This script is run as a Firebase function to notify in a Slack channel about changes to Firebase Remote config. Read more in the blogpost about it at andersos.net/2024/firebase-remote-config-slack-notifications

remoteConfigToSlack.ts

import * as admin from 'firebase-admin';
import * as functions from 'firebase-functions';
import { TemplateVersion } from 'firebase-functions/v1/remoteConfig';
import jsonDiff from 'json-diff';
import fetch from 'node-fetch';


// If you are unsure about how to generate webhooks for Slack read this https://api.slack.com/messaging/webhooks
// const test_feed = 'https://hooks.slack.com/services/...';
const slack_notification_channel = 'https://hooks.slack.com/services/...';


const remoteConfigToSlack = async (versionMetadata: TemplateVersion): Promise<boolean> => {

	functions.logger.log(`Remote config to Slack called`);
	const { app } = admin.instanceId();

	const currentVersion = versionMetadata.versionNumber;

	const current = await admin.remoteConfig().getTemplateAtVersion(currentVersion);
	const prev = await admin.remoteConfig().getTemplateAtVersion(currentVersion - 1);

	const diff = jsonDiff.diff(prev, current);
	const parameter = Object.keys(diff.parameters)[0] as string;
	const parameters = Object.values(diff.parameters)[0] as any;

	if(parameter.includes('__deleted')) {

		await fetch(slack_notification_channel, {
			method: 'POST',
			body: JSON.stringify(
				{
					'blocks': [
						{
							'type': 'section',
							'fields': [
								{
									'type': 'mrkdwn',
									'text': `*Firebase Remote Config Deleted (${app.options.projectId})*`
								}
							]
						},
						{
							'type': 'section',
							'fields': [
								{
									'type': 'mrkdwn',
									'text': `*Parameter deleted:*\n${parameter.substring(0, parameter.length - 9)}`
								}
							]
						}
					]
				}
			),
		});

	} else if(parameter.includes('__added')) {

		await fetch(slack_notification_channel, {
			method: 'POST',
			body: JSON.stringify(
				{
					'blocks': [
						{
							'type': 'section',
							'fields': [
								{
									'type': 'mrkdwn',
									'text': `*Firebase Remote Config Added (${app.options.projectId})*`
								}
							]
						},
						{
							'type': 'section',
							'fields': [
								{
									'type': 'mrkdwn',
									'text': `*Parameter added:*\n${parameter.substring(0, parameter.length - 7)}`
								}
							]
						}
					]
				}
			),
		});

	} else {

		await fetch(slack_notification_channel, {
			method: 'POST',
			body: JSON.stringify(
				{
					'blocks': [
						{
							'type': 'section',
							'fields': [
								{
									'type': 'mrkdwn',
									'text': `*Firebase Remote Config Change (${app.options.projectId})*`
								}
							]
						},
						{
							'type': 'section',
							'fields': [
								{
									'type': 'mrkdwn',
									'text': `*Parameter changed:*\n${parameter}`
								}
							]
						},
						{
							'type': 'section',
							'fields': [
								{
									'type': 'mrkdwn',
									'text': `*Old:*\n${parameters.defaultValue.value.__old}`
								},
								{
									'type': 'mrkdwn',
									'text': `*New:*\n${parameters.defaultValue.value.__new}`
								}
							]
						}
					]
				}
			),
		});

	}


	return true;

};

export default remoteConfigToSlack;