generator-firebase-functions

Yeoman generator for starting projects using Firebase Functions (tests optional). Includes function sub-generator.

Installation

Install Yeoman and generator-firebase-functions using npm (we assume you have pre-installed node.js):

npm install -g yo generator-firebase-functions

Getting Started

• Install dependencies: npm install (installs functions dependencies as well)

Functions Scripts

A number of npm scripts which are in functions/package.json are exposed as top level npm scripts with functions: prefix.

Building

Running in the root of the project:

npm run functions:build

In the functions folder:

npm run build

Serving Functions

Running in the root of the project:

npm run functions:serve

In the functions folder:

npm run serve

Emulation

Functions can be emulated through the functions shell. To run in the root of the project:

npm run functions:emulate

In the functions folder:

npm run emulate

Sub generators

Sub generators are included to help speed up the application building process. You can run a sub-generator by calling yo firebase-functions:<name of sub-generator> <param1>.

Example: To call the component sub-generator with "SomeThing" as the first parameter write: yo firebase-functions:function SomeThing

Path Argument

Another argument can be passed to sub generators (unless otherwise noted) to provide the base path in which you would like to run the generator (starts from src). For example: yo firebase-functions:function Car routes/Project runs the component generator within the Project route folder meaning that the component will be added to routes/Project/components instead of the top level src/components folder.

Function

Generates a Cloud Function allowing the user to specify trigger type (from HTTPS, Firestore, RTDB, Auth, or Storage)

A component is best for things that will be reused in multiple places. Our example

command

yo firebase-functions:function uppercaser

result

/functions
--/uppercaser
----index.js

For firebase-functions <v1.0.0:

/functions/uppercaser/index.js:

import * as functions from 'firebase-functions'
import * as admin from 'firebase-admin'
import { to } from 'utils/async'

/**
 * @name uppercaser
 * Cloud Function triggered by Real Time Database Event
 * @type {functions.CloudFunction}
 */
export default functions.database
  .ref('/users/{userId}')
  .onUpdate(uppercaserEvent)

/**
 * @param  {functions.Event} event - Function event
 * @return {Promise}
 */
async function uppercaserEvent(event) {
  const eventData = event.data.val()
  const params = event.params
  const ref = admin.database().ref('responses')
  const [writeErr, response] = await to(ref.push(eventData))
  if (writeErr) {
    console.error('Error writing response:', writeErr.message || writeErr)
    throw writeErr
  }
  return response
}

For firebase-functions >=v1.0.0:

/functions/uppercaser/index.js:

import * as functions from 'firebase-functions'
import * as admin from 'firebase-admin'
import { to } from 'utils/async'

/**
 * @name uppercaser
 * Cloud Function triggered by Real Time Database Event
 * @type {functions.CloudFunction}
 */
export default functions.database
  .ref('/users/{userId}')
  .onUpdate(uppercaserEvent)

/**
 * @param  {functions.Event} event - Function event
 * @return {Promise}
 */
async function uppercaserEvent(change, context) {
  // const { params, auth, timestamp } = context
  // const { before, after } = change
  const ref = admin.database().ref('responses')
  const [writeErr, response] = await to(ref.push({ hello: 'world' }))
  if (writeErr) {
    console.error('Error writing response:', writeErr.message || writeErr)
    throw writeErr
  }
  return response
}

Note: This sub-generator does not support the Path Argument (functions are already placed within a folder matching their name).