[WIP] hooked up basic video downloading; starting work on metadata

config/config.exs

@@ -14,7 +14,8 @@ config :pinchflat,
   yt_dlp_executable: System.find_executable("yt-dlp"),
   yt_dlp_runner: Pinchflat.MediaClient.Backends.YtDlp.CommandRunner,
   # TODO: figure this out
-  media_directory: :not_implemented
+  media_directory: :not_implemented,
+  metadata_directory: Path.join([System.tmp_dir!(), "pinchflat", "metadata"])
 
 # Configures the endpoint
 config :pinchflat, PinchflatWeb.Endpoint,

config/dev.exs

@@ -1,7 +1,8 @@
 import Config
 
 config :pinchflat,
-  media_directory: Path.join([System.tmp_dir!(), "yt-dlp"])
+  media_directory: Path.join([File.cwd!(), "tmp", "videos"]),
+  metadata_directory: Path.join([File.cwd!(), "tmp", "metadata"])
 
 # Configure your database
 config :pinchflat, Pinchflat.Repo,

config/test.exs

@@ -3,7 +3,8 @@ import Config
 config :pinchflat,
   # Specifying backend data here makes mocking and local testing SUPER easy
   yt_dlp_executable: Path.join([File.cwd!(), "/test/support/scripts/yt-dlp-mocks/repeater.sh"]),
-  media_directory: Path.join([System.tmp_dir!(), "yt-dlp"])
+  media_directory: Path.join([File.cwd!(), "tmp", "videos"]),
+  metadata_directory: Path.join([File.cwd!(), "tmp", "metadata"])
 
 config :pinchflat, Oban, testing: :manual
 

lib/pinchflat/media_client/backends/yt_dlp/command_runner.ex

@@ -3,6 +3,8 @@ defmodule Pinchflat.MediaClient.Backends.YtDlp.CommandRunner do
   Runs yt-dlp commands using the `System.cmd/3` function
   """
 
+  require Logger
+
   alias Pinchflat.Utils.StringUtils
   alias Pinchflat.MediaClient.Backends.BackendCommandRunner
 
@@ -20,7 +22,9 @@ defmodule Pinchflat.MediaClient.Backends.YtDlp.CommandRunner do
   @impl BackendCommandRunner
   def run(url, command_opts) do
     command = backend_executable()
-    formatted_command_opts = parse_options(command_opts) ++ [url]
+    formatted_command_opts = [url] ++ parse_options(command_opts)
+
+    Logger.debug("[yt-dlp] called with: #{Enum.join(formatted_command_opts, " ")}")
 
     case System.cmd(command, formatted_command_opts, stderr_to_stdout: true) do
       {output, 0} -> {:ok, output}
@@ -55,7 +59,7 @@ defmodule Pinchflat.MediaClient.Backends.YtDlp.CommandRunner do
   end
 
   defp parse_option(arg, acc) when is_binary(arg) do
-    [arg | acc]
+    acc ++ [arg]
   end
 
   defp backend_executable do

lib/pinchflat/media_client/backends/yt_dlp/metadata_parser.ex

@@ -0,0 +1,7 @@
+defmodule Pinchflat.MediaClient.Backends.YtDlp.MetadataParser do
+  def parse_for_media_item(metadata) do
+    %{
+      video_filepath: metadata["filepath"]
+    }
+  end
+end

lib/pinchflat/media_client/backends/yt_dlp/video.ex

@@ -3,17 +3,31 @@ defmodule Pinchflat.MediaClient.Backends.YtDlp.Video do
   Contains utilities for working with singular videos
   """
 
+  alias Pinchflat.Utils.StringUtils
+
   @doc """
   Downloads a single video (and possible metadata) directly to its
   final destination. Returns the parsed JSON output from yt-dlp.
 
+  It writes to file and then immediately reads from it since printing
+  to stdout also contains any warnings/errors that may have occurred,
+  even if the command is otherwise successful (which creates invalid
+  JSON).
+
   Returns {:ok, map()} | {:error, any, ...}.
+
+  TODO: test changes (writing to then reading from a file)
   """
   def download(url, command_opts \\ []) do
-    opts = [:no_simulate, print: "%()j"] ++ command_opts
+    json_output_path = Path.join([metadata_directory(), "#{StringUtils.random_string()}.json"])
+    # These must stay in exactly this order, hence why I'm giving it its own variable.
+    # Also, can't use RAM file since yt-dlp needs a concrete filepath.
+    print_to_file_opts = [{:print_to_file, "after_move:%()j"}, json_output_path]
+    opts = [:no_simulate] ++ print_to_file_opts ++ command_opts
 
