Incrementing System Properties integer value by multiple users causing duplicate values

[WatsonK]

Hello everyone!

I have a flow in flow designer that increments a value in system properties. This value should be readily available to users and every user should get a unique incremented value in a sequence. However, I am running into a problem where multiple users are accessing the same variable from system properties and are receiving duplicate values

This variable should increment every time a unique user accesses it, however when multiple users access it at the exact same time through a flow in flow designer, they receive the same value.

Does anyone have any ideas or experience regarding this issue, it would be greatly appreciated!

Thank you!

[Kieran Anson · Accepted solution]

Hi,

You'll need to create a custom flow action for this as you'll need to create a mutex. A mutex will ensure exclusive access to the resource and ensure each time it's accessed, a unique value is provided.

For example:

var generateCode = Class.create();
generateCode.prototype = {
    initialize: function() {
    },

	getCodeAndIncrement: function(){
		return new global.Mutex.enterCriticalSection('UNIQUE_NAME_FOR_MY_MUTEX' , this, getCode);
	},

	getCode: function(){
		//We use GlideRecord in order to leverage the mutex lock on the record
		var lastValue = new GlideRecord('sys_properties');
		lastValue.addQuery('name' , 'my.property.name');
		lastValue.setLimit(1);
		lastValue.setNoCount(true);
		lastValue.query();
		if(lastValue.next()){
			var codeToUse = lastValue.getValue('value');
			var newVaue = codeToUse ++;
			lastValue.setValue('value' ,  );
			lastValue.update();
			return codeToUse;
		}
	},

    type: 'generateCode'
};

[Kieran Anson]

What value does this add?

[joachimfmen]

It looks like a bot response, @Kieran Anson your answer really helped! Thank you!