fix: add call.completed signaling (M-04) and forward SSE requestBody (L-04)

docs/reviews/pre-release-review-2025-05-16.md

@@ -2,7 +2,7 @@
 
 **Date:** 2026-05-16
 **Scope:** Full codebase review for issues that would impact downstream hub/spoke implementations
-**Status:** C-01 through C-05, H-01 through H-06, M-01 through M-03, M-05 through M-08, and L-01 through L-05 resolved. M-04 (call.completed signaling) and L-04 (SSE GET requestBody) deferred. M-02 resolved (subpath export added, OpenAPI re-exported from main entry removed).
+**Status:** C-01 through C-05, H-01 through H-06, M-01 through M-08, and L-01 through L-05 resolved. L-04 resolved.
 
 ---
 
@@ -129,13 +129,11 @@ Both adapters have access to version information (MCP server info, OpenAPI `info
 
 `CallRequestedEvent` schema now has both `deadline?: number` and `idleTimeout?: number` as optional fields. `PendingRequestMap.subscribe()` accepts `{ idleTimeout }` instead of `{ deadline }`. The idle timer is correctly reset on each event using the stored `idleTimeout` value.
 
-### M-04. No unsubscribe/completion signaling in call protocol
+### M-04. No unsubscribe/completion signaling in call protocol ✅ RESOLVED
 
-**File:** `src/call.ts:298-301`
+**File:** `src/call.ts`
 
-**Status:** DEFERRED — will be implemented in a dedicated session due to protocol-level impact.
+**Resolution:** Added `call.completed` event type to the call protocol. When a subscription's async generator finishes naturally, `buildCallHandler` now calls `callMap.complete(requestId)` which publishes a `call.completed` event. The `PendingRequestMap` handles this event by closing the consumer's Repeater iterator (for subscriptions) or rejecting the pending promise (for calls). Added `CallCompletedEvent` type and schema, `complete()` method on `PendingRequestMap`, and a pubsub listener for `call.completed` in `setupSubscriptions()`. The `consumerStopped` flag is set before `stop()` to prevent spurious `call.aborted` events.
-
-When a subscription ends (the `for await` loop completes), `buildCallHandler` simply stops calling `callMap.respond()`. There is no `call.completed` or `call.finished` event type to explicitly signal subscription completion. The consumer must detect iterator completion, which works with `Repeater` but may not work with all pubsub implementations.
 
 ### M-05. mapError uses fragile message.includes(code) matching ✅ RESOLVED
 
@@ -177,11 +175,11 @@ When a subscription ends (the `for await` loop completes), `buildCallHandler` si
 
 **Resolution:** Added `logger.warn()` call when the fallback `Type.Unknown()` is reached, logging the unrecognized schema via `JSON.stringify()`. Uses `@logtape/logtape` with category `"operations:from_schema"`, matching the existing pattern.
 
-### L-04. from_openapi.ts SSE GET includes requestBody handling
+### L-04. from_openapi.ts SSE handler now forwards requestBody ✅ RESOLVED
 
 **File:** `src/from_openapi.ts`
 
-**Status:** NOTED — The `else if (key === "body")` branch in the SSE handler silently accepts but does not forward body parameters. This is intentional for unusual SSE-over-POST use cases. No action needed; the behavior is self-documenting from the code structure.
+**Resolution:** The SSE subscription handler previously had an empty `else if (key === "body")` branch that silently dropped body parameters. Fixed by adding `body` variable extraction and forwarding it as a JSON request body (with `Content-Type: application/json` header) when present. This correctly supports SSE-over-POST patterns while preserving GET-without-body behavior for standard SSE endpoints.
 
 ### L-05. No convenience registerAll methods on MCP or OpenAPI adapters ✅ RESOLVED
 

src/call.ts

@@ -30,6 +30,9 @@ export const CallEventSchema = {
     requestId: Type.String(),
     output: ResponseEnvelopeSchema,
   }),
+  "call.completed": Type.Object({
+    requestId: Type.String(),
+  }),
   "call.aborted": Type.Object({
     requestId: Type.String(),
   }),
@@ -43,15 +46,17 @@ export const CallEventSchema = {
 
 export type CallRequestedEvent = Static<typeof CallEventSchema["call.requested"]>;
 export type CallRespondedEvent = Static<typeof CallEventSchema["call.responded"]>;
+export type CallCompletedEvent = Static<typeof CallEventSchema["call.completed"]>;
 export type CallAbortedEvent = Static<typeof CallEventSchema["call.aborted"]>;
 export type CallErrorEvent = Static<typeof CallEventSchema["call.error"]>;
-export type CallEventMapValue = CallRequestedEvent | CallRespondedEvent | CallAbortedEvent | CallErrorEvent;
+export type CallEventMapValue = CallRequestedEvent | CallRespondedEvent | CallCompletedEvent | CallAbortedEvent | CallErrorEvent;
 
