WeBWorK Problems

Library Browser Render Issues

Library Browser Render Issues

by Steven Marshall -
Number of replies: 5

I’m looking for help with an issue we have pulling in problems from the library Browser. When we attempt to pull in a problem set that contains images, we get 404 messages in the browser and broken links. When we look in the Apache error logs, we see:

[Tue Jan 07 12:57:03.592452 2020] [perl:error] [pid 1844] [client 10.0.10.38:53641] [/webwork2/instructorXMLHandler] Error message for command: searchLib \n<br/>faultcode: 404 \n<br/>faultstring: WebworkWebservice: Can't authenticate -- session may have timed out. \n<br/>End error message<br/>\n * in WeBWorK::ContentGenerator::instructorXMLHandler::content called at line 232 of /opt/webwork/webwork2/lib/WeBWorK/ContentGenerator.pm\n * in WeBWorK::ContentGenerator::go called at line 384 of /opt/webwork/webwork2/lib/WeBWorK.pm, referer: https://webwork.math.ou.edu/webwork2/casit_test/instructor/setmaker/

Use of uninitialized value $PARa in concatenation (.) or string at (eval 16745) line 40.
Subroutine GRvertices_labels_labels redefined at (eval 17294) line 1736, <MACROFILE> chunk 1.

I have attached a screen shot of the browser. Thanks!

Attachment wwerror.jpg
In reply to Steven Marshall

Re: Library Browser Render Issues

by Michael Gage -
It works for me. ( You can use http://demo.webwork.rochester.edu/webwork2/2019PerlConference101/ with profa/profa for login/password to view the library browser on my machine. I suspect that the connection to the images is not right for some reason and the fetch process is timing out. The remote fetch is not very good at handling errors gracefully. If you click on the images and use the tools in the browser you should be able to find out what path is being called to display the picture -- check to see if that seems right.
In reply to Michael Gage

Re: Library Browser Render Issues

by Steven Marshall -

Thank you for your reply. After reading your post I checked the path that says the file is missing. The file is getting created in the directory that it should (wwtmp/casit_test//gif/d8509050-0284-3be9-bdc7-20bd0ad49654___94ee93ce-b471-363d-b0b2-1a69fa5f51e4.png). I am also able to get to the file if I type in http:// instead of https:// using the browser. The site-config file has https://webwork.math.ou.edu, so I’m wondering if I’m missing some sort of proxy or redirect in the Apache config file.

In reply to Steven Marshall

Re: Library Browser Render Issues

by Steven Marshall -
I think I solved this, Thank you again for your help. I noticed that the document root inside of the default-ssl.conf is /var/www. When I look at our old webwork server, it was /var/www/html. Once I made that change, the images load fine.
In reply to Steven Marshall

Re: Library Browser Render Issues

by Alex Jordan -
It sounds like this issue has been resolved. We are experiencing something that sounds very similar, so I thought I'd post our situation.

We recently upgraded the OS. After doing that, sometimes images were not appearing and giving 404. I realized that they were "missing" when using "http" but "present" with "https". For example at the moment, one of these works and the other does not. The only difference is the "s".



We understand that the server is not set up correctly with its security certificates, and we think that fixing that will fix this, even if we don't understand why it only affect images. But the issue symptom was so similar to the one here that I thought it good to post.
In reply to Alex Jordan

Re: Library Browser Render Issues

by Steven Marshall -
Thanks for you post. One thing I should add is that we had to do is change the sites.config file file from https://webwork.math.ou.edu to https://localhost. I'm a little surprised that it works configured that way.