[LON-CAPA-admin] Images not showing up in student view for some questions
Stuart Raeburn
raeburn at msu.edu
Wed Oct 30 10:25:30 EDT 2013
Hi,
> is it just the space between the "/" and the ">" that's causing it
> to be malformed?
Yes.
(a) Malformed: <allow src="something"/ > (i.e., ... quote slash space endtag)
(b) Well-formed: <allow src="something" /> (i.e., ... quote space
slash endtag)
In (a) the parser interprets this as text: <allow src="something"/ >,
whereas in (b) the parser interprets this as a start allow tag
containing a src attribute with a value of: something.
Stuart Raeburn
LON-CAPA Academic Consortium
> Thanks for sorting this out, Stuart. I was really perplexed.
>
> I honestly didn't see that the <allow> tag was malformed... is it
> just the space between the "/" and the ">" that's causing it to be
> malformed?
>
> Thank you again,
>
> Cheers,
> Michael
> On Oct 29, 2013, at 10:30 PM, Stuart Raeburn <raeburn at msu.edu> wrote:
>
>> Hi,
>>
>>>> Just checked again. I must have been mistaken. I do find that
>>>> image. Same behaviour as you observed. I.e. Course coord can see
>>>> the image in the problem but a student in a course cannot.
>>
>> A Course Coordinator will be able to see a published image used in a
>> problem, in cases where the the allow tag is malformed, because a CC
>> is permitted to display any resources published with a system-wide
>> right of use.
>>
>> Students, however, will not see the image in cases where the allow tag
>> is malformed.
>>
>> That is what happened in this case in:
>> /res/vcu/s2bdedmo/SOL05_HS_Chemistry/SOL05_HSChem_19_Acids.problem
>>
>> If the current allow tag in this problem:
>>
>> <allow
>> src="/res/vcu/s2bdedmo/SOL05_HS_Chemistry/images/SOLHS05_Chemistry_19_MixingSolutionsTable.JPG"/
>>>
>>
>> is replaced with a well-formed self-closing allow tag:
>>
>> <allow
>> src="/res/vcu/s2bdedmo/SOL05_HS_Chemistry/images/SOLHS05_Chemistry_19_MixingSolutionsTable.JPG"
>> />
>>
>> then students will also be able to see the image.
>>
>> It seems likely that other resources published by this particular
>> author may also have similarly malformed, manually entered <allow> tags.
>>
>> Anyway, I have updated the bug filed for this issue:
>> http://bugs.loncapa.org/show_bug.cgi?id=6683
>>
>> to request a change to LON-CAPA to include correction of malformed
>> <allow> tags during publication of a resource.
>>
>> I have also sent an e-mail to the resource author.
>>
>>
>> Stuart Raeburn
>> LON-CAPA Academic Consortium
>>
>>
>> Quoting loncapa_admin <loncapa_admin at johnabbott.qc.ca>:
>>
>>> Thanks again, Ray.
>>>
>>> At least I know it's not some local phenomenon. Always worried that
>>> I've muffed a config file or two.
>>>
>>> Digging through the black hole that is my admin notes, another
>>> teacher had noticed a similar behaviour with some of her
>>> self-authored problems. Didn't make the connection at first,
>>> thought this was either a problem with a poorly-written or published
>>> problem. Or something about our local config. Had put that into
>>> the "look at this over the Christmas break" pile. Going to look at
>>> the bugzilla to see if there's any related tickets.
>>>
>>> Thanks again,
>>>
>>> Cheers,
>>> Michael
>>>
>>> On 2013-10-18, at 10:37 AM, Raymond Batchelor <batchelo at sfu.ca> wrote:
>>>
>>>> Just checked again. I must have been mistaken. I do find that
>>>> image. Same behaviour as you observed. I.e. Course coord can see
>>>> the image in the problem but a student in a course cannot.
>>>>
>>>> Student sees large square blank space where image should be.
>>>>
>>>> ----- Original Message -----
>>>> From: Michael Dugdale <michael.dugdale at johnabbott.qc.ca>
>>>> To: list about administration and system updating
>>>> <lon-capa-admin at mail.lon-capa.org>
>>>> Sent: Fri, 18 Oct 2013 05:57:37 -0700 (PDT)
>>>> Subject: Re: [LON-CAPA-admin] Images not showing up
>>>> in student view for some questions
>>>>
>>>> Thanks again Mark,
>>>>
>>>> We're running 1 library and 2 access servers --- the behaviour is
>>>> repeatable on all of them. Our access servers are a little bit of
>>>> an unusual configuration (PPC64) so that's the first thing I
>>>> checked: it's happening on our stock RedHat 5 X86_64 library server
>>>> too.
>>>>
>>>> I don't think it's a replication problem: the file's on each of the
>>>> servers, with modification dates that vary slightly (I'm
>>>> interpreting that as an indicator of when the resource was
>>>> replicated).
