Merge pull request #8275 from planetscale/online-ddl-vrepl-enum-to-va…

…rchar

Online DDL/Vreplication suite: support ENUM->VARCHAR/TEXT type change

go.sum

@@ -693,6 +693,7 @@ github.com/spyzhov/ajson v0.4.2 h1:JMByd/jZApPKDvNsmO90X2WWGbmT2ahDFp73QhZbg3s=
 github.com/spyzhov/ajson v0.4.2/go.mod h1:63V+CGM6f1Bu/p4nLIN8885ojBdt88TbLoSFzyqMuVA=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.2.0 h1:Hbg2NidpLE8veEBkEZTL3CvlkUIVzuU9jDplZO54c48=
 github.com/stretchr/objx v0.2.0/go.mod h1:qt09Ya8vawLte6SNmTgCsAVtYtaKzEcn8ATUoHMkEqE=
 github.com/stretchr/testify v0.0.0-20151208002404-e3a8ff8ce365/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=

go/test/endtoend/onlineddl/vrepl_suite/testdata/enum-to-varchar-rename/after_columns

@@ -0,0 +1 @@
+id, i, e2

go/test/endtoend/onlineddl/vrepl_suite/testdata/enum-to-varchar-rename/alter

@@ -0,0 +1 @@
+change e e2 varchar(32) not null default ''

go/test/endtoend/onlineddl/vrepl_suite/testdata/enum-to-varchar-rename/before_columns

@@ -0,0 +1 @@
+id, i, e

go/test/endtoend/onlineddl/vrepl_suite/testdata/enum-to-varchar-rename/create.sql

@@ -0,0 +1,26 @@
+drop table if exists onlineddl_test;
+create table onlineddl_test (
+  id int auto_increment,
+  i int not null,
+  e enum('red', 'green', 'blue', 'orange') null default null collate 'utf8_bin',
+  primary key(id)
+) auto_increment=1;
+
+insert into onlineddl_test values (null, 7, 'red');
+
+drop event if exists onlineddl_test;
+delimiter ;;
+create event onlineddl_test
+  on schedule every 1 second
+  starts current_timestamp
+  ends current_timestamp + interval 60 second
+  on completion not preserve
+  enable
+  do
+begin
+  insert into onlineddl_test values (null, 11, 'red');
+  insert into onlineddl_test values (null, 13, 'green');
+  insert into onlineddl_test values (null, 17, 'blue');
+  set @last_insert_id := last_insert_id();
+  update onlineddl_test set e='orange' where id = @last_insert_id;
+end ;;

go/test/endtoend/onlineddl/vrepl_suite/testdata/enum-to-varchar/alter

@@ -0,0 +1 @@
+change e e varchar(32) not null default ''

go/test/endtoend/onlineddl/vrepl_suite/testdata/enum-to-varchar/create.sql

@@ -0,0 +1,26 @@
+drop table if exists onlineddl_test;
+create table onlineddl_test (
+  id int auto_increment,
+  i int not null,
+  e enum('red', 'green', 'blue', 'orange') null default null collate 'utf8_bin',
+  primary key(id)
+) auto_increment=1;
+
+insert into onlineddl_test values (null, 7, 'red');
+
+drop event if exists onlineddl_test;
+delimiter ;;
+create event onlineddl_test
+  on schedule every 1 second
+  starts current_timestamp
+  ends current_timestamp + interval 60 second
+  on completion not preserve
+  enable
+  do
+begin
+  insert into onlineddl_test values (null, 11, 'red');
+  insert into onlineddl_test values (null, 13, 'green');
+  insert into onlineddl_test values (null, 17, 'blue');
+  set @last_insert_id := last_insert_id();
+  update onlineddl_test set e='orange' where id = @last_insert_id;
+end ;;

go/vt/schema/parser.go

@@ -19,8 +19,10 @@ package schema
 import (
 	"fmt"
 	"regexp"
+	"strconv"
 	"strings"
 
+	"vitess.io/vitess/go/textutil"
 	"vitess.io/vitess/go/vt/sqlparser"
 )
 
