@callback bulk_create(user_payloads :: Enum.t()) :: :ok

Bulk add multiple users to the cache at once.

Returns :ok.

@callback create(payload :: map()) :: Nostrum.Struct.User.t()

Add a new user to the cache based on the Discord Gateway payload.

Returns a Nostrum.Struct.User.t/0 struct representing the created user.

@callback delete(snowflake :: Nostrum.Struct.User.id()) :: :noop | Nostrum.Struct.User.t()

Delete a user by ID.

Returns the deleted user if present in the cache, or :noop if the user was not cached.

@callback get(id :: Nostrum.Struct.User.id()) ::
  {:ok, Nostrum.Struct.User.t()} | {:error, atom()}

Retrieves a user from the cache by id.

If successful, returns {:ok, user}. Otherwise, returns {:error, reason}.

example

Example

case Nostrum.Cache.UserCache.get(1111222233334444) do
  {:ok, user} ->
    "We found " <> user.username
  {:error, _reason} ->
    "No es bueno"
end

@callback qlc_handle() :: :qlc.query_handle()

Return a query handle for usage with :qlc.

This is used by nostrum to provide automatic joins between the member and the user cache, and may be used for other functions in the future.

The Erlang manual on Implementing a QLC Table contains examples for implementation.

The query handle must return items in the form {user_id, user}, where user_id is a Nostrum.Struct.User.id/0 and user is a Nostrum.Struct.User.t/0.

@callback update(payload :: map()) ::
  :noop | {Nostrum.Struct.User.t(), Nostrum.Struct.User.t()}

Update a user in the cache based on payload sent via the Gateway.

Returns :noop if the user has not been updated in the cache, or {old_user, new_user} is the user has been written to the cache.