A consistency review of the alknet-http specs found two classes of
issues: internal contradictions from the mid-spec pivot (the to_openapi
gateway pattern landed in prose but not in cross-references), and a
systematic client→server assumption that only holds for the OpenAPI/MCP
case leaking into the WebTransport architecture.
Class 1 (internal contradictions):
- C1: to_openapi was half-refactored — body described the ADR-042
gateway pattern but the decisions table and ADR-036 still said
'paths mirror /{service}/{op}'. ADR-036's to_openapi clause is now
amended as superseded by ADR-042; the stale decisions row and README
Principle 2 are fixed.
- C2: the axum Router route list didn't include the 5 gateway endpoints
(/search, /schema, /call, /batch, /subscribe). Added them; clarified
/openapi.json as the gateway description doc; added gateway paths to
the decoy exclusion list.
- C3: ADR-034 §5 still talked about the 'h3/WebTransport deferral
bucket' that ADR-038 eliminated. Amended §5/Consequences/References
to drop the deferral framing (the auth-model decision stands; only
the 'when' wording was stale).
Class 2 (one-way direction assumption):
- C4/C5/C6: the WebTransport specs framed the session as browser→hub
one-way, when the call protocol is bidirectional and WebTransport is
a general ALPN transport substrate. New ADR-043 reframes WebTransport
as a bidirectional ALPN transport substrate (call protocol is the
first/canonical target; needs no WASM parser), names the call
protocol's bidirectionality over WebTransport sessions, and states
the inbound no-PeerId connection-local overlay as the mirror of
ADR-034 §2. webtransport.md is updated to reflect this framing;
ADR-040 is repositioned (not superseded) as the substrate's non-call-
ALPN mechanism.
- C7: the HTTP/1.1+HTTP/2 surface's one-directionality is now named as
a lossy consequence of HTTP request/response; WebTransport is named
as the surface that restores the bidirectional call model.
- C8: overview.md acknowledges the from/to direction model is
OpenAPI/MCP-specific, not a call-protocol property.
A review subagent pass on ADR-043 + webtransport.md found no critical
issues; warnings W1-W3 (residual browser-as-subject framing, ADR-009
rationale in spec, opening abstract tone) and suggestions S2/S4/S5
were addressed.
The to_openapi spec was describing one OpenAPI path per alknet operation
— the inverse of from_openapi. That inverse is genuinely messy: the call
protocol's input is a flat JSON object, and generating a traditional
OpenAPI path entry (POST /fs/{path} with path param, body, query params)
requires reverse-engineering which fields are path/query/body — metadata
the call protocol doesn't carry. The three options (leaky HTTP metadata
on OperationSpec, fragile heuristics, manual annotation) are all messy.
ADR-042 replaces this with the gateway pattern (same as ADR-041 for
to_mcp): to_openapi generates 5 fixed endpoints (search, schema, call,
batch, subscribe) that gate access to the full operation registry. The
input is always a flat JSON body — no path/query/body split to
reverse-engineer. JSON Schema is already in the OperationSpec.
The per-caller API surface is the key advantage: /search is
AccessControl-filtered, so the client sees only what it can call. The
Gitea failure mode (dumping admin ops to every caller in a static
OpenAPI doc) is structurally impossible — the per-caller surface is the
default, not an afterthought. OpenAPI has no per-caller filtering
concept; the gateway pattern provides it through /search.
Gateway endpoint set:
- /search -> services/list (AccessControl-filtered, names + descriptions)
- /schema -> services/schema (full OperationSpec)
- /call -> call.requested (Query/Mutation, flat JSON body)
- /batch -> multiple call.requested (correlated IDs)
- /subscribe -> call.requested (Subscription, SSE) — the one endpoint
the MCP gateway excludes (MCP is request/response; OpenAPI/SSE
supports streaming)
A traditional per-operation-paths projection is additive (a deployment
that wants the nice Swagger UI builds it with HTTP-specific metadata),
not a replacement. The gateway is the default.
http-adapters.md to_openapi section rewritten: the gateway endpoint
set, per-caller filtering, error fidelity on the /call endpoint, and
the additive traditional projection. The 'Why' section adds the
flat->structured and per-caller-surface rationale.
README/overview ADR tables and the top-level README current-state note
updated for ADR-042.
