chainable events

Author: matt-beanland

lib/diffo/provider/components/characteristic.ex

@@ -149,6 +149,12 @@ defmodule Diffo.Provider.Characteristic do
     end
   end
 
+  validations do
+    validate present([:instance_id, :feature_id, :relationship_id], at_most: 1) do
+      message "characteristic must be related to at most one of an instance, feature or relationship"
+    end
+  end
+
   preparations do
     prepare build(sort: [name: :asc])
   end

lib/diffo/provider/components/event.ex

@@ -23,13 +23,15 @@ defmodule Diffo.Provider.Event do
 
   code_interface do
     define :create
+    define :chain
     define :destroy
   end
 
   neo4j do
     relate [
-      {:instance, :FIRED, :incoming, :Instance}
-      # {:earlier_event, :AFTER, :outgoing, :Event}
+      {:instance, :FIRED, :incoming, :Instance},
+      {:head, :AFTER, :incoming, :Event},
+      {:tail, :AFTER, :outgoing, :Event}
     ]
   end
 
@@ -58,13 +60,21 @@ defmodule Diffo.Provider.Event do
       description "creates an event, fired by an instance"
       accept [:type]
       argument :instance_id, :uuid
-      # argument :earlier_event_id, :uuid
 
-      change manage_relationship(:instance_id, :instance, type: :append_and_remove)
-      # change manage_relationship(:earlier_event_id, :earlier_event, type: :append_and_remove)
+      # ideally capture the id of the event last fired by the instance, if any, and call before on it to bump it down the chain
+      change manage_relationship(:instance_id, :instance, type: :append)
       change load [:instance_type, :instance]
     end
 
+    update :chain do
+      description "chains the event from the head event"
+      primary? true
+      argument :head_id, :uuid
+      argument :instance_id, :uuid
+      change manage_relationship(:instance_id, :instance, type: :remove)
+      change manage_relationship(:head_id, :head, type: :append)
+    end
+
     read :list do
       description "lists all events"
     end
@@ -107,14 +117,24 @@ defmodule Diffo.Provider.Event do
   relationships do
     belongs_to :instance, Diffo.Provider.Instance do
       description "the instance which fired the event"
-      allow_nil? false
+      allow_nil? true
       public? true
     end
 
-    # has_one :earlier_event, Diffo.Provider.Event do
-    #  description "the earlier event, if any"
-    #  allow_nil? true
-    #  public? true
+    belongs_to :head, Diffo.Provider.Event,
+      allow_nil?: true,
+      public?: true,
+      source_attribute: :head_id
+
+    belongs_to :tail, Diffo.Provider.Event,
+      allow_nil?: true,
+      public?: true,
+      source_attribute: :tail_id
+  end
+
+  validations do
+    # validate present [:instance_id, :head_id], at_most: 1 do
+    #  message "event cannot be related to both instance and head event"
     # end
   end
 

test/provider/event_test.exs

@@ -12,7 +12,7 @@ defmodule Diffo.Provider.EventTest do
 
   setup do
     on_exit(fn ->
-      AshNeo4j.Neo4jHelper.delete_nodes(:Event)
+      AshNeo4j.Neo4jHelper.delete_all()
     end)
   end
 
@@ -29,6 +29,101 @@ defmodule Diffo.Provider.EventTest do
 
       assert event.type == :serviceCreateEvent
       assert event.instance_type == :service
+
+      assert AshNeo4j.Neo4jHelper.nodes_relate_how?(
+               :Instance,
+               %{uuid: instance.id},
+               :Event,
+               %{uuid: event.id},
+               :FIRED,
+               :outgoing
+             )
+    end
+
+    test "create multiple events (no chaining) - success" do
+      specification = Diffo.Provider.create_specification!(%{name: "nbnAccess"})
+      instance = Diffo.Provider.create_instance!(%{specified_by: specification.id})
+
+      event_1 =
+        Diffo.Provider.Event.create!(%{
+          instance_id: instance.id,
+          type: :serviceCreateEvent
+        })
+
+      event_2 =
+        Diffo.Provider.Event.create!(%{
+          instance_id: instance.id,
+          type: :serviceStateChangeEvent
+        })
+
+      assert AshNeo4j.Neo4jHelper.nodes_relate_how?(
+               :Instance,
+               %{uuid: instance.id},
+               :Event,
+               %{uuid: event_1.id},
+               :FIRED,
+               :outgoing
+             )
+
+      assert AshNeo4j.Neo4jHelper.nodes_relate_how?(
+               :Instance,
+               %{uuid: instance.id},
+               :Event,
+               %{uuid: event_2.id},
+               :FIRED,
+               :outgoing
+             )
+    end
+
+    test "create event and chain it before previous event - success" do
+      specification = Diffo.Provider.create_specification!(%{name: "nbnAccess"})
+      instance = Diffo.Provider.create_instance!(%{specified_by: specification.id})
+
+      event_1 =
+        Diffo.Provider.Event.create!(%{
+          instance_id: instance.id,
+          type: :serviceCreateEvent
+        })
+
+      event_2 =
+        Diffo.Provider.Event.create!(%{
+          instance_id: instance.id,
+          type: :serviceStateChangeEvent
+        })
+
+      event_1 =
+        event_1
+        |> Diffo.Provider.Event.chain!(%{
+          instance_id: instance.id,
+          head_id: event_2.id
+        })
+
+      refute AshNeo4j.Neo4jHelper.nodes_relate_how?(
+               :Instance,
+               %{uuid: instance.id},
+               :Event,
+               %{uuid: event_1.id},
+               :FIRED,
+               :outgoing
+             )
+
+      assert AshNeo4j.Neo4jHelper.nodes_relate_how?(
+               :Instance,
+               %{uuid: instance.id},
+               :Event,
+               %{uuid: event_2.id},
+               :FIRED,
+               :outgoing
+             )
+
+      assert AshNeo4j.Neo4jHelper.nodes_relate_how?(
+               :Event,
+               %{uuid: event_2.id},
+               :Event,
+               %{uuid: event_1.id},
+               :AFTER,
+               :outgoing
+             )
     end
   end