 export const CallEventMap = CallEventSchema;
 
 type CallPubSubMap = {
   "call.requested": CallRequestedEvent;
   "call.responded": CallRespondedEvent;
+  "call.completed": CallCompletedEvent;
   "call.aborted": CallAbortedEvent;
   "call.error": CallErrorEvent;
 };
@@ -141,6 +146,27 @@ export class PendingRequestMap {
       logger.error(`call.error listener error: ${error instanceof Error ? error.message : String(error)}`);
     });
 
+    const completedIter = this.pubsub.subscribe("call.completed", "");
+    (async () => {
+      for await (const envelope of completedIter) {
+        const completed = envelope.payload;
+        const entry = this.entries.get(completed.requestId);
+        if (!entry) continue;
+
+        if (entry.type === "subscribe") {
+          if (entry.state.timer) clearTimeout(entry.state.timer);
+          entry.state.consumerStopped = true;
+          entry.state.stop();
+        } else {
+          if (entry.pending.timer) clearTimeout(entry.pending.timer);
+          entry.pending.reject(new CallError(InfrastructureErrorCode.ABORTED, `Request ${completed.requestId} completed without response`));
+        }
+        this.entries.delete(completed.requestId);
+      }
+    })().catch((error) => {
+      logger.error(`call.completed listener error: ${error instanceof Error ? error.message : String(error)}`);
+    });
+
     const abortedIter = this.pubsub.subscribe("call.aborted", "");
     (async () => {
       for await (const envelope of abortedIter) {
@@ -267,6 +293,10 @@ export class PendingRequestMap {
     });
   }
 
+  complete(requestId: string): void {
+    this.pubsub.publish("call.completed", "", { requestId });
+  }
+
   abort(requestId: string): void {
     const entry = this.entries.get(requestId);
     if (!entry) return;
@@ -312,6 +342,7 @@ export function buildCallHandler(config: CallHandlerConfig): CallHandler {
         for await (const envelope of subscribe(registry, operationId, input, context)) {
           callMap.respond(requestId, envelope);
         }
+        callMap.complete(requestId);
       } else {
         const envelope = await registry.execute(operationId, input, context);
         callMap.respond(requestId, envelope);

src/from_openapi.ts

@@ -334,11 +334,13 @@ function createHTTPOperation(
 
       let urlPath = path;
       const queryParams: Record<string, string> = {};
+      let body: unknown = undefined;
 
       for (const [key, value] of Object.entries(inputObj)) {
         if (path.includes(`{${key}}`)) {
           urlPath = urlPath.replace(`{${key}}`, encodeURIComponent(String(value)));
         } else if (key === "body") {
+          body = value;
         } else {
           queryParams[key] = String(value);
         }
@@ -351,12 +353,14 @@ function createHTTPOperation(
 
       const headers: Record<string, string> = {
         ...authHeaders,
+        ...(body ? { "Content-Type": "application/json" } : {}),
         "Accept": "text/event-stream",
       };
 
       const response = await httpClient(url.toString(), {
         method: method.toUpperCase(),
         headers,
+        body: body ? JSON.stringify(body) : undefined,
         signal: config.timeout ? AbortSignal.timeout(config.timeout) : undefined,
       });
 

src/index.ts

@@ -11,7 +11,7 @@ export type { OperationManifest, ScannerFS } from "./scanner.js";
 export { CallError, InfrastructureErrorCode, mapError } from "./error.js";
 export type { CallErrorCode } from "./error.js";
 export { PendingRequestMap, buildCallHandler } from "./call.js";
-export type { CallEventMap, CallEventMapValue, CallRequestedEvent, CallRespondedEvent, CallAbortedEvent, CallErrorEvent, CallHandler, CallHandlerConfig } from "./call.js";
+export type { CallEventMap, CallEventMapValue, CallRequestedEvent, CallRespondedEvent, CallCompletedEvent, CallAbortedEvent, CallErrorEvent, CallHandler, CallHandlerConfig } from "./call.js";
 export { checkAccess, enforceAccess } from "./access.js";
 export { subscribe } from "./subscribe.js";
 export { defaultAdapter, zodAdapter, valibotAdapter } from "./from_typemap.js";

