languages file issue (likely not a bug as such)

[jondron]

Not sure this is actually a bug: it may be a feature of Elgg 1.9.7, but I have not seen it elsewhere so wonder whether it might be an implementation issue for this particular plugin (is there anything odd about how the language files are called?) ...

Symptoms...
On a Mac, if there is a .DS_Store file (usually is) this is sent before the language file, in advance of any headers, e.g.
[02-Nov-2015 17:59:38 Europe/Berlin] Exception #1446483578: exception 'SecurityException' with message 'Redirect could not be issued due to headers already being sent. Halting execution for security. Output started in file /Applications/MAMP/htdocs/elgg-1.9.7/mod/au_group_tag_menu/languages/.DS_Store at line 1. Search http://learn.elgg.org/ for more information.' in /Applications/MAMP/htdocs/elgg-1.9.7/engine/lib/elgglib.php:99

It can apparently be worked around by moving the plugin further down the list. Presumably, getting rid of .DS_Store would also work, so this is unlikely to be a concern in most production environments (except maybe when servers are Macs or other operating systems that leave hidden files lying around).

[beck24]

That's strange, I haven't encountered that. Then again I don't end up with .DS_Store files anywhere. I know they're a mac thing, and I use a Mac, but I never see them. Could be because I'm almost exclusively getting code via git or something. It's interesting that moving it down the plugin list changes the behaviour. Anyway, if this is an issue I doubt it's with this plugin. If anything it would be with core trying to do something with a dot-file in a languages directory

[jondron]

I've seen similar things in at least a couple of plugins: seems a core problem. Not at all clear why Elgg should try to run such things. I've tried configuring Apache to ignore .DS_Store but it seems Elgg bypasses that (must be using PHP's file access).

Macs hide it by default, but you can configure the Finder to show hidden files (a bit of a pain sometimes, but I find it essential). Removing .DS_Store via the command line does the trick, and it can be added to gitignore. Unfortunately, since El Capitan, it's not possible to safely intercept and prevent/redirect creation of it at operating system level, as used to be possible.

There's an app or two available to clean things up - FolderWasher is one - and it ought to be easy enough to create an automator script for it - but it's a hassle to remember and .DS_Store comes back as soon as you so much as look at a folder.