From 2e68ba8c6e017b35259b47e3701fd0c5b6bb5624 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20M=C3=A4kel=C3=A4?= <markus.makela@mariadb.com>
Date: Tue, 19 Dec 2017 14:52:10 +0200
Subject: [PATCH] Automatically detect the need for GTID replication

Verifying that the requested replication type matches the one that is
currently in use allows the resetting of the nodes to automatically set up
the correct replication type. This means that a test that invokes
`Mariadb_nodes::require_gtid(true)` before initializing the
TestConnections class is given a replication setup that uses GTID
coordinates instead of file and position.
---
 maxscale-system-test/mariadb_nodes.cpp | 48 ++++++++++++++++++++++----
 1 file changed, 42 insertions(+), 6 deletions(-)

diff --git a/maxscale-system-test/mariadb_nodes.cpp b/maxscale-system-test/mariadb_nodes.cpp
index 6b6cb5806..8d1f0b20a 100644
--- a/maxscale-system-test/mariadb_nodes.cpp
+++ b/maxscale-system-test/mariadb_nodes.cpp
@@ -19,12 +19,12 @@
 
 namespace
 {
-static bool require_gtid = false;
+static bool g_require_gtid = false;
 }
 
 void Mariadb_nodes::require_gtid(bool value)
 {
-    ::require_gtid = value;
+    g_require_gtid = value;
 }
 
 Mariadb_nodes::Mariadb_nodes(const char *pref, const char *test_cwd, bool verbose):
@@ -385,16 +385,24 @@ int Mariadb_nodes::start_replication()
 
     for (int i = 1; i < N; i++)
     {
+        execute_query(nodes[i], "STOP SLAVE;");
+
+        if (g_require_gtid)
+        {
+            execute_query(nodes[i], "SET GLOBAL gtid_slave_pos='0-1-0'");
+        }
+
         // TODO: Reuse the code in sync_slaves() to get the actual file name and position
-        execute_query(nodes[i], "STOP SLAVE;"
+        execute_query(nodes[i],
                       "CHANGE MASTER TO "
                       "MASTER_HOST='%s', MASTER_PORT=%d, "
                       "MASTER_USER='repl', MASTER_PASSWORD='repl', "
-                      "%s;"
-                      "START SLAVE;",
-                      IP_private[0], port[0], require_gtid ?
+                      "%s",
+                      IP_private[0], port[0], g_require_gtid ?
                       "MASTER_USE_GTID=slave_pos" :
                       "MASTER_LOG_FILE='mar-bin.000001', MASTER_LOG_POS=4");
+
+        execute_query(nodes[i], "START SLAVE");
     }
 
     return local_result;
@@ -648,6 +656,33 @@ bool Mariadb_nodes::bad_slave_thread_status(MYSQL *conn, const char *field, int
     return rval;
 }
 
+static bool wrong_replication_type(MYSQL *conn)
+{
+    bool rval = true;
+
+    for (int i = 0; i < 2; i++)
+    {
+        char str[1024] = "";
+
+        if (find_field(conn, "SHOW SLAVE STATUS", "Gtid_IO_Pos", str) == 0)
+        {
+            // If the test requires GTID based replication, Gtid_IO_Pos must not be empty
+            if ((rval = (*str != '\0') != g_require_gtid))
+            {
+                printf("Wrong value for 'Gtid_IO_Pos' (%s), expected it to be %s.\n",
+                       str, g_require_gtid ? "not empty" : "empty");
+            }
+            else
+            {
+                break;
+            }
+        }
+        sleep(1);
+    }
+
+    return rval;
+}
+
 /**
  * @brief multi_source_replication Check if slave is connected to more then one master
  * @param conn MYSQL struct (have to be open)
@@ -715,6 +750,7 @@ int Mariadb_nodes::check_replication()
         }
         else if (bad_slave_thread_status(nodes[i], "Slave_IO_Running", i) ||
                  bad_slave_thread_status(nodes[i], "Slave_SQL_Running", i) ||
+                 wrong_replication_type(nodes[i]) ||
                  multi_source_replication(nodes[i], i))
         {
             res = 1;