Service

class Service

A Service is, as the name indicates* a provider of services for other components.

It is declared in the services = {name: ServiceClass,} directive of Component and Module classes, to enable functionality like for example an http client, a search service, a logging facility, etc.

Directives:

  • bindings ({}):

    A dictionary containing the name and default value of attributes for the class which will also automatically add bound Observables

    The observables will have a _ (underscore) character appended.

    Setting the value of the attribute will trigger the observable and therefore any actions/subscriptions associated with it. Example:

    bindings = {‘myattr’: ‘myvalue’}

    will create:

    • An attribute myattr which defaults to myvalue
    • An observable myattr_

Attributes:

  • _parent: holds the instance of Component or Module in which the service was instantiated (use with care)
  • _module: holds the instance of Module in which the service (somewhere along the hierarchy) is. This will be the same as _parent if the service is declared in a Module (use with care)

Attribute Searching:

  • Subclasses of Service will access the attributes of self._parent if the attribute is not found as an instance/class attribute.