One SDK per runtime: a bundle's SDK import resolves to the runtime's copy (hq issue 209)

A bundle carries its dependencies, the SDK among them; imported in-process that copy was a
second SDK with its own tool registry, so a bundle registered its tools into a list the
runtime never read and served nothing, silently. A resolve hook (module.registerHooks, in
thread; module.register is deprecated from Node 26) now sends every import of
@novox/mesh-sdk, from whichever bundle, to the runtime's own copy: one registry, one broker.
The test loads a bundle from a directory holding its own SDK copy and sees its tool served.

node-tools/src/runtime.ts

@@ -9,8 +9,9 @@
 // and the per-module shape is the list with one entry. A bundle that fails to import is named —
 // in the log and in what `tools` answers for it — and the others serve.
 
-import { pathToFileURL } from "node:url";
-import { resolve } from "node:path";
+import { fileURLToPath, pathToFileURL } from "node:url";
+import { dirname, join, resolve } from "node:path";
+import { existsSync, readFileSync } from "node:fs";
 import { registerHooks } from "node:module";
 import { useBroker } from "@novox/mesh-sdk/messaging";
 import { collectTools, toolKey, type ToolDefinition } from "@novox/mesh-sdk/tools";
@@ -331,17 +332,49 @@ const SDK = "@novox/mesh-sdk";
  * one registry, one broker — the runtime's. Everything else a bundle carries resolves from the
  * bundle's own tree, as before. A launched bundle (ADR 0188) is another process and is untouched.
  *
- * Installed once, in-thread, before the first bundle is imported; the hook sees every import after.
+ * Installed once, in-thread, before the first bundle is imported; the hook sees every import after,
+ * `require` included. A bundle whose own copy is another version than the runtime's is said once,
+ * so a tool failing against the runtime's SDK points at the bundle rather than at the runtime.
  */
 function oneSdk(): void {
   if (sdkHooked) return;
-  sdkHooked = true;
   registerHooks({
     resolve(specifier, context, next) {
       if (specifier === SDK || specifier.startsWith(SDK + "/")) {
+        if (context.parentURL) sayOtherSdk(context.parentURL);
         return next(specifier, { ...context, parentURL: import.meta.url });
       }
       return next(specifier, context);
     },
   });
+  sdkHooked = true;
+}
+
+const sdkSaid = new Set<string>();
+/** The version of the SDK copy nearest a file, by its package.json, or nothing when the file has none above it. */
+function sdkVersionNear(fileURL: string): { dir: string; version: string } | undefined {
+  let dir = dirname(fileURLToPath(fileURL));
+  for (;;) {
+    const pkg = join(dir, "node_modules", SDK, "package.json");
+    if (existsSync(pkg)) {
+      try {
+        return { dir, version: String((JSON.parse(readFileSync(pkg, "utf8")) as { version?: string }).version ?? "?") };
+      } catch {
+        return { dir, version: "?" };
+      }
+    }
+    const up = dirname(dir);
+    if (up === dir) return undefined;
+    dir = up;
+  }
+}
+function sayOtherSdk(parentURL: string): void {
+  if (!parentURL.startsWith("file:")) return;
+  const own = sdkVersionNear(import.meta.url);
+  const theirs = sdkVersionNear(parentURL);
+  if (!theirs || !own || theirs.dir === own.dir || sdkSaid.has(theirs.dir)) return;
+  sdkSaid.add(theirs.dir);
+  if (theirs.version !== own.version) {
+    console.log(`[mesh-tools] ${theirs.dir} carries ${SDK} ${theirs.version}; this runtime's is ${own.version}, and the bundle speaks to the runtime's`);
+  }
 }

