React Starter Kit and Material UI: userAgent should be supplied in the muiTheme context for server-side rendering

Question

With the React Starter Kit, I add Material UI as follows:

npm install material-ui --save

and the following import to a component:

import RaisedButton from 'material-ui/lib/raised-button';

and:

<RaisedButton label="Default" />

I get the following error:

Warning: Material-UI: userAgent should be supplied in the muiTheme context for server-side rendering.

According to Material UI's documentation, it says I'd need to address three things:

1. autoprefixer and the user agent
2. process.env.NODE_ENV

What code should I put in and where exactly, specifically with the React Starter Kit?

P.S. this solution does not work for me :-/

Answer 1

When using Material-UI with server rendering, we must use the same environment for the server and the client. This has two technical implications.

as you seen on MaterialUI documentation page

You need to provide the same user-agent for both server and browser contexts as you seen it in documentation, but, I strongly discourage you to provide a "all" user-agent, since you will serve a lot of unnecessary code to your end-user.

Instead you can easily follow MaterialUI doc and pass user-agent value contained in http request headers.

With an express or koa server

global.navigator = global.navigator || {};
global.navigator.userAgent = req.headers['user-agent'] || 'all';

I just checked it has been added to the ReactStarterKit (not tested myself) in src/server.js

global.navigator = global.navigator || {};
global.navigator.userAgent = global.navigator.userAgent || 'all';