Merge remote-tracking branch 'origin/master' into codex/trim-redundant-comments

# Conflicts:
#	packages/client/connection/src/index.ts
#	packages/host/webserver/tests/web-plugins.spec.ts

packages/client/connection/src/api-path.ts

@@ -0,0 +1,8 @@
+/**
+ * The /api URL prefix — single source for both halves of the web transport.
+ * The node half registers this prefix on the web server; browser-side path
+ * literals currently live in the apiproxy client layer (out of scope here).
+ */
+
+/** Route prefix owning every api request (`/api` and `/api/<anything>`). */
+export const API_PATH = '/api'

packages/client/connection/src/http-bridge.ts

@@ -0,0 +1,59 @@
+/**
+ * node:http ↔ WHATWG fetch bridge for the /api transport (host side of the
+ * web carrier; the fetch-shaped handler itself is transport-agnostic).
+ */
+
+import type { IncomingMessage, ServerResponse } from 'node:http'
+
+/**
+ * Bridge one node:http request to the fetch-shaped handler (client close
+ * aborts; SSE bodies stream out chunk by chunk).
+ * @param req - incoming node:http request (fully read before dispatch).
+ * @param res - node:http response the bridge writes and owns to completion.
+ * @param apiHandler - fetch-shaped API carrier the request is dispatched to.
+ */
+export async function bridge(req: IncomingMessage, res: ServerResponse, apiHandler: { fetch: typeof fetch }): Promise<void> {
+  const abort = new AbortController()
+  // Client-disconnect detection MUST hang off the response, not the request:
+  // since Node 16, IncomingMessage 'close' fires as soon as the request body is
+  // fully consumed (immediately for a bodyless GET), which would abort every SSE
+  // stream right after open. ServerResponse 'close' fires on connection teardown;
+  // writableEnded distinguishes a normal end() from the client going away.
+  res.on('close', () => {
+    if (!res.writableEnded) abort.abort()
+  })
+  const chunks: Buffer[] = []
+  for await (const chunk of req) chunks.push(chunk as Buffer)
+  /* v8 ignore next 3 -- `??` arms: node:http always sets url/method on server
+  requests; the fields are only optional on the client-side IncomingMessage type */
+  const request = new Request(new URL(req.url ?? '/', 'http://dsh.internal'), {
+    method: req.method ?? 'GET',
+    headers: Object.fromEntries(Object.entries(req.headers).filter(([, v]) => typeof v === 'string') as [string, string][]),
+    ...chunks.length > 0 ? { body: Buffer.concat(chunks) } : {},
+    signal: abort.signal,
+  })
+  const response = await apiHandler.fetch(request)
+  res.writeHead(response.status, Object.fromEntries(response.headers.entries()))
+  if (response.body === null) {
+    res.end()
+    return
+  }
+  for await (const chunk of response.body) {
+    // Backpressure: a false return means the socket buffer is full — wait for drain
+    // instead of buffering unboundedly (slow/suspended SSE consumers). 'close' also
+    // resolves so a mid-wait disconnect can't park this loop forever; the close
+    // handler above aborts the handler stream, which then ends the iteration.
+    if (!res.write(chunk)) {
+      await new Promise<void>((resolve) => {
+        const done = (): void => {
+          res.off('drain', done)
+          res.off('close', done)
+          resolve()
+        }
+        res.once('drain', done)
+        res.once('close', done)
+      })
+    }
+  }
+  res.end()
+}

packages/client/connection/src/index.ts

@@ -1,4 +1,29 @@
-/** Host loader entry for the browser wire client exported from `./client`. */
+/** Host HTTP bridge for browser-client RPC. */
+import type { Context } from 'cordis'
+// Activates the httpServer Context merge used below.
+import type { WebRoute } from '@deepseek-ai/dsh-host-webserver'
+import { toFetchHandler } from '@deepseek-ai/dsh-host-apiproxy'
+import { API_PATH } from './api-path.ts'
+import { bridge } from './http-bridge.ts'
 
-/** Host plugin body — no host-side behavior for the connection plugin. */
-export function apply(_ctx: unknown): void {}
+export { API_PATH } from './api-path.ts'
+
+/** Stable Cordis plugin name. */
+export const name = 'client-connection'
+
+/** Services required before mounting the route. */
+export const inject = ['httpServer', 'apiProxy']
+
+/**
+ * Mounts the API gateway under the browser transport prefix.
+ * @param ctx - Host plugin context.
+ */
+export function apply(ctx: Context): void {
+  const apiHandler = toFetchHandler(ctx.apiProxy)
+  const route: WebRoute = {
+    kind: 'prefix',
+    path: API_PATH,
+    handler: (req, res) => bridge(req, res, apiHandler),
+  }
+  ctx.effect(() => ctx.httpServer.register(route), 'client-connection: /api route')
+}

packages/client/connection/src/invariant.ts

@@ -15,10 +15,11 @@ export const name = 'client-connection-invariant'
 export const inject = ['invariants']
 
 /**
- * No runtime invariant: the pure wire layer emits no cordis events and owns no
+ * No runtime invariant: the wire layer emits no cordis events and owns no
  * mutable cross-plugin relation — stream/reconnect sequencing is exercised
- * directly by its behavior specs, and rpcId round-trip discipline is owned by
- * the apiproxy contract layer.
+ * directly by its behavior specs, rpcId round-trip discipline is owned by the
+ * apiproxy contract layer, and the node half's single route registration's
+ * register/dispose symmetry is audited by the webserver package's invariant.
  */
 const install: InvariantInstaller = () => {}