Why can't I access the body or properties of this POST request sent to a HTTP Firebase Cloud Function?

Question

I'm sending a POST request to a HTTP Firebase Cloud Function endpoint which contains the following body:

{
  "securityContext": "edbsne0f17660e9ab49ad9bc3ddd4656230e0a9304bd15916f595b793da9109e1f7aa61e76c4afa91319011a7259b24ed583302334e22c5544c4e00506cf2fed93b28434e4088b22dda02712adf63bb6a370f",
  "event": "onInstall",
  "orgId": "7001935574",
  "dc": "AU"
}

But when I try to access any of those properties it shows undefined . The entire body is also undefined .

This is what my onRequest HTTP Cloud Function endpoint looks like. It also shows my other failed attempts of getting the body data, which I have commented out:

export const getZohoDeskCallBack = functions.https.onRequest((req, res) => {

  const body = req.body;
  functions.logger.info('body', body);

  const rawBody = req.body;
  functions.logger.info('rawBody', rawBody);

  // Other attempt 1:
  // const bodySecurityContext = req.body.securityContext;
  // functions.logger.info('bodySecurityContext', bodySecurityContext);

  // Other attempt 2:
  // const rawBodySecurityContext = req.rawBody.securityContext;
  // functions.logger.info('rawBodySecurityContext', rawBodySecurityContext);

  // Other attempt 3:
  // const reqBodyToJSON = req.body.toJSON();
  // functions.logger.info('req.body.toJSON()', reqBodyToJSON);

  // Other attempt 4:
  // const reqRawBodyToJSON = req.rawBody.toJSON();
  // functions.logger.info('req.rawBody.toJSON()', reqRawBodyToJSON);

  // Other attempt 5:
  // const reqBodyToJSONparse = JSON.parse(req.body);
  // functions.logger.info('reqBodyToJSONparse', reqBodyToJSONparse);

  // Other attempt 6:
  // const reqRawBodyToJSONparse = JSON.parse(req.rawBody);
  // functions.logger.info('reqRawBodyToJSONparse', reqRawBodyToJSONparse);

  // Other attempt 7:
  // const reqBodyToJSONparse = req.body.toString();
  // functions.logger.info('reqBodyToJSONparse', reqBodyToJSONparse);

  // Other attempt 8:
  // const reqRawBodyToJSONparse = req.rawBody.toString();
  // functions.logger.info('reqRawBodyToJSONparse', reqRawBodyToJSONparse);

  // Other attempt 9:
  // const reqBodyToJSONparse = req.body.toString();
  // const securityContext = reqBodyToJSONparse.securityContext;
  // functions.logger.info('securityContext', securityContext);

  res.end();
});

You can see a test of the POST request here and here .

Apparently, if a request has a content-type of application/json Firebase Cloud Functions will automatically parse the JSON and put it into the body property.

But as you can see from those tests linked above the header content-type is empty or missing. Also I am unable to change the POST request because I have no control over that.

Maybe that could be the issue? If so, I thought I could access it from the rawBody property, but that also doesn't work.

I have been pulling my hair out trying to solve this. Any help would be much appreciated.

Answer 1

Apparently, if a request has a content-type of application/json Firebase Cloud Functions will automatically parse the JSON and put it into the body property.

That's because you do need to add the Content-Type header and Firebase use the appropriate parser for that request. For more information on the libraries that Firebase uses, checkout the documentation .

You can use the body parser middleware and force parse the body as JSON as shown below:

import * as functions from "firebase-functions/v1";
import * as express from "express";
import * as bodyParser from "body-parser";

const app = express();

const parseJsonMiddleware = bodyParser.json({
  type(req) {
    return true;
  },
});

app.post("/getZohoDeskCallBack", parseJsonMiddleware, (req, res) => {
  const body = req.body;
  console.log("body", body);

  const rawBody = req.body;
  console.log("rawBody", rawBody);

  res.end();
});

export const api = functions.https.onRequest(app);

You'll have to update your webhook URL as this will add /api in the URL like this:

POST https://[FUNCTIONS_URL]/api/getZohoDeskCallBack