>>>>
>>>> Hmm... interesting observation about the version #... hadn't
>>>> noticed that. It does seem strange.
>>>>
>>>> On 2013-10-17, at 11:11 PM, Mark Lucas <lucasm at ohio.edu> wrote:
>>>>
>>>>> Is it sometimes taking a while for things to get replicated over
>>>>> to the server if it's
>>>>> not already cached? How many different servers do your students
>>>>> log in on, just one?
>>>>>
>>>>> The only other strange thing I see is Version: -1 for the image.
>>>>> Is that a stray hyphen or really minus one? What does version -1 mean?
>>>>>
>>>>> Later,
>>>>> Mark
>>>>>
>>>>> On Oct 17, 2013, at 9:28 PM, Michael Dugdale wrote:
>>>>>
>>>>>> Thanks for the observation ray.
>>>>>>
>>>>>>
>>>>>> It's strange that you can't see it. We're not vcu so we're only
>>>>>> seeing what's been published system-wide. As course coordinator,
>>>>>> it's visible. Only student roles are being denied access.
>>>>>>
>>>>>> Browsing to the image file, the meta-data page (copy/pasted
>>>>>> below) has the line "Copyright/Distribution: System wide - can be
>>>>>> used for any courses system wide".
>>>>>>
>>>>>> Strange that you're not able to see it out west.
>>>>>>
>>>>>> ---------------------------
>>>>>>
>>>>>> Metadata
>>>>>>
>>>>>> Untitled Resource
>>>>>> /res/vcu/s2bdedmo/SOL05_HS_Chemistry/images/SOLHS05_Chemistry_19_MixingSolutionsTable.JPG
>>>>>> Version: -1
>>>>>>
>>>>>> Title:
>>>>>> Author(s): Josephus Ferguson
>>>>>> Subject:
>>>>>> Keyword(s):
>>>>>> Notes:
>>>>>> Abstract:
>>>>>> Lowest Grade Level: Not specified
>>>>>> Highest Grade Level: Not specified
>>>>>> Standards:
>>>>>> MIME Type: <jpg.gif> JPEG Image Document
>>>>>> Language: Not set -
>>>>>> Creation Date: Mon Jun 2 09:37:25 pm 2008 (EDT)
>>>>>> Last Revision Date: Mon Jun 2 09:37:25 pm 2008 (EDT)
>>>>>> Publisher/Owner: Bartlett zzEdmonds [s2bdedmo:vcu]
>>>>>> Copyright/Distribution: System wide - can be used for any courses
>>>>>> system wide
>>>>>> Custom Distribution File:
>>>>>> Source Available: Closed - XML source is closed to everyone
>>>>>> Source Custom Distribution File:
>>>>>> Obsolete:
>>>>>> Suggested Replacement for Obsolete File:
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 2013-10-17, at 9:08 PM, Raymond Batchelor <batchelo at sfu.ca> wrote:
>>>>>>
>>>>>>> Well, that particular image is not published system wide,
>>>>>>> because it does not appear on this side of the continent.
>>>>>>> :-)
>>>>>>> Perhaps the author (s2bdedmo:vcu) did not allow Sytemwide
>>>>>>> Copyright/Diustribution or did not yet publish it. Better try to
>>>>>>> contact them.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> ----- Original Message -----
>>>>>>> From: "Michael Dugdale" <michael.dugdale at johnabbott.qc.ca>
>>>>>>> To: "list about administration and system updating"
>>>>>>> <lon-capa-admin at mail.lon-capa.org>
>>>>>>> Sent: Thursday, 17 October, 2013 17:52:40
>>>>>>> Subject: [LON-CAPA-admin] Images not showing up in student view
>>>>>>> for some questions
>>>>>>>
>>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>>
>>>>>>> Looking for some help here. A chemistry teacher has reported a
>>>>>>> number of cases where the images associated with a problem don't
>>>>>>> show up for students. It loads fine for course coordinators.
>>>>>>> It's just the images that are included in the problem that are
>>>>>>> not showing up; the rest of the problem loads fine.
>>>>>>>
>>>>>>>
>>>>>>> Trying to open just the image in a new tab (as student) gives
>>>>>>> the following error:
>>>>>>>
>>>>>>>
>>>>>>> -----------------------------
>>>>>>> LON-CAPA Access Control
>>>>>>>
>>>>>>>
>>>>>>> Access : Browse resources
>>>>>>> Resource:
>>>>>>> /res/vcu/s2bdedmo/SOL05_HS_Chemistry/images/SOLHS05_Chemistry_19_MixingSolutionsTable.JPG
>>>>>>> Action : Access Denied
>>>>>>> Sorry ...
>>>>>>> This action is currently not authorized.
