sql/mysql: fix mysql information_schema escaping

ariga · Mar 3, 2022 · 4fd209c · 4fd209c
1 parent 2860b39
commit 4fd209c
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Showing 3 changed files with 29 additions and 31 deletions.
diff --git a/sql/mysql/driver.go b/sql/mysql/driver.go
@@ -142,13 +142,17 @@ func (d *conn) gteV(w string) bool { return d.compareV(w) >= 0 }
 // ltV reports if the connection version is < w.
 func (d *conn) ltV(w string) bool { return d.compareV(w) == -1 }
 
-// MySQL standard unescape field function from its codebase:
-// https://github.com/mysql/mysql-server/blob/8.0/sql/dd/impl/utils.cc
+// unescape strings with backslashes returned
+// for SQL expressions from information schema.
 func unescape(s string) string {
 	var b strings.Builder
-	for i, c := range s {
-		if c != '\\' || i+1 < len(s) && s[i+1] != '\\' && s[i+1] != '=' && s[i+1] != ';' {
-			b.WriteRune(c)
+	for i := 0; i < len(s); i++ {
+		switch c := s[i]; {
+		case c != '\\' || i == len(s)-1:
+			b.WriteByte(c)
+		case s[i+1] == '\'', s[i+1] == '\\':
+			b.WriteByte(s[i+1])
+			i++
 		}
 	}
 	return b.String()

diff --git a/sql/mysql/inspect.go b/sql/mysql/inspect.go
@@ -335,12 +335,7 @@ func (i *inspect) addIndexes(s *schema.Schema, rows *sql.Rows) error {
 		part := &schema.IndexPart{SeqNo: seqno, Desc: desc.Bool}
 		switch {
 		case sqlx.ValidString(expr):
-			part.X = &schema.RawExpr{X: expr.String}
-			// Functional indexes may need to be extracted from 'SHOW CREATE',
-			// because INFORMATION_SCHEMA returns them escaped and they cannot
-			// be inlined this way.
-			s := putShow(t)
-			s.indexes[idx] = append(s.indexes[idx], len(idx.Parts))
+			part.X = &schema.RawExpr{X: unescape(expr.String)}
 		case sqlx.ValidString(column):
 			part.C, ok = t.Column(column.String)
 			if !ok {
@@ -407,6 +402,7 @@ func (i *inspect) checks(ctx context.Context, s *schema.Schema) error {
 			Expr: unescape(clause.String),
 		}
 		if i.mariadb() {
+			check.Expr = clause.String
 			// In MariaDB, JSON is an alias to LONGTEXT. For versions >= 10.4.3, the CHARSET and COLLATE set to utf8mb4
 			// and a CHECK constraint is automatically created for the column as well (i.e. JSON_VALID(`<C>`)). However,
 			// we expect tools like Atlas and Ent to manually add this CHECK for older versions of MariaDB.
@@ -425,10 +421,6 @@ func (i *inspect) checks(ctx context.Context, s *schema.Schema) error {
 			check.Attrs = append(check.Attrs, &Enforced{V: false})
 		}
 		t.Attrs = append(t.Attrs, check)
-		// CHECK constraints need to be extracted from 'SHOW CREATE', because
-		// INFORMATION_SCHEMA returns them escaped and they cannot be used on
-		// 'CREATE' this way.
-		putShow(t).checks = true
 	}
 	return rows.Err()
 }
@@ -475,7 +467,6 @@ func (i *inspect) showCreate(ctx context.Context, s *schema.Schema) error {
 		if err := i.setAutoInc(st, t); err != nil {
 			return err
 		}
-		// TODO(a8m): setChecks, setIndexExpr from CREATE statement.
 	}
 	return nil
 }
@@ -797,10 +788,6 @@ type (
 		schema.Attr
 		// AUTO_INCREMENT value to due missing value in information_schema.
 		auto *AutoIncrement
-		// checks expressions formatted differently from exist in 'SHOW CREATE'.
-		checks bool
-		// indexes that contain expressions.
-		indexes map[*schema.Index][]int
 	}
 )
 
