akkoma/lib/pleroma/web/rich_media/card.ex

150 lines
3.7 KiB
Elixir

defmodule Pleroma.Web.RichMedia.Card do
use Ecto.Schema
import Ecto.Changeset
import Ecto.Query
alias Pleroma.Activity
alias Pleroma.HTML
alias Pleroma.Object
alias Pleroma.Repo
alias Pleroma.Web.RichMedia.Backfill
alias Pleroma.Web.RichMedia.Parser
@cachex Pleroma.Config.get([:cachex, :provider], Cachex)
@config_impl Application.compile_env(:pleroma, [__MODULE__, :config_impl], Pleroma.Config)
@type t :: %__MODULE__{}
schema "rich_media_card" do
field(:url_hash, :binary)
field(:fields, :map)
timestamps()
end
@doc false
def changeset(card, attrs) do
card
|> cast(attrs, [:url_hash, :fields])
|> validate_required([:url_hash, :fields])
|> unique_constraint(:url_hash)
end
@spec create(String.t(), map()) :: {:ok, t()}
def create(url, fields) do
url_hash = url_to_hash(url)
fields = Map.put_new(fields, "url", url)
%__MODULE__{}
|> changeset(%{url_hash: url_hash, fields: fields})
|> Repo.insert(on_conflict: {:replace, [:fields]}, conflict_target: :url_hash)
end
@spec delete(String.t()) :: {:ok, Ecto.Schema.t()} | {:error, Ecto.Changeset.t()} | :ok
def delete(url) do
url_hash = url_to_hash(url)
@cachex.del(:rich_media_cache, url_hash)
case get_by_url(url) do
%__MODULE__{} = card -> Repo.delete(card)
nil -> :ok
end
end
@spec get_by_url(String.t() | nil) :: t() | nil | :error
def get_by_url(url) when is_binary(url) do
if @config_impl.get([:rich_media, :enabled]) do
url_hash = url_to_hash(url)
@cachex.fetch!(:rich_media_cache, url_hash, fn _ ->
result =
__MODULE__
|> where(url_hash: ^url_hash)
|> Repo.one()
case result do
%__MODULE__{} = card -> {:commit, card}
_ -> {:ignore, nil}
end
end)
else
:error
end
end
def get_by_url(nil), do: nil
@spec get_or_backfill_by_url(String.t(), map()) :: t() | nil
def get_or_backfill_by_url(url, backfill_opts \\ %{}) do
case get_by_url(url) do
%__MODULE__{} = card ->
card
nil ->
backfill_opts = Map.put(backfill_opts, :url, url)
Backfill.start(backfill_opts)
nil
:error ->
nil
end
end
@spec get_by_activity(Activity.t()) :: t() | nil | :error
# Fake/Draft activity
def get_by_activity(%Activity{id: "pleroma:fakeid"} = activity) do
with %Object{} = object <- Object.normalize(activity, fetch: false),
url when not is_nil(url) <- HTML.extract_first_external_url_from_object(object) do
case get_by_url(url) do
# Cache hit
%__MODULE__{} = card ->
card
# Cache miss, but fetch for rendering the Draft
_ ->
with {:ok, fields} <- Parser.parse(url),
{:ok, card} <- create(url, fields) do
card
else
_ -> nil
end
end
else
_ ->
nil
end
end
def get_by_activity(activity) do
with %Object{} = object <- Object.normalize(activity, fetch: false),
{_, nil} <- {:cached, get_cached_url(object, activity.id)} do
nil
else
{:cached, url} ->
get_or_backfill_by_url(url, %{activity_id: activity.id})
_ ->
:error
end
end
@spec url_to_hash(String.t()) :: String.t()
def url_to_hash(url) do
:crypto.hash(:sha256, url) |> Base.encode16(case: :lower)
end
defp get_cached_url(object, activity_id) do
key = "URL|#{activity_id}"
@cachex.fetch!(:scrubber_cache, key, fn _ ->
url = HTML.extract_first_external_url_from_object(object)
Activity.HTML.add_cache_key_for(activity_id, key)
{:commit, url}
end)
end
end