Fatal error trying to use an image in a forum topic

[Aaron Wells]

I noticed this one while using 16.04dev.

To replicate:

1. Create a group
2. In the group, navigate to the default forum and post a topic
3. In the TinyMCE editor for the topic, use the image button.
4. The image button will pop up the TinyMCE image utility, with the Mahara uploader/selector. Use this to upload an image into your file storage and put the image into the TinyMCE text area.
5. Save the topic.

Expected result: The topic is saved, and you can see it with the image in place.
Actual result: Mahara loads a fatal error page with this error:

( ! ) Fatal error: Call to undefined function artefact_instance_from_id() in /home/aaronw/www/mahara/htdocs/lib/embeddedimage.php on line 59
Call Stack
# Time Memory Function Location
1 0.0006 326080 {main}( ) ../edittopic.php:0
2 0.0961 10553960 pieform( ) ../edittopic.php:173
3 0.0984 10858176 Pieform::process( ) ../mahara.php:4438
4 0.0984 10860696 Pieform->__construct( ) ../pieform.php:161
5 0.6325 11054376 call_user_func_array ( ) ../pieform.php:540
6 0.6325 11054720 addtopic_submit( ) ../pieform.php:540
7 0.6997 11082160 EmbeddedImage::prepare_embedded_images( ) ../edittopic.php:220

[Aaron Wells (u-aaronw)]

I ran a quick test and verified that this problem is *not* present in 15.10.

[Aaron Wells (u-aaronw)]

Git bisect traces the regression to this commit: https://reviews.mahara.org/#/c/5818/

There's nothing obvious in there that would cause a problem. My best guess is that the additional safe_require() call is paradoxically causing the lib/embeddedimage.php file to not get loaded, somehow.

[Mahara Bot (dev-mahara)]

Patch for "master" branch: https://reviews.mahara.org/5994

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/5994
Committed: https://git.mahara.org/mahara/mahara/commit/3f4b4b7f9cbda6c63090843605591285492bc4fe
Submitter: Robert Lyon (<email address hidden>)
Branch: master

commit 3f4b4b7f9cbda6c63090843605591285492bc4fe
Author: Aaron Wells <email address hidden>
Date: Tue Feb 2 13:05:44 2016 +1300

Prevent crashes when embedding images

Bug 1540667: Prior to commit c432903, we were loading htdocs/artefact/internal/lib.php
on *every* page load, via the login auth method's code that checked for missing
internal artefact files. This call meant that we also loaded artefact/lib.php on
every page load.

Removing that for performance reasons, caused some calls to embeddedimages.php to fail,
when they were on pages that aren't otherwise requiring artefact/lib.php.

behatnotneeded: Can't use the image embedder from Behat

Change-Id: Ibcdbd17d289f2b4614c28ad522173286acc9bc27