Init. Map does not function and only working on backend at the moment.

node_modules/engine.io-parser/build/esm/encodePacket.js

@@ -0,0 +1,33 @@
+import { PACKET_TYPES } from "./commons.js";
+export const encodePacket = ({ type, data }, supportsBinary, callback) => {
+    if (data instanceof ArrayBuffer || ArrayBuffer.isView(data)) {
+        return callback(supportsBinary ? data : "b" + toBuffer(data, true).toString("base64"));
+    }
+    // plain string
+    return callback(PACKET_TYPES[type] + (data || ""));
+};
+const toBuffer = (data, forceBufferConversion) => {
+    if (Buffer.isBuffer(data) ||
+        (data instanceof Uint8Array && !forceBufferConversion)) {
+        return data;
+    }
+    else if (data instanceof ArrayBuffer) {
+        return Buffer.from(data);
+    }
+    else {
+        return Buffer.from(data.buffer, data.byteOffset, data.byteLength);
+    }
+};
+let TEXT_ENCODER;
+export function encodePacketToBinary(packet, callback) {
+    if (packet.data instanceof ArrayBuffer || ArrayBuffer.isView(packet.data)) {
+        return callback(toBuffer(packet.data, false));
+    }
+    encodePacket(packet, true, (encoded) => {
+        if (!TEXT_ENCODER) {
+            // lazily created for compatibility with Node.js 10
+            TEXT_ENCODER = new TextEncoder();
+        }
+        callback(TEXT_ENCODER.encode(encoded));
+    });
+}