[wp-hackers] Best way to kick off actual work from plugin settings page?

[Dougal Campbell]

On Jul 12 2010 3:04 AM, Matt Jacob wrote:
> I'm using the settings API for my plugin's custom settings page, and 
> it's working pretty well. Sometimes, though, I want to perform an 
> action based on a submitted value instead of just saving the value 
> back to the DB. Where's the best place to intercept the form 
> submission and do some actual work?
>
> I have two possibilities in my mind:
>
> 1. Hook into the admin_init action, since this should come before the 
> $_POST array gets wiped out. I can determine if a specific submit 
> button was used, if a certain checkbox was checked, etc. and then do 
> some work based on those criteria.
>
> 2. Use the validation callback in register_setting() to check the 
> submitted fields for what I want, do some work, and then return only 
> the options I actually want to be persistent. (I'm using a single 
> array for all of my options, so it's easy to leave some options out.)
>
> Option #2 seems more elegant, but it's kind of overloading the purpose 
> of the callback.
>
> Just for reference, the kind of "work" I'm talking about doing is 
> regenerating a secret token or importing existing records to custom 
> posts during an upgrade.
>

I've used both methods before. Which I choose seems to depend on context 
and complexity of the tasks I'm performing. Quick, simple things can 
often slip into the settings validation callback. For more complex 
functions I might catch it on admin_init. Or sometimes I'll use a hybrid 
method -- detection in the validation callback, setting a transient 
flag, which I then look for later (perhaps for a cron schedule).


-- 
Dougal Campbell <dougal at gunters.org>
http://dougal.gunters.org/
http://twitter.com/dougal
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