Support transaction isolation

Author: Peng Gu

libspectrum/src/protobuf/spectrum.proto

@@ -42,7 +42,9 @@ message SystemVariables {
 
 message Thread {
   int64 id = 1;
-  SystemVariables system_variables = 2;
+  int32 tx_isolation = 2;
+  int32 sql_command = 3;
+  SystemVariables system_variables = 4;
 }
 
 message Row {

libspectrum/src/spectrum_common.cc

@@ -49,6 +49,8 @@ this program; if not, write to the Free Software Foundation, Inc.,
 #include <sql/table.h>
 #include <sql/log.h>
 
+#include <mysql/plugin.h>
+
 #include <grpc/grpc.h>
 #include "spectrum.h"
 
@@ -90,6 +92,8 @@ void spectrum_thread_fill_system_variables(THD *thd, spectrum::Thread *spectrum_
 
 void spectrum_thread_fill(THD *thd, spectrum::Thread *spectrum_thread) {
   spectrum_thread->set_id(thd->spectrum_thread_id);
+  spectrum_thread->set_tx_isolation(thd->tx_isolation);
+  spectrum_thread->set_sql_command(thd_sql_command(thd));
 
   spectrum_thread_fill_system_variables(thd, spectrum_thread);
 }

mysql-test/r/spectrum.result

@@ -1,6 +1,6 @@
-drop database if exists spectrum_test_30;
-create database spectrum_test_30;
-use spectrum_test_30;
+drop database if exists spectrum_test_45;
+create database spectrum_test_45;
+use spectrum_test_45;
 create table employees (id INT PRIMARY KEY, first_name VARCHAR(50) NOT NULL, last_name VARCHAR(50) NOT NULL, hire_date DATE, salary DECIMAL(10, 2));
 insert into employees (id, first_name, last_name, hire_date, salary) VALUES (2, 'Peng', 'Gu', '2024-12-01', 60000.00);
 insert into employees (id, first_name, last_name, hire_date, salary) VALUES (1, 'John', 'Doe', '2024-12-01', 50000.00);
@@ -12,8 +12,15 @@ update employees set salary=555 where id=1;
 select * from employees where id=1;
 id	first_name	last_name	hire_date	salary
 1	John	Doe	2024-12-01	555.00
-use spectrum_test_30;
+use spectrum_test_45;
 select * from employees;
 id	first_name	last_name	hire_date	salary
 1	John	Doe	2024-12-01	555.00
 2	Peng	Gu	2024-12-01	60000.00
+set autocommit = 0;
+update employees set salary=888 where id=1;
+set session transaction isolation level READ COMMITTED;
+select * from employees where id=1;
+id	first_name	last_name	hire_date	salary
+1	John	Doe	2024-12-01	555.00
+commit;

mysql-test/t/spectrum.test

@@ -1,7 +1,7 @@
 connect(compute0,localhost,root,,,3306,/tmp/mysql-spectrum-compute-0.sock);
 connect(compute1,localhost,root,,,3306,/tmp/mysql-spectrum-compute-1.sock);
 
---let $db=spectrum_test_30
+--let $db=spectrum_test_45
 
 connection compute0;
 
@@ -22,3 +22,14 @@ select * from employees where id=1;
 connection compute1;
 eval use $db;
 select * from employees;
+
+connection compute0;
+set autocommit = 0;
+update employees set salary=888 where id=1;
+
+connection compute1;
+set session transaction isolation level READ COMMITTED;
+select * from employees where id=1;
+
+connection compute0;
+commit;

plugin/spectrum_storage/spectrum_storage.cc

@@ -98,6 +98,8 @@ class StorageNodeImpl final : public spectrum::StorageNode::Service {
             spectrum_thread.id(), thd->thread_id()); 
       }
       thd->store_globals();
+      thd->lex->sql_command = (enum_sql_command)spectrum_thread.sql_command();
+      thd->tx_isolation = (enum_tx_isolation)spectrum_thread.tx_isolation();
       thd->variables.option_bits = spectrum_thread.system_variables().option_bits();
       return (thd);
     }