Firestore Metrics

This is a library which uses the Cloud Monitoring API v3 to view Firestore usage metrics.

Pre-requisites

1. A service account with permission to access the API.
   1. Viewer role should suffice.
2. Project must be billing enabled.
   1. This might be more of a bug as requests that use the bearer token obtained from a service account results in a 403 error when the project is not billing enabled.

How to use

1. Create a service account.
   1. Follow steps here to create a service account.
   2. Select the Console tab.
   3. When selecting a role, under Quick access > Basic, pick Viewer.
2. Download the service account keys.
   1. Follow the steps here to download the service account key.
3. Pass the service-account key file path or service-account credentials to FirestoreMetrics

Method references

Usage metrics

• getRequestCount() - Get Firestore API calls count
• getReadCount() - Get Firestore read count metrics
• getWriteCount() - Get Firestore write count metrics
• getDeleteCount() - Get Firestore delete count metrics
• getSnapshotListeners() - Get Firestore snapshot listeners count metrics
• getActiveConnections() - Get Firestore active connections count metrics
• getTTLDeletionCount() - Get Firestore documents deleted by TTL services count
• getRulesEvaluationCount() - Get Firestore Security Rule evaluations count performed in response to write read requests

Misc.

• getProjectId() - Gets the project ID and sets its value if it is still null
• generateToken() - Generate an access token to be used to authenticate requests
• setAccessToken() - Overwrites the access token used to authenticate requests

Get read metrics

import { FirestoreMetrics } from "firestore-metrics";

async function testApi() {
  const firestoreMetrics = new FirestoreMetrics({
    serviceAccountPath: "./service-account.json",
  });
  const readUsage = await firestoreMetrics.getReadCount(
    "2023-07-22T08:00:00Z",
    "2023-07-22T22:42:15Z"
  );

  console.log(JSON.stringify(readUsage, null, 4));
}

testApi();

Output would look like:

[
  {
    "type": "QUERY",
    "interval": {
      "startTime": "2023-08-21T16:15:00Z",
      "endTime": "2023-08-21T16:16:00Z"
    },
    "count": 26
  },
  {
    "type": "QUERY",
    "interval": {
      "startTime": "2023-08-21T16:14:00Z",
      "endTime": "2023-08-21T16:15:00Z"
    },
    "count": 15
  },
  {
    "type": "QUERY",
    "interval": {
      "startTime": "2023-08-21T15:51:00Z",
      "endTime": "2023-08-21T15:52:00Z"
    },
    "count": 11
  }
]

Get write metrics

import { FirestoreMetrics } from "firestore-metrics";

async function testApi() {
  const firestoreMetrics = new FirestoreMetrics({
    serviceAccountPath: "./service-account.json",
  });
  const writeUsage = await firestoreMetrics.getWriteCount(
    "2023-08-21T15:00:00Z",
    "2023-08-21T20:00:00Z"
  );

  console.log(JSON.stringify(writeUsage, null, 4));
}

testApi();

Output would look like:

[
  {
    "op": "CREATE",
    "interval": {
      "startTime": "2023-08-21T16:09:00Z",
      "endTime": "2023-08-21T16:10:00Z"
    },
    "count": 1
  },
  {
    "op": "UPDATE",
    "interval": {
      "startTime": "2023-08-21T16:15:00Z",
      "endTime": "2023-08-21T16:16:00Z"
    },
    "count": 1
  },
  {
    "op": "UPDATE",
    "interval": {
      "startTime": "2023-08-21T16:09:00Z",
      "endTime": "2023-08-21T16:10:00Z"
    },
    "count": 1
  }
]

Ways to authenticate request

Using a service-account file

Just provide the path to your service-account file

const firestoreMetrics = new FirestoreMetrics({
  serviceAccountPath: "./service-account.json",
});

Using service-account credentials

Just provide the JSON object of your service-account credentials

const firestoreMetrics = new FirestoreMetrics({
  credentials: {
    type: "service_account",
    project_id: "<PROJECT_ID>",
    private_key_id: "<PRIVATE_KEY_ID>",
    private_key: "<PRIVATE_KEY>",
    client_email: "<CLIENT_EMAIL>",
    client_id: "<CLIENT_ID>",
    auth_uri: "<AUTH_URI>",
    token_uri: "<TOKEN_URI>",
    auth_provider_x509_cert_url: "<AUTH_PROVIDER_X509_CERT_URL>",
    client_x509_cert_url: "<CLIENT_X509_CERT_URL>",
    universe_domain: "<UNIVERSE_DOMAIN>",
  },
});