Fix 'text_admin_stats-t' timing issue

test/tap/tests/test_admin_stats-t.cpp

@@ -27,6 +27,43 @@
 
 using std::string;
 using std::to_string;
+using std::vector;
+
+int wait_for_history_update(MYSQL* proxysql_admin, uint32_t timeout) {
+	uint64_t previous_timestamp = 0;
+	uint32_t retries = 0;
+
+	int res = EXIT_FAILURE;
+
+	while (true) {
+		MYSQL_QUERY(proxysql_admin, "SELECT TIMESTAMP FROM history_mysql_status_variables ORDER BY timestamp DESC LIMIT 1");
+		MYSQL_RES* my_res = mysql_store_result(proxysql_admin);
+		vector<mysql_res_row> rows = extract_mysql_rows(my_res);
+
+		if (rows.empty() || rows[0].empty()) {
+			res = 3;
+			break;
+		} else {
+			uint64_t new_timestamp = std::strtoll(rows[0][0].c_str(), NULL, 10);
+
+			if (previous_timestamp == 0) {
+				previous_timestamp = new_timestamp;
+			} else if (retries > timeout) {
+				res = 2;
+				break;
+			} else if (new_timestamp > previous_timestamp) {
+				res = EXIT_SUCCESS;
+				break;
+			} else {
+				diag("Waiting 'history_mysql_status_variables' update...");
+				retries += 1;
+				sleep(1);
+			}
+		}
+	}
+
+	return res;
+}
 
 int main(int argc, char** argv) {
 	CommandLine cl;
@@ -72,7 +109,7 @@ int main(int argc, char** argv) {
 	MYSQL_RES* result = mysql_store_result(proxysql_admin);
 	MYSQL_ROW row = mysql_fetch_row(result);
 
-	if (row[0]) 
+	if (row && row[0])
 		lookup_row_count = strtoll(row[0], nullptr, 10);
 	
 	mysql_free_result(result);
@@ -91,7 +128,7 @@ int main(int argc, char** argv) {
 	result = mysql_store_result(proxysql_admin);
 	row = mysql_fetch_row(result);
 
-	if (row[0]) 
+	if (row && row[0])
 		distinct_timestamp_count = strtoll(row[0], nullptr, 10);
 
 	mysql_free_result(result);
@@ -103,23 +140,29 @@ int main(int argc, char** argv) {
 	);
 
 	// Test 3: Matching distinct variable_id counts in lookup and history table
-	int64_t distinct_var_ids_in_history = 0;
-	int64_t distinct_var_ids_in_lookup = 0;
+	int64_t distinct_var_ids_in_history = -1;
+	int64_t distinct_var_ids_in_lookup = -1;
 	
 	MYSQL_QUERY(proxysql_admin, "SELECT COUNT(DISTINCT(variable_id)) from history_mysql_status_variables_lookup");
+	if (result == NULL) {
+		diag("NULL result received. Errno: '%d', Error: '%s'", mysql_errno(proxysql_admin), mysql_error(proxysql_admin));
+	}
 	result = mysql_store_result(proxysql_admin);
 	row = mysql_fetch_row(result);
 
-	if (row[0])
+	if (row && row[0])
 		distinct_var_ids_in_lookup = strtoll(row[0], nullptr, 10);
 
 	mysql_free_result(result);
 
 	MYSQL_QUERY(proxysql_admin, "SELECT COUNT(DISTINCT(variable_id)) from history_mysql_status_variables");
 	result = mysql_store_result(proxysql_admin);
+	if (result == NULL) {
+		diag("NULL result received. Errno: '%d', Error: '%s'", mysql_errno(proxysql_admin), mysql_error(proxysql_admin));
+	}
 	row = mysql_fetch_row(result);
 
-	if (row[0])
+	if (row && row[0])
 		distinct_var_ids_in_history = strtoll(row[0], nullptr, 10);
 
 	mysql_free_result(result);
@@ -160,29 +203,36 @@ int main(int argc, char** argv) {
 	int64_t history_rows_before = 0;
 	int64_t history_rows_after = 0;
 
+	// Increase interval and wait for next round of inserts.
+	// distinct_var_ids_in_history should equal the # of records inserted.
+	// If the interval isn't updated, then there'd be double what's expected.
+	new_stats_interval_sec = 10;
+	MYSQL_QUERY(proxysql_admin, ("SET admin-stats_mysql_connections=" + to_string(new_stats_interval_sec)).c_str());
+	MYSQL_QUERY(proxysql_admin, "LOAD ADMIN VARIABLES TO RUNTIME");
+
+	// Wait for the next 'history update' before waiting the specified time of the new interval.
+	int w_res = wait_for_history_update(proxysql_admin, 20);
+	if (w_res == EXIT_FAILURE) {
+		fprintf(stderr, "Line %d, 'wait_for_history_update' failed: %d\n", __LINE__, w_res);
+		return EXIT_FAILURE;
+	}
+
 	MYSQL_QUERY(proxysql_admin, "SELECT COUNT(*) FROM history_mysql_status_variables");
 	result = mysql_store_result(proxysql_admin);
 	row = mysql_fetch_row(result);
 
-	if (row[0])
+	if (row && row[0])
 		history_rows_before = strtoll(row[0], nullptr, 10);
 
 	mysql_free_result(result);
 
-	// Increase interval and wait for next round of inserts.
-	// distinct_var_ids_in_history should equal the # of records inserted.
-	// If the interval isn't updated, then there'd be double what's expected.
-	new_stats_interval_sec = 10;
-	MYSQL_QUERY(proxysql_admin, ("SET admin-stats_mysql_connections=" + to_string(new_stats_interval_sec)).c_str());
-	MYSQL_QUERY(proxysql_admin, "LOAD ADMIN VARIABLES TO RUNTIME");
-
 	sleep(new_stats_interval_sec + 1); // give it time to insert next round of stats
 
 	MYSQL_QUERY(proxysql_admin, "SELECT COUNT(*) FROM history_mysql_status_variables");
 	result = mysql_store_result(proxysql_admin);
 	row = mysql_fetch_row(result);
 
-	if (row[0])
+	if (row && row[0])
 		history_rows_after = strtoll(row[0], nullptr, 10);
 
 	mysql_free_result(result);