Statifier.Send.Event (Statifier v2.6.0)

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Builds the event a <send> delivers, from the send effect the core produced (ADR-0069 decision 4). Pure: no process, no clock, no lookup.

build/3 is the one construction site. Statifier.Session calls it for every event a built-in <send> delivers to an external queue, and hands its result to a registered processor (Statifier.Send.Processor) for a send of a registered type. A host that drives Statifier.Interpreter with no session reads the effect off the core and calls it itself.

What it stamps, per spec 5.10.1 and C.1:

  • name is the send's event, and data its resolved payload;
  • sendid is the send id only when the author wrote id or idlocation on the <send> (the effect's id_from_author?), and nil otherwise - C.1's empty-sendid rule;
  • caller_context is a delayed send's opaque host term (ADR-0063), and nil for an immediate send, which carries none;
  • origin defaults to the sender's #_scxml_<sessionid> location and origintype to the SCXML Event I/O Processor URI.

A processor with its own reply address passes :origin and :origintype, so a receiver that answers "via the Event I/O Processor specified in 'origintype'" (5.10.1) reaches that processor rather than the sender's session.

Why the default origintype is the URI

C.1's prose says the field MUST have the value "scxml". The W3C conformance suite requires the URI instead: test198 sends with no type attribute and asserts _event.origintype == 'http://www.w3.org/TR/scxml/#SCXMLEventProcessor', test352 asserts the same for an explicitly typed send, and test253 accepts either spelling. No test in the corpus requires "scxml". The default follows the suite. It is the URI whatever type the author wrote, so <send type="scxml"> also reports the URI where 5.10.1's "equivalent to the 'type' field on the <send> element" would echo "scxml"; test253 accepts both and nothing else covers it.

Summary

Types

option()

build/3's options: :origin (a URI string) and :origintype (a type string), each replacing its default when given.

Functions

build(send, session_id, opts \\ [])

The %Statifier.Event{} that send delivers, sent by the session session_id (spec 5.10's _sessionid). See the moduledoc for each field.

Types

option()

@type option() :: {:origin, String.t()} | {:origintype, String.t()}

build/3's options: :origin (a URI string) and :origintype (a type string), each replacing its default when given.

Functions

build(send, session_id, opts \\ [])

@spec build(
  send :: Statifier.Effect.Send.t() | Statifier.Effect.SendDelayed.t(),
  session_id :: String.t(),
  opts :: [option()]
) :: Statifier.Event.t()

The %Statifier.Event{} that send delivers, sent by the session session_id (spec 5.10's _sessionid). See the moduledoc for each field.

Examples

iex> send = %Statifier.Effect.Send{
...>   event: "impression.joined",
...>   data: %{"impression_id" => "imp-1"},
...>   send_id: "send_1",
...>   macrostep: 0,
...>   microstep: 0,
...>   round: 0
...> }
iex> event = Statifier.Send.Event.build(send, "sess_1")
iex> {event.name, event.data, event.sendid, event.origin}
{"impression.joined", %{"impression_id" => "imp-1"}, nil, "#_scxml_sess_1"}
iex> event = Statifier.Send.Event.build(send, "sess_1", origin: "myapp:reply/7", origintype: "myapp:execution")
iex> {event.origin, event.origintype}
{"myapp:reply/7", "myapp:execution"}