In this section, you’ll learn how you can implement authentication functionality with Apollo to provide signup and login features to your users.
As in the sections before, you’ll set the stage for the login functionality by preparing the React components that are needed for this feature. You’ll start by building the
Let’s quickly understand the structure of this new component, which can have two major states:
inputfields for the user to provide their
password. Notice that
truein this case.
inputfield where users can provide their
name. In this case,
_confirm will be used to implement the mutations that we need to send for the login functionality.
Next you also need to provide the
constants.js file that we use to define the key for the credentials that we’re storing in the browser’s
Warning: Storing JWTs in
localStorageis not a safe approach to implement authentication on the frontend. Because this tutorial is focused on GraphQL, we want to keep things simple and therefore are using it here. You can read more about this topic here.
With that component in place, you can go and add a new route to your
Finally, go ahead and add a
Link to the
Header that allows the users to navigate to the
You first retrieve the
authToken from local storage. If the
authToken is not available, the submit-button won’t be rendered any more. That way you make sure only authenticated users can create new links.
You’re also adding a second button to the right of the
Header that users can use to login and logout.
Here is what the ready component looks like:
Perfect, you’re all set now to implement the authentication functionality.
login are two regular GraphQL mutations you can use in the same way as you did with the
createLink mutation from before.
Both mutations look very similar to the mutations you already saw before. They take a number of arguments and return the
token that you can attach to subsequent requests to authenticate the user (i.e. indicate that a request is made on behalf of that user). You’ll learn 🔜 how to do so.
Before we take a closer look at the
<Mutation /> component implementation, go ahead and add the required imports.
Now, let’s understand what’s going with the
<Mutation /> component you just added.
The code is pretty straightforward. If the user wants to just login, you’re calling the
loginMutation, otherwise you’re using the
signupMutation, and the mutation will be triggered on the div’s
onClick event. GraphQL mutations receive the
name state values as params passed on the
variables prop. Lastly, after the mutation has finished, we call the
_confirm function, passing the
data returned by the mutation as an argument.
All right, all that’s left to do is implement the
After the mutation was performed, you’re storing the returned
localStorage and navigating back to the root route.
Note: Mutation returned
datarelies on GraphQL mutation definition, that’s why we need to get the
tokendepending on which mutation is triggered.
You can now create an account by providing a
password. Once you did that, the submit-button will be rendered again:
If you haven’t done so before, go ahead and test the login functionality. Run
yarn start and open
http://localhost:3000/login. Then click the need to create an account?-button and provide some user data for the user you’re creating. Finally, click the create account-button. If all went well, the app navigates back to the root route and your user was created. You can verify that the new user is there by sending the
users query in the dev Playground in the database project.
Now that users are able to login and obtain a token that authenticates them against the GraphQL server, you actually need to make sure that the token gets attached to all requests that are sent to the API.
Since all the API requests are actually created and sent by the
ApolloClient instance in your app, you need to make sure it knows about the user’s token! Luckily, Apollo provides a nice way for authenticating all requests by using the concept of middleware, implemented as an Apollo Link.
First, you need to add the required dependencies to the app. Open a terminal, navigate to your project directory and type:
Let’s see the authentication link in action!
This middleware will be invoked every time
ApolloClient sends a request to the server. Apollo Links allow you to create
middlewares that let you modify requests before they are sent to the server.
Let’s see how it works in our code: first, we get the authentication
localStorage if it exists; after that, we return the
headers to the
httpLink can read them.
Note: You can read more about Apollo’s authentication here.
That’s it - now all your API requests will be authenticated if a
token is available.
The last thing you might do in this chapter is check how to ensure only authenticated users are able to
post new links. Plus, every
Link that’s created by a
post mutation should automatically set the
User who sent the request for its
With this, you’re extracting the
userId from the
Authorization header of the request and use it to directly
connect it with the
Link that’s created. Note that
getUserId will throw an error if the field is not provided or not valid token could be extracted.