MXS-1503: Add test case

Added test case that checks that session commands are properly executed.

maxscale-system-test/CMakeLists.txt

@@ -596,6 +596,9 @@ add_test_executable(mxs1476.cpp mxs1476 mxs1476 LABELS GALERA_BACKEND)
 # https://jira.mariadb.org/browse/MXS-1503
 add_test_executable(mxs1503_master_reconnection.cpp mxs1503_master_reconnection mxs1503_master_reconnection LABELS REPL_BACKEND)
 
+# Master reconnection with session commands
+add_test_executable(mxs1503_queued_sescmd.cpp mxs1503_queued_sescmd mxs1503_master_reconnection LABELS REPL_BACKEND)
+
 # MXS-1509: Show correct server state for multisource replication
 # https://jira.mariadb.org/browse/MXS-1509
 add_test_executable(mxs1509.cpp mxs1509 mxs1509 LABELS REPL_BACKEND)

maxscale-system-test/mxs1503_queued_sescmd.cpp

@@ -0,0 +1,58 @@
+/**
+ * MXS-1503: Test master reconnection with session command history
+ *
+ * https://jira.mariadb.org/browse/MXS-1503
+ */
+#include "testconnections.h"
+#include <vector>
+#include <iostream>
+#include <functional>
+
+using std::cout;
+using std::endl;
+
+int main(int argc, char** argv)
+{
+    TestConnections test(argc, argv);
+
+    auto query = [&test](std::string q)
+    {
+        return execute_query_silent(test.maxscales->conn_rwsplit[0], q.c_str());
+    };
+
+    auto check_result = [&test](std::string name, std::string res)
+    {
+        std::string query = "SELECT " + name;
+        char value[1024];
+        return find_field(test.maxscales->conn_rwsplit[0], query.c_str(), name.c_str(), value) == 0 &&
+               res == value;
+    };
+
+    test.maxscales->connect();
+    test.assert(query("DROP TABLE IF EXISTS test.t1;") == 0, "DROP TABLE should work.");
+    test.assert(query("CREATE TABLE test.t1 (id INT);") == 0, "CREATE TABLE should work.");
+
+    // Execute session commands so that the history is not empty
+    cout << "Setting user variables" << endl;
+    test.assert(query("SET @a = 1") == 0, "First session command should work.");
+    test.assert(query("USE test") == 0, "Second session command should work.");
+    test.assert(query("SET @b = 2") == 0, "Third session command should work.");
+
+    // Block the master to trigger reconnection
+    cout << "Blocking master" << endl;
+    test.repl->block_node(0);
+    sleep(10);
+    cout << "Unblocking master" << endl;
+    test.repl->unblock_node(0);
+    sleep(10);
+
+    // Check that inserts work
+    cout << "Selecting user variables" << endl;
+    test.set_timeout(15);
+    test.assert(query("INSERT INTO test.t1 VALUES (1)") == 0, "Write should work after unblocking master");
+    test.assert(check_result("@a", "1"), "@a should be 1");
+    test.assert(check_result("@b", "2"), "@b should be 2");
+    query("DROP TABLE test.t1");
+
+    return test.global_result;
+}