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Installation

Terminal
npm install @runonatlas/express

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Initialization

This only covers the backend initialization with Express. You will also need to initialize your frontend. For example, React or Next.js.

Initializing the Atlas SDK is very easy. You just need to follow these steps:

1

Set the Atlas API key in the environment variables

You can get it from the Atlas Dashboard.

.env
ATLAS_API_KEY="INSERT_YOUR_ATLAS_API_KEY"
2

Create the Atlas Express Client

To initialize the Atlas SDK, you need to instantiate the Atlas Client with the following parameters:

  1. Your Atlas API key.
  2. A function that returns the user id given a request object.

When using Clerk, you just need to pass the getAuth function to get the userId.

import { AtlasExpressClient } from "@runonatlas/express";
import { getAuth } from "@clerk/express";
import express from "express";

const app = express();
const atlas = new AtlasExpressClient(
  (req) => getAuth(req).userId
);

app.use("/", atlas.router);

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Restrict user access based on their subscriptions

You can prevent users from accessing restricted parts of your application based on their subscription. To do so, you can use our backend protection features.

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Backend Protection

In order to prevent users from using certain endpoints unless they have a plan with the required features, we only need to add a middleware.

app.post(
  "/api/generate-caption",
  atlas.createFeaturesMiddleware(["data-explorer"]), // Add this line
  (req, res) => {
    // Your endpoint logic here
  }
);

This will automatically prevent users who don’t have the data-explorer feature in their active plan from accessing the endpoint.

Remember that you need to have followed the installation guide before you can use any of these features.

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Limit-based features

Sometimes, just having a feature as enabled or disabled is not enough, and our pricing models require limits to be set. For example, 5 users per account, or 20GB of storage. Setting this up with Atlas is very easy. And, if at some point the limits change, you won’t need to change the code again!

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Configuring the backend

The backend needs to understand what the limits are and how to check if the limit has been reached. To do so, when initializing the Atlas Client, you can provide a limits object with callbacks per each limit that you might want to use.

For example, given a feature whose id is data-explorer, you can provide a callback to check if the limit has been reached:

src/index.ts
import { AtlasExpressClient } from "@runonatlas/express";
import express from "express";
import { getAuth } from "@clerk/express";
import { prisma } from "./db";

const app = express();
const atlas = new AtlasExpressClient(
  (req) => getAuth(req).userId,
  {
    limits: {
      "data-explorer": (userId: string) => prisma.explorations.count({
        where: {
          userId,
        },
      }),
    },
  }
);

// ... Remaining code

Now, every time you the application needs to check if the data-explorer feature is available, Atlas will use the callback to compute it.