postgresql: Enable systemd integration for 9.6+

This allows, finally, proper detection when postgresql is ready to
accept connections. Until now, it was possible that services depending
on postgresql would fail in a race condition trying to connect
to postgresql.

1 files changed, 3 insertions, 0 deletions

diff --git a/nixos/modules/services/databases/postgresql.nix b/nixos/modules/services/databases/postgresql.nix
index f592be0e768..aeab445a998 100644
--- a/nixos/modules/services/databases/postgresql.nix
+++ b/nixos/modules/services/databases/postgresql.nix
@@ -238,6 +238,9 @@ in
             User = "postgres";
             Group = "postgres";
             PermissionsStartOnly = true;
+            Type = if lib.versionAtLeast cfg.package.version "9.6"
+                   then "notify"
+                   else "simple";
 
             # Shut down Postgres using SIGINT ("Fast Shutdown mode").  See
             # http://www.postgresql.org/docs/current/static/server-shutdown.html