Added test for connections timeout

Added test that verifies that client connections are dropped because of:
- mysql-wait_timeout
- mysql-max_transaction_time

IT also helped finding a bug in how mysql-max_transaction_time was handled

lib/MySQL_Thread.cpp

@@ -3306,7 +3306,7 @@ void MySQL_Thread::ProcessAllSessions_MaintenanceLoop(MySQL_Session *sess, unsig
 		if (sess->active_transactions == 0) {
 			sess->transaction_started_at = 0;
 		} else {
-			if (sess_active_transactions == 0) {
+			if (sess->transaction_started_at == 0) {
 				sess->transaction_started_at = curtime;
 			}
 		}

test/tap/tap/utils.cpp

@@ -169,7 +169,9 @@ int add_more_rows_test_sbtest1(int num_rows, MYSQL *mysql) {
 		q << "INSERT INTO test.sbtest1 (k, c, pad) values ";
 		bool put_comma = false;
 		int i=0;
-		for (i=0; i<num_rows && i<20+rand()%50 ; ++i) {
+		unsigned int cnt=5+rand()%50;
+		if (cnt > num_rows) cnt = num_rows;
+		for (i=0; i<cnt ; ++i) {
 			num_rows--;
 			int k = dist(mt);
 			std::stringstream c;

test/tap/tests/kill_connection2-t.cpp

@@ -0,0 +1,187 @@
+#include <vector>
+#include <string>
+#include <stdio.h>
+#include <cstring>
+#include <unistd.h>
+#include <mysql.h>
+
+#include "tap.h"
+#include "command_line.h"
+#include "utils.h"
+
+
+/*
+This test verifies that client connections are dropped because of:
+- mysql-wait_timeout
+- mysql-max_transaction_time
+*/
+
+const int NUM_CONNS = 5;
+
+int run_q(MYSQL *mysql, const char *q) {
+	MYSQL_QUERY(mysql,q);
+	return 0;
+}
+
+MYSQL * conns[NUM_CONNS];
+unsigned long mythreadid[NUM_CONNS];
+
+int create_connections(CommandLine& cl) {
+	for (int i = 0; i < NUM_CONNS ; i++) {
+		MYSQL * mysql = mysql_init(NULL);
+		if (!mysql) {
+			fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(mysql));
+			return exit_status();
+		}
+
+		if (!mysql_real_connect(mysql, cl.host, cl.username, cl.password, NULL, cl.port, NULL, 0)) {
+			fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(mysql));
+			return exit_status();
+		}
+		conns[i] = mysql;
+	}
+	return 0;
+}
+
+int find_tids() {
+	for (int i = 0; i < NUM_CONNS ; i++) {
+		MYSQL * mysql = conns[i];
+		unsigned long tid;
+		MYSQL_ROW row;
+		MYSQL_QUERY(mysql, "SELECT CONNECTION_ID()");
+		MYSQL_RES * proxy_res = mysql_store_result(mysql);
+		while ((row = mysql_fetch_row(proxy_res))) {
+			tid = atoll(row[0]);
+		}
+		mysql_free_result(proxy_res);
+		ok(tid == mysql_thread_id(mysql), "tid: %lu, mysql_thread_id(): %lu", tid, mysql_thread_id(mysql));
+		mythreadid[i] = tid;
+	}
+
+	return 0;
+}
+
+int main(int argc, char** argv) {
+	CommandLine cl;
+
+	int np = 0;
+	np += NUM_CONNS ;	// to get connection id
+	np += NUM_CONNS ;	// failed query on killed connection due to timeout
+	np += NUM_CONNS ;	// to get connection id
+	np += NUM_CONNS ;	// to run BEGIN
+	np += NUM_CONNS ;	// to run first DO 1
+	np += NUM_CONNS ;	// failed query on killed connection due transaction timeout
+
+	plan(np);
+
+	if (cl.getEnv()) {
+		diag("Failed to get the required environmental variables.");
