Firebase Auth

Triggers a function when a Firebase Auth user object changes.

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Code sample


using CloudNative.CloudEvents;
using Google.Cloud.Functions.Framework;
using Google.Events.Protobuf.Firebase.Auth.V1;
using Microsoft.Extensions.Logging;
using System.Threading;
using System.Threading.Tasks;

namespace FirebaseAuth
    public class Function : ICloudEventFunction<AuthEventData>
        private readonly ILogger _logger;

        public Function(ILogger<Function> logger) =>
            _logger = logger;

        public Task HandleAsync(CloudEvent cloudEvent, AuthEventData data, CancellationToken cancellationToken)
            _logger.LogInformation("Function triggered by change to user: {uid}", data.Uid);
            if (data.Metadata is UserMetadata metadata)
                _logger.LogInformation("User created at: {created:s}", metadata.CreateTime.ToDateTimeOffset());
            if (!string.IsNullOrEmpty(data.Email))
                _logger.LogInformation("Email: {email}", data.Email);

            // In this example, we don't need to perform any asynchronous operations, so the
            // method doesn't need to be declared async.
            return Task.CompletedTask;


// Package firebase contains a Firestore Cloud Function.
package firebase

import (

// AuthEvent is the payload of a Firestore Auth event.
type AuthEvent struct {
	Email    string `json:"email"`
	Metadata struct {
		CreatedAt time.Time `json:"createdAt"`
	} `json:"metadata"`
	UID string `json:"uid"`

// HelloAuth is triggered by Firestore Auth events.
func HelloAuth(ctx context.Context, e AuthEvent) error {
	log.Printf("Function triggered by creation or deletion of user: %q", e.UID)
	log.Printf("Created at: %v", e.Metadata.CreatedAt)
	if e.Email != "" {
		log.Printf("Email: %q", e.Email)
	return nil


import java.util.logging.Logger;

public class FirebaseAuth implements RawBackgroundFunction {
  private static final Logger logger = Logger.getLogger(FirebaseAuth.class.getName());

  // Use GSON ( to parse JSON content.
  private static final Gson gson = new Gson();

  public void accept(String json, Context context) {
    JsonObject body = gson.fromJson(json, JsonObject.class);

    if (body != null && body.has("uid")) {"Function triggered by change to user: " + body.get("uid").getAsString());

    if (body != null && body.has("metadata")) {
      JsonObject metadata = body.get("metadata").getAsJsonObject();"Created at: " + metadata.get("createdAt").getAsString());

    if (body != null && body.has("email")) {"Email: " + body.get("email").getAsString());


 * Triggered by a change to a Firebase Auth user object.
 * @param {!Object} event The Cloud Functions event.
exports.helloAuth = event => {
  try {
    console.log(`Function triggered by change to user: ${event.uid}`);
    console.log(`Created at: ${event.metadata.createdAt}`);

    if ( {
      console.log(`Email: ${}`);
  } catch (err) {


import json
def hello_auth(data, context):
    """ Triggered by creation or deletion of a Firebase Auth user object.
            data (dict): The event payload.
            context ( Metadata for the event.
    print('Function triggered by creation/deletion of user: %s' % data["uid"])
    print('Created at: %s' % data["metadata"]["createdAt"])

    if 'email' in data:
        print('Email: %s' % data["email"])


require "functions_framework"

# Triggered by creation or deletion of a Firebase Auth user object.
FunctionsFramework.cloud_event "hello_auth" do |event|
  # Event-triggered Ruby functions receive a CloudEvents::Event::V1 object.
  # See
  # The Firebase event payload can be obtained from the `data` field.
  payload = "Function triggered by creation/deletion of user: #{payload['uid']}" "Created at: #{payload['metadata']['createdAt']}" "Email: #{payload['email']}" if payload.key? "email"

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