>>>>>>> ------------------------------
>>>>>>>
>>>>>>>
>>>>>>> I've looked in the file system, and the files are there,
>>>>>>> owner/group are www:www with permissions -rw-r--r--
>>>>>>>
>>>>>>>
>>>>>>> As far as Apache logs go, I see many remarks of the form:
>>>>>>>
>>>>>>>
>>>>>>> [Thu Oct 17 20:23:36 2013] [error] access to
>>>>>>> /res/vcu/s2bdedmo/SOL05_HS_Chemistry/images/SOLHS05_Chemistry_19_MixingSolutionsTable.JPG failed for 74.57.249.17, reason: Access Denied for michaeldugdale domain johnabbott
>>>>>>> access
>>>>>>> bre
>>>>>>>
>>>>>>>
>>>>>>> Trying to get a sense of what's going on, I checked the problem
>>>>>>> file on the server's file system and it does, indeed have the line
>>>>>>> <allow
>>>>>>> src="/res/vcu/s2bdedmo/SOL05_HS_Chemistry/images/SOLHS05_Chemistry_19_MixingSolutionsTable.JPG"/
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> And I've double-checked that SELINUX is disabled...
>>>>>>>
>>>>>>>
>>>>>>> I'm fresh out of ideas about where to look next. Does anyone
>>>>>>> have any thoughts on where I should look?
>>>>>>>
>>>>>>>
>>>>>>> Thanks in advance,
>>>>>>>
>>>>>>>
>>>>>>> Michael Dugdale
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Michael Dugdale
>>>>>>> Co-chair (Scheduling)
>>>>>>> Department of Physics
>>>>>>> John Abbott College
>>>>>>> 21,275 Lakeshore Road
>>>>>>> Ste. Anne de Bellevue, Québec
>>>>>>> H9X 3L9, Canada
>>>>>>> (514) 457-6610 Ext. 5888
>>>>>>> michael.dugdale at johnabbott.qc.ca
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> LON-CAPA-admin mailing list
>>>>>>> LON-CAPA-admin at mail.lon-capa.org
>>>>>>> http://mail.lon-capa.org/mailman/listinfo/lon-capa-admin
>>>>>>>
>>>>>>> --
>>>>>>> Raymond J. Batchelor, PhD.
>>>>>>> Department of Chemistry
>>>>>>> Simon Fraser University
>>>>>>>
>>>>>>> Phone: 778-782-5635
>>>>>>> _______________________________________________
>>>>>>> LON-CAPA-admin mailing list
>>>>>>> LON-CAPA-admin at mail.lon-capa.org
>>>>>>> http://mail.lon-capa.org/mailman/listinfo/lon-capa-admin
>>>>>>
>>>>>> _______________________________________________
>>>>>> LON-CAPA-admin mailing list
>>>>>> LON-CAPA-admin at mail.lon-capa.org
>>>>>> http://mail.lon-capa.org/mailman/listinfo/lon-capa-admin
>>>>>
>>>>> --
>>>>> Mark Lucas
>>>>> email: lucasm at ohiou.edu
>>>>> 252D Clippinger Lab
>>>>> phone: (740)597-2984
>>>>> Department of Physics and Astronomy fax: (740)593-0433
>>>>> Ohio University
>>>>> Athens, OH 45701
>>>>>
>>>>> _______________________________________________
>>>>> LON-CAPA-admin mailing list
>>>>> LON-CAPA-admin at mail.lon-capa.org
>>>>> http://mail.lon-capa.org/mailman/listinfo/lon-capa-admin
>>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> LON-CAPA-admin mailing list
>>>> LON-CAPA-admin at mail.lon-capa.org
>>>> http://mail.lon-capa.org/mailman/listinfo/lon-capa-admin
>>>>
>>>> --
>>>> Raymond J. Batchelor, PhD.
>>>> Department of Chemistry
>>>> Simon Fraser University
>>>>
>>>> Phone: 778-782-5635
>>
>>
>> _______________________________________________
>> LON-CAPA-admin mailing list
>> LON-CAPA-admin at mail.lon-capa.org
>> http://mail.lon-capa.org/mailman/listinfo/lon-capa-admin
>>
>
>
>
> Michael Dugdale
> Co-chair (Scheduling)
> Department of Physics
> John Abbott College
> 21,275 Lakeshore Road
> Ste. Anne de Bellevue, Québec
> H9X 3L9, Canada
> (514) 457-6610 Ext. 5888
> michael.dugdale at johnabbott.qc.ca
>
>
>
>
>
>
> _______________________________________________
> LON-CAPA-admin mailing list
> LON-CAPA-admin at mail.lon-capa.org
> http://mail.lon-capa.org/mailman/listinfo/lon-capa-admin
>
More information about the LON-CAPA-admin
mailing list