Create serializer module and reuse it across the application

lib/paper_trail.ex

@@ -3,6 +3,7 @@ defmodule PaperTrail do
 
  alias PaperTrail.Version
  alias PaperTrail.RepoClient
+ alias PaperTrail.Serializer
 
  defdelegate get_version(record), to: PaperTrail.VersionQueries
  defdelegate get_version(model_or_record, id_or_options), to: PaperTrail.VersionQueries
@@ -11,6 +12,13 @@ defmodule PaperTrail do
  defdelegate get_versions(model_or_record, id_or_options), to: PaperTrail.VersionQueries
  defdelegate get_versions(model, id, options), to: PaperTrail.VersionQueries
  defdelegate get_current_model(version), to: PaperTrail.VersionQueries
+ defdelegate make_version_struct(version, model, options), to: Serializer
+ defdelegate get_sequence_from_model(changeset), to: Serializer
+ defdelegate serialize(data), to: Serializer
+ defdelegate get_sequence_id(table_name), to: Serializer
+ defdelegate add_prefix(changeset, prefix), to: Serializer
+ defdelegate get_item_type(data), to: Serializer
+ defdelegate get_model_id(model), to: Serializer
 
  @doc """
  Inserts a record to the database with a related version insertion in one transaction
@@ -138,107 +146,4 @@ defmodule PaperTrail do
  end)
  |> elem(1)
  end
-
- defp make_version_struct(%{event: "insert"}, model, options) do
- originator = PaperTrail.RepoClient.originator()
- originator_ref = options[originator[:name]] || options[:originator]
-
- %Version{
- event: "insert",
- item_type: get_item_type(model),
- item_id: get_model_id(model),
- item_changes: serialize(model),
- originator_id:
- case originator_ref do
- nil -> nil
- _ -> originator_ref |> Map.get(:id)
- end,
- origin: options[:origin],
- meta: options[:meta]
- }
- |> add_prefix(options[:prefix])
- end
-
- defp make_version_struct(%{event: "update"}, changeset, options) do
- originator = PaperTrail.RepoClient.originator()
- originator_ref = options[originator[:name]] || options[:originator]
-
- %Version{
- event: "update",
- item_type: get_item_type(changeset),
- item_id: get_model_id(changeset),
- item_changes: changeset.changes,
- originator_id:
- case originator_ref do
- nil -> nil
- _ -> originator_ref |> Map.get(:id)
- end,
- origin: options[:origin],
- meta: options[:meta]
- }
- |> add_prefix(options[:prefix])
- end
-
- defp make_version_struct(%{event: "delete"}, model_or_changeset, options) do
- originator = PaperTrail.RepoClient.originator()
- originator_ref = options[originator[:name]] || options[:originator]
-
- %Version{
- event: "delete",
- item_type: get_item_type(model_or_changeset),
- item_id: get_model_id(model_or_changeset),
- item_changes: serialize(model_or_changeset),
- originator_id:
- case originator_ref do
- nil -> nil
- _ -> originator_ref |> Map.get(:id)
- end,
- origin: options[:origin],
- meta: options[:meta]
- }
- |> add_prefix(options[:prefix])
- end
-
- defp get_sequence_from_model(changeset) do
- table_name =
- case Map.get(changeset, :data) do
- nil -> changeset.__struct__.__schema__(:source)
- _ -> changeset.data.__struct__.__schema__(:source)
- end
-
- get_sequence_id(table_name)
- end
-
- defp get_sequence_id(table_name) do
- Ecto.Adapters.SQL.query!(RepoClient.repo(), "select last_value FROM #{table_name}_id_seq").rows
- |> List.first()
- |> List.first()
- end
-
- defp serialize(%Ecto.Changeset{data: data}), do: serialize(data)
-
- defp serialize(model) do
- relationships = model.__struct__.__schema__(:associations)
- Map.drop(model, [:__struct__, :__meta__] ++ relationships)
- end
-
- defp add_prefix(changeset, nil), do: changeset
- defp add_prefix(changeset, prefix), do: Ecto.put_meta(changeset, prefix: prefix)
-
- defp get_item_type(%Ecto.Changeset{data: data}), do: get_item_type(data)
- defp get_item_type(model), do: model.__struct__ |> Module.split() |> List.last()
-
- def get_model_id(%Ecto.Changeset{data: data}), do: get_model_id(data)
-
- def get_model_id(model) do
- {_, model_id} = List.first(Ecto.primary_key(model))
-
- case PaperTrail.Version.__schema__(:type, :item_id) do
- :integer ->
- model_id
-
- _ ->
- "#{model_id}"
- end
- end
 end

