From 2baca40984320e1277382f5c8e9ec12c25c43cb1 Mon Sep 17 00:00:00 2001
From: rope <fredrik@nordhammer.it>
Date: Thu, 13 Aug 2026 14:50:14 +0100
Subject: [PATCH] update: progress bar for the copy step

---
 common.nix | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/common.nix b/common.nix
index 06004de..7d5e046 100644
--- a/common.nix
+++ b/common.nix
@@ -12,6 +12,40 @@ let
 
   flake = "git+https://forg.gregersen.it/rope/nixos";
 
+  # Now that the clients only copy, the copy is the whole wait. nix's own
+  # --log-format bar prints counters but no gauge, so render one from the json
+  # log: activity type 103 is the top-level copy-paths, and its type-105
+  # progress results carry [done, expected, running, failed] path counts.
+  # Messages at warning level and above still go through to stderr — otherwise
+  # folding nix's stderr into the filter would swallow the errors too.
+  copyBar = pkgs.writeShellScriptBin "nix-copy-bar" ''
+    set -o pipefail
+    ${pkgs.jq}/bin/jq -Rr --unbuffered '
+      ltrimstr("@nix ") | fromjson? // empty
+      | if   .action == "start"  and .type == 103 then "A \(.id)"
+        elif .action == "result" and .type == 105 then "P \(.id) \(.fields[0]) \(.fields[1])"
+        elif .action == "msg"    and .level <= 2   then "M \(.msg)"
+        else empty end' |
+    {
+      blocks='########################################'
+      drawn=
+      while read -r tag rest; do
+        case "$tag" in
+          A) copy_id=$rest ;;
+          M) [ -n "$drawn" ] && printf '\n' && drawn=
+             printf '%s\n' "$rest" >&2 ;;
+          P) set -- $rest
+             [ "$1" = "''${copy_id:-}" ] && [ "''${3:-0}" -gt 0 ] || continue
+             pct=$(( $2 * 100 / $3 ))
+             printf '\r[%-40s] %3d%%  %d/%d paths' \
+               "''${blocks:0:$(( pct * 40 / 100 ))}" "$pct" "$2" "$3"
+             drawn=1 ;;
+        esac
+      done
+      [ -n "$drawn" ] && printf '\n'
+    }
+  '';
+
   post = "nvd diff $OLD_SYSTEM /run/current-system && (command -v record-update &>/dev/null && record-update $OLD_SYSTEM /run/current-system || true)";
 
   # The server evaluates and builds for itself.
@@ -27,7 +61,7 @@ let
   # fred, not root: root has no key on the server, and require-sigs = false
   # below is a daemon setting, so the daemon takes the unsigned closure from an
   # untrusted user just fine. Only the activation needs sudo.
-  remoteUpdate = "bash -c 'set -o pipefail && OLD_SYSTEM=$(readlink /run/current-system) && NEW=$(ssh fred@nordhammer.it \"nix build --refresh --print-out-paths --out-link prebuild-${config.networking.hostName} --option extra-substituters https://attic.xuyh0120.win/lantian --option extra-trusted-public-keys lantian:EeAUQ+W+6r7EtwnmYjeVwx5kOGEBpjlBfPlzGlTNvHc= ${flake}#nixosConfigurations.${config.networking.hostName}.config.system.build.toplevel\") && nix copy --from ssh://fred@nordhammer.it $NEW && sudo nixos-rebuild switch --no-reexec --store-path $NEW && ${post}'";
+  remoteUpdate = "bash -c 'set -o pipefail && OLD_SYSTEM=$(readlink /run/current-system) && NEW=$(ssh fred@nordhammer.it \"nix build --refresh --print-out-paths --out-link prebuild-${config.networking.hostName} --option extra-substituters https://attic.xuyh0120.win/lantian --option extra-trusted-public-keys lantian:EeAUQ+W+6r7EtwnmYjeVwx5kOGEBpjlBfPlzGlTNvHc= ${flake}#nixosConfigurations.${config.networking.hostName}.config.system.build.toplevel\") && nix copy --from ssh://fred@nordhammer.it $NEW --log-format internal-json 2>&1 | ${copyBar}/bin/nix-copy-bar && sudo nixos-rebuild switch --no-reexec --store-path $NEW && ${post}'";
 in
 {
   imports = [