pinchflat/lib/pinchflat/media_client/video_downloader.ex

83 lines
2.8 KiB
Elixir

defmodule Pinchflat.MediaClient.VideoDownloader do
@moduledoc """
This is the integration layer for actually downloading videos.
It takes into account the media profile's settings in order
to download the video with the desired options.
Technically hardcodes the yt-dlp backend for now, but should leave
it open-ish for future expansion (just in case).
"""
alias Pinchflat.Repo
alias Pinchflat.Media
alias Pinchflat.Media.MediaItem
alias Pinchflat.MediaClient.Backends.YtDlp.Video, as: YtDlpVideo
alias Pinchflat.Profiles.Options.YtDlp.DownloadOptionBuilder, as: YtDlpDownloadOptionBuilder
alias Pinchflat.MediaClient.Backends.YtDlp.MetadataParser, as: YtDlpMetadataParser
alias Pinchflat.MediaClient.Backends.YtDlp.MetadataFileHelpers, as: YtDlpMetadataHelpers
@doc """
Downloads a video for a media item, updating the media item based on the metadata
returned by the backend. Also saves the entire metadata response to the associated
media_metadata record.
NOTE: related methods (like the download worker) won't download if the media item's source
is set to not download media. However, I'm not enforcing that here since I need this for testing.
This may change in the future but I'm not stressed.
Returns {:ok, %MediaItem{}} | {:error, any, ...any}
"""
def download_for_media_item(%MediaItem{} = media_item, backend \\ :yt_dlp) do
item_with_preloads = Repo.preload(media_item, [:metadata, source: :media_profile])
case download_with_options(media_item.original_url, item_with_preloads, backend) do
{:ok, parsed_json} ->
{parser, helpers} = metadata_parsers(backend)
parsed_attrs =
parsed_json
|> parser.parse_for_media_item()
|> Map.merge(%{
media_downloaded_at: DateTime.utc_now(),
metadata: %{
metadata_filepath: helpers.compress_and_store_metadata_for(media_item, parsed_json),
thumbnail_filepath: helpers.download_and_store_thumbnail_for(media_item, parsed_json)
}
})
# Don't forgor to use preloaded associations or updates to
# associations won't work!
Media.update_media_item(item_with_preloads, parsed_attrs)
err ->
err
end
end
defp download_with_options(url, item_with_preloads, backend) do
option_builder = option_builder(backend)
video_backend = video_backend(backend)
{:ok, options} = option_builder.build(item_with_preloads)
video_backend.download(url, options)
end
defp option_builder(backend) do
case backend do
:yt_dlp -> YtDlpDownloadOptionBuilder
end
end
defp video_backend(backend) do
case backend do
:yt_dlp -> YtDlpVideo
end
end
defp metadata_parsers(backend) do
case backend do
:yt_dlp -> {YtDlpMetadataParser, YtDlpMetadataHelpers}
end
end
end