lib/paper_trail/multi.ex

@@ -4,6 +4,7 @@ defmodule PaperTrail.Multi do
  alias PaperTrail
  alias PaperTrail.Version
  alias PaperTrail.RepoClient
+ alias PaperTrail.Serializer
 
  defdelegate new(), to: Ecto.Multi
  defdelegate append(lhs, rhs), to: Ecto.Multi
@@ -14,6 +15,13 @@ defmodule PaperTrail.Multi do
  defdelegate run(multi, name, run), to: Ecto.Multi
  defdelegate run(multi, name, mod, fun, args), to: Ecto.Multi
  defdelegate to_list(multi), to: Ecto.Multi
+ defdelegate make_version_struct(version, model, options), to: Serializer
+ defdelegate get_sequence_from_model(changeset), to: Serializer
+ defdelegate serialize(data), to: Serializer
+ defdelegate get_sequence_id(table_name), to: Serializer
+ defdelegate add_prefix(changeset, prefix), to: Serializer
+ defdelegate get_item_type(data), to: Serializer
+ defdelegate get_model_id(model), to: Serializer
 
  def insert(%Ecto.Multi{} = multi, changeset, options \\ [
  origin: nil, meta: nil, originator: nil, prefix: nil, model_key: :model, version_key: :version
@@ -145,107 +153,4 @@ defmodule PaperTrail.Multi do
  end
  end
  end
-
- defp make_version_struct(%{event: "insert"}, model, options) do
- originator = PaperTrail.RepoClient.originator()
- originator_ref = options[originator[:name]] || options[:originator]
-
- %Version{
- event: "insert",
- item_type: get_item_type(model),
- item_id: get_model_id(model),
- item_changes: serialize(model),
- originator_id:
- case originator_ref do
- nil -> nil
- _ -> originator_ref |> Map.get(:id)
- end,
- origin: options[:origin],
- meta: options[:meta]
- }
- |> add_prefix(options[:prefix])
- end
-
- defp make_version_struct(%{event: "update"}, changeset, options) do
- originator = PaperTrail.RepoClient.originator()
- originator_ref = options[originator[:name]] || options[:originator]
-
- %Version{
- event: "update",
- item_type: get_item_type(changeset),
- item_id: get_model_id(changeset),
- item_changes: changeset.changes,
- originator_id:
- case originator_ref do
- nil -> nil
- _ -> originator_ref |> Map.get(:id)
- end,
- origin: options[:origin],
- meta: options[:meta]
- }
- |> add_prefix(options[:prefix])
- end
-
- defp make_version_struct(%{event: "delete"}, model_or_changeset, options) do
- originator = PaperTrail.RepoClient.originator()
- originator_ref = options[originator[:name]] || options[:originator]
-
- %Version{
- event: "delete",
- item_type: get_item_type(model_or_changeset),
- item_id: get_model_id(model_or_changeset),
- item_changes: serialize(model_or_changeset),
- originator_id:
- case originator_ref do
- nil -> nil
- _ -> originator_ref |> Map.get(:id)
- end,
- origin: options[:origin],
- meta: options[:meta]
- }
- |> add_prefix(options[:prefix])
- end
-
- defp get_sequence_from_model(changeset) do
- table_name =
- case Map.get(changeset, :data) do
- nil -> changeset.__struct__.__schema__(:source)
- _ -> changeset.data.__struct__.__schema__(:source)
- end
-
- get_sequence_id(table_name)
- end
-
- defp get_sequence_id(table_name) do
- Ecto.Adapters.SQL.query!(RepoClient.repo(), "select last_value FROM #{table_name}_id_seq").rows
- |> List.first()
- |> List.first()
- end
-
- defp serialize(%Ecto.Changeset{data: data}), do: serialize(data)
-
- defp serialize(model) do
- relationships = model.__struct__.__schema__(:associations)
- Map.drop(model, [:__struct__, :__meta__] ++ relationships)
- end
-
- defp add_prefix(changeset, nil), do: changeset
- defp add_prefix(changeset, prefix), do: Ecto.put_meta(changeset, prefix: prefix)
-
- defp get_item_type(%Ecto.Changeset{data: data}), do: get_item_type(data)
- defp get_item_type(model), do: model.__struct__ |> Module.split() |> List.last()
-
- defp get_model_id(%Ecto.Changeset{data: data}), do: get_model_id(data)
-
- defp get_model_id(model) do
- {_, model_id} = List.first(Ecto.primary_key(model))
-
- case PaperTrail.Version.__schema__(:type, :item_id) do
- :integer ->
- model_id
-
- _ ->
- "#{model_id}"
- end
- end
 end

