feat: render threading

src/core/blitzkrieg/jsxToPngThreaded.ts

@@ -0,0 +1,9 @@
+import jsxToSvg from './jsxToSvg';
+import { svgToPngThreaded } from './svgToPngThreaded';
+
+export default async function jsxToPngThreaded(jsx: JSX.Element) {
+  const svg = await jsxToSvg(jsx);
+  const png = await svgToPngThreaded(svg);
+
+  return png;
+}

src/core/blitzkrieg/svgToPngThreaded.ts

@@ -0,0 +1,42 @@
+import { Worker } from 'worker_threads';
+
+const MAX_WORKERS = 3;
+
+const workers = [...Array(MAX_WORKERS)].map(() => {
+  const worker = new Worker(`${__dirname}/workers/render.cjs`);
+  console.log(`🟡 Launching render worker ${worker.threadId}`);
+  return worker;
+});
+const queue: {
+  svg: string;
+  resolve: (png: Buffer) => void;
+}[] = [];
+
+function manageQueue() {
+  if (queue.length > 0 && workers.length > 0) {
+    const { svg, resolve } = queue.shift()!;
+    const worker = workers.shift()!;
+
+    function cleanup() {
+      workers.push(worker);
+      manageQueue();
+    }
+
+    worker.postMessage(svg);
+    worker.on('message', (png: Uint8Array) => {
+      cleanup();
+      resolve(Buffer.from(png));
+    });
+    worker.on('error', (error) => {
+      cleanup();
+      throw error;
+    });
+  }
+}
+
+export function svgToPngThreaded(svg: string) {
+  return new Promise<Buffer>((resolve) => {
+    queue.push({ svg, resolve });
+    manageQueue();
+  });
+}