fix: resolve PostgreSQL cluster sync compilation issues

- Add missing set_metrics() function to ProxySQL_Node_Entry class
- Fix undefined 'd_query' variable in PostgreSQL variables function
- Remove deprecated PostgreSQL functions integrated into pgsql_servers sync
- Add missing admin variables for PostgreSQL modules
- Fix structural compilation issues in set_checksums function
- PostgreSQL cluster sync now builds successfully for both debug and regular builds

Resolves linking errors and compilation failures that prevented
debug and regular builds from completing successfully.

include/ProxySQL_Cluster.hpp

@@ -691,7 +691,5 @@ public:
 		const runtime_pgsql_servers_checksum_t& peer_runtime_pgsql_server = {}, bool fetch_runtime_pgsql_servers = false);
 	void pull_pgsql_users_from_peer(const std::string& expected_checksum, const time_t epoch);
 	void pull_pgsql_variables_from_peer(const std::string& expected_checksum, const time_t epoch);
-	void pull_pgsql_replication_hostgroups_from_peer(const std::string& expected_checksum, const time_t epoch);
-	void pull_pgsql_hostgroup_attributes_from_peer(const std::string& expected_checksum, const time_t epoch);
 };
 #endif /* CLASS_PROXYSQL_CLUSTER_H */

include/proxysql_admin.h

@@ -313,6 +313,7 @@ class ProxySQL_Admin {
 		int cluster_mysql_variables_diffs_before_sync;
 		int cluster_admin_variables_diffs_before_sync;
 		int cluster_ldap_variables_diffs_before_sync;
+		int cluster_pgsql_variables_diffs_before_sync;
 		int cluster_pgsql_query_rules_diffs_before_sync;
 		int cluster_pgsql_servers_diffs_before_sync;
 		int cluster_pgsql_users_diffs_before_sync;
@@ -324,6 +325,7 @@ class ProxySQL_Admin {
 		bool cluster_mysql_variables_save_to_disk;
 		bool cluster_admin_variables_save_to_disk;
 		bool cluster_ldap_variables_save_to_disk;
+		bool cluster_pgsql_variables_save_to_disk;
 		bool cluster_pgsql_query_rules_save_to_disk;
 		bool cluster_pgsql_servers_save_to_disk;
 		bool cluster_pgsql_users_save_to_disk;
@@ -503,6 +505,7 @@ class ProxySQL_Admin {
 		bool checksum_mysql_variables;
 		bool checksum_admin_variables;
 		bool checksum_ldap_variables;
+		bool checksum_pgsql_variables;
 	} checksum_variables;
 	template<enum SERVER_TYPE pt>
 	void public_add_active_users(enum cred_username_type usertype, char *user=NULL) {

lib/ProxySQL_Admin.cpp

@@ -403,13 +403,14 @@ static char * admin_variables_names[]= {
 	(char *)"cluster_pgsql_query_rules_save_to_disk",
 	(char *)"cluster_pgsql_servers_save_to_disk",
 	(char *)"cluster_pgsql_users_save_to_disk",
-	(char *)"cluster_mysql_servers_sync_algorithm",
+		(char *)"cluster_mysql_servers_sync_algorithm",
 	(char *)"checksum_mysql_query_rules",
 	(char *)"checksum_mysql_servers",
 	(char *)"checksum_mysql_users",
 	(char *)"checksum_mysql_variables",
 	(char *)"checksum_admin_variables",
 	(char *)"checksum_ldap_variables",
+	(char *)"checksum_pgsql_variables",
 	(char *)"restapi_enabled",
 	(char *)"restapi_port",
 	(char *)"web_enabled",
@@ -2635,13 +2636,14 @@ ProxySQL_Admin::ProxySQL_Admin() :
 	variables.cluster_pgsql_query_rules_diffs_before_sync = 3;
 	variables.cluster_pgsql_servers_diffs_before_sync = 3;
 	variables.cluster_pgsql_users_diffs_before_sync = 3;
-	variables.cluster_mysql_servers_sync_algorithm = 1;
+		variables.cluster_mysql_servers_sync_algorithm = 1;
 	checksum_variables.checksum_mysql_query_rules = true;
 	checksum_variables.checksum_mysql_servers = true;
 	checksum_variables.checksum_mysql_users = true;
 	checksum_variables.checksum_mysql_variables = true;
 	checksum_variables.checksum_admin_variables = true;
 	checksum_variables.checksum_ldap_variables = true;
+	checksum_variables.checksum_pgsql_variables = true;
 	variables.cluster_mysql_query_rules_save_to_disk = true;
 	variables.cluster_mysql_servers_save_to_disk = true;
 	variables.cluster_mysql_users_save_to_disk = true;
@@ -2653,7 +2655,7 @@ ProxySQL_Admin::ProxySQL_Admin() :
 	variables.cluster_pgsql_query_rules_save_to_disk = true;
 	variables.cluster_pgsql_servers_save_to_disk = true;
 	variables.cluster_pgsql_users_save_to_disk = true;
-	variables.stats_mysql_connection_pool = 60;
+		variables.stats_mysql_connection_pool = 60;
 	variables.stats_mysql_connections = 60;
 	variables.stats_mysql_query_cache = 60;
 	variables.stats_mysql_query_digest_to_disk = 0;