✨ Make ServerSentEvent generic with typed data field#16
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Introduce `ServerSentEvent[Data]` so endpoints that yield typed SSE events get a `contentSchema` in the OpenAPI spec reflecting the data payload type, while retaining full control over SSE fields (`event`, `id`, `retry`, `comment`). - `ServerSentEvent` now inherits from `Generic[Data]` with `data: Data` - `validate_default=True` ensures `ServerSentEvent[Item]()` raises a ValidationError (data is effectively required when Data is concrete) - `ServerSentEvent[Item | None]` allows optional data; bare `ServerSentEvent` is fully backward compatible (`Data=Any`) - Added `get_sse_data_type()` helper (uses Pydantic's `__pydantic_generic_metadata__`) to extract `Data` from a parameterized `ServerSentEvent[Data]` annotation - Routing layer now extracts `Data` from `ServerSentEvent[Data]` and uses it as `stream_item_type`, feeding it into the existing OpenAPI `contentSchema` pipeline - Added tutorial006 and corresponding snapshot test - Extended test_sse.py with generic SSE unit and app-level tests Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The previous commit added ServerSentEvent[Data] generic support and tutorial006 but did not add a corresponding section to the SSE docs. This adds the missing "Typed ServerSentEvent" section explaining the generic syntax, validation behavior, and OpenAPI contentSchema benefit. https://claude.ai/code/session_01GRv2sCmACvBQFX7fh7anWm
Bare `ServerSentEvent` (without a type parameter) now silently resolves to `ServerSentEvent[Any]`, so existing code and the `_check_data_exclusive` return annotation require no changes and pass mypy without `[type-arg]` errors. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
…e test Pydantic BaseModel subclasses always have __pydantic_generic_metadata__, so the `if not meta` early-return was dead code. Collapse it into a ternary and add a test for a plain (non-parameterized) ServerSentEvent subclass to reach the `not args` branch, bringing fastapi/sse.py to 100% coverage. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The test only fetched /openapi.json, leaving the generator body unreachable. Add a /stream request inside the same TestClient context so the yield executes, bringing tests/test_sse.py to 100% coverage. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Mirror of fastapi/fastapi#15191 by @benmosher