test/call.test.ts

@@ -1162,7 +1162,6 @@ describe("CallHandler SUBSCRIPTION dispatch", () => {
     const consumePromise = (async () => {
       try {
         for await (const _ of subscribeIter) {
-          // should not reach
         }
       } catch (error) {
         caughtError = error;
@@ -1185,3 +1184,148 @@ describe("CallHandler SUBSCRIPTION dispatch", () => {
     expect((caughtError as CallError).code).toBe(InfrastructureErrorCode.ACCESS_DENIED);
   });
 });
+
+describe("call.completed signaling", () => {
+  it("complete() closes subscription iterator", async () => {
+    const map = new PendingRequestMap();
+    let completedRequestId: string | undefined;
+
+    const completedIter = map["pubsub"].subscribe("call.completed", "");
+    const completedPromise = (async () => {
+      for await (const envelope of completedIter) {
+        completedRequestId = envelope.payload.requestId;
+        break;
+      }
+    })();
+
+    const subscribeIter = map.subscribe("test.stream", {});
+    let iterationCompleted = false;
+
+    const consumePromise = (async () => {
+      for await (const _ of subscribeIter) {
+      }
+      iterationCompleted = true;
+    })();
+
+    await new Promise((r) => setTimeout(r, 20));
+    const requestId = [...map["entries"].keys()][0];
+
+    map.respond(requestId, localEnvelope("event1", "test.stream"));
+
+    await new Promise((r) => setTimeout(r, 20));
+    map.complete(requestId);
+
+    await consumePromise;
+    await completedPromise;
+
+    expect(iterationCompleted).toBe(true);
+    expect(completedRequestId).toBe(requestId);
+    expect(map.getPendingCount()).toBe(0);
+  });
+
+  it("buildCallHandler publishes call.completed when subscription generator finishes", async () => {
+    const registry = new OperationRegistry();
+    registry.register({
+      name: "finite",
+      namespace: "test",
+      version: "1.0.0",
+      type: OperationType.SUBSCRIPTION,
+      description: "finite stream",
+      inputSchema: Type.Object({}),
+      outputSchema: Type.Unknown(),
+      accessControl: { requiredScopes: [] },
+      handler: async function* (_input: unknown, _context: unknown) {
+        yield "a";
+        yield "b";
+      },
+    });
+
+    const callMap = new PendingRequestMap();
+    const handler = buildCallHandler({ registry, callMap });
+
+    let completedRequestId: string | undefined;
+    const completedIter = callMap["pubsub"].subscribe("call.completed", "");
+    const completedPromise = (async () => {
+      for await (const envelope of completedIter) {
+        completedRequestId = envelope.payload.requestId;
+        break;
+      }
+    })();
+
+    const subscribeIter = callMap.subscribe("test.finite", {});
+    const results: ResponseEnvelope[] = [];
+    const consumePromise = (async () => {
+      for await (const envelope of subscribeIter) {
+        results.push(envelope);
+      }
+    })();
+
+    await new Promise((r) => setTimeout(r, 20));
+    const requestId = [...callMap["entries"].keys()][0];
+
+    await handler({
+      requestId,
+      operationId: "test.finite",
+      input: {},
+    });
+
+    await consumePromise;
+    await completedPromise;
+
+    expect(results).toHaveLength(2);
+    expect(results[0].data).toBe("a");
+    expect(results[1].data).toBe("b");
+    expect(completedRequestId).toBe(requestId);
+    expect(callMap.getPendingCount()).toBe(0);
+  });
+
+  it("complete() on a call entry rejects the pending promise", async () => {
+    const map = new PendingRequestMap();
+
+    let completedRequestId: string | undefined;
+    const completedIter = map["pubsub"].subscribe("call.completed", "");
+    const completedPromise = (async () => {
+      for await (const envelope of completedIter) {
+        completedRequestId = envelope.payload.requestId;
+        break;
+      }
+    })();
+
+    const callPromise = map.call("test.op", {});
+    const requestId = [...map["entries"].keys()][0];
+
+    map.complete(requestId);
+
+    await completedPromise;
+    expect(completedRequestId).toBe(requestId);
+
+    try {
+      await callPromise;
+      expect.fail("Should have thrown");
+    } catch (error) {
+      expect(error).toBeInstanceOf(CallError);
+      expect((error as CallError).code).toBe(InfrastructureErrorCode.ABORTED);
+      expect((error as CallError).message).toContain("completed without response");
+    }
+
+    expect(map.getPendingCount()).toBe(0);
+  });
+
+  it("complete() with invalid requestId still publishes event", async () => {
+    const map = new PendingRequestMap();
+
+    let completedReceived = false;
+    const completedIter = map["pubsub"].subscribe("call.completed", "");
+    const completedPromise = (async () => {
+      for await (const envelope of completedIter) {
+        completedReceived = true;
+        break;
+      }
+    })();
+
+    map.complete("nonexistent-id");
+
+    await completedPromise;
+    expect(completedReceived).toBe(true);
+  });
+});

