Getting Cold start latency of 5+ seconds even after using the preferRest option for firebase-admin

[HarshitPersona]

Thanks for stopping by to let us know something could be better!

Linked issues- https://issuetracker.google.com/issues/158014637 and firebase/firebase-admin-node#1901

Environment details

• OS: macOS Ventura
• Node.js version: 18
• npm version: 9.5.1
• @google-cloud/firestore version: 6.5.0

Thanks!

[ehsannas]

Hey @HarshitPersona , can you provide more information about your environment? Are you sending the requests from your local machine (macOS)?

[HarshitPersona]

I have written a cloud function in GCP in Nodejs18 environment which is connecting to the firestore database through firebase-admin library. See below for the code snippet-

let isAlreadyInitialized = false;
let db;

const middleware = async (req, res) => {
  try {
    const apiKey = req.headers["x-api-key"];
    if (!apiKey)
      return res.status(401).send({ message: "A valid API Key is required!" });

    const { initializeApp } = require("firebase-admin/app");
    const {
      initializeFirestore,
      getFirestore,
    } = require("firebase-admin/firestore");

    if (!isAlreadyInitialized) {
      const app = initializeApp();
      initializeFirestore(app, { preferRest: true });
      db = getFirestore(app);
      isAlreadyInitialized = true;
    }

    const query = db.collection("apps").where("apiKey", "==", apiKey);

    const querySnapshot = await query.get();
      return res.send({ tests: "This is a test response!" });
  } catch (e) {
    return res.status(500).send(e);
  }
};

exports.fetchCreative = middleware;

If you notice here - return res.send({ tests: "This is a test response!" }); I have send back a test response but this response is taking 5+ seconds on cold starts even though I used preferRest option as you can see in the above code.

[HarshitPersona]

"firebase-admin": "^11.8.0" - this is my dependency

[ehsannas]

Thanks for reporting @HarshitPersona .

Would you be able to answer these questions that'll help us understand what's going on?

1- How are you measuring the latency/delay? It's conceivable that a part (or majority) of what you have measured is in network latency for the response, not the time it took to update the database.

2- What would your measurement be if you set preferRest to false?

3- What would your measurement be if you don't interact with Firestore? Meaning, your cloud function just does initializeApp(); and then return res.send({ tests: "This is a test response!" });?

[ehsannas]

Closing since there's been no response in 3 weeks. Feel free to comment if the above information comes to light.