From 2a4426560813b702a302dadbe53e684d1ab03f47 Mon Sep 17 00:00:00 2001
From: Aaron Andersen <aaron@fosslib.net>
Date: Sat, 1 Aug 2020 10:02:14 -0400
Subject: [PATCH] nixos/postgresql: replace extraConfig option with settings
 option

---
 .../modules/services/databases/postgresql.nix | 56 ++++++++++++++-----
 nixos/tests/postgresql-wal-receiver.nix       | 24 ++++----
 2 files changed, 54 insertions(+), 26 deletions(-)

diff --git a/nixos/modules/services/databases/postgresql.nix b/nixos/modules/services/databases/postgresql.nix
index c726a08e34f..5056d50153f 100644
--- a/nixos/modules/services/databases/postgresql.nix
+++ b/nixos/modules/services/databases/postgresql.nix
@@ -11,23 +11,23 @@ let
       then cfg.package
       else cfg.package.withPackages (_: cfg.extraPlugins);
 
+  toStr = value:
+    if true == value then "yes"
+    else if false == value then "no"
+    else if isString value then "'${lib.replaceStrings ["'"] ["''"] value}'"
+    else toString value;
+
   # The main PostgreSQL configuration file.
-  configFile = pkgs.writeText "postgresql.conf"
-    ''
-      hba_file = '${pkgs.writeText "pg_hba.conf" cfg.authentication}'
-      ident_file = '${pkgs.writeText "pg_ident.conf" cfg.identMap}'
-      log_destination = 'stderr'
-      log_line_prefix = '${cfg.logLinePrefix}'
-      listen_addresses = '${if cfg.enableTCPIP then "*" else "localhost"}'
-      port = ${toString cfg.port}
-      ${cfg.extraConfig}
-    '';
+  configFile = pkgs.writeText "postgresql.conf" (concatStringsSep "\n" (mapAttrsToList (n: v: "${n} = ${toStr v}") cfg.settings));
 
   groupAccessAvailable = versionAtLeast postgresql.version "11.0";
 
 in
 
 {
+  imports = [
+    (mkRemovedOptionModule [ "services" "postgresql" "extraConfig" ] "Use services.postgresql.settings instead.")
+  ];
 
   ###### interface
 
@@ -212,10 +212,28 @@ in
         '';
       };
 
-      extraConfig = mkOption {
-        type = types.lines;
-        default = "";
-        description = "Additional text to be appended to <filename>postgresql.conf</filename>.";
+      settings = mkOption {
+        type = with types; attrsOf (oneOf [ bool float int str ]);
+        default = {};
+        description = ''
+          PostgreSQL configuration. Refer to
+          <link xlink:href="https://www.postgresql.org/docs/11/config-setting.html#CONFIG-SETTING-CONFIGURATION-FILE"/>
+          for an overview of <literal>postgresql.conf</literal>.
+
+          <note><para>
+            String values will automatically be enclosed in single quotes. Single quotes will be
+            escaped with two single quotes as described by the upstream documentation linked above.
+          </para></note>
+        '';
+        example = literalExample ''
+          {
+            log_connections = true;
+            log_statement = "all";
+            logging_collector = true
+            log_disconnections = true
+            log_destination = lib.mkForce "syslog";
+          }
+        '';
       };
 
       recoveryConfig = mkOption {
@@ -245,6 +263,16 @@ in
 
   config = mkIf cfg.enable {
 
+    services.postgresql.settings =
+      {
+        hba_file = "${pkgs.writeText "pg_hba.conf" cfg.authentication}";
+        ident_file = "${pkgs.writeText "pg_ident.conf" cfg.identMap}";
+        log_destination = "stderr";
+        log_line_prefix = cfg.logLinePrefix;
+        listen_addresses = if cfg.enableTCPIP then "*" else "localhost";
+        port = cfg.port;
+      };
+
     services.postgresql.package =
       # Note: when changing the default, make it conditional on
       # ‘system.stateVersion’ to maintain compatibility with existing
diff --git a/nixos/tests/postgresql-wal-receiver.nix b/nixos/tests/postgresql-wal-receiver.nix
index 3be95187fe2..432b46234f9 100644
--- a/nixos/tests/postgresql-wal-receiver.nix
+++ b/nixos/tests/postgresql-wal-receiver.nix
@@ -14,13 +14,10 @@ let
         baseBackupDir = "/tmp/pg_basebackup";
         walBackupDir = "/tmp/pg_wal";
         atLeast12 = lib.versionAtLeast pkg.version "12.0";
-        restoreCommand = ''
-          restore_command = 'cp ${walBackupDir}/%f %p'
-        '';
 
         recoveryFile = if atLeast12
             then pkgs.writeTextDir "recovery.signal" ""
-            else pkgs.writeTextDir "recovery.conf" "${restoreCommand}";
+            else pkgs.writeTextDir "recovery.conf" "restore_command = 'cp ${walBackupDir}/%f %p'";
 
       in {
         name = "postgresql-wal-receiver-${postgresqlPackage}";
@@ -30,14 +27,17 @@ let
           services.postgresql = {
             package = pkg;
             enable = true;
-            extraConfig = ''
-              wal_level = archive # alias for replica on pg >= 9.6
-              max_wal_senders = 10
-              max_replication_slots = 10
-            '' + lib.optionalString atLeast12 ''
-              ${restoreCommand}
-              recovery_end_command = 'touch recovery.done'
-            '';
+            settings = lib.mkMerge [
+              {
+                wal_level = "archive"; # alias for replica on pg >= 9.6
+                max_wal_senders = 10;
+                max_replication_slots = 10;
+              }
+              (lib.mkIf atLeast12 {
+                restore_command = "cp ${walBackupDir}/%f %p";
+                recovery_end_command = "touch recovery.done";
+              })
+            ];
             authentication = ''
               host replication ${replicationUser} all trust
             '';