feat(npm): ship canonical Pyodide module worker (Phase 3c)

.gitignore

@@ -127,3 +127,5 @@ temp/
 /npm/pineforge_codegen/
 /npm/tables.json
 /npm/release.json
+/npm/transpile.worker.mjs
+/npm/glue.py

npm/index.mjs

@@ -1,6 +1,7 @@
 // Entry for @pineforge/codegen-pyodide. Resolves the packaged payload paths and
 // metadata so consumers (the app's build + Node oracle/grammar tooling) read
 // everything from this one dependency — no git submodule.
+import { readFileSync } from "node:fs";
 import { createRequire } from "node:module";
 import { dirname, join } from "node:path";
 import { fileURLToPath } from "node:url";
@@ -18,3 +19,12 @@ export const archivePath = join(HERE, `pineforge_codegen-${release.codegen}.tar.
 // so `import pineforge_codegen` resolves (oracle tests, grammar gen).
 export const sourceRoot = HERE;
 export const codegenSourceDir = join(HERE, "pineforge_codegen");
+
+// Absolute path to the shipped ESM module worker — consumers copy it into their
+// served /pyodide/ dir and load it via `new Worker(url, { type: "module" })`.
+export const workerPath = join(HERE, "transpile.worker.mjs");
+
+// Canonical Pyodide glue source (single source: gate/glue.py) — runPython'd to
+// define transpile_json. The worker embeds this verbatim; exported here too so
+// Node consumers (parity tests) run the exact same glue.
+export const glue = readFileSync(join(HERE, "glue.py"), "utf8");

npm/package.json

@@ -14,7 +14,9 @@
     "pineforge_codegen-*.tar.gz",
     "pineforge_codegen/**/*",
     "tables.json",
-    "release.json"
+    "release.json",
+    "transpile.worker.mjs",
+    "glue.py"
   ],
   "engines": {
     "node": ">=20"

scripts/build-npm-package.mjs

@@ -31,7 +31,7 @@ const release = JSON.parse(readFileSync(RELEASE, "utf8"));
 if (release.codegen !== VERSION) fail(`release.json codegen ${release.codegen} != VERSION ${VERSION}`);
 
 // 1. Clean payload (keep tracked manifest + index).
-for (const p of ["pineforge_codegen", "tables.json", "release.json"]) {
+for (const p of ["pineforge_codegen", "tables.json", "release.json", "glue.py", "transpile.worker.mjs"]) {
   rmSync(join(NPM, p), { recursive: true, force: true });
 }
 const versionedArchive = `pineforge_codegen-${VERSION}.tar.gz`;
@@ -55,6 +55,12 @@ const tablesJson = execFileSync("python3", [join(ROOT, "scripts", "dump-tables.p
 });
 writeFileSync(join(NPM, "tables.json"), tablesJson);
 
+// --- canonical glue + generated module worker (single source: gate/glue.py) ---
+const glueSrc = readFileSync(join(ROOT, "gate", "glue.py"), "utf8");
+writeFileSync(join(NPM, "glue.py"), glueSrc);
+const workerTemplate = readFileSync(join(ROOT, "scripts", "worker-template.mjs"), "utf8");
+writeFileSync(join(NPM, "transpile.worker.mjs"), workerTemplate.replace("__GLUE__", glueSrc));
+
 // 5. Sync npm/package.json version from VERSION.
 const pkgPath = join(NPM, "package.json");
 const pkg = JSON.parse(readFileSync(pkgPath, "utf8"));

scripts/worker-template.mjs

@@ -0,0 +1,49 @@
+// GENERATED by scripts/build-npm-package.mjs from gate/glue.py — DO NOT EDIT.
+// Canonical client-side Pyodide transpile worker, shipped by
+// @pineforge/codegen-pyodide. Consumers serve it from /pyodide/ and load it via:
+//   new Worker("/pyodide/transpile.worker.mjs", { type: "module" })
+// A real ESM module worker (string-URL load bypasses the bundler), so Pyodide
+// 314's module-worker requirement is satisfied. Mirrors the old in-app
+// transpile.worker.ts; protocol is identical (see app protocol.ts).
+import { loadPyodide } from "/pyodide/pyodide.mjs";
+
+const GLUE = `__GLUE__`;
+
+const post = (m) => self.postMessage(m);
+let transpileJson = null;
+
+async function init() {
+  try {
+    const pyodide = await loadPyodide({ indexURL: "/pyodide/" });
+    const manifestRes = await fetch("/pyodide/manifest.json", { cache: "no-cache" });
+    if (!manifestRes.ok) throw new Error(`fetch /pyodide/manifest.json: ${manifestRes.status}`);
+    const manifest = await manifestRes.json();
+    const archiveRes = await fetch(`/pyodide/${manifest.archive}`);
+    if (!archiveRes.ok) throw new Error(`fetch /pyodide/${manifest.archive}: ${archiveRes.status}`);
+    const buf = await archiveRes.arrayBuffer();
+    pyodide.unpackArchive(buf, "gztar", { extractDir: "/codegen" });
+    pyodide.runPython(GLUE);
+    const fn = pyodide.globals.get("transpile_json");
+    transpileJson = (source) => fn(source);
+    post({ type: "ready", codegenVersion: manifest.codegenVersion });
+  } catch (err) {
+    post({ type: "init-error", error: err instanceof Error ? err.message : String(err) });
+  }
+}
+
+const initPromise = init();
+
+self.onmessage = async (ev) => {
+  const { id, source } = ev.data;
+  await initPromise;
+  if (!transpileJson) {
+    post({ type: "crash", id, error: "pyodide failed to initialize" });
+    return;
+  }
+  try {
+    const result = JSON.parse(transpileJson(source));
+    post({ type: "result", id, result });
+  } catch (err) {
+    post({ type: "crash", id, error: err instanceof Error ? err.message : String(err) });
+  }
+};