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Todo list with universal JavaScript & Progressive Enhancement

This example app renders HTML on the server and on the client using “universal” JavaScript. It uses Node.js, React, React-Router and Redux for the rendering and the UI logic. For storing the todos on the server, it uses the key-value database LevelDB.

There’s also a Preact version available in the preact branch if you prefer that over React.

There are several good example apps and boilerplates for universal React/Preact apps. This one borrows ideas from Milo Mordaunt’s great tutorial: Handcrafting an Isomorphic Redux Application (With Love) and the corresponding repository.

What’s special about this example is that it’s made with Progressive Enhancement in mind. Instead of just rendering the first page on the server to improve the JavaScript application’s startup time, this example works entirely when JavaScript is disabled or fails for any reason. See these articles for background information:

When it comes to data fetching, this example follows Milo Mordaunt’s approach. It declares the data dependencies in the React/Preact component. The static component property needs lists Redux action creators.

These action creators directly talk to the database when called on the server, or make a request to the server when called on the client. It gets simpler if you use a separate HTTP REST API server that speaks JSON. Then you can use a universal HTTP library like axios or fetch to talk with the API server. In this simple example though, everything is mashed up on purpose.

Development server

Start the development server with:

$ npm install
$ npm start

Then open http://localhost:3333 in your browser.

Production server

Make a client and server production build:

$ npm run build

Start the server with:

$ npm run server:production

Then open http://localhost:3333 in your browser.