@@ -51,6 +53,8 @@ var (
 	}
 	createTableRegexp     = regexp.MustCompile(`(?s)(?i)(CREATE\s+TABLE\s+)` + "`" + `([^` + "`" + `]+)` + "`" + `(\s*[(].*$)`)
 	revertStatementRegexp = regexp.MustCompile(`(?i)^revert\s+([\S]*)$`)
+
+	enumValuesRegexp = regexp.MustCompile("(?i)^enum[(](.*)[)]$")
 )
 
 // ReplaceTableNameInCreateTableStatement returns a modified CREATE TABLE statement, such that the table name is replaced with given name.
@@ -101,3 +105,35 @@ func legacyParseRevertUUID(sql string) (uuid string, err error) {
 	}
 	return uuid, nil
 }
+
+// ParseEnumValues parses the comma delimited part of an enum column definition
+func ParseEnumValues(enumColumnType string) string {
+	if submatch := enumValuesRegexp.FindStringSubmatch(enumColumnType); len(submatch) > 0 {
+		return submatch[1]
+	}
+	return enumColumnType
+}
+
+// ParseEnumTokens parses the comma delimited part of an enum column definition and
+// returns the (unquoted) text values
+func ParseEnumTokens(enumValues string) []string {
+	enumValues = ParseEnumValues(enumValues)
+	tokens := textutil.SplitDelimitedList(enumValues)
+	for i := range tokens {
+		if strings.HasPrefix(tokens[i], `'`) && strings.HasSuffix(tokens[i], `'`) {
+			tokens[i] = strings.Trim(tokens[i], `'`)
+		}
+	}
+	return tokens
+}
+
+// ParseEnumTokensMap parses the comma delimited part of an enum column definition
+// and returns a map where ["1"] is the first token, and ["<n>"] is th elast token
+func ParseEnumTokensMap(enumValues string) map[string]string {
+	tokens := ParseEnumTokens(enumValues)
+	tokensMap := map[string]string{}
+	for i, token := range tokens {
+		tokensMap[strconv.Itoa(i+1)] = token
+	}
+	return tokensMap
+}

go/vt/schema/parser_test.go

@@ -109,3 +109,58 @@ func TestLegacyParseRevertUUID(t *testing.T) {
 		assert.Error(t, err)
 	}
 }
+
+func TestParseEnumValues(t *testing.T) {
+	{
+		inputs := []string{
+			`enum('x-small','small','medium','large','x-large')`,
+			`ENUM('x-small','small','medium','large','x-large')`,
+			`'x-small','small','medium','large','x-large'`,
+		}
+		for _, input := range inputs {
+			enumValues := ParseEnumValues(input)
+			assert.Equal(t, `'x-small','small','medium','large','x-large'`, enumValues)
+		}
+	}
+	{
+		inputs := []string{
+			``,
+			`abc`,
+			`func('x-small','small','medium','large','x-large')`,
+		}
+		for _, input := range inputs {
+			enumValues := ParseEnumValues(input)
+			assert.Equal(t, input, enumValues)
+		}
+	}
+}
+
+func TestParseEnumTokens(t *testing.T) {
+	inputs := []string{
+		`enum('x-small','small','medium','large','x-large')`,
+		`'x-small','small','medium','large','x-large'`,
+	}
+	for _, input := range inputs {
+		enumTokens := ParseEnumTokens(input)
+		expect := []string{"x-small", "small", "medium", "large", "x-large"}
+		assert.Equal(t, expect, enumTokens)
+	}
+}
+
+func TestParseEnumTokensMap(t *testing.T) {
+	inputs := []string{
+		`enum('x-small','small','medium','large','x-large')`,
+		`'x-small','small','medium','large','x-large'`,
+	}
+	for _, input := range inputs {
+		enumTokensMap := ParseEnumTokensMap(input)
+		expect := map[string]string{
+			"1": "x-small",
+			"2": "small",
+			"3": "medium",
+			"4": "large",
+			"5": "x-large",
+		}
+		assert.Equal(t, expect, enumTokensMap)
+	}
+}