How to use Auth0 with Node.js and Express

Maria J. Danford

Cloud-primarily based authentication and authorization platforms—sometimes known as IDaaS, or identification as a service — are an growing place of cloud tooling, and it’s effortless to see why. Application stability is complicated and mistake-susceptible, and pretty much each challenge needs it. The potential to offload much of the get the job done to a committed and demonstrated service is engaging.

Auth0 is an up-and-coming company of authentication and authorization products and services (and open supply software package). In this article, you will see how to incorporate Auth0 log-in capabilities into a application with a Node.js/Express again conclude, serving a straight JS entrance conclude, and then use the authenticated person data (through JWT) to demonstrate/disguise UI info and safe RESTful endpoints.

Generate a simple Node.js/Express application

Initial you will established up a simple Express application. Begin by typing npm init from the command line. You can offer whichever values you like for the challenge title and so on. The remaining code from the challenge is out there below. Note that this sample application is supposed to spotlight the stability things in a simple and condensed fashion, so numerous production-required capabilities like mistake managing and configuration data files have been remaining out.

Up coming, install Express from the similar listing the place you ran init by running npm install convey.

In your code editor of selection, add a server.js file in the root listing and set the contents of Listing 1 in it.

Listing 1. Primary server.js file

  const convey = have to have('express')
  const application = convey()

application.get('/api/open', purpose(req, res)
    concept: "Open up Endpoint"

application.get('/api/users-only', purpose(req, res)
    concept: 'Members Only Endpoint'

application.get('/api/protected', purpose(req, res)
    concept: 'Protected Endpoint'

console.log('Listening on http://localhost:3000')

Listing 1 sketches out what we’re shooting for: three API endpoints, 1 open, 1 requiring an energetic log-in, and 1 requiring log-in and a particular authorization.

Now add a dev script to the script part of the package.json file:

"dev": "nodemon server.js"

You are going to have to have to install the nodemon resource:

npm install -g nodemon

You can now operate the simple server with npm operate dev, and check out the API responding at localhost:3000/api/open.

Serve static data files

We’ll use convey.static to serve the consumer from /general public/index.html. This file is going to comprise all the HTML and JS in 1 area to make it effortless to comprehend all the things. This will be our consumer — what the Auth0 docs refer to as a solitary-webpage application (SPA). Our consumer will make calls to the again-conclude API we described earlier mentioned.

Just in advance of the application.listen line in server.js, add the next line:

application.use(convey.static(be a part of(__dirname, "general public")))

This instructs Node.js to serve the data files in /general public. Now produce the file /general public/index.html and set the contents of Listing two in it.

Listing two. Starting index.html


Infoworld: Intro to Auth0



Fetch Open up API




Fetch Customers Only API




Fetch Guarded API





With Listing two, you can now go to localhost:3000/ and you will find a standard HTML webpage with the three buttons that strike the three endpoints. At this phase, if you click on the buttons, all three will return their effects due to the fact the safe endpoints are not safe however. Additional, the log-in and log-out buttons don’t do everything however, and the content material at the bottom of the webpage stays hidden.

Safe the endpoints

Now you are to the issue the place you have to have an Auth0 account, which is free of charge for standard use. You can indication up below. When you indication up, Auth0 will produce a default “System API” for you. This is a unique API that is 1-for each-tenant, and gives you entry to the Auth0 system. The general public keys (in this circumstance jwks for RS256) are uncovered through this API.

Up coming we will produce an API in the Auth0 method. This is a illustration of your actual-planet API (the endpoints we want to safe) that lets you to apply Auth0 capabilities. Click on the “Create API” button, which will open the screen you see in Determine 1.

Determine 1. Generate an Auth0 API

auth0 create api IDG

Determine 1.

For the title area, you can use everything that is unforgettable. For identifier, you should use a URL, but you don’t have to expose the URL or even personal it — it is just an identifier to which you will refer in your code. Of study course, in a actual-planet challenge, you would use your genuine domain title or other owned useful resource. For the last area on this variety, you can go away the algorithm as RS256.

Use the Auth0 API

The general public essential for the RS256 pair is now hosted for you at the URL with the format https://[your_domain] You can find the detail for your new API by clicking the “settings” website link by it. Discover the identifier you supplied now has the variety https://[your_domain] You will see the two of these URLs in motion soon.

The up coming little bit of housekeeping you have to do is to outline permissions. In this circumstance, you want a authorization that will be demanded for accessing the protected endpoint we made earlier. From the settings webpage, choose the “Permissions” tab. Generate a read through:protected authorization and strike the “Add” button.

In a moment you will apply this authorization to the protected endpoint.

