docs(*): Document AngularFireFunctions and AngularFireMessaging

README.md

@@ -92,8 +92,10 @@ Firebase offers two cloud-based, client-accessible database solutions that suppo
 ### Universal
 - [Server-side Rendering with Universal](docs/server-side-rendering.md)
 
-### Deploy to Firebase Hosting
+### Functions
+- [Getting started with Callable Functions](docs/functions/functions.md)
 
+### Deploy to Firebase Hosting
 - [Deploying AngularFire to Firebase Hosting](docs/deploying-angularfire-to-firebase.md)
 
 ### Ionic

docs/functions/functions.md

@@ -0,0 +1,72 @@
+# AngularFireFunctions
+
+> The Cloud Functions for Firebase client SDKs let you call functions directly from a Firebase app. To call a function from your app in this way, write and deploy an HTTPS Callable function in Cloud Functions, and then add client logic to call the function from your app.
+
+### Import the `NgModule`
+
+Cloud Functions for AngularFire is contained in the `@angular/fire/functions` module namespace. Import the `AngularFireFunctionsModule` in your `NgModule`. This sets up the `AngularFireFunction` service for dependency injection.
+
+```ts
+import { BrowserModule } from '@angular/platform-browser';
+import { NgModule } from '@angular/core';
+import { AppComponent } from './app.component';
+import { AngularFireModule } from '@angular/fire';
+import { AngularFireFunctionsModule } from '@angular/fire/functions';
+import { environment } from '../environments/environment';
+
+@NgModule({
+  imports: [
+    BrowserModule,
+    AngularFireModule.initializeApp(environment.firebase),
+    AngularFireFunctionsModule
+  ],
+  declarations: [ AppComponent ],
+  bootstrap: [ AppComponent ]
+})
+export class AppModule {}
+```
+
+### Injecting the AngularFireFunctions service
+
+Once the `AngularFireFunctionsModule` is registered you can inject the `AngularFireFunctions` service.
+
+```ts
+import { Component } from '@angular/core';
+import { AngularFireFunctions } from '@angular/fire/functions';
+
+@Component({
+  selector: 'app-component',
+  template: ``
+})
+export class AppComponent {
+  constructor(private fns: AngularFireFunctions { }
+}
+```
+
+### Creating a callable function
+
+AngularFireFunctions is super easy. You create a function on the server side and then "call" it by its name with the client library. 
+
+| method   |                    |
+| ---------|--------------------|
+| `httpCallable(name: string): (data: T) ` | Creates a callable function based on a function name. Returns a function that can create the observable of the http call. |
+```ts
+
+import { Component } from '@angular/core';
+import { AngularFireStorage } from '@angular/fire/functions';
+
+@Component({
+  selector: 'app-root',
+  template: `
+  { data$ } | async
+  `
+})
+export class AppComponent {
+  constructor(private fns: AngularFireFunctions) { 
+    const callable = fns.httpsCallable('my-fn-name');
+    this.data$ = callable({ name: 'some-data' });
+  }
+}
+```
+
+Notice that calling `httpsCallable()` does not initiate the request. It creates a reusable function that is called to initiate the request.