+		return -1;
+	}
+
+
+	MYSQL* proxysql_admin = mysql_init(NULL);
+	// Initialize connections
+	if (!proxysql_admin) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql_admin));
+		return -1;
+	}
+
+	if (!mysql_real_connect(proxysql_admin, cl.host, cl.admin_username, cl.admin_password, NULL, cl.admin_port, NULL, 0)) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql_admin));
+		return -1;
+	}
+
+	MYSQL_QUERY(proxysql_admin, "SET mysql-have_ssl='true'");
+	MYSQL_QUERY(proxysql_admin, "SET mysql-have_compress='true'");
+	MYSQL_QUERY(proxysql_admin, "SET mysql-auto_increment_delay_multiplex=10"); // to ensure multiplexing stays disabled
+	MYSQL_QUERY(proxysql_admin, "SET mysql-wait_timeout=6000"); // to force a close
+	MYSQL_QUERY(proxysql_admin, "LOAD MYSQL VARIABLES TO RUNTIME");
+
+	int rc = 0;
+	rc = create_connections(cl);
+	if (rc != 0) {
+		return exit_status();
+	}
+
+	for (int i = 0; i < NUM_CONNS ; i++) {
+		MYSQL * mysql = conns[i];
+		if (i == 0) {
+			if (create_table_test_sbtest1(10,mysql)) {
+				fprintf(stderr, "File %s, line %d, Error: create_table_test_sbtest1() failed\n", __FILE__, __LINE__);
+				return exit_status();
+			}
+		} else {
+			if (add_more_rows_test_sbtest1(10,mysql)) {
+				fprintf(stderr, "File %s, line %d, Error: add_more_rows_sbtest1() failed\n", __FILE__, __LINE__);
+				return exit_status();
+			}
+		}
+	}
+
+	rc = find_tids();
+	if (rc != 0) {
+		return exit_status();
+	}
+
+	diag("Sleeping for 10 seconds");
+	for (int i = 0; i < 10 ; i++) {
+		fprintf(stderr,".");
+		sleep(1);
+	}
+	fprintf(stderr,"\n");
+
+	for (int i = 0; i < NUM_CONNS ; i++) {
+		MYSQL * mysql = conns[i];
+		int rc = run_q(mysql, "DO 1");
+		ok(rc != 0, (rc == 0 ? "Connection still alive" : "Connection killed"));
+	}
+
+	MYSQL_QUERY(proxysql_admin, "SET mysql-wait_timeout=3600000"); // to not force a close on wait
+	MYSQL_QUERY(proxysql_admin, "SET mysql-max_transaction_time=17000"); // to force a close on transaction	
+	MYSQL_QUERY(proxysql_admin, "LOAD MYSQL VARIABLES TO RUNTIME");
+
+	rc = create_connections(cl);
+	if (rc != 0) {
+		return exit_status();
+	}
+
+	rc = find_tids();
+	if (rc != 0) {
+		return exit_status();
+	}
+
+	for (int i = 0; i < NUM_CONNS ; i++) {
+		MYSQL * mysql = conns[i];
+		int rc = run_q(mysql, "BEGIN");
+		ok(rc == 0, "Running BEGIN on new connection");
+	}
+
+	diag("Sleeping for 12 seconds");
+	for (int i = 0; i < 12 ; i++) {
+		fprintf(stderr,".");
+		sleep(1);
+	}
+	fprintf(stderr,"\n");
+
+	for (int i = 0; i < NUM_CONNS ; i++) {
+		MYSQL * mysql = conns[i];
+		int rc = run_q(mysql, "DO 1");
+		ok(rc == 0, (rc == 0 ? "Connection still alive" : "Connection killed"));
+	}
+
+	diag("Sleeping for 12 seconds");
+	for (int i = 0; i < 12 ; i++) {
+		fprintf(stderr,".");
+		sleep(1);
+	}
+	fprintf(stderr,"\n");
+
+	for (int i = 0; i < NUM_CONNS ; i++) {
+		MYSQL * mysql = conns[i];
+		int rc = run_q(mysql, "DO 1");
+		ok(rc != 0, (rc == 0 ? "Connection still alive" : "Connection killed"));
+	}
+
+	return exit_status();
+}