Track usage of media files and add a job to clean them

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/mix/tasks/mobilizon/media/clean_orphan.ex

@@ -0,0 +1,87 @@
+defmodule Mix.Tasks.Mobilizon.Media.CleanOrphan do
+  @moduledoc """
+  Task to accept an instance follow request
+  """
+  use Mix.Task
+  import Mix.Tasks.Mobilizon.Common
+  alias Mobilizon.Service.CleanOrphanMedia
+
+  @shortdoc "Clean orphan media"
+
+  @grace_period Mobilizon.Config.get([:instance, :orphan_upload_grace_period_hours], 48)
+
+  @impl Mix.Task
+  def run(options) do
+    {options, [], []} =
+      OptionParser.parse(
+        options,
+        strict: [
+          dry_run: :boolean,
+          days: :integer,
+          verbose: :boolean
+        ],
+        aliases: [
+          d: :days,
+          v: :verbose
+        ]
+      )
+
+    dry_run = Keyword.get(options, :dry_run, false)
+    grace_period = Keyword.get(options, :days)
+    grace_period = if is_nil(grace_period), do: @grace_period, else: grace_period * 24
+    verbose = Keyword.get(options, :verbose, false)
+
+    start_mobilizon()
+
+    case CleanOrphanMedia.clean(dry_run: dry_run, grace_period: grace_period) do
+      {:ok, medias} ->
+        if length(medias) > 0 do
+          if dry_run or verbose do
+            details(medias, dry_run, verbose)
+          end
+
+          result(dry_run, length(medias))
+        else
+          empty_result(dry_run)
+        end
+
+        :ok
+
+      _err ->
+        shell_error("Error while cleaning orphan media files")
+    end
+  end
+
+  @spec details(list(Media.t()), boolean(), boolean()) :: :ok
+  defp details(medias, dry_run, verbose) do
+    cond do
+      dry_run ->
+        shell_info("List of files that would have been deleted")
+
+      verbose ->
+        shell_info("List of files that have been deleted")
+    end
+
+    Enum.each(medias, fn media ->
+      shell_info("ID: #{media.id}, Actor: #{media.actor_id}, URL: #{media.file.url}")
+    end)
+  end
+
+  @spec result(boolean(), boolean()) :: :ok
+  defp result(dry_run, nb_medias) do
+    if dry_run do
+      shell_info("#{nb_medias} files would have been deleted")
+    else
+      shell_info("#{nb_medias} files have been deleted")
+    end
+  end
+
+  @spec empty_result(boolean()) :: :ok
+  defp empty_result(dry_run) do
+    if dry_run do
+      shell_info("No files would have been deleted")
+    else
+      shell_info("No files were deleted")
+    end
+  end
+end