The only thing I can think of which would cause a double submit would be if something was causing the form to be processed twice on the WordPress side. There is some code in Google Forms to detect processing the page multiple times (e.g. some SEO plugins basically process the whole page as part of the wp_header action) which could potentially result in two calls to wp_remote_post().
As I noted above, this situation was reported a while ago and I added some code to detect it however that doesn’t mean it couldn’t be happening again. Just last week a similar problem was being reported although it was on the form building side, the jQuery script which “tweaks” the form was being added twice and hence run twice due to some oddity in the theme.
Mike:
Since my above post, there’s been 10 submissions on 3 different forms.
The last one submitted 2 times. There was over 3 minutes between the duplicate submissions:
2014-11-03 03:01:55
2014-11-03 03:05:16
I’m not sure if there could be a server issue or what else might be causing this intermittantly. Possibly you could suggest steps to debug this, should it happen again.
Thanks for your reply and your efforts.
Neil
I cannot think of anything, other than possibly a spammer which does happen, that would cause this. I wish I could suggest something but other than the potential for code running twice as I outlined the other day, nothing comes to mind.
For the majority of the time everything’s been fine. Just these few intermittent bursts of 2-4 repeat submissions.
I’ll take a closer look at the server logs & other plugins. If anything turns up I’ll let you know.
Update: I’ve excluded our google forms pages from being cached. Since this was done there haven’t been any multiple form submissions.
So it looks like the cache plugin may have been the culprit.
Thanks for the update, that is a good thing to know should this issue come up again. Can you share which cache solution you were using?
This site uses WP Supercache. In “Accepted Filenames & Rejected URIs” I excluded the pages that have gforms.
I wasn’t able to prove this was the issue through proper debugging, just a hunch, so I’ll have to keep an eye on it.
Thanks again for the plugin,
Neil
