build_registration now branches on op_type: Subscription ops register a
StreamingHandler (HandlerKind::Stream) via make_streaming_handler that
streams SSE response chunks as ResponseEnvelope::ok() items (one per
data: frame); Query/Mutation ops keep the existing Handler
(HandlerKind::Once) via forward(). Closes the gap where a from_openapi-
imported Subscription returned only the last SSE event.
- forward_stream(): non-async fn returning ResponseStream; sends the
request with Accept: text/event-stream, then streams SSE chunks via
stream::unfold over response.bytes_stream(), reusing parse_sse_frames
(multi-event, partial trailing, comments, multi-line data, BOM).
HTTP error (non-2xx) → single ResponseEnvelope::error(), stream ends;
SSE stream end → ResponseStream ends (→ call.completed on wire).
- Removed stream_subscription() (the collect-all placeholder that
truncated to the last event). parse_sse_frames stays (reused).
- Query/Mutation forwarding unchanged (existing forward() path).
- Tests: Subscription registration is HandlerKind::Stream; Query
registration is HandlerKind::Once; SSE subscription streams multiple
ResponseEnvelope::ok() (one per data: frame); HTTP error → single
error envelope; Query forwarding unchanged (single response).
Add the foundational types for ADR-049 streaming handlers:
- StreamingHandler, ResponseStream type aliases and HandlerKind enum
(Once | Stream) in registration.rs, with make_streaming_handler() helper
- CallError::invalid_operation_type() in wire.rs (sixth protocol code,
retryable: false)
- HandlerRegistration.handler flipped from Handler to HandlerKind;
HandlerRegistration::new() now takes HandlerKind
- OperationRegistryBuilder absorbs wrapping: with_local/with_leaf/
with_leaf_provenance wrap raw Handler in HandlerKind::Once for
Query/Mutation; new with_local_streaming/with_leaf_streaming take a
StreamingHandler and wrap in HandlerKind::Stream for Subscription.
Builder validates kind matches spec.op_type (mismatch = startup error)
- OperationRegistry::register() returns Result<(), String> with a clear
mismatch message; all call sites updated to handle the Result
- invoke() matches on HandlerKind: Once -> existing path; Stream ->
INVALID_OPERATION_TYPE error envelope (guards against silent
truncation; invoke_streaming() added in a downstream task)
- OverlayOperationEnv::invoke_with_policy matches on HandlerKind:
Once -> dispatch; Stream -> INVALID_OPERATION_TYPE (composition is
request/response-only)
- Migrated every HandlerRegistration::new() construction site (~95)
to wrap raw Handler in HandlerKind::Once(handler); the builder sites
are handled by the builder-absorbs-wrapping change
- Updated two websocket subscription tests that relied on Subscription
ops dispatching via invoke() to expect INVALID_OPERATION_TYPE
- Added unit tests for invoke/register validation and
make_streaming_handler
Parses OpenAPI 3.x documents into HandlerRegistration bundles with
reqwest-backed forwarding handlers that inject credentials from
OperationContext.capabilities (no-env-vars invariant, ADR-014).
Error codes are prefixed HTTP_<status> (ADR-023); ops are Internal
leaves with FromOpenAPI provenance (ADR-015/022). SSE subscriptions
are consumed via parseSSEFrames; JSON/text/binary response branching
mirrors the TS prior art.
