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MIME type error with express.static and CSS files

I’m using Express and NodeJS. In my server.js file I have this piece of code:

app.use(express.static('/static'));

And subsequently in my static directory, I have a CSS folder, and then a style.css file. In my index.html, I link to the sheet like so:

  <link rel="stylesheet" type="text/css" href="/static/css/style.css">

However, in my test environment I continue to get this error:

Refused to apply style from ‘http://localhost:3500/static/css/style.css’ because its MIME type (‘text/html’) is not a supported stylesheet MIME type, and strict MIME checking is enabled.

I am sure that my path name in my tag is right, and I’m confused to why I’m getting this error.

Do I need to declare that CSS files be processed as CSS and not HTML? Am I not doing that when I say type="text/CSS"? If not, what do I need to put into my server file to remedy this issue?

Answer

The MIME Type Error is happening because the file served is likely a “404 Not Found” page made by Express, because it couldn’t locate the CSS file. The browser expects a CSS file, gets an HTML file and says the MIME Type doesn’t fit.

app.use(express.static('/static'));

means that the static files are served literally from /static. In a Unix-Based Operating System, this is a direct child to the directory root /. I don’t think you do, but you shouldn’t store files, let alone publicly accessible files in that directory. Instead what you are probably looking for is the static directory in your App’s directory.

This is how you can tell express to use that one to server files:

app.use(express.static(__dirname + "/static"));

If you can’t include a file in your HTML always double, or better even tripple check, that the file can be accessed through the browser first.

Also, the files are then located in ... href="/...", not ... href="/static/..."