fix(canal): fix mysql unsigned medium int (#399)

* fix(canal): fix mysql unsigned medium int

Author: Ryan-Git

canal/canal_test.go

@@ -53,14 +53,16 @@ func (s *canalTestSuite) SetUpSuite(c *C) {
 			id int AUTO_INCREMENT,
 			content blob DEFAULT NULL,
             name varchar(100),
+			mi mediumint(8) NOT NULL DEFAULT 0,
+			umi mediumint(8) unsigned NOT NULL DEFAULT 0,
             PRIMARY KEY(id)
             )ENGINE=innodb;
     `
 
 	s.execute(c, sql)
 
 	s.execute(c, "DELETE FROM test.canal_test")
-	s.execute(c, "INSERT INTO test.canal_test (content, name) VALUES (?, ?), (?, ?), (?, ?)", "1", "a", `\0\ndsfasdf`, "b", "", "c")
+	s.execute(c, "INSERT INTO test.canal_test (content, name, mi, umi) VALUES (?, ?, ?, ?), (?, ?, ?, ?), (?, ?, ?, ?)", "1", "a", 0, 0, `\0\ndsfasdf`, "b", 1, 16777215, "", "c", -1, 1)
 
 	s.execute(c, "SET GLOBAL binlog_format = 'ROW'")
 
@@ -96,6 +98,10 @@ type testEventHandler struct {
 
 func (h *testEventHandler) OnRow(e *RowsEvent) error {
 	log.Infof("OnRow %s %v\n", e.Action, e.Rows)
+	umi, ok := e.Rows[0][4].(uint32) // 4th col is umi. mysqldump gives uint64 instead of uint32
+	if ok && (umi != 0 && umi != 1 && umi != 16777215) {
+		return fmt.Errorf("invalid unsigned medium int %d", umi)
+	}
 	return nil
 }
 
@@ -113,6 +119,7 @@ func (s *canalTestSuite) TestCanal(c *C) {
 	for i := 1; i < 10; i++ {
 		s.execute(c, "INSERT INTO test.canal_test (name) VALUES (?)", fmt.Sprintf("%d", i))
 	}
+	s.execute(c, "INSERT INTO test.canal_test (mi,umi) VALUES (?,?), (?,?), (?,?)", 0, 0, -1, 16777215, 1, 1)
 	s.execute(c, "ALTER TABLE test.canal_test ADD `age` INT(5) NOT NULL AFTER `name`")
 	s.execute(c, "INSERT INTO test.canal_test (name,age) VALUES (?,?)", "d", "18")
 

canal/dump.go

@@ -52,7 +52,7 @@ func (h *dumpParseHandler) Data(db string, table string, values []string) error
 		} else if v == "_binary ''" {
 			vs[i] = []byte{}
 		} else if v[0] != '\'' {
-			if tableInfo.Columns[i].Type == schema.TYPE_NUMBER {
+			if tableInfo.Columns[i].Type == schema.TYPE_NUMBER || tableInfo.Columns[i].Type == schema.TYPE_MEDIUM_INT {
 				n, err := strconv.ParseInt(v, 10, 64)
 				if err != nil {
 					return fmt.Errorf("parse row %v at %d error %v, int expected", values, i, err)

canal/rows.go

@@ -2,7 +2,6 @@ package canal
 
 import (
 	"fmt"
-
 	"github.com/siddontang/go-mysql/replication"
 	"github.com/siddontang/go-mysql/schema"
 )
@@ -41,6 +40,8 @@ func newRowsEvent(table *schema.Table, action string, rows [][]interface{}, head
 	return e
 }
 
+const maxMediumintUnsigned int32 = 16777215
+
 func (r *RowsEvent) handleUnsigned() {
 	// Handle Unsigned Columns here, for binlog replication, we can't know the integer is unsigned or not,
 	// so we use int type but this may cause overflow outside sometimes, so we must convert to the really .
@@ -57,7 +58,18 @@ func (r *RowsEvent) handleUnsigned() {
 			case int16:
 				r.Rows[i][index] = uint16(t)
 			case int32:
-				r.Rows[i][index] = uint32(t)
+				if r.Table.Columns[i].Type == schema.TYPE_MEDIUM_INT {
+					// problem with mediumint is that it's a 3-byte type. There is no compatible golang type to match that.
+					// So to convert from negative to positive we'd need to convert the value manually
+					if i >= 0 {
+						r.Rows[i][index] = uint32(t)
+					} else {
+						r.Rows[i][index] = uint32(maxMediumintUnsigned + t + 1)
+					}
+					return
+				} else {
+					r.Rows[i][index] = uint32(t)
+				}
 			case int64:
 				r.Rows[i][index] = uint64(t)
 			case int:

go.sum

@@ -4,6 +4,7 @@ github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/golang/protobuf v1.3.1 h1:YF8+flBXS5eO826T4nzqPrxfhQThhXl0YzfuUPu4SBg=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
+github.com/pingcap/check v0.0.0-20190102082844-67f458068fc8 h1:USx2/E1bX46VG32FIw034Au6seQ2fY9NEILmNh/UlQg=
 github.com/pingcap/check v0.0.0-20190102082844-67f458068fc8/go.mod h1:B1+S9LNcuMyLH/4HMTViQOJevkGiik3wW2AN9zb2fNQ=
 github.com/pingcap/errors v0.11.0 h1:DCJQB8jrHbQ1VVlMFIrbj2ApScNNotVmkSNplu2yUt4=
 github.com/pingcap/errors v0.11.0/go.mod h1:Oi8TUi2kEtXXLMJk9l1cGmz20kV3TaQ0usTwv5KuLY8=

schema/schema.go

@@ -19,7 +19,7 @@ var HAHealthCheckSchema = "mysql.ha_health_check"
 
 // Different column type
 const (
-	TYPE_NUMBER    = iota + 1 // tinyint, smallint, mediumint, int, bigint, year
+	TYPE_NUMBER    = iota + 1 // tinyint, smallint, int, bigint, year
 	TYPE_FLOAT                // float, double
 	TYPE_ENUM                 // enum
 	TYPE_SET                  // set
@@ -31,6 +31,7 @@ const (
 	TYPE_BIT                  // bit
 	TYPE_JSON                 // json
 	TYPE_DECIMAL              // decimal
+	TYPE_MEDIUM_INT
 )
 
 type TableColumn struct {
@@ -105,6 +106,8 @@ func (ta *Table) AddColumn(name string, columnType string, collation string, ext
 		ta.Columns[index].Type = TYPE_BIT
 	} else if strings.HasPrefix(columnType, "json") {
 		ta.Columns[index].Type = TYPE_JSON
+	} else if strings.Contains(columnType, "mediumint") {
+		ta.Columns[index].Type = TYPE_MEDIUM_INT
 	} else if strings.Contains(columnType, "int") || strings.HasPrefix(columnType, "year") {
 		ta.Columns[index].Type = TYPE_NUMBER
 	} else {