search

ghcjs / jsaddle

JavaScript interface that works with GHCJS or GHC
118 stars 63 forks source link

Error : Unexpected Duplicate. with Warp backend. #64

Open sheganinans opened 6 years ago

sheganinans commented 6 years ago

I keep getting this error when using the jsaddle-warp backend. However the same exact reflex widget when using jsaddle-webkit2gtk will work perfectly fine.

To replicate this error:

git clone --recurse-submodule https://github.com/sheganinans/reflex-warp
cd reflex-warp
reflex-platform/try-reflex
nix-shell -A shells.ghc
cabal new-repl warp-reflex
main

Connect a web browser to http://localhost:3911, and click the button a few times and check the output in the cabal repl. Soon enough the error will show up and the webapp will freeze.

However if you instead run cabal new-repl webkit-reflex and try pushing the button, the app will work exactly as expected.

sheganinans commented 6 years ago

Any luck on the replication of this bug? I tried it on a different installation of NixOS and got the same behavior.

nomeata commented 6 years ago

Does the browser freeze with high CPU usage? That’s what I am observing here at least…

nomeata commented 6 years ago

According to https://www.reddit.com/r/haskell/comments/88k18x/monthly_hask_anything_april_2018/dwm8qzr/ it is a Firefox-specific problem, and using Chrome avoids it.

schell commented 5 years ago

I see this too, it’s a bummer because FF is my main browser. Any headway?

schell commented 5 years ago

@3noch - you seem to have some insight into this bug. What exactly is the problem on FF?

vincent-prz commented 4 years ago

Upping this issue, as I really care about not having to use Chrome to use JSaddle.

niteria commented 4 years ago

I took a look at this and minimized the example to https://github.com/niteria/jsaddle-repro

As expected it works in Chrome Version 81.0.4044.122 (Official Build) (64-bit) and fails on Firefox 77.0.1 (64-bit).

This is using the latest jsaddle and jsaddle-warp, version 0.9.7.0 for both.

niteria commented 4 years ago

Ok, this is really the same as https://github.com/ghcjs/jsaddle/issues/51. It fails in Firefox because Firefox completely disallows synchronous XHR requests. Chrome is less strict.

There's sync-xhr that's supposed to allow this https://featurepolicy.info/policies/sync-xhr, but it's not implemented on Firefox.

danwdart commented 3 years ago

So would the solution be only using async xhr?

danwdart commented 3 years ago

Seems to be the same as https://github.com/ghcjs/jsaddle/issues/54 too maybe

danwdart commented 2 months ago

Has progress been made towards this? I've been compiling to JS every time since seeing this issue - seeing as the default browser on deployments gets what looks like memory leaks.