Radiks-server keeps all models inside of a collection. You can use the `getDB` function to access this collection from inside your application.
```js
const { getDB } = require('radiks-server');
const mongo = await getDB(MONGODB_URL);
```
[See the MongoDB Collection reference](https://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html) for documentation about how you can interact with this collection.
If you're using an [express.js](https://expressjs.com/) server to run your application, it's probably easiest to use the Radiks-server middleware. This way, you won't have to run a separate application server and Radiks server.
Radiks-server includes an easy-to-use middleware that you can include in your application:
```javascript
const express = require('express');
const { setup } = require('radiks-server');
const app = express();
setup().then(RadiksController => {
app.use('/radiks', RadiksController);
});
```
The `setup` method returns a promise, and that promise resolves to the actual middleware that your server can use. This is because it first connects to MongoDB, and then sets up the middleware with that database connection.
The `setup` function accepts an `options` object as the first argument. If you aren't using environment variables, you can explicitly pass in a MongoDB URL here:
Migrating data from Firebase to Radiks-server is simple and painless. You can create a script file to fetch all the Firebase data using their API. Then, you can use your `MONGOD_URI` config to use the `mongodb` npm package.