Using return in a command script

Bob Sneidar bobsneidar at iotecdigital.com
Wed Oct 26 19:19:46 EDT 2016


I'll try to enumerate the process. I have an openStack handler in the card script of the mainstack. In this handler I initialize the app. First I insert my validations, utilities and front scripts into the message hierarchy. Then I attempt to register sqlyoga. If that succeeds, I go to a card called database setup. 

This also has an openCard handler which attempts to connect to the registered database. If it is successful, I want to return true to the openCard handler on the first card, otherwise I want to return false. The reason is that the next step involves a login stack which queries the database for users and allows the user to login. I also query for settings. I cannot proceed until I know I have a good database connection. 

I know it sounds convoluted, but I have some portable cards and stacks which function simply by including them in the mainstack, and then going to the card or stack. All of these cards/stacks are triggered by openCard/openStack handlers. I don't want the calling stack to actually call a handler on the target stacks. I want developers to simply go to those cards or stacks, which will populate properties of the mainstack with data that will be used later. 

For example, the login stack will set properties in the mainstack called loginid, username and fullname which are used later by the settings card and every record added or updated will get the fullname in the updateby column, which every table I have has. 

Now if I cannot connect to the database, then I haven't retrieved the settings and I haven't logged in, so I need to set some properties of the mainstack in the openCard handler of the mainstack so that when I do connect I can check those and force a login and settings update. 

As I mentioned in a prior email, it's no big deal because I just work around it by setting properties instead of returning a value. It's just a gotcha to return a value in a built-in message handler if those handlers always set the result to empty. 

Bob S


> On Oct 26, 2016, at 15:17 , Monte Goulding <monte at appisle.net> wrote:
> 
> 
>> On 27 Oct. 2016, at 9:07 am, Bob Sneidar <bobsneidar at iotecdigital.com> wrote:
>> 
>> I return a value at the end of an openCard handler
> 
> What are you returning it to? openCard is sent by the engine… or are you calling it yourself? 
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