Resources not filtered when HTTP 304

[thijskh]

When filter resources is enabled, I still see (gray) lines for some png, css and js. I strongly suspect these are resources that return an 304 Not Modified HTTP response.

Looking at the code I think it's this part that makes them not filtered: no content-type is sent in this case, so true is returned: https://github.com/UNINETT/SAML-tracer/blob/bfa10c1d50ba98bcd40aeab66efd6dfc62d36935/src/SAMLTrace.js#L435-L439

Not sure what a good solution is: special case 304 and also don't display any 304 reponses when filter resources is enabled?

[khlr]

Well, the function could be extended to look at the request headers (instead of the response headers, only), if the response is a 304. In that case it could check if the request headers contained preconditions and then hide the request.

It's a bit difficult to reproduce this. Could you supply an exported trace with a 304? I think I can fiddle around with that then ;-)

[tvdijen]

SAML-tracer-export-2023-10-10T07 26 31.558Z.json.txt

I see it on HTTP/200 resources as well. Trace attached, but note I had to rename it to .txt to be able to upload it here. Could it perhaps be related to HTTP/2.0 ?

Update: Strange detail though: I now can't reproduce this myself.. When I try and make the same trace again, the same file is being filtered (no cache, exact same response)

[khlr]

Unfortunately the request you highlighted isn't contained in the exported file at all. Or am I missing something? 👀

[tvdijen]

You are right, I'll upload a new trace tomorrow.. The trace was made after the screenshot and I suspect browser cache from not requesting the resource on the second run

[tvdijen]

I'm sorry, I can no longer reproduce this. The issue still exists for the .woff2 files though (content-type: font/woff2)

[thijskh]

The woff issue I might have fixed in 83bc59cb7e345d7a14aafc59af047959966c821a, without noticing you proposed a similar fix for that at the same time. But right after decided on a more structural approach in #92.

[thijskh]

I don't see 304 resources anymore when filtering is on.

What I do still see are grey resources in the list. These are all requests that are raced, accourding to devtools. The SAML tracer does not have a response for them, just the request. Therefore I think we cannot really know they are resources at all, since we don't have a mime type.

[tvdijen]

The woff issue I might have fixed in 83bc59c, without noticing you proposed a similar fix for that at the same time. But right after decided on a more structural approach in #92.

Yes, yours is much butter!

[thijskh]

So all in all, maybe just close this?

[tvdijen]

Agreed!