support driver.Valuer type in Struct and interpolate methods

Author: huandu

interpolate.go

@@ -4,7 +4,9 @@
 package sqlbuilder
 
 import (
+	"database/sql/driver"
 	"fmt"
+	"reflect"
 	"strconv"
 	"time"
 	"unicode"
@@ -389,78 +391,13 @@ func encodeValue(buf []byte, arg interface{}, flavor Flavor) ([]byte, error) {
 	case nil:
 		buf = append(buf, "NULL"...)
 
-	case bool:
-		if v {
-			buf = append(buf, "TRUE"...)
+	case driver.Valuer:
+		if val, err := v.Value(); err != nil {
+			return nil, err
 		} else {
-			buf = append(buf, "FALSE"...)
+			return encodeValue(buf, val, flavor)
 		}
 
-	case int:
-		buf = strconv.AppendInt(buf, int64(v), 10)
-
-	case int8:
-		buf = strconv.AppendInt(buf, int64(v), 10)
-
-	case int16:
-		buf = strconv.AppendInt(buf, int64(v), 10)
-
-	case int32:
-		buf = strconv.AppendInt(buf, int64(v), 10)
-
-	case int64:
-		buf = strconv.AppendInt(buf, v, 10)
-
-	case uint:
-		buf = strconv.AppendUint(buf, uint64(v), 10)
-
-	case uint8:
-		buf = strconv.AppendUint(buf, uint64(v), 10)
-
-	case uint16:
-		buf = strconv.AppendUint(buf, uint64(v), 10)
-
-	case uint32:
-		buf = strconv.AppendUint(buf, uint64(v), 10)
-
-	case uint64:
-		buf = strconv.AppendUint(buf, v, 10)
-
-	case float32:
-		buf = strconv.AppendFloat(buf, float64(v), 'g', -1, 32)
-
-	case float64:
-		buf = strconv.AppendFloat(buf, v, 'g', -1, 64)
-
-	case []byte:
-		if v == nil {
-			buf = append(buf, "NULL"...)
-			break
-		}
-
-		switch flavor {
-		case MySQL:
-			buf = append(buf, "_binary"...)
-			buf = quoteStringValue(buf, *(*string)(unsafe.Pointer(&v)), flavor)
-
-		case PostgreSQL:
-			buf = append(buf, "E'\\\\x"...)
-			buf = appendHex(buf, v)
-			buf = append(buf, "'::bytea"...)
-
-		case SQLite:
-			buf = append(buf, "X'"...)
-			buf = appendHex(buf, v)
-			buf = append(buf, '\'')
-
-		case SQLServer:
-			buf = append(buf, "0x"...)
-			buf = appendHex(buf, v)
-		}
-
-	case string:
-		buf = quoteStringValue(buf, v, flavor)
-
 	case time.Time:
 		if v.IsZero() {
 			buf = append(buf, "'0000-00-00'"...)
@@ -492,7 +429,103 @@ func encodeValue(buf []byte, arg interface{}, flavor Flavor) ([]byte, error) {
 		buf = quoteStringValue(buf, v.String(), flavor)
 
