Reader

A reader is used by the handler during the execution (Handler.runAction) to query the Input and Session information that is going be used during the execution of the action.

In case of new implements it's expected to implement the Reader._perform.

When a value is found for an input it's decoded using Input.parseValue where each input implementation has its own way of parsing the serialized data, to find out about how a value is serialized for an specific input type you could simply set an arbitrary value to an input then query it back through Input.serializeValue. The reference bellow shows the basic serialization for the inputs blundled with Mebo:

Options: Custom options can be assigned to readers (Reader.setOption). They are passed from the handler to the reader during the handler's execution (Handler.runAction).

const myHandler = Mebo.Handler.create('someHandler');

// setting reading options
myHandler.runAction('myAction', {
 someOption: 10,
});

When an action is executed through a handler it can define options via the Metadata support. Detailed information about that can be found at Metadata:

@Mebo.register('myAction')
class MyAction extends Mebo.Action{
   constructor(){
     super();

     // defining a custom reading option
     this.setMeta('$myOption', {
       someOption: 10,
     });

     // ...
   }
}

Hiding inputs from readers: A reader only sees inputs that are capable of serialization (Input.isSerializable) or visible inputs. Therefore, any input assigned with the property hidden is not visible by readers, for instance:

class Example extends Mebo.Action{
  constructor(){
    super();
    this.createInput('readerCantSeeMe: numeric', {hidden: true});
    this.createInput('readerSeeMe: numeric');
  }
}