CompressLog: Add zstd compression

doc/manual/src/plugins/README.md

@@ -42,14 +42,22 @@ Sets CircleCI status.
 
 ## Compress build logs
 
-Compresses build logs after a build with bzip2.
+Compresses build logs after a build with bzip2 or zstd.
 
 ### Configuration options
 
 - `compress_build_logs`
 
 Enable log compression
 
+- `compress_build_logs_compression`
+
+Which compression format to use. Valid values are bzip2 (default) and zstd.
+
+- `compress_build_logs_silent`
+
+Whether to compress logs silently.
+
 ### Example
 
 ```xml

nixos-modules/hydra.nix

@@ -408,6 +408,7 @@ in
         requires = [ "hydra-init.service" ];
         after = [ "hydra-init.service" ];
         restartTriggers = [ hydraConf ];
+        path = [ pkgs.zstd ];
         environment = env // {
           PGPASSFILE = "${baseDir}/pgpass-queue-runner"; # grrr
           HYDRA_DBI = "${env.HYDRA_DBI};application_name=hydra-notify";
@@ -458,10 +459,15 @@ in
     # logs automatically after a step finishes, but this doesn't work
     # if the queue runner is stopped prematurely.
     systemd.services.hydra-compress-logs =
-      { path = [ pkgs.bzip2 ];
+      { path = [ pkgs.bzip2 pkgs.zstd ];
         script =
           ''
-            find ${baseDir}/build-logs -type f -name "*.drv" -mtime +3 -size +0c | xargs -r bzip2 -v -f
+            set -eou pipefail
+            compression=$(sed -nr 's/compress_build_logs_compression = ()/\1/p' ${baseDir}/hydra.conf)
+            if [[ $compression == zstd ]]; then
+              compression="zstd --rm"
+            fi
+            find ${baseDir}/build-logs -type f -name "*.drv" -mtime +3 -size +0c | xargs -r $compression --force --quiet
           '';
         startAt = "Sun 01:45";
       };

src/lib/Hydra/Helper/Nix.pm

@@ -174,6 +174,9 @@ sub getDrvLogPath {
     for ($fn . $bucketed, $fn . $bucketed . ".bz2") {
         return $_ if -f $_;
     }
+    for ($fn . $bucketed, $fn . $bucketed . ".zst") {
+        return $_ if -f $_;
+    }
     return undef;
 }
 

src/lib/Hydra/Plugin/CompressLog.pm

@@ -9,11 +9,24 @@ use Hydra::Helper::CatalystUtils;
 sub stepFinished {
     my ($self, $step, $logPath) = @_;
 
-    my $doCompress = $self->{config}->{'compress_build_logs'} // "1";
+    my $doCompress = $self->{config}->{'compress_build_logs'} // '1';
+    my $silent = $self->{config}->{'compress_build_logs_silent'} // '0';
+    my $compression = $self->{config}->{'compress_build_logs_compression'} // 'bzip2';
 
-    if ($doCompress eq "1" && -e $logPath) {
-        print STDERR "compressing ‘$logPath’...\n";
-        system("bzip2", "--force", $logPath);
+    if (not -e $logPath or $doCompress ne "1") {
+        return;
+    }
+
+    if ($silent ne '1') {
+        print STDERR "compressing '$logPath' with $compression...\n";
+    }
+
+    if ($compression eq 'bzip2') {
+        system('bzip2', '--force', $logPath);
+    } elsif ($compression eq 'zstd') {
+        system('zstd', '--rm', '--quiet', '-T0', $logPath);
+    } else {
+        print STDERR "unknown compression type '$compression'\n";
     }
 }
 

src/lib/Hydra/View/NixLog.pm

@@ -16,7 +16,10 @@ sub process {
 
     my $tail = int($c->stash->{tail} // "0");
 
-    if ($logPath =~ /\.bz2$/) {
+    if ($logPath =~ /\.zst$/) {
+        my $doTail = $tail ? "| tail -n '$tail'" : "";
+        open($fh, "-|", "zstd -dc < '$logPath' $doTail") or die;
+    } elsif ($logPath =~ /\.bz2$/) {
         my $doTail = $tail ? "| tail -n '$tail'" : "";
         open($fh, "-|", "bzip2 -dc < '$logPath' $doTail") or die;
     } else {