How and when to strip the url to serve a static site?

Question

I have the following directory structure for my static web site:

│   infinote.exe
└───spa
    │   favicon.ico
    │   index.html
    │
    ├───css
    │       app.f99f51d4.css
    │       vendor.d9e2261d.css
    │
    ├───fonts
    │       flUhRq6tzZclQEJ-Vdg-IuiaDsNa.40fa1be9.woff
    │       flUhRq6tzZclQEJ-Vdg-IuiaDsNcIhQ8tQ.cf9862e8.woff2
    │       KFOkCnqEu92Fr1MmgVxIIzQ.9391e6e2.woff
    │       KFOlCnqEu92Fr1MmEU9fBBc-.ddd11dab.woff
    │       KFOlCnqEu92Fr1MmSU5fBBc-.877b9231.woff
    │       KFOlCnqEu92Fr1MmWUlfBBc-.0344cc3c.woff
    │       KFOlCnqEu92Fr1MmYUtfBBc-.b555d228.woff
    │       KFOmCnqEu92Fr1Mu4mxM.9b78ea3b.woff
    │       PatuaOne-Regular.ttf
    │       Poppins-Regular.ttf
    │
    ├───icons
    │       apple-icon-120x120.png
    │       apple-launch-828x1792.png
    │       favicon-128x128.png
    │       favicon-16x16.png
    │       favicon-32x32.png
    │       favicon-96x96.png
    │       icon-128x128.png
    │       safari-pinned-tab.svg
    │
    └───js
            app.3a5b0240.js
            vendor.a9a3886c.js

infinote.exe is a binary compiled from Go and the line where I define how to serve the web site is

r.Handle("/spa/", http.StripPrefix("/spa/", http.FileServer(http.Dir("./spa"))))

I use chi as the router, and r := chi.NewRouter().

I expect http://example.com/spa/ to:

• first request http://example.com/spa/ → this is ./spa/index.html
• and then after parsing index.html, to request other files in ./spa
  • An example would be http://example.com/spa/js/vendor.a9a3886c.js → ./spa/js/vendor.a9a3886c.js

What happens is that index.html is retrieved correctly, and then all the referenced files return a 404 Not Found.

To be frank I do not exactly understand the mechanics (and need) of http.StripPrefix. Is this because the files in spa are relative to the full URL, in other words to ./spa/spa/...- which is not correct (and thus the need to strip app first)?

If so, why is only index.html retrieved correctly? Even favicon.ico is a 404 despite being in the same directory as index.html.

Answer 1

All credit goes to @mkopriva and @Zombo whose comments were, for some reason, deleted

After several iterations and tests, I managed to find a working version:

r.Handle("/spa/*",http.StripPrefix("/spa/", ttp.FileServer(http.Dir("spa"))))

The key part was the * in the first "pattern". I did not find anything about wildcards in the documentation but with a * it works - and without it does not (I get the 404`).

I would be delighted to have an answer that is better than that