Cloudflare 404 for not excluded files in _routes.json with trailingSlash option

[korywka]

Describe the bug

If we have 100+ routes (actually ~4000) for prerender all routes that are NOT in excluded list:

"exclude":["/_app/*","/.DS_Store","/favicon.png","/global.css","/vite-manifest.json","/","/__data.json","/bin/vimdiff","/bin/vimdiff/__data.json"

like /bin/cat gives 404. But we have bin/cat/index.html file locally. So prerender works 100% correct. It is not missing file.

Removing export const trailingSlash = 'always'; seems like fixed that. It was quite easy after finding issue #8422 and need to check that prerendered pages (with/without trailing slashes) will still work with this setup. statement :)

Reproduction

This 4000+ routes are rendered from private SQLite, but I can share this project with some of your developers by email.
Video: #8708 (comment)

Logs

No response

System Info

System:
    OS: macOS 13.1
    CPU: (10) arm64 Apple M1 Pro
    Memory: 87.28 MB / 16.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 19.4.0 - /opt/homebrew/bin/node
    npm: 9.2.0 - /opt/homebrew/bin/npm
  Browsers:
    Chrome: 109.0.5414.87
    Safari: 16.2
  npmPackages:
    @sveltejs/adapter-auto: 1.0.2 => 1.0.2 
    @sveltejs/kit: 1.2.6 => 1.2.6 
    svelte: 3.55.1 => 3.55.1 
    vite: 4.0.4 => 4.0.4

Severity

serious, but I can work around it

Additional Information

No response

[eltigerchino]

The behaviour you're looking for can be achieved by changing prerender to 'auto':

// +page.js
export const prerender = 'auto'; // server will redirect '/bin/cat' to '/bin/cat/'
export const trailingSlash = 'always';

or you can include this in the file /static/_redirects to use Cloudflare Pages Redirects:

/bin/* /bin/:splat/

When using prerender = true, SvelteKit does not automatically redirect trailing slashes and vice-versa.
This is the same for all adapters.

With prerender = true and:

• trailingSlash = 'always' , navigating to /bin/cat will result in a 404.
• trailingSlash = 'never' (the default), navigating to /bin/cat/ will result in 404.
• trailingSlash = 'ignore', navigating to /bin/cat/ will result in 404.

Perhaps this can be documented more thoroughly for people looking to retain the trailing slash redirection.

[korywka]

The most weird thing is that ~100 routes work correctly (that are excluded in cf routes config), and ~3900 are 404.

Imho, behavior should be consistent anyway.

[eltigerchino]

The most weird thing is that ~100 routes work correctly (that are excluded in cf routes config), and ~3900 are 404.

I'd assume that Cloudflare is doing the redirection for the excluded routes.

The rest of the 3900 are being routed to the SvelteKit Cloudflare function, which doesn't have the routes in its manifest because of prerender = true. Changing this to prerender = 'auto' ensures they're included.

I set up this reproduction to test the behaviour of the trailingSlash option.
Running npm run build && npm run preview then navigating to /test/1 will result in a 404 despite /test/1/ being in the excluded list in /.svelte-kit/cloudflare/_routes.json

[korywka]

I will fake data and share my project. I need some time. Thank you for your interest.

[korywka]

@s3812497 please, take a look at this video:

with-slash.mov

I am preparing the project.

[korywka]

I will not make video without export const trailingSlash = 'always'; cause it works as expected.

[eltigerchino]

@s3812497 please, take a look at this video:

with-slash.mov

Interestingly, I can access the prerendered page data https://5f68ec0e.binaries-web.pages.dev/bin/cat/__data.json but not the prerendered page itself https://5f68ec0e.binaries-web.pages.dev/bin/cat/index.html

Now I wonder if removing all the entries in exclude for _routes.json will cause the other prerendered routes to exhibit the same buggy behaviour.

[korywka]

You are right! __data.json is accessible, but not the .html! It is some kind of magic 🙂