From: "Peter Droogmans" Peter@attiks.com To: development@drupal.org, support@drupal.org Sent: Tuesday, November 27, 2012 12:38:57 AM Subject: Re: [development] File upload and convert
<SNIP>
You could do it using a custom file field widget as well, just extend the current one ( have a look at the image field widget, it extends the file widget )
Cheers,
Peter
Hi Peter,
Thanks very much. This one tiny bit of advice is exactly the assistance I needed. Give yourself a raise.
I was trying to understand if "file" needs to know about "image" for the extension, or if "image" can simply extend without the knowledge or cooperation of "file". This interaction is pretty central to Drupal (Earnie!) and I have not yet found the Rosetta stone. W hile investigating this I discovered that there are upload validation functions. "Upload validation" is precisely what I want to do: provisionally accept a file for upload, perform some operation and continue or abort, depending on the outcome of the operation. Further, I can enable/disable a particular conversion with a checkbox in the standard dialog. It looks to me, with my untrained and novice enthusiasm, that almost everything is already in place. This is beginning to look like a contributed module "Conversions", which would please me greatly, if I can learn enough about how this works to do it.
So, the natural question is, is "upload validations" an extensible set? Where can I investigate this more fully?
Thanks for the help,
Chris.