Adding ETA support to the --show-progress in nix-copy-closure

Based on NixOS#6 from shlevy

Author: viric

perl/lib/Nix/CopyClosure.pm

@@ -3,16 +3,13 @@ package Nix::CopyClosure;
 use strict;
 use Nix::Config;
 use Nix::Store;
+use List::Util qw(sum);
 
 
 sub copyTo {
     my ($sshHost, $sshOpts, $storePaths, $compressor, $decompressor,
         $includeOutputs, $dryRun, $sign, $progressViewer, $useSubstitutes) = @_;
 
-    $compressor = "$compressor |" if $compressor ne "";
-    $decompressor = "$decompressor |" if $decompressor ne "";
-    $progressViewer = "$progressViewer |" if $progressViewer ne "";
-
     # Get the closure of this path.
     my @closure = reverse(topoSortPaths(computeFSClosure(0, $includeOutputs,
         map { followLinksToStorePath $_ } @{$storePaths})));
@@ -28,16 +25,23 @@ sub copyTo {
     # we'll want to use ‘--from-stdin’, but we can't rely on the
     # target having this option yet.
     my @missing = ();
+    my $missingSize = 0;
     while (scalar(@closure) > 0) {
         my @ps = splice(@closure, 0, 1500);
         open(READ, "set -f; ssh $sshHost @{$sshOpts} nix-store --check-validity --print-invalid @ps|");
         while (<READ>) {
             chomp;
             push @missing, $_;
+            my ($deriver, $narHash, $time, $narSize, $refs) = queryPathInfo($_, 1);
+            $missingSize += $narSize;
         }
         close READ or die;
     }
 
+    $compressor = "$compressor |" if $compressor ne "";
+    $decompressor = "$decompressor |" if $decompressor ne "";
+    $progressViewer = "$progressViewer -s $missingSize |" if $progressViewer ne "";
+
     # Export the store paths and import them on the remote machine.
     if (scalar @missing > 0) {
         print STDERR "copying ", scalar @missing, " missing paths to ‘$sshHost’...\n";

scripts/nix-copy-closure.in

@@ -4,6 +4,7 @@ use Nix::SSH;
 use Nix::Config;
 use Nix::Store;
 use Nix::CopyClosure;
+use List::Util qw(sum);
 
 
 if (scalar @ARGV < 1) {
@@ -61,7 +62,7 @@ while (@ARGV) {
         $includeOutputs = 1;
     }
     elsif ($arg eq "--show-progress") {
-        $progressViewer = "@pv@";
+        $progressViewer = "pv";
     }
     elsif ($arg eq "--dry-run") {
         $dryRun = 1;
@@ -104,6 +105,11 @@ else { # Copy FROM the remote machine.
 
     close READ or die "nix-store on remote machine `$sshHost' failed: $?";
 
+    my $missingSize = 0;
+    if ($progressViewer ne "") {
+        $missingSize = sum (split ' ', `set -f; ssh @sshOpts $sshHost nix-store -q --size @missing`) or die;
+    }
+
     # Export the store paths on the remote machine and import them locally.
     if (scalar @missing > 0) {
         print STDERR "copying ", scalar @missing, " missing paths from ‘$sshHost’...\n";
@@ -113,7 +119,7 @@ else { # Copy FROM the remote machine.
             }
             $compressor = "| $compressor" if $compressor ne "";
             $decompressor = "$decompressor |" if $decompressor ne "";
-            $progressViewer = "$progressViewer |" if $progressViewer ne "";
+            $progressViewer = "$progressViewer -s $missingSize |" if $progressViewer ne "";
             my $extraOpts = $sign ? "--sign" : "";
             system("set -f; ssh $sshHost @sshOpts 'nix-store --export $extraOpts @missing $compressor' | $progressViewer $decompressor $Nix::Config::binDir/nix-store --import > /dev/null") == 0
                 or die "copying store paths from remote machine `$sshHost' failed: $?";