WeBWorK Main Forum

Having problems with our Library Browser and emailing

Having problems with our Library Browser and emailing

by Alex Jordan -
Number of replies: 10
Hello,

We're experiencing difficulties with our installation and I was hoping someone might have insight where I can look to fix these things, what component I could update, or what file permissions I can change. We have an installation from the 2.7 LiveDVD. The people who actually did the installation are two degrees of separation from me, and it's hard to communicate with them about it, but I do have sysadmin privileges for the server. Thank you if you can help.
  • In the Library Browser, the button to add a problem to a target set does nothing. You click it, and nothing happens. I have seen what happens on a smoothly working server - the problem is added to the set and you are then alerted that the problem is in the target set.
  • When we use the email instructor button, after composing a message and clicking send, the message is not delivered and we get this error message:
    Failed to open the mailer: 5.7.1 : Relay access denied for ""PCC Administrator" " on host "mr.clackesd.k12.or.us"
  • Again in the Library Browser, clicking the re-randomize button is not working. Clicking it produces a screenful of errors:

    Errors: 500 Can't connect to webwork.pcc.edu:443 (certificate verify failed) at /opt/webwork/webwork2/lib/WebworkClient.pm line 159 End Errors

    WeBWorK error

    An error occured while processing your request. For help, please send mail to this site's webmaster (webmaster@localhost), including all of the following information as well as what what you were doing when the error occured.

    Mon Nov 18 19:40:07 2013

    Warning messages

    Error messages

    Can't call method "result" on an undefined value at /opt/webwork/webwork2/lib/WebworkClient.pm line 165.

    Call stack

    The information below can help locate the source of the problem.

    • in WebworkClient::xmlrpcCall called at line 274 of /opt/webwork/webwork2/lib/WeBWorK/ContentGenerator/instructorXMLHandler.pm
    • in WeBWorK::ContentGenerator::instructorXMLHandler::pre_header_initialize called at line 181 of /opt/webwork/webwork2/lib/WeBWorK/ContentGenerator.pm
    • in WeBWorK::ContentGenerator::go called at line 370 of /opt/webwork/webwork2/lib/WeBWorK.pm

    Request information

    Method POST
    URI /webwork2/instructorXMLHandler
    HTTP Headers
    User-Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:25.0) Gecko/20100101 Firefox/25.0
    Accept */*
    Connection keep-alive
    Referer https://webwork.pcc.edu/webwork2/LibraryDevelopment/instructor/setmaker/
    Content-Length 558
    Cache-Control no-cache
    Accept-Encoding gzip, deflate
    X-Requested-With XMLHttpRequest
    Content-Type application/x-www-form-urlencoded; charset=UTF-8
    Pragma no-cache
    Cookie WeBWorKCourseAuthen.LibraryDevelopment=alex.jordan%09ReEwvcY1e34AQcaOLi2x9WkxYZ037Ku0%091384832401; __utma=168888480.812643727.1383263297.1384742078.1384754084.61; __utmz=168888480.1384582081.52.9.utmcsr=google|utmccn=(organic)|utmcmd=organic|utmctr=(not%20provided); fos.web.server=vmpw4; fos.secure.web.server=vmpw4; badprotocol=7; __utmc=168888480; usidsec=pnI7ac0eeFiYgh+nEJglLg__; BANSSO=Z3PNZY2WYxPl0eOC65KqBbQ31JWkEYYWT4G67OMnBZ5pLc0m0EK04c12F9CyFbSwM=9=; d2lSessionVal=lNGXsCe1ZIpIhqgSsTuO9Cvvf; d2lSecureSessionVal=cbDyW1g9XfomiH5owimfgQRH9; usid=b5MZNnz56k6BVh/xRvPsTw__
    Accept-Language en-US,en;q=0.5
    Host webwork.pcc.edu
In reply to Alex Jordan

Re: Having problems with our Library Browser and emailing

by Alex Jordan -
Add one more Library Browser woe to my list: when browsing the National Problem Library and selecting a Subject, say Calculus - single variable, nothing updates. That is, the Chapter and Section dropdown menus do not update to their appropriate subcategories. They only allow for All Chapters and All Subjects.

It seems reasonable that my three Library Browser issues are all related. I think the emailing issue is something else for my sysadmin people to work out.

But here's a very odd thing. We are now running two servers, gearing up to roll them out this January. They are installed in two different locations by two different technology support teams (one by my school's IT people, and one by the IT people for a local school district that we partner with). We plan to use one for production and one for development/emergencies.

Before this morning, both were 2.7. The production server was the one experiencing these bugs that I have outlined, and the development server was fine. So I was pretty sure that the production server had not been installed as well as it could have. This morning I updated the development server to 2.8 following the steps on the wiki for updating through git. And now the development server is 2.8 and experiencing the exact same problems (except the emailing problem).