-    with {:ok, output} <- backend_runner().run(url, opts),
-         {:ok, parsed_json} <- Phoenix.json_library().decode(output) do
+    with {:ok, _} <- backend_runner().run(url, opts),
+         {:ok, file_body} <- File.read(json_output_path),
+         {:ok, parsed_json} <- Phoenix.json_library().decode(file_body) do
       {:ok, parsed_json}
     else
       err -> err
@@ -23,4 +37,8 @@ defmodule Pinchflat.MediaClient.Backends.YtDlp.Video do
   defp backend_runner do
     Application.get_env(:pinchflat, :yt_dlp_runner)
   end
+
+  defp metadata_directory do
+    Application.get_env(:pinchflat, :metadata_directory)
+  end
 end

lib/pinchflat/media_client/video_downloader.ex

@@ -8,15 +8,19 @@ defmodule Pinchflat.MediaClient.VideoDownloader do
   it open-ish for future expansion (just in case).
   """
 
+  alias Pinchflat.Repo
+  alias Pinchflat.Media
+  alias Pinchflat.Media.MediaItem
   alias Pinchflat.Profiles.MediaProfile
 
   alias Pinchflat.MediaClient.Backends.YtDlp.Video, as: YtDlpVideo
   alias Pinchflat.Profiles.Options.YtDlp.OptionBuilder, as: YtDlpOptionBuilder
+  alias Pinchflat.MediaClient.Backends.YtDlp.MetadataParser, as: YtDlpMetadataParser
 
   @doc """
   Downloads a single video based on the settings in the given media profile.
 
-  Returns {:ok, %ChannelDetails{}} | {:error, any, ...}.
+  Returns {:ok, map()} | {:error, any, ...}.
   """
   def download_for_media_profile(url, %MediaProfile{} = media_profile, backend \\ :yt_dlp) do
     option_builder = option_builder(backend)
@@ -26,6 +30,29 @@ defmodule Pinchflat.MediaClient.VideoDownloader do
     video_backend.download(url, options)
   end
 
+  @doc """
+  TODO: test
+  TODO: consider removing the above function? I don't know if it's actually useful
+  TODO: save metadata filepath to media item record
+  TODO: consider saving the output JSON to the database instead of the filesystem.
+        reason: would make updating metadata easier (no orphans). Also queryable.
+  """
+  def download_for_media_item(%MediaItem{} = media_item, backend \\ :yt_dlp) do
+    item_with_preloads = Repo.preload(media_item, channel: :media_profile)
+    media_profile = item_with_preloads.channel.media_profile
+
+    case download_for_media_profile(media_item.media_id, media_profile, backend) do
+      {:ok, parsed_json} ->
+        parser = metadata_parser(backend)
+        parsed_attrs = parser.parse_for_media_item(parsed_json)
+
+        Media.update_media_item(media_item, parsed_attrs)
+
+      err ->
+        err
+    end
+  end
+
   defp option_builder(backend) do
     case backend do
       :yt_dlp -> YtDlpOptionBuilder
@@ -37,4 +64,10 @@ defmodule Pinchflat.MediaClient.VideoDownloader do
       :yt_dlp -> YtDlpVideo
     end
   end
+
+  defp metadata_parser(backend) do
+    case backend do
+      :yt_dlp -> YtDlpMetadataParser
+    end
+  end
 end

lib/pinchflat/profiles/options/yt_dlp/option_builder.ex

@@ -24,15 +24,10 @@ defmodule Pinchflat.Profiles.Options.YtDlp.OptionBuilder do
     # see: https://github.com/yt-dlp/yt-dlp#output-template
     {:ok,
      [
-       :write_thumbnail,
-       :write_subs,
        :embed_metadata,
        :embed_thumbnail,
        :embed_subs,
-       :write_info_json,
-       :write_auto_subs,
        :no_progress,
-       convert_thumbnails: "jpg",
        sub_langs: "en.*",
        output: Path.join(base_directory(), output_path)
      ]}

lib/pinchflat/utils/string_utils.ex

@@ -11,4 +11,13 @@ defmodule Pinchflat.Utils.StringUtils do
     |> String.replace(~r/[\s_]/, "-")
     |> String.downcase()
   end
+
+  @doc """
+  TODO: test
+  """
+  def random_string(length \\ 32) do
+    :crypto.strong_rand_bytes(length)
+    |> Base.encode16(case: :lower)
+    |> String.slice(0..(length - 1))
+  end
 end

lib/pinchflat/workers/video_download_worker.ex

@@ -0,0 +1,27 @@
+defmodule Pinchflat.Workers.VideoDownloadWorker do
+  @moduledoc false
+
+  use Oban.Worker,
+    queue: :media_fetching,
+    unique: [period: :infinity, states: [:available, :scheduled, :retryable]],
+    tags: ["media_itwm", "media_fetching"]
+
+  alias Pinchflat.Media
+  alias Pinchflat.MediaClient.VideoDownloader
+
+  @impl Oban.Worker
+  @doc """
+  TODO: test
+  """
+  def perform(%Oban.Job{args: %{"id" => media_item_id}}) do
+    media_item = Media.get_media_item!(media_item_id)
+
+    case VideoDownloader.download_for_media_item(media_item) do
+      {:ok, _} ->
+        {:ok, media_item}
+
+      err ->
+        err
+    end
+  end
+end