Did you check fms admin ? You should see the plugins there as well. I put the plugins in the extensions dir on the server :
Library/FileMaker Server/Database Server/Extensions
If you do a perform script on server it should be able to use the plugins. I do this for some stuff on iOS devices and FileMaker GO. Just remember you need to pass "context" as well. When performed on server, server doesn't know anything about which layout/record the user is on.
For WebDirect plugins need to be specially developed (small sentence in the WebDirect pdf), but I have avoided that route.
For starters, rrrichie is correct about the directory in which you should place the plugin. That's likely why you're having issues.
But let's cover some basics about plugins, what they are and how they work. Plugins extend the calculation engine. So your use of a plugin call inside a Set Variable script step is an example of a correct usage. You pass the plugin function inside any calculation. You could equally do it inside a field definition, a Conditional Formatting calculation, or anywhere else the calculation dialog is invoked. You don't "start" a plugin; it simply evaluates whenever it's called for when the calculation is evaluated.
Now, in order to use it on the server, you would need to verify that the calculation is evaluated on the server. So rrritchie is correct again: If you run a Perform Script On Server script step, it will evaluate on the server and use the plugin as installed there. (This Knowledge Base article may help you understand some of the differences: How Functions Evaluate Differently on the Host Versus the Client in FileMaker Pro | FileMaker )
When using Web Publishing, everything evaluates on the host (because there is no "client"). So as long as your plugin is installed properly, it should just work.
Rrrichie and Mike, thanks for your answers that clarified a lot of things.
In any case, my problem was the easier: the plugins have to be enabled on the FM Server and I didn't... This demonstrates that I'm a very newbie
It was enough to enable the plugin and... it works... of course, now I have a lot of other troubles but... it works!
Thanks a lot for your time
Welcome to the FileMaker platform and happy coding = creative puzzling :-)
I have been programming on this platform for a very long time and I still learn new "tricks" or "better" ways to do things.
If you are a true newbie, I suggest reading filemakerstandards.org while drinking coffee :-) You don't need to "implement" all that is there, but starting off with suggested naming guidelines for example will help down the road...
wonderful suggestion! Thanks a lot.
Actually, I'm no more an IT's newbie but if we talk about FM, yes, I'm so... FM is a new exciting challange and I'm enjoying myself with it