Question
What is the best way to prevent users from using an email address that does not end in @mycompany.com from logging in to our internal app through Firebase/Google auth?
Goal
- Prevent users from using the wrong email to login to the app
- Fetch the user's company email address and use that for authentication elsewhere (i.e. for pulling data from an internal website)
Restraints
- I am using react-native init because I had to implement with our company's native SDK module
- Preferably would like a solution with Firebase since we are already using it with said native SDK module for FCM/push notifications.
Research results
- I saw that react-native-google-signin had a "hostedDomain" option, but it doesn't seem to do anything. I'm not sure how to use it, and there are no docs or good examples of its use. There was a feature request for it here but that's all I can find.
- I saw that there is a similar repo, react-native-google-sign-in, but it doesn't offer any more information on this subject.
- I read somewhere that I'm probably thinking about this all wrong and authentication can't restrict email addresses(?), but I can restrict who can access information with said email addresses. This doesn't help me because we're not using Firebase's database for anything right now. I need a way to guide users to log in using their company email.
- This person seemed to have a similar issue and found a solution for passport, but I don't know how to apply this to my use case.
Setup
- IntelliJ Ultimate 2017.2.2
- React Native 0.47.1 (using react-native init, not CRNA or expo since I needed to integrate with a native SDK module)
- google-services.json from Firebase exists in android/app folder
Android Setup
package.json dependencies
"dependencies": {
"create-react-class": "^15.6.0", /* Ignore this */
"firebase": "^4.2.0",
"react": "16.0.0-alpha.12",
"react-native": "0.47.1",
"react-native-app-intro": "^1.1.5",
"react-native-google-signin": "^0.11.0",
"react-native-linear-gradient": "^2.2.0",
"react-navigation": "^1.0.0-beta.12"
}
android/settings.gradle
rootProject.name = '[My Project Name]'
include ':react-native-google-signin'
project(':react-native-google-signin').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-google-signin/android')
include ':react-native-linear-gradient'
project(':react-native-linear-gradient').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-linear-gradient/android')
include ':app', ':[Internal Android SDK]'
android/build.gradle
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:2.3.3'
classpath 'com.google.gms:google-services:3.0.0'
}
}
allprojects {
repositories {
mavenLocal()
jcenter()
maven {
// All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
url "$rootDir/../node_modules/react-native/android"
}
}
}
ext {
compileSdkVersion = 26
buildToolsVersion = "26.0.1"
}
subprojects { subproject ->
afterEvaluate{
if((subproject.plugins.hasPlugin('android') || subproject.plugins.hasPlugin('android-library'))) {
android {
compileSdkVersion rootProject.ext.compileSdkVersion
buildToolsVersion rootProject.ext.buildToolsVersion
}
}
}
}
android/app/build.gradle
apply plugin: "com.android.application"
[...]
dependencies {
compile(project(":react-native-google-signin")){
exclude group: "com.google.android.gms" // very important
}
compile project(':react-native-linear-gradient')
compile project(':[Internal Android SDK]')
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:appcompat-v7:26.0.0-alpha1'
compile 'com.facebook.react:react-native:+'
compile 'com.facebook.fresco:animated-gif:1.0.1'
compile 'com.google.android.gms:play-services-auth:10.0.1'
compile 'com.google.firebase:firebase-messaging:10.0.1'
}
[...]
apply plugin: 'com.google.gms.google-services'
React Native setup
Current folder structure:
> app
> components [...]
> config [...]
> screens
HomeScreen.js
LoginScreen.js
[...]
> styles [...]
router.js (just a simple StackNavigator setup from react-navigation)
> assets
> fonts [...]
> img [...]
> node_modules [...]
index.android.js
index.ios.js
package.json
[...]
LoginScreen.js (This is a work in progress)
import React, { Component } from 'react';
import { Alert, Button, Image, Text, View } from 'react-native';
import {GoogleSignin, GoogleSigninButton} from 'react-native-google-signin';
export default class LoginScreen extends Component{
constructor(props){
super(props);
this.state = {
user: null
}
}
componentDidMount() {
this._setupGoogleSignin().then(() => console.log('Mounted & Google setup complete.'));
}
async _setupGoogleSignin() {
try {
await GoogleSignin.hasPlayServices({ autoResolve: true });
await GoogleSignin.configure({
hostedDomain: 'mycompany.com' //doesn't do anything
});
const user = await GoogleSignin.currentUserAsync();
console.log('User: ',user);
this.setState({user});
}
catch(err) {
console.log("Play services error", err.code, err.message);
}
}
_signIn() {
GoogleSignin.signIn()
.then((user) => {
console.log('User: ',user);
this.setState({user: user});
})
.catch((err) => {
console.log('WRONG SIGNIN', err);
})
.done();
}
_signOut() {
GoogleSignin.revokeAccess().then(() => GoogleSignin.signOut()).then(() => {
this.setState({user: null});
})
.done();
}
render(){
if (!this.state.user){
return (
<View style={{flex: 1}}>
<View style={{flex: 1.5, alignItems: 'center', justifyContent: 'center', marginTop: 40}}>
<Image
style={{width: 156, height: 156, resizeMode: 'contain'}}
source={require('../../assets/img/google_logo1600.png')} />
<Text style={{fontSize: 32, fontWeight: 'bold'}}>
Google Identity
</Text>
<Text style={[{fontSize: 15, paddingTop: 5}]}>
To continue, please sign-in.
</Text>
</View>
<View style={{flex: 1, alignItems: 'center', justifyContent: 'center', marginBottom: 40}}>
<GoogleSigninButton
style={{width: 312, height: 48}}
size={GoogleSigninButton.Size.Wide}
color={GoogleSigninButton.Color.Light}
onPress={() => this._signIn()}/>
</View>
</View>
);
} else {
return (
<View style={{flex: 1}}>
<View style={{flex: 1.5, alignItems: 'center', justifyContent: 'center', marginTop: 40}}>
<Image
style={{width: 156, height: 156, resizeMode: 'contain'}}
source={require('../../assets/img/google_logo1600.png')} />
<Text style={{fontSize: 32, fontWeight: 'bold'}}>
Google Identity
</Text>
<Text style={[{fontSize: 15, paddingTop: 5}]}>
To continue, please sign-in.
</Text>
</View>
<View style={{flex: 1, alignItems: 'center', justifyContent: 'center', marginBottom: 40}}>
<Button style={{width: 312, height: 48, backgroundColor: '#4385F2', color: 'white'}} title="Log Out" onPress={() => this._signOut()} />
</View>
</View>
)
}
}
}
If there's a better way to do this, I'm all ears. Thanks!
