add session tracker:SESSION_TRACK_TRANSACTION_CHARACTERISTICS and fix wrong state mapping

server/core/config.cc

@@ -214,6 +214,7 @@ const char *config_service_params[] =
     CN_WEIGHTBY,
     CN_LOG_AUTH_WARNINGS,
     CN_RETRY_ON_FAILURE,
+    CN_SESSION_TRACK_TRX_STATE,
     NULL
 };
 

server/modules/protocol/MySQL/mariadbbackend/mysql_backend.c

@@ -755,9 +755,6 @@ gw_read_and_write(DCB *dcb)
     bool result_collected = false;
     MySQLProtocol *proto = (MySQLProtocol *)dcb->protocol;
 
-    /** Get sesion track info from ok packet and save it to gwbuf properties */
-    mxs_mysql_get_session_track_info(read_buffer, proto->server_capabilities);
-
     if (rcap_type_required(capabilities, RCAP_TYPE_PACKET_OUTPUT) ||
         rcap_type_required(capabilities, RCAP_TYPE_CONTIGUOUS_OUTPUT) ||
         proto->ignore_replies != 0)
@@ -773,6 +770,9 @@ gw_read_and_write(DCB *dcb)
             return 0;
         }
 
+        /** Get sesion track info from ok packet and save it to gwbuf properties */
+        mxs_mysql_get_session_track_info(tmp, proto->server_capabilities);
+
         read_buffer = tmp;
 
         if (rcap_type_required(capabilities, RCAP_TYPE_CONTIGUOUS_OUTPUT) ||

server/modules/protocol/MySQL/mariadbclient/mysql_client.cc

@@ -1894,17 +1894,18 @@ static bool parse_kill_query(char *query, uint64_t *thread_id_out, kill_type_t *
 }
 
 /*
-* Mapping two session tracker's info to mxs_session_trx_state_t
+* Mapping three session tracker's info to mxs_session_trx_state_t
 * SESSION_TRACK_STATE_CHANGE:
-*   When session variable autocommit is changed, it will give a latest value {0|1}
+*   Get lasted autocommit value;
+*   https://dev.mysql.com/worklog/task/?id=6885
 * SESSION_TRACK_TRANSACTION_TYPE:
+*   Get transaction boundaries 
 *   TX_EMPTY                  => SESSION_TRX_INACTIVE
-*   TX_WRITE_TRX              => SESSION_TRX_READ_WRITE
-*   TX_READ_TRX               => SESSION_TRX_READ_ONLY
 *   TX_EXPLICIT | TX_IMPLICIT => SESSION_TRX_ACTIVE
-* refs:
+*   https://dev.mysql.com/worklog/task/?id=6885
-*  1. https://dev.mysql.com/worklog/task/?id=6885
+* SESSION_TRACK_TRANSACTION_CHARACTERISTICS
-*  2. https://dev.mysql.com/worklog/task/?id=6631
+*   Get trx characteristics such as read only, read write, snapshot ...
+*   
 */ 
 static void parse_and_set_trx_state(MXS_SESSION *ses, GWBUF *data)
 {
@@ -1912,11 +1913,12 @@ static void parse_and_set_trx_state(MXS_SESSION *ses, GWBUF *data)
     
     if (autocommit)
     {
-        if (strncasecmp(autocommit, "0", 1) == 0)
+        MXS_DEBUG("autocommit:%s", autocommit);
+        if (strncasecmp(autocommit, "ON", 2) == 0)
         {
             session_set_autocommit(ses, true);
         }
-        if (strncasecmp(autocommit, "1", 1) == 0)
+        if (strncasecmp(autocommit, "OFF", 3) == 0)
         {
             session_set_autocommit(ses, false);
         }   
@@ -1925,23 +1927,29 @@ static void parse_and_set_trx_state(MXS_SESSION *ses, GWBUF *data)
     if (trx_state) 
     {
         mysql_tx_state_t s = parse_trx_state(trx_state);
-        MXS_DEBUG("parsed tx state:%d", s);
 
         if (s == TX_EMPTY) 
         {
             session_set_trx_state(ses, SESSION_TRX_INACTIVE);
         }
-        else if (s & TX_READ_TRX)
-        {
-            session_set_trx_state(ses, SESSION_TRX_READ_ONLY);
-        }
-        else if (s & TX_WRITE_TRX)
-        {
-            session_set_trx_state(ses, SESSION_TRX_READ_WRITE);
-        }
         else if ((s & TX_EXPLICIT) ||  (s & TX_IMPLICIT))
         {
             session_set_trx_state(ses, SESSION_TRX_ACTIVE);
         }
     }
+    char *trx_characteristics = gwbuf_get_property(data, (char *)"trx_characteristics");
+    if (trx_characteristics)
+    {
+        if (strncmp(trx_characteristics, "START TRANSACTION READ ONLY;", 28) == 0)
+        {
+            session_set_trx_state(ses, SESSION_TRX_READ_ONLY);
+        }
+
+        if (strncmp(trx_characteristics, "START TRANSACTION READ WRITE;", 29) == 0)
+        {
+            session_set_trx_state(ses, SESSION_TRX_READ_WRITE);
+        }
+    }
+    MXS_DEBUG("trx state:%s", session_trx_state_to_string(ses->trx_state));
+    MXS_DEBUG("autcommit:%s", session_is_autocommit(ses)?"ON":"OFF");
 }

server/modules/protocol/MySQL/mysql_common.cc

@@ -1777,6 +1777,7 @@ void mxs_mysql_execute_kill_user(MXS_SESSION* issuer, const char* user, kill_typ
  */
 void mxs_mysql_get_session_track_info(GWBUF *buff, uint32_t server_capabilities)
 {
+    ss_dassert(buff);
     char *trx_info, *var_name, *var_value;
     size_t len = GWBUF_LENGTH(buff);
     uint8_t local_buf[len];
@@ -1809,18 +1810,24 @@ void mxs_mysql_get_session_track_info(GWBUF *buff, uint32_t server_capabilities)
                     enum_session_state_type type = (enum enum_session_state_type)mxs_leint_consume(&ptr);
                     switch (type)
                     {
-                        case SESSION_TRACK_SYSTEM_VARIABLES:
+                        case SESSION_TRACK_STATE_CHANGE:
                         case SESSION_TRACK_SCHEMA:
                         case SESSION_TRACK_GTIDS:
-                        case SESSION_TRACK_TRANSACTION_CHARACTERISTICS:
                             ptr += mxs_leint_consume(&ptr);
                             break;
-                        case SESSION_TRACK_STATE_CHANGE:
+                        case SESSION_TRACK_TRANSACTION_CHARACTERISTICS:
+                            mxs_leint_consume(&ptr); //length
+                            var_value = mxs_lestr_consume_dup(&ptr);
+                            gwbuf_add_property(buff, (char *)"trx_characteristics", var_value);
+                            MXS_FREE(var_value);
+                            break;
+                        case SESSION_TRACK_SYSTEM_VARIABLES:
                             mxs_leint_consume(&ptr); //lenth 
                             // system variables like autocommit, schema, charset ... 
                             var_name = mxs_lestr_consume_dup(&ptr);
                             var_value = mxs_lestr_consume_dup(&ptr);
                             gwbuf_add_property(buff, var_name, var_value);
+                            MXS_DEBUG("SESSION_TRACK_SYSTEM_VARIABLES, name:%s, value:%s", var_name, var_value);
                             MXS_FREE(var_name);
                             MXS_FREE(var_value);
                             break;