@@ -810,7 +797,7 @@ func putShow(t *schema.Table) *showTable {
 			return s
 		}
 	}
-	s := &showTable{indexes: make(map[*schema.Index][]int)}
+	s := &showTable{}
 	t.Attrs = append(t.Attrs, s)
 	return s
 }

diff --git a/sql/mysql/inspect_test.go b/sql/mysql/inspect_test.go
@@ -178,15 +178,8 @@ func TestDriver_InspectTable(t *testing.T) {
 | table  | CONSTRAINT_NAME  | CHECK_CLAUSE                              |  ENFORCED  |
 +--------+------------------+-------------------------------------------+------------+
 | users  | jsonc            | json_valid(` + "`jsonc`" + `)             |  YES       |
+| users  | users_chk_1      | longtext <> '\'\'""'                      |  YES       |
 +--------+------------------+-------------------------------------------+------------+
-`))
-				m.ExpectQuery(sqltest.Escape("SHOW CREATE TABLE `public`.`users`")).
-					WillReturnRows(sqltest.Rows(`
-+-------+---------------------------------------------------------------------------------------------------------------------------------------------+
-| Table | Create Table                                                                                                                                |
-+-------+---------------------------------------------------------------------------------------------------------------------------------------------+
-| users | CREATE TABLE users (id bigint NOT NULL AUTO_INCREMENT) ENGINE=InnoDB AUTO_INCREMENT=55834574848 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin |
-+-------+---------------------------------------------------------------------------------------------------------------------------------------------+
 `))
 			},
 			expect: func(require *require.Assertions, t *schema.Table, err error) {
@@ -198,6 +191,10 @@ func TestDriver_InspectTable(t *testing.T) {
 					{Name: "longtext", Type: &schema.ColumnType{Raw: "longtext", Type: &schema.StringType{T: "longtext"}}},
 					{Name: "jsonc", Type: &schema.ColumnType{Raw: "json", Type: &schema.JSONType{T: "json"}}},
 				}, t.Columns)
+				require.EqualValues([]schema.Attr{
+					&schema.Check{Name: "jsonc", Expr: "json_valid(`jsonc`)"},
+					&schema.Check{Name: "users_chk_1", Expr: `longtext <> '\'\'""'`},
+				}, t.Attrs)
 			},
 		},
 		{
@@ -605,7 +602,11 @@ func TestDriver_InspectTable(t *testing.T) {
 +-------------------+-------------------+-------------------------------------------+------------+
 | TABLE_NAME        | CONSTRAINT_NAME   | CHECK_CLAUSE                              |  ENFORCED  |
 +-------------------+-------------------+-------------------------------------------+------------+
-| users             | users_chk_1       | (` + "`c6`" + ` <>_latin1\'foo\\\'s\')    |  YES       |
+| users             | users_chk_1       | (` + "`c6`" + ` <> _latin1\'foo\\\'s\')   |  YES       |
+| users             | users_chk_2       | (c1 <> _latin1\'dev/atlas\')              |  YES       |
+| users             | users_chk_3       | (c1 <> _latin1\'a\\\'b""\')               |  YES       |
+| users             | users_chk_4       | (c1 <> in (_latin1\'usa\',_latin1\'uk\')) |  YES       |
+| users             | users_chk_5       | (c1 <> _latin1\'\\\\\\\\\\\'\\\'\')       |  YES       |
 +-------------------+-------------------+-------------------------------------------+------------+
 `))
 				m.ExpectQuery(sqltest.Escape("SHOW CREATE TABLE `public`.`users`")).
@@ -626,7 +627,13 @@ func TestDriver_InspectTable(t *testing.T) {
 					{Name: "c1", Type: &schema.ColumnType{Raw: "int", Type: &schema.IntegerType{T: "int"}}},
 				}
 				require.EqualValues(columns, t.Columns)
-				require.EqualValues([]schema.Attr{&schema.Check{Name: "users_chk_1", Expr: "(`c6` <>_latin1\\'foo\\'s\\')"}, &CreateStmt{S: "CREATE TABLE users()"}}, t.Attrs)
+				require.EqualValues([]schema.Attr{
+					&schema.Check{Name: "users_chk_1", Expr: "(`c6` <> _latin1'foo\\'s')"},
+					&schema.Check{Name: "users_chk_2", Expr: "(c1 <> _latin1'dev/atlas')"},
+					&schema.Check{Name: "users_chk_3", Expr: `(c1 <> _latin1'a\'b""')`},
+					&schema.Check{Name: "users_chk_4", Expr: `(c1 <> in (_latin1'usa',_latin1'uk'))`},
+					&schema.Check{Name: "users_chk_5", Expr: `(c1 <> _latin1'\\\\\'\'')`},
+				}, t.Attrs)
 			},
 		},
 	}