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Python · architecture

pydantic-at-boundaries

python:pydantic-at-boundaries

Public function or route returns a fixed-shape untyped dictionary.

Code
SARJ008
Default
error
Fix
none
Languages
python

Why

Named boundary models make field types and required keys explicit to callers and tooling.

Fix

Return a pydantic model, frozen dataclass, or `TypedDict` for the fixed record shape.

Before / after

Executed by this rule’s unit tests.

Before

Untyped dictionary returned from a public function

service.py · focus
from typing import Any

def build_payload(call) -> dict[str, Any]:
    return {'id': call.id}

After

Named model returned from a public function

service.py · focus
def build_payload(call) -> CallPayload:
    return CallPayload(id=call.id)

Limits

  • Private functions, closures, tests, fixtures, validators, and dictionary conversion methods are excluded.
  • Only returned record literals and locally built fixed-shape dictionaries are recognized.