docs: fix typos and clarify documentation (#2334)

Closes #2176. Closes #2156. Closes #2248. Closes #2264.

Author: Splaktar

README.md

@@ -1,5 +1,5 @@
 # AngularFire
-The official Angular library for Firebase
+The official [Angular](https://angular.io/) library for [Firebase](https://firebase.google.com/).
 
 ```bash
 ng add @angular/fire@next

docs/ionic/authentication.md

@@ -10,7 +10,7 @@ ionic cordova plugin add cordova-plugin-customurlscheme
 
 # Step 2: Add Firebase to your Ionic
 
- **Install firebase to angular project**
+ **Install Firebase to Angular project**
 
 Follow [this tutorial](https://github.com/angular/angularfire2/blob/master/docs/install-and-setup.md) to make a basic setup for your Ionic project.
 
@@ -19,7 +19,9 @@ Follow [this tutorial](https://github.com/angular/angularfire2/blob/master/docs/
 Go to [Firebase console](https://console.firebase.google.com/) then click **Add Firebase to your Android app** and follow the setup steps.
 
 
-# Step 3: Set up Firebase Authentication for Cordova ( summary from [firebase instruction](https://firebase.google.com/docs/auth/web/cordova))
+# Step 3: Set up Firebase Authentication for Cordova
+
+*This is a summary from the [Firebase instructions](https://firebase.google.com/docs/auth/web/cordova).*
 
  **Setup Dynamic Link**
  In the Firebase console, open the **Dynamic Links** section at bottom left panel, setup by their instruction
@@ -39,11 +41,11 @@ Go to [Firebase console](https://console.firebase.google.com/) then click **Add
     <preference name="AndroidLaunchMode" value="singleTask" />
 ```
 
-  *Make sure your `<widget id="com.yourandroid.id" ... >` the same with android app's id you 
-  added in firebase*
+  *Make sure your `<widget id="com.yourandroid.id" ... >` the same with Android app's id you 
+  added in Firebase.*
 
-# Step 4: Add login code:
-at `login.service.ts` add this function: 
+# Step 4: Add login code
+In `login.service.ts` add this function: 
 ```ts
 
 import { AngularFireAuth } from '@angular/fire/auth';
@@ -59,12 +61,12 @@ export class AuthService {
 	}
 
   signInWithFacebook() {
-		console.log('Sign in with google');
+		console.log('Sign in with Facebook');
 		return this.oauthSignIn(new firebase.auth.FacebookAuthProvider());
 	}
 
   signInWithGoogle() {
-		console.log('Sign in with google');
+		console.log('Sign in with Google');
 		return this.oauthSignIn(new firebase.auth.GoogleAuthProvider());
 	}
 
@@ -75,8 +77,7 @@ export class AuthService {
 			return this.afAuth.auth.signInWithRedirect(provider)
 			.then(() => {
 				return this.afAuth.auth.getRedirectResult().then( result => {
-					// This gives you a Google Access Token.
-					// You can use it to access the Google API.
+					// This gives you an Access Token. You can use it to access the associated APIs.
 					let token = result.credential.accessToken;
 					// The signed-in user info.
 					let user = result.user;
@@ -93,9 +94,11 @@ export class AuthService {
 
 # Common problems
 
-If you got error when build code like this:
-`UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: Cannot read property 'manifest' of undefined`
+If you get an error, when you build the code, that looks like this:
+```
+UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: Cannot read property 'manifest' of undefined
+```
 
-Please, using this fix from [issue](https://github.com/nordnet/cordova-universal-links-plugin/issues/134):
+Please take a look at the fix from [this issue](https://github.com/nordnet/cordova-universal-links-plugin/issues/134):
 > Making this change in 'cordova-universal-links-plugin/hooks/lib/android/manifestWriter.js' fixed this issue for me:
 > [b2c5784#diff-d5955d9f4d88b42e5efd7a3385be79e9](https://github.com/nordnet/cordova-universal-links-plugin/commit/b2c5784764225319648e26aa5d3f42ede6d1b289#diff-d5955d9f4d88b42e5efd7a3385be79e9)

docs/messaging/messaging.md

@@ -4,11 +4,16 @@
 
 ### AngularFireMessaging is not compatible with the Angular Service Worker
 
-If you are using the Angular Service Worker, you are not currently able to use AngularFireMessaging. If you'd like this feature please file an issue in [either repository](https://github.com/angular/angular/tree/master/packages/service-worker). Your alternatives are to use [WorkboxJS](https://developers.google.com/web/tools/workbox/) or just simply use the Firebase Messaging Service Worker, which is detailed below.
+If you are using the Angular Service Worker, you are not currently able to use AngularFireMessaging.
+If you'd like this feature please add your 👍 to [this issue](https://github.com/angular/angular/issues/34352).
+
+Your alternatives are to use
+- [WorkboxJS](https://developers.google.com/web/tools/workbox/)
+- The Firebase Messaging Service Worker, which is detailed below
 
 ### Import the `NgModule`
 
-Push Notifications for AngularFire is contained in the `@angular/fire/messaging` module namespace. Import the `AngularFireMessagingModule` in your `NgModule`. This sets up the `AngularFireMessaging` service for dependency injection.
+Push Notifications for AngularFire are contained in the `@angular/fire/messaging` module namespace. Import the `AngularFireMessagingModule` in your `NgModule`. This sets up the `AngularFireMessaging` service for dependency injection.
 
