Webassembly, wasm files, webservers and MIME types

adding_wasm_MIME.md

When compiling client files to webassembly, usually you'll end up with both .js and .wasm files. By default, most webservers don't know about the wasm MIME type. You'll likely see the following error: wasm streaming compile failed: TypeError: Failed to execute 'compile' on 'WebAssembly': Incorrect response MIME type. Expected 'application/wasm'.

Here is how to add the wasm MIME type (on linux systems, apache + nginx):

Open /etc/mime.types You'll see two columns, media type on the left, file type on the right Add the line application/wasm wasm

Restart your webserver and you're good to go. This will work for Apache and also the Python SimpleHttpServer.

If you're using Nginx, you'll have to edit Nginx's mime types located in /etc/nginx/mime.types Reload nginx for the changes to take effect: sudo systemctl reload nginx

I've been searching for a way to declare the mime type for wasm on an aws s3 bucket (static site) - no luck so far

Mr. corbin-c may i ask how you send the file with Content-Type: application/wasm & Content-Encoding: gzip in ngnix webserver? I have this problem with my webserver. ( https://prnt.sc/10bfog7 ) (here is the problem in screenshot)

@stevendamianakis (https://docs.unity3d.com/Manual/webgl-server-configuration-code-samples.html) this might help , there is a sample for multiple servers(Nginx, Apache) config file so that it will support gzip compression and fix the wasm error(MIME type).