node-tools/test/node-runtime.test.ts

@@ -11,7 +11,7 @@
 import assert from "node:assert/strict";
 import { test } from "node:test";
 import { fileURLToPath } from "node:url";
-import { cpSync, mkdtempSync, realpathSync, rmSync, writeFileSync } from "node:fs";
+import { cpSync, mkdirSync, mkdtempSync, realpathSync, rmSync, writeFileSync } from "node:fs";
 import { join } from "node:path";
 import { tmpdir } from "node:os";
 import { connect, StringCodec } from "nats";
@@ -199,36 +199,45 @@ test("the node's runtime serves five modules' bundles on one credential — two
 test("a bundle carrying its own copy of the SDK registers into the runtime's registry, and its tools are served (issue 209)", async (t) => {
   if (!url) return t.skip("MESH_TEST_NATS unset");
   resetTools();
+  let dir = "";
+  let stop = () => {};
+  const closing: Array<() => Promise<void>> = [];
+  const said: string[] = [];
+  const log = console.log;
+  try {
     // A bundle as the toolchain packs one: its compiled entrypoint, a package.json saying ES modules,
-  // and its dependencies copied in — the SDK among them, a second copy beside the runtime's own.
-  const dir = mkdtempSync(join(tmpdir(), "mesh-bundle-"));
+    // and its dependencies copied in — the SDK among them, a second copy beside the runtime's own,
+    // and a dependency of the bundle's own that the runtime does not carry.
+    dir = mkdtempSync(join(tmpdir(), "mesh-bundle-"));
     const sdk = realpathSync(fileURLToPath(new URL("../node_modules/@novox/mesh-sdk/", import.meta.url)));
     cpSync(sdk, join(dir, "node_modules", "@novox", "mesh-sdk"), { recursive: true });
+    mkdirSync(join(dir, "node_modules", "zeta-flavour"), { recursive: true });
+    writeFileSync(join(dir, "node_modules", "zeta-flavour", "package.json"), '{"name":"zeta-flavour","type":"module","main":"index.js"}\n');
+    writeFileSync(join(dir, "node_modules", "zeta-flavour", "index.js"), 'export const flavour = "the bundle\'s own";\n');
     writeFileSync(join(dir, "package.json"), '{"type":"module","private":true}\n');
     writeFileSync(join(dir, "index.js"),
       'import { registerModuleTools } from "@novox/mesh-sdk/tools";\n' +
-    'registerModuleTools("zeta", () => [{ name: "probe", description: "answers", input: {}, run: async () => ({ zeta: true }) }]);\n');
+      'import { flavour } from "zeta-flavour";\n' +
+      'registerModuleTools("zeta", () => [{ name: "probe", description: "answers", input: {}, run: async () => ({ zeta: true, flavour }) }]);\n');
     const mesh = await aMesh();
+    closing.push(() => mesh.close());
     await mesh.issue(membershipOf("zeta", "anchor"));
     const credential = { url, node: "anchor", module: "node-tools" };
     const nodeTools = await connectNats(credential);
+    closing.push(() => nodeTools.close());
     const asker = await connectNats({ url, module: "console", node: "workstation" });
-  const said: string[] = [];
-  const log = console.log;
+    closing.push(() => asker.close());
     console.log = (...a: unknown[]) => said.push(a.join(" "));
-  let stop = () => {};
-  try {
     stop = await runTools({ broker: nodeTools, credential, serves: [{ module: "zeta", entrypoints: [join(dir, "index.js")] }] });
     console.log = log;
     assert.ok(said.some((s) => /serving 1 tool\(s\) for 1 module\(s\): zeta\.probe/.test(s)), said.join("\n"));
-    assert.deepEqual((await callTool(asker, "zeta.probe@anchor", {})).result, { zeta: true });
+    // The SDK is the runtime's (the registration arrived); the bundle's other dependency is its own.
+    assert.deepEqual((await callTool(asker, "zeta.probe@anchor", {})).result, { zeta: true, flavour: "the bundle's own" });
   } finally {
     console.log = log;
     stop();
-    await asker.close();
-    await nodeTools.close();
-    await mesh.close();
-    rmSync(dir, { recursive: true, force: true });
+    for (const close of closing.reverse()) await close();
+    if (dir) rmSync(dir, { recursive: true, force: true });
     resetTools();
   }
 });