 ```ts
 import { BrowserModule } from '@angular/platform-browser';
@@ -32,9 +37,9 @@ export class AppModule {}
 
 ### Setting up the Firebase Messaging Service Worker
 
-There are two parts Firebase Messaging, a Service Worker and the DOM API. AngularFireMessaging allows you to request permission, get tokens, delete tokens, and subscribe to messages on the DOM side. To register to receive notifications you need to set up the Service Worker. [The official Firebase documentation for setting up the details exactly how to do that](https://firebase.google.com/docs/cloud-messaging/js/client). 
+There are two parts to Firebase Messaging, a Service Worker and the DOM API. AngularFireMessaging allows you to request permission, get tokens, delete tokens, and subscribe to messages on the DOM side. To register to receive notifications you need to set up the Service Worker. [The official Firebase documentation for setting up the details exactly how to do that](https://firebase.google.com/docs/cloud-messaging/js/client). 
 
-You can either use the `firebase-messaging-sw.js` file provided in the docs or you can set your own Service Worker to import that script. Make sure to set up your `.angular-cli.json` file to copy over the Service Worker file:
+You can either use the `firebase-messaging-sw.js` file provided in the docs or you can set your own Service Worker to import that script. Make sure to set up your `angular.json` file to copy over the Service Worker file:
 
 ```json
   "assets": [
@@ -47,7 +52,7 @@ You can either use the `firebase-messaging-sw.js` file provided in the docs or y
 
 ### Requesting permission
 
-Once you have the Firebase Messaging Service Worker setup and installed, you need to request permission to send a user notifications. While the browser will popup a UI for you, it is highly recommend to ask the user for permission with a custom UI and only ask when it makes sense. If you blindly ask for permission you have an extremely high chance of getting denied.
+Once you have the Firebase Messaging Service Worker set up and installed, you need to request permission to send a user notifications. While the browser will popup a UI for you, it is highly recommend to ask the user for permission with a custom UI and only ask when it makes sense. If you blindly ask for permission, you have an extremely high chance of getting denied or blocked.
 
