Hi, I made a mistake with this message in that widgets/interact is not relevant. I was confused because the SageCell server just happened to randomly stop working (or be slow) **coincidentally** exactly when I was trying widgets. Of course nothing at all works without CORS setup properly, and when it is, then normal output and widgets work equally well.
That said, I still think a better error message and documentation related to CORS rather than silently failing might be better. -- William On Wed, Jan 29, 2020 at 11:20 AM William Stein <[email protected]> wrote: > > Hi Andrey (and the sage-cell list), > > I was just demoing the Sage cell server, and hit a confusing issue: > > If you use an interact at https://sagecell.sagemath.org/ like this > then it works fine: > > @interact > def f(n=2020): > print(factor(n)) > > But if you embed an interact in a "random" static site via the simple > directions, then it is completely broken (email will probably mangle > this, but you get the point, and I also attached a screenshot). By > "broken" I mean that there is a spinner forever and no output appears: > > <script > src="https://sagecell.sagemath.org/static/embedded_sagecell.js";></script> > <script>sagecell.makeSagecell({"inputLocation": ".sage"});</script> > > <div class="sage"> > <script type="text/x-sage"> > @interact > def f(n=2020): > print(factor(n)) > </script> > </div> > > The interacts at https://wiki.sagemath.org/interact *do* work though. > > If you expand a sage cell at > http://linear.ups.edu/html/section-SSLE.html then try to put an > interact in it, that also does NOT work. > > Of course, actually looking at the console log reveals the problem: > > Access to XMLHttpRequest at > 'https://sagecell.sagemath.org/kernel?CellSessionID=7dce1ecb762c41868c96f9af39df6ea8&timeout=0&accepted_tos=true' > from origin 'https://cocalc.com' has been blocked by CORS policy: > Request header field x-xsrftoken is not allowed by > Access-Control-Allow-Headers in preflight response. > > So to get widgets to work with the sagecell server, I have to > configure the site hosting my static html to allow certain types of > cross domain access that is denied by default. That's all fine and > good, but... > > (1) is there anything documented anywhere about issues with CORS + > sagecell server? I googled and could find absolutely nothing at all, > and no issues in the sagecell issue tracker. > > (2) Wouldn't it be nice if instead of the output just spinning forever > and things being broken, the client sagecell could say "sorry, widgets > are not available due to the CORS policy of the hosting website. > Please see this link for more details...." or something like that? > > Just curious if this has come up before, or should I create a ticket at > > https://github.com/sagemath/sagecell/issues > > ? > > > > -- > William (http://wstein.org) -- William (http://wstein.org) -- You received this message because you are subscribed to the Google Groups "sage-cell" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-cell/CACLE5GA6%2ByCXrX-n-hE1VXmGg-KUpFtOtTX_7iL-ZWZKAgzQyg%40mail.gmail.com.