Use the Express auth middleware

You are going to use Express middleware to enforce the authorization plan. Go in advance and install the dependencies in Listing 3, which consists of an Express JWT (JSON internet token), a JSON internet essential, and Express JWT authorization extensions, respectively. Keep in mind that JWT is an encrypted token that carries the auth info. It will be employed to communicate involving the entrance conclude, the again conclude, and the Auth0 system.

Listing 3. Increase auth dependencies

npm install --save convey-jwt jwks-rsa convey-jwt-authz

Increase checkJwt to server.js, together with the required imports, as seen in Listing four. Discover that there are things (in sq. brackets) that you will fill in with your particulars.

Listing four. Securing the endpoint

const jwt = have to have('express-jwt')
const jwtAuthz = have to have('express-jwt-authz')
const jwksRsa = have to have('jwks-rsa')
const checkJwt = jwt(
  magic formula: jwksRsa.expressJwtSecret(
    cache: correct,
    rateLimit: correct,
    jwksRequestsPerMinute: five,
    jwksUri: `https://[YOUR System API Domain]`

  issuer: [`https://[YOUR System API Domain]`],
  algorithms: ['RS256']
var possibilities = customScopeKey: 'permissions'  // This is required to guidance the direct-person permissions
const checkScopes = jwtAuthz([ 'read:protected' ])

application.get('/api/users-only', checkJwt, purpose(req, res)
    concept: 'Members Only Endpoint'

application.get('/api/protected', checkJwt, checkScopes, purpose(req, res)
    concept: 'Protected Endpoint'

In wide strokes, what is going on below is that we produce an Express middleware checkJwt that will verify for a legitimate JSON internet token. This is configured to use the info from the Auth0 API you made earlier.

Discover the two issuer and jwksUri issue to your System API account, which was made for you when you signed up. Once again, there is 1 System API account for each tenant, not for each API. This account offers the keys (the JSON Net Critical Established, in this circumstance) to indication the auth info for particular APIs.

The viewers area will refer to the identifier for the API you made, not the System API account.

Ultimately, recognize that there is also checkScopes applied to the protected endpoint. This checks for the read through:protected authorization.

Examine your development

At this issue, if you return to the browser and click on the “Members Only API” (or “Protected API”) button, the server will answer with an mistake:

UnauthorizedError: No authorization token was found.

That’s a good indication that matters are starting up to get the job done.

Generate an Auth0 consumer software

Just as you made an Auth0 API to model your again-conclude application, you are going to now produce and configure a consumer, or buyer, of your secured endpoints. Once again, Auth0 calls them SPAs (they employed to be termed just “Clients,” and however are in some of the Auth0 docs). Go to the Auth0 dashboard, and in the remaining-hand menu choose “Applications -> Apps,” just earlier mentioned the API website link you employed in advance of when configuring the server.

Now choose the “Create Application” button. Give it a title (most likely get in touch with it “Client” to distinguish it from the again-conclude application) and make absolutely sure to choose “SPA” as the variety. Strike “Create.”

Now open the consumer software by selecting from the listing. Herein you are going to find the data you have to have to established up the consumer facet of our check application: the domain and consumer ID. Make notice of this info we’ll use it in just a moment.

Configure the callback, logout, and Net Origin URLs in Application Options

Initial nevertheless, as seen in Determine two, add the localhost address (http://localhost:3000) for the dev application to the allowed callbacks. This lets Auth0 know it can use your improvement URL for these needs.

Determine two. Adding localhost to consumer config

auth0 calllback IDG

Determine two.

Construct out the consumer auth

Now return to the application code and add the Auth0 SDK to the consumer, in index.html. In this circumstance, we’ll use the CDN. Increase the next to the header of the file:

<script src="">script>

Now we can tie in the auth. Begin by wiring up the log-in and log-out buttons. The handlers for them are seen in Listing five.

Listing five. Log-in and log-out handlers

const configureClient = async () => 
        auth0 = await createAuth0Client(
          domain: "[YOUR System API URL]",
          consumer_id: "[YOUR Consumer ID]",
          viewers: "[YOUR API IDENTIFIER]" // The backend api id
const login = async () =>
        await auth0.loginWithRedirect(
          redirect_uri: "http://localhost:3000"
      const logout = () =>

With Listing five, to start with you configure your Auth0 consumer employing the settings info mentioned earlier. Discover all over again that the domain area refers to your 1-for each-tenant System API.

Both equally handlers rely upon the Auth0 library you imported earlier. If you apply this and refresh the application, you can click on the log-in button and be redirected to the Auth0 log-in webpage. This webpage is the “universal log-in” portal (Auth0 also supports integrating a “lock box” ingredient). Discover that it instantly supports the two username/password and social log-ins.

Demonstrate and disguise content material primarily based on auth

Listing 6 has a couple of more script alterations for index.html to apply demonstrate/disguise features.

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