+ @doc """
+ Set the rich media cache based on the expiration time of image.
+
+ Adopt behaviour `Pleroma.Web.RichMedia.Parser.TTL`
+
+ ## Example
+
+ defmodule MyModule do
+ @behaviour Pleroma.Web.RichMedia.Parser.TTL
+ def ttl(data, url) do
+ image_url = Map.get(data, :image)
+ # do some parsing in the url and get the ttl of the image
+ # and return ttl is unix time
+ parse_ttl_from_url(image_url)
+ end
+ end
+
+ Define the module in the config
+
+ config :pleroma, :rich_media,
+ ttl_setters: [MyModule]
+ """
+ def set_ttl_based_on_image({:ok, data}, url) do
+ with {:ok, nil} <- Cachex.ttl(:rich_media_cache, url),
+ ttl when is_number(ttl) <- get_ttl_from_image(data, url) do
+ Cachex.expire_at(:rich_media_cache, url, ttl * 1000)
+ {:ok, data}
+ else
+ _ ->
+ {:ok, data}
+ end
+ end
+
+ defp get_ttl_from_image(data, url) do
+ Pleroma.Config.get([:rich_media, :ttl_setters])
+ |> Enum.reduce({:ok, nil}, fn
+ module, {:ok, _ttl} ->
+ module.ttl(data, url)
+
+ _, error ->
+ error
+ end)
+ end
+