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Abstract hyperty

An abstract Hyperty is extended by all vertx Hyperties.

Use Verticle Configuration to set:

  • url hyperty url
  • identity Identity JSON compliant reTHINK Identity to be associated with the hyperty.
  • streams json object identifying streams to be published by the Hyperty. Example:
   {
     "id": "mystream",
     "url": "stream://mydomain.com/mystream"
   }

Persistence

DataObjects

Collection of Data Objects handled by the Hyperty:

{
  <hypertyUrl>: {
    <objectURL>: {
      userUrl: <URL>,
      type: <reporter|observer>
      }
  }
}

Headers

The Abstract Hyperty set the following Event Bus Message Headers (DeliveryOptions().addHeaders(header-name,header-value)):

  • from with value config().getString("url"),
  • identity with value config().getString("identity"),
  • type with value set by the Hyperty itself e.g. create

start

The Verticle start() where Vertx Event BUS handler at config.url address to receive messages targeting the Hyperty, is set. Received messages are processed by onMessage(msg).

send( address, message, reply ) function

Set from and identity headers before calling eb.send(..).

publish( address, message ) function

Set from and identity headers before calling eb.publish(..).

onMessage( msg ) function

Invitations (ie type = create and from has /subscription) are processed by the callback setup at onNotification.

onNotification( invitationMsg ) function

Process invitations to be an Observer or notifications that some existing DataObjectObserver was deleted. By default, invitations are accepted and the subscribe() function is called.

If a different logic is needed this function must be overwritten.

subscribe( address ) function

Send a subscription message towards address with a callback that sets the onChanges() as an handler at <address>/changes (ie eventBus.sendMessage( ..)).

A co

onChanges( changesMsg )

Function to process messages with changes on the observed Data Object subscribed with subscribe(). To be overwrite by classes extending the AbstractHyperty.

create(dataObjectUrl, observers, initialData ) function

Send the following message to all observers:

  type: "create",
  from: "dataObjectUrl/subscription",
  body: { source: <hypertyUrl>, schema: <catalogueURL>, value: <initialData> }

Some of these observers may be "Subscription Managers" that are running in P2P Vertx Protostubs, that locally create Data Object Reporters when this message is created.

It returns a Reporter object compliant with Syncher DataObjectReporter i.e. it adds a handler to dataObjectUrl/subscription that will fire onSubscription events.

storage management

When Hyperty handles information to be persisted it should have handlers at each config.streams to process incoming read messages that will return the queried data.

If the read message body does not contain any resource field, all persisted data is returned.