Simple node server for my Intercom Messenger app. Run with `node index.js`

index.js

const HTTP = require('http');

const INITIALIZE_RESPONSE = {
  "canvas": {
    "content": {
      "components": [
        {
          "type": "text",
          "text": "Tell us what your favourite product is!",
        },
        {
          "type": "input",
          "id": "favouriteProduct",
          "placeholder": "Enter your favourite product",
          "action": {
            "type": "submit",
          },
        },
      ],
    },
  },
};

function collectRequestBody(request, callback) {
  let body = '';
  request.on('data', chunk => {
    body += chunk.toString();
  });
  request.on('end', () => {
    callback(JSON.parse(body));
  });
}

HTTP.createServer((request, response) => {
  response.setHeader('Content-Type', 'application/json');
  if (request.url === '/initialize/') {
    response.end(JSON.stringify(INITIALIZE_RESPONSE));
  } else if (request.url === '/submit/') {
    collectRequestBody(request, (requestBody) => {
      response.end(JSON.stringify({
        "canvas": {
          "content": {
            "components": [
              {
                "type": "text",
                "text": `You said "${requestBody.input_values.favouriteProduct}" was your favourite. Thanks!`,
              },
            ],
          },
        },
      }));
    });
  } else {
    response.statusCode = 404;
    response.end();
  }
}).listen(3000, (error) => {
  if (error) {
    console.log("Something went wrong", error);
    return;
  }
  console.log("Server listening on port 3000");
});