1 files changed, 82 insertions, 0 deletions
diff --git a/users/Profpatsch/ytextr/default.nix b/users/Profpatsch/ytextr/default.nix
new file mode 100644
index 000000000000..ac630603b90c
--- /dev/null
+++ b/users/Profpatsch/ytextr/default.nix
@@ -0,0 +1,82 @@
+{ depot, pkgs, lib, ... }:
+
+# ytextr is a wrapper arount yt-dlp (previously youtube-dl)
+# that extracts a single video according to my preferred settings.
+#
+# It will be sandboxed to the current directory, since I don’t particularly
+# trust the massive codebase of that tool (with hundreds of contributors).
+#
+# Since the rules for downloading videos is usually against the wishes
+# of proprietary vendors, and a video is many megabytes anyway,
+# it will be fetched from the most recent nixpkgs unstable channel before running.
+
+let
+  bins = depot.nix.getBins pkgs.nix [ "nix-build" ]
+    // depot.nix.getBins pkgs.bubblewrap [ "bwrap" ];
+
+  # Run a command, with the given packages in scope, and `packageNamesAtRuntime` being fetched at the start in the given nix `channel`.
+  nix-run-with-channel =
+    {
+      # The channel to get `packageNamesAtRuntime` from
+      channel
+    , # executable to run with `packageNamesAtRuntime` in PATH
+      # and the argv
+      executable
+    , # A list of nixpkgs package attribute names that should be put into PATH when running `command`.
+      packageNamesAtRuntime
+    ,
+    }: depot.nix.writeExecline "nix-run-with-channel-${channel}" { } [
+      # TODO: prevent race condition by writing a temporary gc root
+      "backtick"
+      "-iE"
+      "storepath"
+      [
+        bins.nix-build
+        "-I"
+        "nixpkgs=channel:${channel}"
+        "--arg"
+        "packageNamesAtRuntimeJsonPath"
+        (pkgs.writeText "packageNamesAtRuntime.json" (builtins.toJSON packageNamesAtRuntime))
+        ./create-symlink-farm.nix
+      ]
+      "importas"
+      "-ui"
+      "PATH"
+      "PATH"
+      "export"
+      "PATH"
+      "\${storepath}/bin:\${PATH}"
+      executable
+      "$@"
+    ];
+
+in
+nix-run-with-channel {
+  channel = "nixos-unstable";
+  packageNamesAtRuntime = [ "yt-dlp" ];
+  executable = depot.nix.writeExecline "ytextr" { readNArgs = 1; } [
+    "getcwd"
+    "-E"
+    "cwd"
+    bins.bwrap
+    "--ro-bind"
+    "/nix/store"
+    "/nix/store"
+    "--ro-bind"
+    "/etc"
+    "/etc"
+    "--bind"
+    "$cwd"
+    "$cwd"
+    "yt-dlp"
+    "--no-playlist"
+    "--write-sub"
+    "--all-subs"
+    "--embed-subs"
+    "--merge-output-format"
+    "mkv"
+    "-f"
+    "bestvideo[height<=?1080]+bestaudio/best"
+    "$1"
+  ];
+}