nixos/gitlab: Switch from unicorn to puma

Puma is the new upstream default server since GitLab 13.

nixos/modules/services/misc/defaultUnicornConfig.rb

@@ -1,69 +0,0 @@
-worker_processes 3
-
-listen ENV["UNICORN_PATH"] + "/tmp/sockets/gitlab.socket", :backlog => 1024
-listen "/run/gitlab/gitlab.socket", :backlog => 1024
-
-working_directory ENV["GITLAB_PATH"]
-
-pid ENV["UNICORN_PATH"] + "/tmp/pids/unicorn.pid"
-
-timeout 60
-
-# combine Ruby 2.0.0dev or REE with "preload_app true" for memory savings
-# http://rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
-preload_app true
-GC.respond_to?(:copy_on_write_friendly=) and
-  GC.copy_on_write_friendly = true
-
-check_client_connection false
-
-before_fork do |server, worker|
-  # the following is highly recommended for Rails + "preload_app true"
-  # as there's no need for the master process to hold a connection
-  defined?(ActiveRecord::Base) and
-    ActiveRecord::Base.connection.disconnect!
-
-  # The following is only recommended for memory/DB-constrained
-  # installations.  It is not needed if your system can house
-  # twice as many worker_processes as you have configured.
-  #
-  # This allows a new master process to incrementally
-  # phase out the old master process with SIGTTOU to avoid a
-  # thundering herd (especially in the "preload_app false" case)
-  # when doing a transparent upgrade.  The last worker spawned
-  # will then kill off the old master process with a SIGQUIT.
-  old_pid = "#{server.config[:pid]}.oldbin"
-  if old_pid != server.pid
-    begin
-      sig = (worker.nr + 1) >= server.worker_processes ? :QUIT : :TTOU
-      Process.kill(sig, File.read(old_pid).to_i)
-    rescue Errno::ENOENT, Errno::ESRCH
-    end
-  end
-
-  # Throttle the master from forking too quickly by sleeping.  Due
-  # to the implementation of standard Unix signal handlers, this
-  # helps (but does not completely) prevent identical, repeated signals
-  # from being lost when the receiving process is busy.
-  # sleep 1
-end
-
-after_fork do |server, worker|
-  # per-process listener ports for debugging/admin/migrations
-  # addr = "127.0.0.1:#{9293 + worker.nr}"
-  # server.listen(addr, :tries => -1, :delay => 5, :tcp_nopush => true)
-
-  # the following is *required* for Rails + "preload_app true",
-  defined?(ActiveRecord::Base) and
-    ActiveRecord::Base.establish_connection
-
-  # reset prometheus client, this will cause any opened metrics files to be closed
-  defined?(::Prometheus::Client.reinitialize_on_pid_change) &&
-    Prometheus::Client.reinitialize_on_pid_change
-
-  # if preload_app is true, then you may also want to check and
-  # restart any other shared sockets/descriptors such as Memcached,
-  # and Redis.  TokyoCabinet file handles are safe to reuse
-  # between any number of forked children (assuming your kernel
-  # correctly implements pread()/pwrite() system calls)
-end

nixos/modules/services/misc/gitlab.nix

@@ -142,7 +142,7 @@ let
 
   gitlabEnv = {
     HOME = "${cfg.statePath}/home";
-    UNICORN_PATH = "${cfg.statePath}/";
+    PUMA_PATH = "${cfg.statePath}/";
     GITLAB_PATH = "${cfg.packages.gitlab}/share/gitlab/";
     SCHEMA = "${cfg.statePath}/db/structure.sql";
     GITLAB_UPLOADS_PATH = "${cfg.statePath}/uploads";
@@ -725,8 +725,6 @@ in {
       "L+ /run/gitlab/uploads - - - - ${cfg.statePath}/uploads"
 
       "L+ /run/gitlab/shell-config.yml - - - - ${pkgs.writeText "config.yml" (builtins.toJSON gitlabShellConfig)}"
-
-      "L+ ${cfg.statePath}/config/unicorn.rb - - - - ${./defaultUnicornConfig.rb}"
     ];
 
     systemd.services.gitlab-sidekiq = {
@@ -873,7 +871,9 @@ in {
             set -eu
 
             chown --no-dereference '${cfg.user}':'${cfg.group}' '${cfg.statePath}'/*
-            chown --no-dereference '${cfg.user}':'${cfg.group}' '${cfg.statePath}'/config/*
+            if [[ ! -z "$(ls -A '${cfg.statePath}'/config/)" ]]; then
+              chown --no-dereference '${cfg.user}':'${cfg.group}' '${cfg.statePath}'/config/*
+            fi
           '';
           preStart = ''
             set -eu
@@ -956,7 +956,7 @@ in {
           "+${pkgs.writeShellScript "gitlab-pre-start-full-privileges" preStartFullPrivileges}"
           "${pkgs.writeShellScript "gitlab-pre-start" preStart}"
         ];
-        ExecStart = "${cfg.packages.gitlab.rubyEnv}/bin/unicorn -c ${cfg.statePath}/config/unicorn.rb -E production";
+        ExecStart = "${cfg.packages.gitlab.rubyEnv}/bin/puma -C ${cfg.statePath}/config/puma.rb -e production";
       };
 
     };