[skip-ci] [WIP] feat: implement PostgreSQL cluster synchronization with architectural improvements

include/proxysql_admin.h

@@ -313,6 +313,10 @@ 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;
 		int cluster_mysql_servers_sync_algorithm;
 		bool cluster_mysql_query_rules_save_to_disk;
 		bool cluster_mysql_servers_save_to_disk;
@@ -321,6 +325,10 @@ 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;
 		int stats_mysql_connection_pool;
 		int stats_mysql_connections;
 		int stats_mysql_query_cache;
@@ -516,6 +524,7 @@ 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) {
@@ -617,6 +626,7 @@ class ProxySQL_Admin {
 //	void flush_admin_variables__from_disk_to_memory(); // commented in 2.3 because unused
 	void flush_admin_variables__from_memory_to_disk();
 	void flush_ldap_variables__from_memory_to_disk();
+	void flush_pgsql_variables__from_memory_to_disk();
 	void load_mysql_servers_to_runtime(const incoming_servers_t& incoming_servers = {}, const runtime_mysql_servers_checksum_t& peer_runtime_mysql_server = {},
 		const mysql_servers_v2_checksum_t& peer_mysql_server_v2 = {});
 	void save_mysql_servers_from_runtime();

include/proxysql_glovars.hpp

@@ -3,6 +3,7 @@
 
 #define CLUSTER_SYNC_INTERFACES_ADMIN "('admin-mysql_ifaces','admin-restapi_port','admin-telnet_admin_ifaces','admin-telnet_stats_ifaces','admin-web_port','admin-pgsql_ifaces')"
 #define CLUSTER_SYNC_INTERFACES_MYSQL "('mysql-interfaces')"
+#define CLUSTER_SYNC_INTERFACES_PGSQL "('pgsql-interfaces')"
 
 #include <memory>
 #include <string.h>

lib/Admin_FlushVariables.cpp

@@ -384,6 +384,10 @@ void ProxySQL_Admin::flush_GENERIC_variables__checksum__database_to_runtime(cons
 		if (GloVars.cluster_sync_interfaces == false) {
 			q += " AND variable_name NOT IN " + string(CLUSTER_SYNC_INTERFACES_ADMIN);
 		}
+	} else if (modname == "pgsql") {
+		if (GloVars.cluster_sync_interfaces == false) {
+			q += " AND variable_name NOT IN " + string(CLUSTER_SYNC_INTERFACES_PGSQL);
+		}
 	}
 	q += " ORDER BY variable_name";
 	admindb->execute_statement(q.c_str(), &error , &cols , &affected_rows , &resultset);
@@ -399,6 +403,8 @@ void ProxySQL_Admin::flush_GENERIC_variables__checksum__database_to_runtime(cons
 		checkvar = &GloVars.checksums_values.mysql_variables;
 	} else if (modname == "ldap") {
 		checkvar = &GloVars.checksums_values.ldap_variables;
+	} else if (modname == "pgsql") {
+		checkvar = &GloVars.checksums_values.pgsql_variables;
 	}
 	assert(checkvar != NULL);
 	checkvar->set_checksum(buf);
@@ -889,6 +895,13 @@ void ProxySQL_Admin::flush_pgsql_variables___database_to_runtime(SQLite3DB* db,
 				q += " AND variable_name NOT IN " + string(CLUSTER_SYNC_INTERFACES_MYSQL);
 			}
 			q += " ORDER BY variable_name";
+
+			// PostgreSQL variables filtering
+			q += ";\nSELECT variable_name, variable_value FROM runtime_global_variables WHERE variable_name LIKE 'pgsql-\%' AND variable_name NOT IN ('pgsql-interfaces')";
+			if (GloVars.cluster_sync_interfaces == false) {
+				q += " AND variable_name NOT IN " + string(CLUSTER_SYNC_INTERFACES_PGSQL);
+			}
+			q += " ORDER BY variable_name";
 			admindb->execute_statement(q.c_str(), &error, &cols, &affected_rows, &resultset);
 			uint64_t hash1 = resultset->raw_checksum();
 			uint32_t d32[2];

lib/PgSQL_Variables_Validator.cpp

@@ -639,3 +639,33 @@ const pgsql_variable_validator pgsql_variable_validator_search_path = {
 	.validate = &pgsql_variable_validate_search_path,
 	.params = {}
 };
+
+
+/**
+ * @brief Validates an integer variable for PostgreSQL.
+ *
+ * This function checks if the provided value is a valid integer representation
+ * and falls within the specified range. The range is defined by the params
+ * parameter.
+ *
+ * @param value The value to validate.
+ * @param params The parameter structure containing the integer range.
+ * @param session Unused parameter.
+ * @param transformed_value If not null, will be set to null.
+ * @return true if the value is a valid integer representation within the specified range, false otherwise.
+ */
+bool pgsql_variable_validate_integer(const char* value, const params_t* params, PgSQL_Session* session, char** transformed_value) {
+   (void)session;
+   if (transformed_value) *transformed_value = nullptr;
+   char* end = nullptr;
+   long num = strtol(value, &end, 10);
+   if (end == value || *end != '\0') return false;
+   if (num < params->int_range.min || num > params->int_range.max) return false;
+   return true;
+}
+
+const pgsql_variable_validator pgsql_variable_validator_integer = {
+	.type = VARIABLE_TYPE_INT,
+	.validate = &pgsql_variable_validate_integer,
+	.params = {}
+};