View Source Ash.Resource.Change behaviour (ash v3.4.4)

The behaviour for an action-specific resource change.

init/1 is defined automatically by use Ash.Resource.Change, but can be implemented if you want to validate/transform any options passed to the module.

The main function is change/3. It takes the changeset, any options that were provided when this change was configured on a resource, and the context, which currently only has the actor.

Summary

Types

context()

ref()

t()

Callbacks

after_batch(changesets_and_results, opts, context)

Runs on each batch result after it is dispatched to the data layer.

atomic(t, t, t)

atomic?()

batch_callbacks?(changesets_or_query, opts, context)

Whether or not batch callbacks should be run (if they are defined). Defaults to true.

batch_change(changesets, opts, context)

Replaces change/3 for batch actions, allowing to optimize changes for bulk actions.

before_batch(changesets, opts, context)

Runs on each batch before it is dispatched to the data layer.

change(changeset, opts, context)

has_after_batch?()

has_batch_change?()

has_before_batch?()

has_change?()

init(opts)

Types

context()

@type context() :: Ash.Resource.Change.Context.t()

ref()

@type ref() :: {module(), Keyword.t()} | module()

t()

@type t() :: %Ash.Resource.Change{
  always_atomic?: term(),
  change: term(),
  description: term(),
  on: term(),
  only_when_valid?: term(),
  where: term()
}

Callbacks

after_batch(changesets_and_results, opts, context)

(optional)

@callback after_batch(
  changesets_and_results :: [{Ash.Changeset.t(), Ash.Resource.record()}],
  opts :: Keyword.t(),
  context :: Ash.Resource.Change.Context.t()
) ::
  :ok
  | Enumerable.t(
      {:ok, Ash.Resource.record()}
      | {:error, Ash.Error.t()}
      | Ash.Notifier.Notification.t()
    )

Runs on each batch result after it is dispatched to the data layer.

atomic(t, t, t)

(optional)

@callback atomic(Ash.Changeset.t(), Keyword.t(), Ash.Resource.Change.Context.t()) ::
  {:ok, Ash.Changeset.t()}
  | {:atomic, %{optional(atom()) => Ash.Expr.t() | {:atomic, Ash.Expr.t()}}}
  | {:atomic, Ash.Changeset.t(), %{optional(atom()) => Ash.Expr.t()}}
  | {:atomic, Ash.Changeset.t(), %{optional(atom()) => Ash.Expr.t()},
     [
       {:atomic, involved_fields :: [atom()] | :*,
        condition_expr :: Ash.Expr.t(), error_expr :: Ash.Expr.t()}
     ]}
  | {:not_atomic, String.t()}
  | :ok
  | {:error, term()}

atomic?()

@callback atomic?() :: boolean()

batch_callbacks?(changesets_or_query, opts, context)

@callback batch_callbacks?(
  changesets_or_query :: [Ash.Changeset.t()] | Ash.Query.t(),
  opts :: Keyword.t(),
  context :: Ash.Resource.Change.Context.t()
) :: boolean()

Whether or not batch callbacks should be run (if they are defined). Defaults to true.

batch_change(changesets, opts, context)

(optional)

@callback batch_change(
  changesets :: [Ash.Changeset.t()],
  opts :: Keyword.t(),
  context :: Ash.Resource.Change.Context.t()
) :: Enumerable.t(Ash.Changeset.t())

Replaces change/3 for batch actions, allowing to optimize changes for bulk actions.

You can define only batch_change/3, and it will be used for both single and batch actions. It cannot, however, be used in place of the atomic/3 callback.

before_batch(changesets, opts, context)

(optional)

@callback before_batch(
  changesets :: [Ash.Changeset.t()],
  opts :: Keyword.t(),
  context :: Ash.Resource.Change.Context.t()
) :: Enumerable.t(Ash.Changeset.t() | Ash.Notifier.Notification.t())

Runs on each batch before it is dispatched to the data layer.

change(changeset, opts, context)

(optional)

@callback change(
  changeset :: Ash.Changeset.t(),
  opts :: Keyword.t(),
  context :: Ash.Resource.Change.Context.t()
) :: Ash.Changeset.t()

has_after_batch?()

@callback has_after_batch?() :: boolean()

has_batch_change?()

@callback has_batch_change?() :: boolean()

has_before_batch?()

@callback has_before_batch?() :: boolean()

has_change?()

@callback has_change?() :: boolean()

init(opts)

@callback init(opts :: Keyword.t()) :: {:ok, Keyword.t()} | {:error, term()}