Functions

@nativescript/firebase-functions #

Contents #

• Intro
• Set up your app for Firebase
• Add the Firebase Functions SDK to your app
• Use @nativescript/firebase-functions
  • Calling an endpoint
  • Set and access regional Cloud Functions endpoints
    • Set regional function endpoint
    • Access regional function endpoint
  • Test Cloud Functions with a local emulator
• API
  • Functions class
    • ios
    • android
    • app
    • constructor()
    • httpsCallable()
    • useEmulator()

Intro #

This plugin allows you to use Firebase Cloud Functions with NativeScript.

Set up your app for Firebase #

• To set up and initialize Firebase for your NativeScript app, follow the instructions on the documentation of the @nativescript/firebase-core plugin.

Add the Firebase Functions SDK to your app #

To add the Cloud Firebase Functions SDK to your app, install the @nativescript/firebase-functions plugin by running the following command in the root directory of your project.

npm install @nativescript/firebase-functions

Use @nativescript/firebase-functions #

The Cloud Functions module provides the functionality to directly trigger deployed HTTPS callable functions, without worrying about security or implementing an HTTP request library.

Functions deployed to Firebase have unique names, allowing you to easily identify which endpoint you wish to send a request to.

Calling an endpoint #

Assuming we have to deploy a callable endpoint named listProducts. To call the endpoint, the library exposes a httpsCallable method. For example:

// Deployed HTTPS callable
exports.listProducts = functions.https.onCall(() => {
  return [
    /* ... */
    // Return some data
  ]
})

Within the application, the list of products returned can be directly accessed by passing the name of the endpoint to the httpsCallable method:

import { firebase } from '@nativescript/firebase-core'
import '@nativescript/firebase-functions'
firebase()
  .functions()
  .httpsCallable('listProducts')()
  .then(response => {
    setProducts(response.data)
    setLoading(false)
  })

Set and access regional Cloud Functions endpoints #

Cloud Functions are regional, which means the infrastructure that runs your Cloud Function is located in specific regions.

By default, functions run in the us-central1 region. To see supported regions, see supported regions.

Set regional function endpoint #

To run functions in a different region after initializing Firebase App, set the region using firebase().app().functions(region).

The code below shows an example of setting a regional function endpoint(europe-west2):

// Deployed HTTPS callable
exports.listProducts = functions.region('europe-west2').https.onCall(() => {
  return [
    /* ... */
    // Return some data
  ]
})

Access regional function endpoint #

To access a regional function endpoint, call the firebase().app().functions(region) method on the Firebase App instance:

import { firebase } from '@nativescript/firebase-core'
import '@nativescript/firebase-functions'

firebase().initializeApp()
firebase().app().functions('europe-west2')

firebase()
  .functions()
  .httpsCallable('listProducts')()
  .then(response => {
    setProducts(response.data)
    setLoading(false)
  })

Test Cloud Functions with a local emulator #

Whilst developing your application with Cloud Functions, you can run the functions inside of a local emulator.

To call the emulated functions, connect the Cloud Functions to a local emulator by calling the useEmulator method on the Functions instance with the host and port of the emulator.

import { firebase } from '@nativescript/firebase-core'
firebase().functions().useEmulator('localhost', 5000)

API #

Functions class #

ios #

functionsIOs: FIRFunctions = firebase.functions().ios

A readonly property that returns the native iOS FIRFunctions instance.

android #

functionsAndroid: com.google.firebase.functions.FirebaseFunctions =
  firebase.functions().android

A readonly property that returns the native Android com.google.firebase.functions.FirebaseFunctions instance.

app #

app: FirebaseApp = firebase().functions().app

A readonly property that returns the FirebaseApp instance associated with the Functions instance.

constructor() #

functions: Functions = new Functions(app)

Creates a new Functions instance.

httpsCallable() #

task: HttpsCallable = firebase().functions().httpsCallable(name, options)

httpsCallable(data)
  .then((response: HttpsCallableResult) => {
    // Do something with the response
  })
  .catch((error: HttpsCallableError) => {
    console.log(error.code, error.message, error.details)
  })

Returns a task function that can be called with optional data. The task function returns a Promise that will be resolved with the result(HttpsCallableResult) of the function execution. If the task fails, the Promise will be rejected with an HttpsCallableError.

useEmulator() #

firebase().functions().useEmulator(host, port)

Allows you to test Cloud Functions locally by connecting to the emulator.

License #

Apache License Version 2.0