 	default:
-		return nil, ErrInterpolateUnsupportedArgs
+		primative := reflect.ValueOf(arg)
+
+		switch k := primative.Kind(); k {
+		case reflect.Bool:
+			if primative.Bool() {
+				buf = append(buf, "TRUE"...)
+			} else {
+				buf = append(buf, "FALSE"...)
+			}
+
+		case reflect.Int:
+			buf = strconv.AppendInt(buf, primative.Int(), 10)
+
+		case reflect.Int8:
+			buf = strconv.AppendInt(buf, primative.Int(), 10)
+
+		case reflect.Int16:
+			buf = strconv.AppendInt(buf, primative.Int(), 10)
+
+		case reflect.Int32:
+			buf = strconv.AppendInt(buf, primative.Int(), 10)
+
+		case reflect.Int64:
+			buf = strconv.AppendInt(buf, primative.Int(), 10)
+
+		case reflect.Uint:
+			buf = strconv.AppendUint(buf, primative.Uint(), 10)
+
+		case reflect.Uint8:
+			buf = strconv.AppendUint(buf, primative.Uint(), 10)
+
+		case reflect.Uint16:
+			buf = strconv.AppendUint(buf, primative.Uint(), 10)
+
+		case reflect.Uint32:
+			buf = strconv.AppendUint(buf, primative.Uint(), 10)
+
+		case reflect.Uint64:
+			buf = strconv.AppendUint(buf, primative.Uint(), 10)
+
+		case reflect.Float32:
+			buf = strconv.AppendFloat(buf, primative.Float(), 'g', -1, 32)
+
+		case reflect.Float64:
+			buf = strconv.AppendFloat(buf, primative.Float(), 'g', -1, 64)
+
+		case reflect.String:
+			buf = quoteStringValue(buf, primative.String(), flavor)
+
+		case reflect.Slice, reflect.Array:
+			if k == reflect.Slice && primative.IsNil() {
+				buf = append(buf, "NULL"...)
+				break
+			}
+
+			if elem := primative.Type().Elem(); elem.Kind() != reflect.Uint8 {
+				return nil, ErrInterpolateUnsupportedArgs
+			}
+
+			var data []byte
+
+			// Bytes() will panic if primative is an array and cannot be addressed.
+			// Copy all bytes to data as a fallback.
+			if k == reflect.Array && !primative.CanAddr() {
+				l := primative.Len()
+				data = make([]byte, l)
+
+				for i := 0; i < l; i++ {
+					data[i] = byte(primative.Index(i).Uint())
+				}
+			} else {
+				data = primative.Bytes()
+			}
+
+			switch flavor {
+			case MySQL:
+				buf = append(buf, "_binary"...)
+				buf = quoteStringValue(buf, *(*string)(unsafe.Pointer(&data)), flavor)
+
+			case PostgreSQL:
+				buf = append(buf, "E'\\\\x"...)
+				buf = appendHex(buf, data)
+				buf = append(buf, "'::bytea"...)
+
+			case SQLite:
+				buf = append(buf, "X'"...)
+				buf = appendHex(buf, data)
+				buf = append(buf, '\'')
+
+			case SQLServer:
+				buf = append(buf, "0x"...)
+				buf = appendHex(buf, data)
+			}
+
+		default:
+			return nil, ErrInterpolateUnsupportedArgs
+		}
 	}
 
 	return buf, nil

interpolate_test.go

@@ -1,23 +1,34 @@
 package sqlbuilder
 
 import (
+	"database/sql/driver"
+	"errors"
 	"strconv"
 	"testing"
 	"time"
 
 	"github.com/huandu/go-assert"
 )
 
+type errorValuer int
+
+var ErrErrorValuer = errors.New("error valuer")
+
+func (v errorValuer) Value() (driver.Value, error) {
+	return 0, ErrErrorValuer
+}
+
 func TestFlavorInterpolate(t *testing.T) {
 	a := assert.New(t)
 	dt := time.Date(2019, 4, 24, 12, 23, 34, 123456789, time.FixedZone("CST", 8*60*60)) // 2019-04-24 12:23:34.987654321 CST
 	_, errOutOfRange := strconv.ParseInt("12345678901234567890", 10, 32)
+	byteArr := [...]byte{'f', 'o', 'o'}
 	cases := []struct {
-		flavor Flavor
-		sql    string
-		args   []interface{}
-		query  string
-		err    error
+		Flavor Flavor
+		SQL    string
+		Args   []interface{}
+		Query  string
+		Err    error
 	}{
 		{
 			MySQL,
@@ -39,6 +50,11 @@ func TestFlavorInterpolate(t *testing.T) {
 			"SELECT '\\'?', \"\\\"?\", `\\`?`, \\?", []interface{}{MySQL},
 			"SELECT '\\'?', \"\\\"?\", `\\`?`, \\'MySQL'", nil,
 		},
+		{
+			MySQL,
+			"SELECT ?", []interface{}{byteArr},
+			"SELECT _binary'foo'", nil,
+		},
 		{
 			MySQL,
 			"SELECT ?", nil,
@@ -49,6 +65,16 @@ func TestFlavorInterpolate(t *testing.T) {
 			"SELECT ?", []interface{}{complex(1, 2)},
 			"", ErrInterpolateUnsupportedArgs,
 		},
+		{
+			MySQL,
+			"SELECT ?", []interface{}{[]complex128{complex(1, 2)}},
+			"", ErrInterpolateUnsupportedArgs,
+		},
+		{
+			MySQL,
+			"SELECT ?", []interface{}{errorValuer(1)},
+			"", ErrErrorValuer,
+		},
 