So now I don't think this is a local issue - can anyone with a new-ish installation of either 2.7 or 2.8 check that they don't have these same problems? They are the kind of things you wouldn't notice if you have been using set definition files lately. The symptoms are:
  • cannot browse the NPL by category
  • cannot use the "add" to target set button
  • using the rerandomize icon causes errors
In reply to Alex Jordan

Re: Having problems with our Library Browser and emailing

by Michael Gage -
Hi Alex,

I cannot confirm the behavior you are seeing using the most recent release/2.8 build.  (November 19).  I'm running on the hosted2.webwork.rochester.edu machine.

Add one more Library Browser woe to my list: when browsing the National Problem Library and selecting a Subject, say Calculus - single variable, nothing updates. That is, the Chapter and Section dropdown menus do not update to their appropriate subcategories. They only allow for All Chapters and All Subjects.


When browsing using LibraryBrowser (1, not 2 and not 3 ) the Chapter and Section dropdown menus update properly for me. Sometimes there is a second delay and the sign that they have updated is subtle.

This is javaScript -- if you view this in Safari, Chrome or Firefox and use one of the 
firebug or chrome webinspector tools can you see an error message of some kind?  Some file not loading perhaps?  Are there error messages in the apache error logs (something about refusing a connection)?  

Also have you run OPL-update recently?  It builds some files which cache the structure of the OPL directory.

Hope this helps.

Take care,

Mike 
In reply to Alex Jordan

Re: Having problems with our Library Browser and emailing

by Alex Jordan -
I see now there is a huge thread about this - will study it.
In reply to Alex Jordan

Re: Having problems with our Library Browser and emailing

by Michael Gage -
I suspect connectivity errors of some sort.  The javaScript is not able to connect properly back to the server to incrementally update the page.

Use the apache error log and javaScript inspectors in the browser to troubleshoot.  

Also report back once you resolve the situation, we don't currently have enough intelligent error messages reporting the difficulty.

Sometimes the difficulty has been incorrect specification of the webserver host site in sites.conf.  Firewalls and certificates might also cause silent difficulties with connecting back to the host.


In reply to Michael Gage

Re: Having problems with our Library Browser and emailing

by Alex Jordan -
I spoke too soon.

We have two servers at different locations and the production server is still causing problems. Taking the steps to isolate perl modules and get each one updated helped with our development server. But that is proving to be not enough with the production server.

Firebug reveals this error message when I click to activate the offending Library Browser tasks:
Errors:
500 Can't connect to webwork.pcc.edu:443 (certificate verify failed) at /opt/webwork/webwork2/lib/WebworkClient.pm line 158.
A bit later, there is another error message:

SyntaxError: JSON.parse: unexpected character

I can confirm that
$server_root_url = 'http://webwork.pcc.edu';
as it should be (I've also tried https, should that make a difference?)

The special authentication modules are commented out from localOverrides.conf.

Does that error message provide any insight?


In reply to Alex Jordan

Re: Having problems with our Library Browser and emailing

by Michael Gage -
Using https or http will make a difference.  It will also make a difference whether an https site has a legitimate certificate for the "secure" part of https.

It seems like the javaScript and webwork service are trying to communicate over https (that's port 443)  but there is a certificate that doesn't look kosher -- and the javaScript can't click "ignore and continue" the way a person would.

does this help?  I don't think it's a special authentication problem, it's the way that your apache server is set up to handle https requests on port 443.  Check the apache configurations in that region on the two machines and see what is different.

Hope this helps.

Take care,
Mike

In reply to Michael Gage

Re: Having problems with our Library Browser and emailing

by Alex Jordan -
We finally got this tackled. Here's a summary from our IT partner that explains what was happening.

...the intermediate CA certs were being cached on the client side and the javascript call was on the server side. I forgot to implement the intermediate CA certs into the certification chain, which wasn't a problem for most web browsers since they cache well known intermediate certs but the server calling back on itself couldn't resolve the entire certificate path.




In reply to Alex Jordan

Re: Having problems with our Library Browser and emailing

by Michael Gage -
Do you or your IT guys have a suggestion as to how the javaScript client/server AJAX connection can detect when this kind of unsatisfied certificate block is occurring? It would be nice to be able issue a specific warning about what is happening.  Your site is not the first one to have to guess there is a communication error and then try to figure out what could possibly be going wrong. :-)

-- Mike

In reply to Alex Jordan

Re: Having problems with our Library Browser and emailing

by Bentley Garrett -
Hi Alex:

We've been having the same issues with WeBWork2.8/ubuntu12.04 that you mention:

1)cannot browse the OPL by category
2)cannot use the "add" to target set button
3)using the rerandomize icon causes errors

(but email functions)

I noticed the summary from your IT support. May I ask exactly what was done to solve the problem? My IT person would be interested.

Any details would be appreciated.

Thanks,

-Bentley