Webcore Child return parameters

[fdelima]

Hi There,

hoping someone can help with this.. I've looked everywhere for documentation and cant find any.

Issue: I want to return a parameter from a Child Piston and I dont know how.

so I have : Execute Piston "Child Piston" with arguments (to-child, from-child);

My child piston uses "to-child' via the args but how do i get "from-child" to be be sent and used by the Parent (calling) Piston ?

Thanks in advance

[nh.schottfam]

I don't know that you can return parameters on a call. You may need to use global variables, or have the piston that receives the call to make a call back.

See:

webCoRE for Hubitat Updates

Additional details on how things work: webCoRE Operations Your pistons execute locally and if the webCoRE servers/internet are down, pistons keep working (unless the piston is using one of the below mentioned webCoRE server functions). It is possible to run the webCoRE [dashboard] server locally (see below) Your piston is stored in HE hub (inside the piston child application). When in the webCoRE dashboard and you want to edit a piston, the webCoRE dashboard requests the code from HE, and …

• If you need a larger application, you can use multiple pistons, and have a main piston call the sub-pistons. Again, leave the wait = true on when performing "execute piston"
  • do note:
    • to pass data to a piston, you can use arguments on the piston call, or global variables.
    • to get data returned from a piston execution, global variables are often the best choice.
    • note that a piston can subscribe to a global variable change. (globalvariable changes). This design paradigm can make it easy to not worry about the loading comments below.
      • global variables are "loaded" when a piston starts, and saved when a piston exits, so if:
        • Piston A calls piston B, and B modifies a global variable, piston A will not see the change until the next time piston A executes.
        • Piston A modifies a variable and calls piston B, since A has not exited yet, the change to the global variable is likely not to be seen by B until B runs again after A has exited (and saved changes)

and

Some webCoRE Basics for writing pistons - Using variables

This is another example of writing a piston, utilizing variables. When you create a piston, the webCoRE IDE may not initially show the variables section: [Screen Shot 2022-01-26 at 12.40.49 AM] To see the variables section when in edit mode the ‘Show Variables’ icon: [Screen Shot 2022-01-26 at 12.42.12 AM] Now you can add new local variables: [Screen Shot 2022-01-26 at 12.42.48 AM] To define a variable select the + add a new variable [Screen Shot 2022-01-26 at 12.44.05 AM] You must …

[fdelima]

Thanks extremely helpful and saved me endless hours of frustration....