 		{
 			PostgreSQL,
@@ -141,9 +167,9 @@ func TestFlavorInterpolate(t *testing.T) {
 
 	for idx, c := range cases {
 		a.Use(&idx, &c)
-		query, err := c.flavor.Interpolate(c.sql, c.args)
+		query, err := c.Flavor.Interpolate(c.SQL, c.Args)
 
-		a.Equal(query, c.query)
-		a.Assert(err == c.err || err.Error() == c.err.Error())
+		a.Equal(query, c.Query)
+		a.Assert(err == c.Err || err.Error() == c.Err.Error())
 	}
 }

struct.go

@@ -5,6 +5,7 @@ package sqlbuilder
 
 import (
 	"bytes"
+	"database/sql/driver"
 	"math"
 	"reflect"
 	"regexp"
@@ -36,6 +37,8 @@ const (
 
 var optRegex = regexp.MustCompile(`(?P<` + optName + `>\w+)(\((?P<` + optParams + `>.*)\))?`)
 
+var typeOfSQLDriverValuer = reflect.TypeOf((*driver.Valuer)(nil)).Elem()
+
 // Struct represents a struct type.
 //
 // All methods in Struct are thread-safe.
@@ -179,7 +182,7 @@ func (s *Struct) UpdateForTag(table string, tag string, value interface{}) *Upda
 				continue
 			}
 		} else {
-			val = dereferencedValue(val)
+			val = dereferencedFieldValue(val)
 		}
 
 		data := val.Interface()
@@ -237,7 +240,7 @@ func (s *Struct) buildColsAndValuesForTag(ib *InsertBuilder, tag string, value .
 
 	for _, item := range value {
 		v := reflect.ValueOf(item)
-		v = dereferencedValue(v)
+		v = dereferencedFieldValue(v)
 
 		if v.Type() == s.structType {
 			vs = append(vs, v)
@@ -265,7 +268,7 @@ func (s *Struct) buildColsAndValuesForTag(ib *InsertBuilder, tag string, value .
 				nilCnt++
 			}
 
-			val = dereferencedValue(val)
+			val = dereferencedFieldValue(val)
 
 			if val.IsValid() {
 				values[i] = append(values[i], val.Interface())
@@ -485,6 +488,18 @@ func dereferencedValue(v reflect.Value) reflect.Value {
 	return v
 }
 
+func dereferencedFieldValue(v reflect.Value) reflect.Value {
+	for k := v.Kind(); k == reflect.Ptr || k == reflect.Interface; k = v.Kind() {
+		if v.Type().Implements(typeOfSQLDriverValuer) {
+			break
+		}
+
+		v = v.Elem()
+	}
+
+	return v
+}
+
 // isEmptyValue checks if v is zero.
 // Following code is borrowed from `IsZero` method in `reflect.Value` since Go 1.13.
 func isEmptyValue(v reflect.Value) bool {

struct_test.go

@@ -4,6 +4,7 @@
 package sqlbuilder
 
 import (
+	"database/sql/driver"
 	"fmt"
 	"testing"
 	"time"
@@ -811,6 +812,37 @@ func TestStructFieldAs(t *testing.T) {
 	a.Equal(sql, `UPDATE t SET t1 = ?, t2 = ?, t4 = ?`)
 }
 
+type structImplValuer int
+
+func (v *structImplValuer) Value() (driver.Value, error) {
+	return *v * 2, nil
+}
+
+type structContainsValuer struct {
+	F1 string
+	F2 *structImplValuer
+}
+
+func TestStructFieldsImplValuer(t *testing.T) {
+	a := assert.New(t)
+	st := NewStruct(new(structContainsValuer))
+	f1 := "foo"
+	f2 := structImplValuer(100)
+
+	sql, args := st.Update("t", structContainsValuer{
+		F1: f1,
+		F2: &f2,
+	}).BuildWithFlavor(MySQL)
+
+	a.Equal(sql, "UPDATE t SET F1 = ?, F2 = ?")
+	a.Equal(args[0], f1)
+	a.Equal(args[1], &f2)
+
+	result, err := MySQL.Interpolate(sql, args)
+	a.NilError(err)
+	a.Equal(result, "UPDATE t SET F1 = 'foo', F2 = 200")
+}
+
 func SomeOtherMapper(string) string {
 	return ""
 }