NodeJS Plugin Runtime (#53)

plugin-runtime/src/index.worker.ts

@@ -0,0 +1,64 @@
+import { readFileSync } from 'node:fs';
+import path from 'node:path';
+import { parentPort, workerData } from 'node:worker_threads';
+import { ParentToWorkerEvent } from './PluginHandle';
+import { PluginInfo } from './plugins';
+
+new Promise(async () => {
+  const { pluginDir } = workerData;
+  const pathMod = path.join(pluginDir, 'build/index.js');
+  const pathPkg = path.join(pluginDir, 'package.json');
+
+  const pkg = JSON.parse(readFileSync(pathPkg, 'utf8'));
+  const mod = (await import(pathMod)).default ?? {};
+
+  const info: PluginInfo = {
+    capabilities: [],
+    name: pkg['name'] ?? 'n/a',
+    dir: pluginDir,
+  };
+
+  if (typeof mod['pluginHookImport'] === 'function') {
+    info.capabilities.push('import');
+  }
+
+  if (typeof mod['pluginHookExport'] === 'function') {
+    info.capabilities.push('export');
+  }
+
+  if (typeof mod['pluginHookResponseFilter'] === 'function') {
+    info.capabilities.push('filter');
+  }
+
+  console.log('Loaded plugin', info.name, info.capabilities, info.dir);
+
+  function reply<T>(originalMsg: ParentToWorkerEvent, payload: T) {
+    parentPort!.postMessage({ payload, callbackId: originalMsg.callbackId });
+  }
+
+  function replyErr(originalMsg: ParentToWorkerEvent, error: unknown) {
+    parentPort!.postMessage({
+      error: String(error),
+      callbackId: originalMsg.callbackId,
+    });
+  }
+
+  parentPort!.on('message', (msg: ParentToWorkerEvent) => {
+    try {
+      const ctx = { todo: 'implement me' };
+      if (msg.name === 'run-import') {
+        reply(msg, mod.pluginHookImport(ctx, msg.payload));
+      } else if (msg.name === 'run-filter') {
+        reply(msg, mod.pluginHookResponseFilter(ctx, msg.payload));
+      } else if (msg.name === 'run-export') {
+        reply(msg, mod.pluginHookExport(ctx, msg.payload));
+      } else if (msg.name === 'info') {
+        reply(msg, info);
+      } else {
+        console.log('Unknown message', msg);
+      }
+    } catch (err: unknown) {
+      replyErr(msg, err);
+    }
+  });
+}).catch((err) => console.log('failed to boot plugin', err));