Unlock Seamless Authentication in Your React Native App

Setting Up Your Development Environment

Before we dive in, make sure you have the following configuration:

• Node version ≥10.x.x installed
• A package manager like npm or Yarn
• react-native-cli installed on your local machine
• React Native version ≥0.60.x (we’re using version 0.64.0 in this tutorial)

If you need help setting up a development environment for React Native, check out the official documentation.

Creating a New React Native Project

Let’s create a new React Native project. First, create a directory for your code and navigate into it. We’ll use the name “RNauthflow” throughout this tutorial, but feel free to choose your own name.

npx react-native init RNauthflow

Installing Dependencies and Setting Up React Navigation

Once the project setup is complete, install the required dependencies:

npm install or yarn install

To finalize the installation on iOS, install pods using CocoaPods.

Storing Tokens with Async Storage

We’ll use the react-native-async-storage/async-storage npm package to store tokens. Install it using:

npm install @react-native-async-storage/async-storage or yarn add @react-native-async-storage/async-storage

Then, create a utility function to store tokens:

import { AsyncStorage } from '@react-native-async-storage/async-storage';

const storeToken = async (token) => {
  try {
    await AsyncStorage.setItem('token', token);
  } catch (error) {
    console.error('Error storing token:', error);
  }
};

Creating the Auth Context

We’ll use the React Context API to manage our project state. Create a simple auth context and implement the provider components:

import { createContext, useReducer, useMemo } from 'eact';

const AuthContext = createContext();

const authReducer = (state, action) => {
  switch (action.type) {
    case 'SIGNIN':
      return {...state, authToken: action.token };
    case 'SIGNOUT':
      return {...state, authToken: null };
    default:
      return state;
  }
};

const AuthProvider = ({ children }) => {
  const [state, dispatch] = useReducer(authReducer, { authToken: null });

  const signIn = (token) => dispatch({ type: 'SIGNIN', token });
  const signOut = () => dispatch({ type: 'SIGNOUT' });

  const authActions = useMemo(() => ({ signIn, signOut }), []);

  return (
    <AuthContext.Provider value={{ state, authActions }}>
      {children}
    </AuthContext.Provider>
  );
};

Adding Screens and Navigation

Create two new screens, HomeScreen and LoginScreen, inside the src/screens/ directory. These screens will handle login and authentication. We’ll use React Navigation v5, which follows a component-based approach:

import { createStackNavigator } from '@react-navigation/stack';
import { NavigationContainer } from '@react-navigation/native';

const Stack = createStackNavigator();

const App = () => {
  return (
    <NavigationContainer>
      <Stack.Navigator>
        {/* Add your screens here */}
      </Stack.Navigator>
    </NavigationContainer>
  );
};

Using the Reusable Auth Flow

Wrap your Root(App) component with the AuthProvider, and you’re ready to use your reusable auth flow:

import React from 'eact';
import { AuthProvider } from './AuthProvider';

const App = () => {
  return (
    <AuthProvider>
      <Root>
        {/* Add your app content here */}
      </Root>
    </AuthProvider>
  );
};

With this generic solution, you can easily integrate authentication with Firebase, Okta, Auth0, and more. Check out the complete code used in this demo on GitHub.