test/from_openapi.test.ts

@@ -579,7 +579,6 @@ describe("FromOpenAPI SUBSCRIPTION handler", () => {
 
     try {
       for await (const _ of handler({}, {} as any)) {
-        // should not reach
       }
       expect.fail("Expected CallError");
     } catch (error) {
@@ -588,4 +587,112 @@ describe("FromOpenAPI SUBSCRIPTION handler", () => {
       expect((error as CallError).message).toContain("HTTP 500");
     }
   });
+
+  it("SSE handler forwards body in request when provided", async () => {
+    const sseStream = "data: {\"ok\":true}\n\n";
+    const encoder = new TextEncoder();
+
+    const reader = {
+      read: vi.fn()
+        .mockResolvedValueOnce({ done: false, value: encoder.encode(sseStream) })
+        .mockResolvedValueOnce({ done: true, value: undefined }),
+      releaseLock: vi.fn(),
+    };
+
+    const fetchMock = vi.fn().mockResolvedValue({
+      ok: true,
+      status: 200,
+      statusText: "OK",
+      headers: new Headers({ "Content-Type": "text/event-stream" }),
+      body: { getReader: () => reader },
+    });
+    globalThis.fetch = fetchMock;
+
+    const specWithBody = {
+      openapi: "3.0.0",
+      info: { title: "Test", version: "1.0.0" },
+      paths: {
+        "/events": {
+          post: {
+            operationId: "postEvents",
+            description: "Post and stream events",
+            requestBody: {
+              content: {
+                "application/json": {
+                  schema: { type: "object", properties: { filter: { type: "string" } } },
+                },
+              },
+            },
+            responses: {
+              "200": {
+                content: {
+                  "text/event-stream": {
+                    schema: { type: "object", properties: { ok: { type: "boolean" } } },
+                  },
+                },
+              },
+            },
+          },
+        },
+      },
+    };
+
+    const ops = FromOpenAPI(specWithBody as any, config);
+    const postEvents = ops.find((o) => o.name === "postEvents")!;
+    const handler = postEvents.handler as SubscriptionHandler<unknown, unknown, unknown>;
+
+    const results: unknown[] = [];
+    for await (const value of handler({ body: { filter: "important" } }, {} as any)) {
+      results.push(value);
+    }
+
+    expect(fetchMock).toHaveBeenCalledTimes(1);
+    const fetchArgs = fetchMock.mock.calls[0];
+    expect(fetchArgs[1].method).toBe("POST");
+    expect(fetchArgs[1].body).toBe(JSON.stringify({ filter: "important" }));
+    expect(fetchArgs[1].headers["Content-Type"]).toBe("application/json");
+
+    expect(results).toHaveLength(1);
+    if (isResponseEnvelope(results[0])) {
+      expect(results[0].data).toEqual({ ok: true });
+    }
+  });
+
+  it("SSE handler does not send body when input has no body key", async () => {
+    const sseStream = "data: {\"event\":\"ping\"}\n\n";
+    const encoder = new TextEncoder();
+
+    const reader = {
+      read: vi.fn()
+        .mockResolvedValueOnce({ done: false, value: encoder.encode(sseStream) })
+        .mockResolvedValueOnce({ done: true, value: undefined }),
+      releaseLock: vi.fn(),
+    };
+
+    const fetchMock = vi.fn().mockResolvedValue({
+      ok: true,
+      status: 200,
+      statusText: "OK",
+      headers: new Headers({ "Content-Type": "text/event-stream" }),
+      body: { getReader: () => reader },
+    });
+    globalThis.fetch = fetchMock;
+
+    const ops = FromOpenAPI(simpleSpec as any, config);
+    const streamEvents = ops.find((o) => o.name === "streamEvents")!;
+    const handler = streamEvents.handler as SubscriptionHandler<unknown, unknown, unknown>;
+
+    const results: unknown[] = [];
+    for await (const value of handler({}, {} as any)) {
+      results.push(value);
+    }
+
+    expect(fetchMock).toHaveBeenCalledTimes(1);
+    const fetchArgs = fetchMock.mock.calls[0];
+    expect(fetchArgs[1].method).toBe("GET");
+    expect(fetchArgs[1].body).toBeUndefined();
+    expect(fetchArgs[1].headers["Content-Type"]).toBeUndefined();
+
+    expect(results).toHaveLength(1);
+  });
 });