Next.js SSR with client-side refresh example

This Next.js example demonstrates how to:

• Load initial data using getServerSideProps
• Keep data fresh on the client after the initial load using useSWR

The app is live on Vercel for demonstrative purposes.

How it works

1. A function defined in /utils/getData.js returns the data we want in our page. This function is imported and invoked in two locations:
   • In /pages/index.js, invoked in getServerSideProps
   • In /pages/api/data.js, invokes in the main request handler function
2. In /pages/index.js, getServerSideProps returns the initial data
3. In the main page function, initialData is passed as the value to useSWR’s initialData option, giving an immediate value that we can destructure
4. useSWR also has revalidateOnMount set to true, so the client immediately refreshes the data from /api/data when the page is hydrated
5. You could also configure useSWR to refresh on an interval to keep it fresh!