From e1f9bbb8f214c32a87b45e0aa4f7a15a8f631f7d Mon Sep 17 00:00:00 2001
From: Xe <me@christine.website>
Date: Fri, 29 Apr 2022 18:43:00 +0000
Subject: [PATCH] generate tarball.nix with a script

Signed-off-by: Xe <me@christine.website>
---
 flake.nix      | 12 ++++--------
 gen_tarball.sh | 17 +++++++++++++++++
 tarball.nix    |  7 +++++++
 3 files changed, 28 insertions(+), 8 deletions(-)
 create mode 100755 gen_tarball.sh
 create mode 100644 tarball.nix

diff --git a/flake.nix b/flake.nix
index dd7bf09..2314110 100644
--- a/flake.nix
+++ b/flake.nix
@@ -25,25 +25,21 @@
         };
         version = builtins.substring 0 8 self.lastModifiedDate;
       in {
-        packages = rec {
+        packages = let tsmeta = import ./tarball.nix; in rec {
           imagebuilder = pkgs.buildGoModule {
             pname = "taildeck-imagebuilder";
-            inherit version;
+            inherit (tsmeta) version;
             src = ./.;
 
             vendorSha256 =
               "sha256-pQpattmS9VmO3ZIQUFn66az8GSmB4IvYhTTCFn6SUmo=";
           };
 
-          tsTarball = builtins.fetchurl {
-            url =
-              "https://pkgs.tailscale.com/stable/tailscale_1.24.2_amd64.tgz";
-            sha256 = "1b697g694vigzmv5q48l1d3pjc9l5gwzazggnfi7z9prb9cvlnx2";
-          };
+          tsTarball = tsmeta.tarball;
 
           image = pkgs.stdenv.mkDerivation {
             pname = "tailscale-image";
-            version = "1.24.2";
+            inherit (tsmeta) version;
             buildInputs = with pkgs; [ squashfsTools imagebuilder ];
             phases = "installPhase";
 
diff --git a/gen_tarball.sh b/gen_tarball.sh
new file mode 100755
index 0000000..80b737b
--- /dev/null
+++ b/gen_tarball.sh
@@ -0,0 +1,17 @@
+#!/usr/bin/env nix-shell
+#! nix-shell -p curl -p jq -p nix -i bash
+
+set -euo pipefail
+
+version="$(curl https://pkgs.tailscale.com/stable/?mode=json | jq .Tarballs.amd64 -r)"
+url="https://pkgs.tailscale.com/stable/${version}"
+shasum="$(nix-prefetch-url "${url}")"
+
+rm -f tarball.nix
+echo "{
+  version = \"$(echo ${version} | cut -d_ -f2)\";
+  tarball = builtins.fetchurl {
+    url = \"${url}\";
+    sha256 = \"${shasum}\";
+  };
+}" >> tarball.nix
diff --git a/tarball.nix b/tarball.nix
new file mode 100644
index 0000000..0bc3feb
--- /dev/null
+++ b/tarball.nix
@@ -0,0 +1,7 @@
+{
+  version = "1.24.2";
+  tarball = builtins.fetchurl {
+    url = "https://pkgs.tailscale.com/stable/tailscale_1.24.2_amd64.tgz";
+    sha256 = "1b697g694vigzmv5q48l1d3pjc9l5gwzazggnfi7z9prb9cvlnx2";
+  };
+}