postgres: add a config.socketDir option

* Defaults to config.dataDir * Allows customization of socketDir for users who do not wish it fixed to dataDir * Sockets are limited to around [100 chars](https://linux.die.net/man/7/unix): * In the case that the default or desired dataDir absolute path exceeds this char limit, postgres will fail to start if it is also used for socketDir * In this case, dataDir can remain as desired and socketDir can be set separately to a shorter absolute path
juspay · Jan 17, 2024 · cb0ae89 · cb0ae89
1 parent 4fb82e0
commit cb0ae89
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Showing 2 changed files with 12 additions and 5 deletions.
diff --git a/nix/postgres/default.nix b/nix/postgres/default.nix
@@ -50,6 +50,12 @@ in
       description = "The DB data directory";
     };
 
+    socketDir = lib.mkOption {
+      type = lib.types.str;
+      default = config.dataDir;
+      description = "The DB socket directory";
+    };
+
     hbaConf =
       let
         hbaConfSubmodule = lib.types.submodule {
@@ -161,7 +167,7 @@ in
         default = {
           listen_addresses = config.listen_addresses;
           port = config.port;
-          unix_socket_directories = config.dataDir;
+          unix_socket_directories = config.socketDir;
           hba_file = "${config.hbaConfFile}";
         };
       };
@@ -181,7 +187,7 @@ in
         default = {
           listen_addresses = config.listen_addresses;
           port = config.port;
-          unix_socket_directories = lib.mkDefault config.dataDir;
+          unix_socket_directories = lib.mkDefault config.socketDir;
           hba_file = "${config.hbaConfFile}";
         };
         example = lib.literalExpression ''
@@ -311,12 +317,13 @@ in
                   text = ''
                     set -euo pipefail
                     PGDATA=$(readlink -f "${config.dataDir}")
+                    PGSOCKETDIR=$(readlink -f "${config.socketDir}")
                     export PGDATA
-                    postgres -k "$PGDATA"
+                    postgres -k "$PGSOCKETDIR"
                   '';
                 };
                 pg_isreadyArgs = [
-                  "-h $(readlink -f ${config.dataDir})"
+                  "-h $(readlink -f \"${config.socketDir}\")"
                   "-p ${toString config.port}"
                   "-d template1"
                 ] ++ (lib.optional (config.superuser != null) "-U ${config.superuser}");

diff --git a/nix/postgres/setup-script.nix b/nix/postgres/setup-script.nix
@@ -100,7 +100,7 @@ in
       echo
       echo "PostgreSQL is setting up the initial database."
       echo
-      PGHOST=$(mktemp -d "$(readlink -f ${config.dataDir})/pg-init-XXXXXX")
+      PGHOST=$(mkdir -p "${config.socketDir}" && mktemp -d "$(readlink -f "${config.socketDir}")/pg-init-XXXXXX")
       export PGHOST
 
       function remove_tmp_pg_init_sock_dir() {