inconsistencies with routing patterns with single page app mode (wrangler/vite)

[threepointone]

What versions & operating system are you using?

MacOS, wrangler@4.16.1, @cloudflare/vite-plugin@1.2.4

Please provide a link to a minimal reproduction

https://github.com/threepointone/test-wrangler-vite-spa-routing-patterns

Describe the Bug

There are some bugs with routing patterns with both wrangler and the vite plugin when run in "singlae page app mode". I made a repro here https://github.com/threepointone/test-wrangler-vite-spa-routing-patterns, but including the results in this issue as well.

Assume we have an assets directory that looks like this:

public/
  index.html
  xyz.html
  abc/
    index.html
    def.html

with a configuration (as in wrangler.jsonc) that looks like this:

{
  // ...
  "assets": {
    "directory": "public",
    "not_found_handling": "single-page-application"
  }
}

Here's a table of paths, expected files to be loaded, and what files actually get loaded.

Path	Expected	Actual (wrangler)	Actual (vite)
/	index.html	index.html ✅	index.html ✅
/xyz	xyz.html	xyz.html ✅	index.html ❌
/xyz/asdasd	index.html	index.html ✅	index.html ❌
/abc/	abc/index.html	abc/index.html ✅	index.html ❌
/abc/def	abc/def.html	abc/def.html ✅	index.html ❌
/abc/def/ghi	abc/index.html	index.html ❌	index.html ❌

Please provide any relevant error logs

No response

[petebacondarwin]

The last line in the table is how single-page-application mode was designed to work.

/abc/def/ghi -> index.html 

Requests that would have 404ed will be rewritten to the content of the index.html at the root of the asset directory.

This is different to how the 404-page mode works, where it finds the "nearest" asset with filename of 404.html.

[petebacondarwin]

The other lines in the table where the Vite plugin diverges from the wrangler (and production) behaviour are valid bugs that need fixing. It is actually dependent upon the html_handling configuration. See https://developers.cloudflare.com/workers/static-assets/routing/advanced/html-handling/.

[jamesopstad]

Putting HTML in the public directory is a bit of an anti-pattern in Vite. See https://vite.dev/guide/build.html#multi-page-app. We should still support it but loading subdirectory index.html files does work if you do it the Vite way. Not sure what you mean about it being dependent on the html_handling @petebacondarwin?

I'm curious what your expectations are when you have HTML files inside and outside the public directory that match the same path (such as the root index.html in the reproduction)? The order of precedence here isn't clear and is actually inconsistent in Vite without the Cloudflare plugin. An exact match will favour the public directory at dev time (because the public middleware is earlier in the chain) but this file will be overwritten at build time.

[petebacondarwin]

When you request /abc/ then if html_handling is default (set to "auto-trailing-slash") then Assets will redirect the browser to /abc/index.html if that file exists in the uploaded assets.

[jamesopstad]

When you request /abc/ then if html_handling is default (set to "auto-trailing-slash") then Assets will redirect the browser to /abc/index.html if that file exists in the uploaded assets.

It won't redirect the browser to /abc/index.html. It will serve /abc/index.html at /abc/. If you request /abc it will redirect to /abc/.

[petebacondarwin]

Sorry. Right. I meant that, depending upon html_handling, requesting /abc/ can do different things, including redirecting.