mock-friendly-api-layering

Mock tests fail because internal routing parameters like url and timeout leak into public API wrappers and trigger unexpected kwargs in mock assertions. Refactoring public functions to drop transport parameters lets the internal helper own routing values, isolating transport concerns from business logic.

To prevent internal routing parameter leakage, refactor public functions to accept only business parameters while a shared internal _invoke-like helper owns routing values such as url or timeout. This keeps transport concerns at the lowest level and ensures mocks only see business parameters.

API layering in mock-heavy codebases separates public API wrappers from low-level transport helpers. It enforces a boundary where public functions handle business parameters and delegate routing values like url and timeout to an internal function, improving test reliability by isolating transport concerns.

API layering applies to HTTP, IPC, or any layered API wrappers where public APIs delegate to a transport function. The approach enforces that public functions accept only business parameters while the internal helper owns routing params, regardless of the underlying transport protocol.

You enforce the boundary by applying lint rules and tests that prevent public functions from accepting transport parameters. Refactoring public wrappers to drop routing values and letting the internal _invoke-like helper own them ensures mocks only encounter business parameters.