Add ffi permission

This reverts commit 4a335dc936.

Procfile

@@ -1 +1 @@
-web: deno run --allow-net --allow-read --allow-env --unstable-worker-options deno_server.ts
+web: deno run --allow-net --allow-read --allow-write --allow-ffi --allow-env --unstable-worker-options deno_server.ts

deno.jsonc

@@ -1,6 +1,6 @@
 {
   "compilerOptions": {
-    "lib": ["deno.window", "deno.worker"]
+    "lib": ["deno.window", "deno.worker", "deno.ns"]
   },
   "lint": {
     "files": {
@@ -23,6 +23,6 @@
     }
   },
   "tasks": {
-    "start": "deno run --allow-net --allow-read --allow-env --unstable-worker-options deno_server.ts"
+    "start": "deno run --allow-net --allow-read --allow-write --allow-ffi --allow-env --unstable-worker-options deno_server.ts"
   }
 }

deno_server.ts

@@ -23,21 +23,35 @@ for (let i = 0; i < numWorkers; i++) {
   workerPool.push({ worker, inUse: false });
 }
 
+const requestQueue: ((
+  value:
+    | { worker: Worker; inUse: boolean }
+    | PromiseLike<{ worker: Worker; inUse: boolean }>
+) => void)[] = [];
+
 function getAvailableWorker() {
   return new Promise((resolve) => {
-    const check = () => {
-      const availableWorker = workerPool.find((w) => !w.inUse);
-      if (availableWorker) {
-        availableWorker.inUse = true;
-        resolve(availableWorker);
-      } else {
-        setTimeout(check, 100); // Check again in 100ms.
-      }
-    };
-    check();
+    const availableWorker = workerPool.find((w) => !w.inUse);
+    if (availableWorker) {
+      availableWorker.inUse = true;
+      resolve(availableWorker);
+    } else {
+      requestQueue.push(resolve);
+    }
   });
 }
 
+function releaseWorker(worker) {
+  if (requestQueue.length > 0) {
+    const nextRequest = requestQueue.shift();
+    if (nextRequest) {
+      nextRequest(worker);
+    }
+  } else {
+    worker.inUse = false;
+  }
+}
+
 async function handler(req: Request): Promise<Response> {
   if (req.method !== "POST" || new URL(req.url).pathname !== "/execute") {
     return new Response("Not Found", { status: 404 });
@@ -58,30 +72,45 @@ async function handler(req: Request): Promise<Response> {
     } = body;
 
     const executionPromise = new Promise((resolve, reject) => {
-      availableWorker.worker.onmessage = (e) => {
+      let timeoutId: number;
+
+      const cleanup = () => {
+        availableWorker.worker.removeEventListener("message", messageHandler);
+        availableWorker.worker.removeEventListener("error", errorHandler);
+        if (timeoutId) clearTimeout(timeoutId);
+      };
+
+      const messageHandler = (e: MessageEvent) => {
+        cleanup();
         resolve(e.data);
       };
-      availableWorker.worker.onerror = (e) => {
+
+      const errorHandler = (e: ErrorEvent) => {
+        cleanup();
         reject(new Error(`Worker error: ${e.message}`));
       };
+
+      timeoutId = setTimeout(() => {
+        cleanup();
+        reject(new Error("Timeout"));
+      }, TIMEOUT_MS);
+
+      availableWorker.worker.addEventListener("message", messageHandler);
+      availableWorker.worker.addEventListener("error", errorHandler);
+
+      availableWorker.worker.postMessage({ code, request, environment, name });
     });
 
-    const timeoutPromise = new Promise((_, reject) =>
-      setTimeout(() => reject(new Error("Timeout")), TIMEOUT_MS)
-    );
-
-    availableWorker.worker.postMessage({ code, request, environment, name });
-
     const startTime = performance.now();
     try {
-      const result = await Promise.race([executionPromise, timeoutPromise]);
+      const result = await executionPromise;
       return new Response(JSON.stringify(result), {
         headers: { "Content-Type": "application/json" },
       });
     } catch (err) {
       const executionTime = performance.now() - startTime;
       const payload = {
-        status: States.TIMEOUT,
+        status: err.message === "Timeout" ? States.TIMEOUT : "ERROR",
         result: err.message,
         logs: [],
         environment: environment,
@@ -95,7 +124,7 @@ async function handler(req: Request): Promise<Response> {
   } catch (e) {
     return new Response(`Bad Request: ${e.message}`, { status: 400 });
   } finally {
-    availableWorker.inUse = false; // Release the worker.
+    releaseWorker(availableWorker); // Release the worker.
   }
 }
 

worker.ts

@@ -1,4 +1,6 @@
 // isolator/worker.ts
+// No module cache to ensure fresh code for every execution.
+
 const States = Object.freeze({
   SUCCESS: "SUCCESS",
   NOT_A_FUNCTION: "NOT_A_FUNCTION",
@@ -50,7 +52,7 @@ self.onmessage = async (e) => {
         status
       );
 
-    // Use a data URL to import the user's code as an ES module.
+    // Use a data URL to import the user's code as a fresh ES module on every execution.
     const dataUrl = `data:text/javascript;base64,${btoa(
       unescape(encodeURIComponent(code))
     )}`;