---
id: adapter-from-jsonschema
name: from_jsonschema single-endpoint adapter
status: completed
depends_on: [client-http-host]
scope: narrow
risk: low
impact: component
level: implementation
tags: [adapters, phase-3]
---

## Description

Port `adapters/from_jsonschema.rs` from
`/workspace/@alkdev/alknet/crates/alknet-http/src/adapters/from_jsonschema.rs`
per ADR-066: caller supplies OperationSpec + HttpServiceConfig + path
template + method; one HandlerRegistration with a reqwest forwarding
handler (same shape as from_openapi's), FromJsonSchema provenance
(leaf, Internal default). Sub op type → StreamingHandler expecting
text/event-stream. Shares the forwarding-handler code path with
from_openapi.

## Acceptance Criteria

- [x] Adapter ported; one registration per call, correct provenance
- [x] Forwarding round-trip test against a local mock server
- [x] `cargo test` passes

## References

- docs/architecture/decisions/066-from-jsonschema-as-http-adapter.md
- docs/architecture/http-adapters.md (§from_jsonschema)
- alkcall ADR-027 (FromJsonSchema provenance)

## Notes

> Agent fills during implementation.

## Summary

Ported `src/adapters/from_jsonschema.rs` per ADR-066, plus the shared
forwarding core it depends on:

- `src/adapters/forward.rs`: extracted from old from_openapi —
  HttpServiceConfig/HttpAuthScheme, build_request (path templates,
  query split, body key, credential injection from
  OperationContext.capabilities), forward (2xx -> JSON/text/bytes
  envelope; non-2xx -> declared code or HTTP_<status>), forward_stream
  (SSE -> ResponseEnvelope stream, ADR-049), parse_sse_frames.
  Pre-positions the from_openapi port to reuse the same core.
- `src/adapters/from_jsonschema.rs`: FromJsonSchema OperationAdapter —
  one HandlerRegistration per call (spec + path template + method),
  FromJsonSchema provenance (leaf, composition_authority None,
  scoped_env None, Internal default), Sub op type -> HandlerKind::Stream
  expecting text/event-stream.

Adaptations for alkcall 0.1.1: OperationType::Sub (not Subscription),
adapter imports via alkcall::client::{AdapterError, OperationAdapter}.

11 tests: registration shape, handler kinds (Query/Sub/Mutation),
build_request bearer-from-capabilities + path/query split, forwarding
round-trip vs local mock server (200/404/500), SSE subscription stream,
no-env-vars invariant. 106 lib tests green.