+ def set_unreachable(_, _), do: {:error, nil}
+
+ def get_consistently_unreachable do
+ reachability_datetime_threshold = Instances.reachability_datetime_threshold()
+
+ from(i in Instance,
+ where: ^reachability_datetime_threshold > i.unreachable_since,
+ order_by: i.unreachable_since,
+ select: {i.host, i.unreachable_since}
+ )
+ |> Repo.all()
+ end
+
+ defp parse_datetime(datetime) when is_binary(datetime) do
+ NaiveDateTime.from_iso8601(datetime)
+ end
+
+ defp parse_datetime(datetime), do: datetime
+
+ def get_or_update_favicon(%URI{host: host} = instance_uri) do
+ existing_record = Repo.get_by(Instance, %{host: host})
+ now = NaiveDateTime.utc_now()
+
+ if existing_record && existing_record.favicon_updated_at &&
+ NaiveDateTime.diff(now, existing_record.favicon_updated_at) < 86_400 do
+ existing_record.favicon
+ else
+ favicon = scrape_favicon(instance_uri)
+
+ if existing_record do
+ existing_record
+ |> changeset(%{favicon: favicon, favicon_updated_at: now})
+ |> Repo.update()
+ else
+ %Instance{}
+ |> changeset(%{host: host, favicon: favicon, favicon_updated_at: now})
+ |> Repo.insert()
+ end
+
+ favicon
+ end
+ rescue
+ e ->
+ Logger.warn("Instance.get_or_update_favicon(\"#{host}\") error: #{inspect(e)}")
+ nil
+ end
+
+ defp scrape_favicon(%URI{} = instance_uri) do
+ try do
+ with {_, true} <- {:reachable, reachable?(instance_uri.host)},
+ {:ok, %Tesla.Env{body: html}} <-
+ Pleroma.HTTP.get(to_string(instance_uri), [{"accept", "text/html"}], pool: :media),
+ {_, [favicon_rel | _]} when is_binary(favicon_rel) <-
+ {:parse,
+ html |> Floki.parse_document!() |> Floki.attribute("link[rel=icon]", "href")},
+ {_, favicon} when is_binary(favicon) <-
+ {:merge, URI.merge(instance_uri, favicon_rel) |> to_string()} do
+ favicon
+ else
+ {:reachable, false} ->
+ Logger.debug(
+ "Instance.scrape_favicon(\"#{to_string(instance_uri)}\") ignored unreachable host"
+ )
+
+ nil
+
+ _ ->
+ nil
+ end
+ rescue
+ e ->
+ Logger.warn(
+ "Instance.scrape_favicon(\"#{to_string(instance_uri)}\") error: #{inspect(e)}"
+ )
+
+ nil
+ end
+ end