the public names exported by b2sdk.v3 #597

Description

b2sdk.v3 re-exports a large surface from _internal, including high-level APIs, low-level HTTP classes, test simulators, constants, and implementation-oriented helpers. A static inventory at f3ab7b71 found 208 non-underscored names in the v3 root; 137 were not mentioned anywhere in the Sphinx .rst sources. This count is not evidence that all 137 names should be public. It demonstrates that the repository does not currently make the boundary explicit enough to tell intentional public exports from convenient or accidental re-exports.

Steps to reproduce

import b2sdk.v3

exported = sorted(name for name in vars(b2sdk.v3) if not name.startswith('_'))
print(exported)

Compare the result with the public API pages under doc/source/api, then sample low-level names such as B2Session, B2Http, RawSimulator, BucketFactory, and transfer-manager classes to determine whether their compatibility status is documented.

Expected behavior

Produce a reviewed inventory that classifies each root export as public, advanced public, testing support, deprecated compatibility, or internal implementation. Every intentionally public symbol should be discoverable from the API reference. Anything intentionally excluded should be covered by a clear interface-policy statement so users and maintainers understand whether compatibility is promised.

Actual behavior

The versioned root exposes substantially more names than the public API reference explains. This ambiguity affects users choosing imports and maintainers deciding whether a rename or removal requires a compatibility adapter and version-specific tests.

Environment

• Python version: Any supported version
• b2sdk version: master at f3ab7b71
• OS: Any