properly decode policy id

lib/policy_service/events/policy.ex

@@ -1,5 +1,25 @@
 defmodule PolicyService.Events.Policy do
+  @moduledoc """
+  Policy domain events.
+  Contains helpers for common event functionality.
+  """
+
+  alias PolicyService.Aggregates.PolicyId
+
+  defmacro __using__(_opts) do
+    quote do
+      defimpl Commanded.Serialization.JsonDecoder do
+        def decode(%{id: %{org_id: org_id, policy_type: policy_type, application_id: application_id}} = event) do
+          %{event | id: PolicyId.new(org_id, policy_type, application_id)}
+        end
+
+        def decode(event), do: event
+      end
+    end
+  end
+
   defmodule PolicyApplicationSubmitted do
+    use PolicyService.Events.Policy
     @derive Jason.Encoder
     defstruct [
       :id,
@@ -12,6 +32,7 @@ defmodule PolicyService.Events.Policy do
   end
 
   defmodule QuoteRequestSent do
+    use PolicyService.Events.Policy
     @derive Jason.Encoder
     defstruct [
       :id,
@@ -24,6 +45,7 @@ defmodule PolicyService.Events.Policy do
   end
 
   defmodule ProviderQuoteReceived do
+    use PolicyService.Events.Policy
     @derive Jason.Encoder
     defstruct [
       :id,
@@ -39,11 +61,13 @@ defmodule PolicyService.Events.Policy do
   end
 
   defmodule AllQuotesReceived do
+    use PolicyService.Events.Policy
     @derive Jason.Encoder
     defstruct [:id, :quote_count]
   end
 
   defmodule QuoteAccepted do
+    use PolicyService.Events.Policy
     @derive Jason.Encoder
     defstruct [
       :id,
@@ -56,6 +80,7 @@ defmodule PolicyService.Events.Policy do
   end
 
   defmodule SolicitationSent do
+    use PolicyService.Events.Policy
     @derive Jason.Encoder
     defstruct [
       :id,
@@ -68,6 +93,7 @@ defmodule PolicyService.Events.Policy do
   end
 
   defmodule PolicyIssued do
+    use PolicyService.Events.Policy
     @derive Jason.Encoder
     defstruct [
       :id,