 ```ts
 import { Component } from '@angular/core';
@@ -57,7 +62,7 @@ import { AngularFireMessaging } from '@angular/fire/messaging';
   selector: 'app-root',
   template: `
   <button (click)="requestPermission()">
-    Hey this is a chat app, you should let us send you notifications for these reasons!
+    Hello this is a chat app. You should let us send you notifications for this reason.
   </button>
   `
 })
@@ -84,7 +89,7 @@ import { mergeMapTo } from 'rxjs/operators';
   selector: 'app-root',
   template: `
   <button (click)="requestPermission()">
-    Hey this is a chat app, you should let us send you notifications for these reasons!
+    Hello this is a chat app. You should let us send you notifications for this reason.
   </button>
   `
 })
@@ -101,7 +106,7 @@ export class AppComponent {
 }
 ```
 
-Once you have a user's token, you need to save it to the server in order to send them notifications in response to events. Let's say ou want to send a push each time a user sends a chat message. Once a user grants permission, you can send the token to the Realtime Database or Cloud Firestore and associate it with a unique id, like a Firebase Auth UID. You can then create a Cloud Function trigger that looks up the user's token when a chat message is created.
+Once you have a user's token, you need to save it to the server in order to send them notifications in response to events. Let's say you want to send a push each time a user sends a chat message. Once a user grants permission, you can send the token to the Realtime Database or Cloud Firestore and associate it with a unique id, like a Firebase Auth UID. You can then create a Cloud Function trigger that looks up the user's token when a chat message is created.
 
 ### Shortcutting token requests
 
@@ -115,7 +120,7 @@ import { AngularFireMessaging } from '@angular/fire/messaging';
   selector: 'app-root',
   template: `
   <button (click)="requestPermission()">
-    Hey this is a chat app, you should let us send you notifications for these reasons!
+    Hello this is a chat app. You should let us send you notifications for this reason.
   </button>
   `
 })
@@ -146,7 +151,7 @@ import { mergeMap } from 'rxjs/operators';
   selector: 'app-root',
   template: `
   <button (click)="deleteMyToken()">
-    Delete my token plz
+    Delete my token
   </button>
   `
 })
@@ -156,7 +161,7 @@ export class AppComponent {
     this.afMessaging.getToken
       .pipe(mergeMap(token => this.afMessaging.deleteToken(token)))
       .subscribe(
-        (token) => { console.log('Deleted!'); },
+        (token) => { console.log('Token deleted!'); },
       );
   }
 }

docs/remote-config/getting-started.md

@@ -46,7 +46,7 @@ budget: <T>(interval: number) => MonoTypeOperatorFunction<T>
 // scanToObject is for use with .changes
 scanToObject: () => OperatorFunction<Parameter, {[key: string]: string|undefined}>
 
-// mapToObject is the same behavior are scanToObject but for use with .parameters,
+// mapToObject is the same behavior as scanToObject but for use with .parameters
 mapToObject: () => OperatorFunction<Parameter[], {[key: string]: string|undefined}>
 
 SETTINGS = InjectionToken<remoteConfig.Settings>;
@@ -61,9 +61,9 @@ Using the `SETTINGS` DI Token (*default: {}*) will allow you to [configure Fireb
 
 ### Configure default values with  `DEFAULTS`
 
-Providing `DEFAULTS ({[key: string]: string | number | boolean})` has `AngularFireRemoteConfig` emit the provided defaults first, which allows you to count on Remote Config when the user is offline or in environments that the Remote Config service does not handle (i.e, Server Side Rendering).
+Providing `DEFAULTS ({[key: string]: string | number | boolean})` tells `AngularFireRemoteConfig` to emit the provided defaults first. This allows you to count on Remote Config when the user is offline or in environments that the Remote Config service does not handle (i.e. Server Side Rendering).
 
-## Putting it all together:
+## Putting it all together
 
 ```ts
 @NgModule({
@@ -106,23 +106,25 @@ constructor(remoteConfig: AngularFireRemoteConfig) {
   remoteConfig.booleans.enableAwesome.subscribe(...); // boolean
   remoteConfig.numbers.titleBackgroundColor.subscribe(...); // number
 
-  // however those may emit more than once as the remote config cache fires and gets fresh values from the server
-  // you can filter it out of .changes for more control:
+  // however those may emit more than once as the remote config cache fires and gets fresh values
+  // from the server. You can filter it out of .changes for more control:
   remoteConfig.changes.pipe(
     filter(param => param.key === 'titleBackgroundColor'),
     map(param => param.asString())
     // budget at most 800ms and return the freshest value possible in that time
-    // our budget pipe is similar to timeout but won't error or abort the pending server fetch (it won't emit it, if the deadline is exceeded, but it will have been fetched so can use the freshest values on next subscription)
+    // our budget pipe is similar to timeout but won't error or abort the pending server fetch
+    // (it won't emit it, if the deadline is exceeded, but it will have been fetched so can use the
+    // freshest values on next subscription)
     budget(800),
     last()
   ).subscribe(...)
 
-  // just like .changes, but scanned as into an array
+  // just like .changes, but scanned into an array
   remoteConfig.parameters.subscribe(all => ...);
 
   // or make promisified firebase().remoteConfig() calls direct off AngularFireRemoteConfig
   // using our proxy
   remoteConfig.getAll().then(all => ...);
   remoteConfig.lastFetchStatus.then(status => ...);
 }
-```
+```

docs/rtdb/querying-lists.md

@@ -81,7 +81,7 @@ size$.next('small');
 import { Component } from '@angular/core';
 import { AngularFireDatabase, AngularFireAction } from '@angular/fire/database';
 import { Observable, Subscription, BehaviorSubject } from 'rxjs';
-import { switchMap } 'rxjs/operators';
+import { switchMap } from 'rxjs/operators';
 import 'firebase/database';
 
 @Component({