Example: validating coach data in a heritage human service in the desktop Process Designer (deprecated)

• name(String)
• salary(Decimal)
• creditLimit(Decimal)

1. From the library, create a general system service called CreditApplicationFormValidation.
2. On the Variables page of the service, add application(CreditCardApplication) as an input of the service.
   Important: The name and the type of the service input must match the name and type of the coach variable that contains the data that you want to validate.
   Add validate(CoachValidation) as an output of the service. The service must have one output only and it is of the CoachValidation type. The presence of this output indicates that the service is a validation service. In this case, the example uses the input to provide the data that the service validates.
   
3. Add a server script to the service diagram and connect the start and end nodes to the script.
4. In the implementation of the server script, add the following code to construct the CoachValidation business object:

   tw.local.validate = new tw.object.CoachValidation();
   
   if (tw.local.application.name == ""){
       tw.system.addCoachValidationError(tw.local.validate, "tw.local.application.name",
       "The name cannot be empty.");
   }
   if ( tw.local.application.salary <= 0){
       tw.system.addCoachValidationError(tw.local.validate, "tw.local.application.salary",
       "The salary must be above 0.");
   }
   if (tw.local.application.creditLimit > 2 * tw.local.application.salary){
       tw.system.addCoachValidationError(tw.local.validate, "tw.local.application.creditLimit",
       "The credit limit cannot be more than double the salary. " + "The maximum credit limit is $" + 
       2 * tw.local.application.salary + ".");
   }

   The tw.local.validate parameter is the CoachValidation business object that contains the validation information. The first string contains the full variable path to the data element with the problematic data. The second string is the message for the user. The message should identify what is wrong with the data or tell the user how to fix the problem.
   Important:

   • A coach can use only one validation service or server script to validate its data. However, more than one coach can use the same validation service or script.
   • If the data element being validated is not bound to a view, there is nowhere to display a validation error if one occurs.
   • If a view being validated contains rich text, the validation service must remove any formatting before validating the contents.

tw.system.coachValidation

1. Leave the Name field empty, type a 1 into the Salary field and into the Credit Limit field. Click Submit. The browser displays a message that the Name field cannot be empty.
2. Type a name into the Name field, and replace the 1 in the Salary field with a 0. Click Submit. The browser displays a message that the salary must be more than 0.
3. Replace the 0 in the Salary field with a 1. Replace the 1 in the Credit Limit field with a 3. Click Submit. The browser displays a message that the credit limit cannot be more than twice the salary.
4. Replace the 3 in the Credit Limit field with a 2. Click Submit. The human service now finishes because all three values are now valid.