Angular JS observe on directive attribute

Question

How can angular js watch attributes on custom directive in order to accept angular values to be bind

Here is what I have so far:

Answer 1

From https://docs.angularjs.org/api/ng/type/$compile.directive.Attributes:

all of these are treated as equivalent in Angular:

So the attribute data-value normalizes to value

So, this is what you want:

attrs.$observe('value', function(val) {