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hardcopy generation error

hardcopy generation error

by Eddie Fuller -
Number of replies: 4
Hi all,

I'm getting a hardcopy generation error from the HEAD code. When a set is selected the pdf is generated but this error appears:

WeBWorK error

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

Tue Aug 21 10:43:01 2007

Warning messages

Error messages

No display module found for path '/webwork2_course_files/Math128-F07A/tmp/hardcopy/Math128-F07A.ef.Aug20DailyHW.pdf/'. at /opt/webwork.23dev/webwork2/lib/WeBWorK.pm line 152.

Call stack

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

Request information

Method GET
URI /webwork2_course_files/Math128-F07A/tmp/hardcopy/Math128-F07A.ef.Aug20DailyHW.pdf
HTTP Headers
Keep-Alive 300
Accept-Charset ISO-8859-1,utf-8;q=0.7,*;q=0.7
User-Agent Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US; rv:1.8.1.6) Gecko/20070725 Firefox/2.0.0.6
Accept text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Connection keep-alive
Referer http://webwork.math.wvu.edu/Math128-F07A/hardcopy/
Accept-Encoding gzip,deflate
Accept-Language en-us,en;q=0.5
Host webwork.math.wvu.edu


I have a feeling that this is not a bug but some configuration problem that I have. My install directories are little non-standard (i.e. everything is in /opt/webwork.23dev/) but I'm 99% sure everything in global.conf is correct since everything else works. The trailing slash on the path is a little odd, though. Any insight is appreciated.

-Eddie
In reply to Eddie Fuller

Re: hardcopy generation error

by Blake Thornton -
This sounds similar to the problem we had with apache aliases. The apache.conf file probably has some aliases that are a regular expression. I had to hard code the needed expressions. So, I had to add this line (one line for each course):
Alias /webwork2_course_files/Course_Name /opt/webwork2/courses/Course_Name/html
to the apache.conf file and restart apache. We don't run many courses so it isn't such a big deal but I would certainly prefer that it just worked right.
In reply to Blake Thornton

Re: hardcopy generation error

by Eddie Fuller -
I tried hardcoding the alias but no joy. I also upgraded my production installation to WW2.4 with all the standard settings and get

WeBWorK error

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

Tue Aug 21 14:50:03 2007

Warning messages

Error messages

No display module found for path '/webwork2_course_files/Math128-F07A/tmp/hardcopy/Math128-F07A.ef.Aug20DailyHW.pdf/'. at /opt/webwork/webwork2/lib/WeBWorK.pm line 152.

Call stack

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

Request information

Method GET
URI /webwork2_course_files/Math128-F07A/tmp/hardcopy/Math128-F07A.ef.Aug20DailyHW.pdf
HTTP Headers
Keep-Alive 300
Accept-Charset ISO-8859-1,utf-8;q=0.7,*;q=0.7
User-Agent Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US; rv:1.8.1.6) Gecko/20070725 Firefox/2.0.0.6
Accept text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Connection keep-alive
Referer http://webwork.math.wvu.edu/Math128-F07A/hardcopy/
Accept-Encoding gzip,deflate
Accept-Language en-us,en;q=0.5
Host

so now I'm more inclined to suspect a bug.

-Eddie
In reply to Eddie Fuller

Re: hardcopy generation error

by Eddie Fuller -
It turns out this is related to my having put webwork at the root of my server, e.g. using http://webwork.math.wvu.edu/$COURSE$ as my class url instead of /webwork2/$COURSE$ as is the default. I changed the line in global.conf to

webwork_url = "";

to get this based on the comments in that file. After traffic died down this evening I changed this back and hardcopies work again.

So I'll rephrase my question. What else should I change to get this to work? The AliasMatch stanza in webwork.apache-config? Any suggestions? or should I just go back to the default /webwork2 config? I've already published the urls to the students in several classes.

-Eddie
In reply to Eddie Fuller

Re: hardcopy generation error

by Sam Hathaway -
Hi Eddie,

Check this, but I think you can use "/" rather than "" to put WeBWorK on the root in 2.4. The 2.4.0 versions of webwork.apache[2]-config.dist no longer suggest "", and I'm pretty sure the changes necessary to use "/" made it into this release.

Sorry for the vagueness, but I'm in a rush at the moment. Hope this helps.
-sam