lib/paper_trail/serializer.ex

@@ -0,0 +1,110 @@
+defmodule PaperTrail.Serializer do
+
+ alias PaperTrail.RepoClient
+ alias PaperTrail.Version
+
+ def make_version_struct(%{event: "insert"}, model, options) do
+ originator = RepoClient.originator()
+ originator_ref = options[originator[:name]] || options[:originator]
+
+ %Version{
+ event: "insert",
+ item_type: get_item_type(model),
+ item_id: get_model_id(model),
+ item_changes: serialize(model),
+ originator_id:
+ case originator_ref do
+ nil -> nil
+ _ -> originator_ref |> Map.get(:id)
+ end,
+ origin: options[:origin],
+ meta: options[:meta]
+ }
+ |> add_prefix(options[:prefix])
+ end
+
+ def make_version_struct(%{event: "update"}, changeset, options) do
+ originator = RepoClient.originator()
+ originator_ref = options[originator[:name]] || options[:originator]
+
+ %Version{
+ event: "update",
+ item_type: get_item_type(changeset),
+ item_id: get_model_id(changeset),
+ item_changes: changeset.changes,
+ originator_id:
+ case originator_ref do
+ nil -> nil
+ _ -> originator_ref |> Map.get(:id)
+ end,
+ origin: options[:origin],
+ meta: options[:meta]
+ }
+ |> add_prefix(options[:prefix])
+ end
+
+ def make_version_struct(%{event: "delete"}, model_or_changeset, options) do
+ originator = RepoClient.originator()
+ originator_ref = options[originator[:name]] || options[:originator]
+
+ %Version{
+ event: "delete",
+ item_type: get_item_type(model_or_changeset),
+ item_id: get_model_id(model_or_changeset),
+ item_changes: serialize(model_or_changeset),
+ originator_id:
+ case originator_ref do
+ nil -> nil
+ _ -> originator_ref |> Map.get(:id)
+ end,
+ origin: options[:origin],
+ meta: options[:meta]
+ }
+ |> add_prefix(options[:prefix])
+ end
+
+ def get_sequence_from_model(changeset) do
+ table_name =
+ case Map.get(changeset, :data) do
+ nil -> changeset.__struct__.__schema__(:source)
+ _ -> changeset.data.__struct__.__schema__(:source)
+ end
+
+ get_sequence_id(table_name)
+ end
+
+ def get_sequence_id(table_name) do
+ Ecto.Adapters.SQL.query!(RepoClient.repo(), "select last_value FROM #{table_name}_id_seq").rows
+ |> List.first()
+ |> List.first()
+ end
+
+ def serialize(nil), do: nil
+
+ def serialize(%Ecto.Changeset{data: data}), do: serialize(data)
+
+ def serialize(model) do
+ relationships = model.__struct__.__schema__(:associations)
+ Map.drop(model, [:__struct__, :__meta__] ++ relationships)
+ end
+
+ def add_prefix(changeset, nil), do: changeset
+ def add_prefix(changeset, prefix), do: Ecto.put_meta(changeset, prefix: prefix)
+
+ def get_item_type(%Ecto.Changeset{data: data}), do: get_item_type(data)
+ def get_item_type(%schema{}), do: schema |> Module.split() |> List.last()
+
+ def get_model_id(%Ecto.Changeset{data: data}), do: get_model_id(data)
+
+ def get_model_id(model) do
+ {_, model_id} = List.first(Ecto.primary_key(model))
+
+ case PaperTrail.Version.__schema__(:type, :item_id) do
+ :integer ->
+ model_id
+
+ _ ->
+ "#{model_id}"
+ end
+ end
+end