feat: add http gateway (#3)

packages/runner/src/setup/setup.ts

@@ -0,0 +1,71 @@
+import { join } from 'path';
+import os from 'os';
+import { nanoid } from 'nanoid';
+import { chmod, mkdir, rm, writeFile } from 'fs/promises';
+import { createServer } from 'net';
+import { EventEmitter } from 'eventemitter3';
+
+type SetupOptions = {
+  input?: Buffer | string;
+  script: string;
+  secrets?: Record<string, string>;
+};
+
+type RunEvents = {
+  message: (event: any) => void;
+  error: (error: Error) => void;
+  exit: () => void;
+};
+
+const setup = async (options: SetupOptions) => {
+  const { input, script, secrets } = options;
+  const emitter = new EventEmitter<RunEvents>();
+  const dataDir = join(os.tmpdir(), 'mini-loader', nanoid());
+
+  await mkdir(dataDir, { recursive: true });
+  await chmod(dataDir, 0o700);
+  const hostSocket = join(dataDir, 'host');
+  const httpGatewaySocket = join(dataDir, 'socket');
+  const server = createServer();
+  const inputLocation = join(dataDir, 'input');
+  const scriptLocation = join(dataDir, 'script.js');
+
+  if (input) {
+    await writeFile(inputLocation, input);
+  }
+  await writeFile(scriptLocation, script);
+  const env = {
+    HOST_SOCKET: hostSocket,
+    SECRETS: JSON.stringify(secrets || {}),
+    INPUT_PATH: inputLocation,
+    HTTP_GATEWAY_PATH: httpGatewaySocket,
+  };
+
+  const teardown = async () => {
+    server.close();
+    await rm(dataDir, { recursive: true, force: true });
+  };
+
+  server.on('connection', (socket) => {
+    socket.on('data', (data) => {
+      const message = JSON.parse(data.toString());
+      emitter.emit('message', message);
+    });
+  });
+
+  server.listen(hostSocket);
+
+  return {
+    env,
+    emitter,
+    teardown,
+    httpGatewaySocket,
+    scriptLocation,
+    hostSocket,
+  };
+};
+
+type Setup = Awaited<ReturnType<typeof setup>>;
+
+export type { Setup };
+export { setup };