forgejo-federation/vendor/github.com/denisenkom/go-mssqldb/tvp_go19.go
zeripath 78e5317242
Update to latest mssqldriver (#7613)
* New driver does not tolerate USE - handle this by closing db and reopening db in the new dbname
2019-07-26 05:10:20 +01:00

231 lines
6.2 KiB
Go
Vendored

// +build go1.9
package mssql
import (
"bytes"
"encoding/binary"
"errors"
"fmt"
"reflect"
"strings"
"time"
)
const (
jsonTag = "json"
tvpTag = "tvp"
skipTagValue = "-"
sqlSeparator = "."
)
var (
ErrorEmptyTVPTypeName = errors.New("TypeName must not be empty")
ErrorTypeSlice = errors.New("TVP must be slice type")
ErrorTypeSliceIsEmpty = errors.New("TVP mustn't be null value")
ErrorSkip = errors.New("all fields mustn't skip")
ErrorObjectName = errors.New("wrong tvp name")
ErrorWrongTyping = errors.New("the number of elements in columnStr and tvpFieldIndexes do not align")
)
//TVP is driver type, which allows supporting Table Valued Parameters (TVP) in SQL Server
type TVP struct {
//TypeName mustn't be default value
TypeName string
//Value must be the slice, mustn't be nil
Value interface{}
}
func (tvp TVP) check() error {
if len(tvp.TypeName) == 0 {
return ErrorEmptyTVPTypeName
}
if !isProc(tvp.TypeName) {
return ErrorEmptyTVPTypeName
}
if sepCount := getCountSQLSeparators(tvp.TypeName); sepCount > 1 {
return ErrorObjectName
}
valueOf := reflect.ValueOf(tvp.Value)
if valueOf.Kind() != reflect.Slice {
return ErrorTypeSlice
}
if valueOf.IsNil() {
return ErrorTypeSliceIsEmpty
}
if reflect.TypeOf(tvp.Value).Elem().Kind() != reflect.Struct {
return ErrorTypeSlice
}
return nil
}
func (tvp TVP) encode(schema, name string, columnStr []columnStruct, tvpFieldIndexes []int) ([]byte, error) {
if len(columnStr) != len(tvpFieldIndexes) {
return nil, ErrorWrongTyping
}
preparedBuffer := make([]byte, 0, 20+(10*len(columnStr)))
buf := bytes.NewBuffer(preparedBuffer)
err := writeBVarChar(buf, "")
if err != nil {
return nil, err
}
writeBVarChar(buf, schema)
writeBVarChar(buf, name)
binary.Write(buf, binary.LittleEndian, uint16(len(columnStr)))
for i, column := range columnStr {
binary.Write(buf, binary.LittleEndian, uint32(column.UserType))
binary.Write(buf, binary.LittleEndian, uint16(column.Flags))
writeTypeInfo(buf, &columnStr[i].ti)
writeBVarChar(buf, "")
}
// The returned error is always nil
buf.WriteByte(_TVP_END_TOKEN)
conn := new(Conn)
conn.sess = new(tdsSession)
conn.sess.loginAck = loginAckStruct{TDSVersion: verTDS73}
stmt := &Stmt{
c: conn,
}
val := reflect.ValueOf(tvp.Value)
for i := 0; i < val.Len(); i++ {
refStr := reflect.ValueOf(val.Index(i).Interface())
buf.WriteByte(_TVP_ROW_TOKEN)
for columnStrIdx, fieldIdx := range tvpFieldIndexes {
field := refStr.Field(fieldIdx)
tvpVal := field.Interface()
valOf := reflect.ValueOf(tvpVal)
elemKind := field.Kind()
if elemKind == reflect.Ptr && valOf.IsNil() {
switch tvpVal.(type) {
case *bool, *time.Time, *int8, *int16, *int32, *int64, *float32, *float64, *int:
binary.Write(buf, binary.LittleEndian, uint8(0))
continue
default:
binary.Write(buf, binary.LittleEndian, uint64(_PLP_NULL))
continue
}
}
if elemKind == reflect.Slice && valOf.IsNil() {
binary.Write(buf, binary.LittleEndian, uint64(_PLP_NULL))
continue
}
cval, err := convertInputParameter(tvpVal)
if err != nil {
return nil, fmt.Errorf("failed to convert tvp parameter row col: %s", err)
}
param, err := stmt.makeParam(cval)
if err != nil {
return nil, fmt.Errorf("failed to make tvp parameter row col: %s", err)
}
columnStr[columnStrIdx].ti.Writer(buf, param.ti, param.buffer)
}
}
buf.WriteByte(_TVP_END_TOKEN)
return buf.Bytes(), nil
}
func (tvp TVP) columnTypes() ([]columnStruct, []int, error) {
val := reflect.ValueOf(tvp.Value)
var firstRow interface{}
if val.Len() != 0 {
firstRow = val.Index(0).Interface()
} else {
firstRow = reflect.New(reflect.TypeOf(tvp.Value).Elem()).Elem().Interface()
}
tvpRow := reflect.TypeOf(firstRow)
columnCount := tvpRow.NumField()
defaultValues := make([]interface{}, 0, columnCount)
tvpFieldIndexes := make([]int, 0, columnCount)
for i := 0; i < columnCount; i++ {
field := tvpRow.Field(i)
tvpTagValue, isTvpTag := field.Tag.Lookup(tvpTag)
jsonTagValue, isJsonTag := field.Tag.Lookup(jsonTag)
if IsSkipField(tvpTagValue, isTvpTag, jsonTagValue, isJsonTag) {
continue
}
tvpFieldIndexes = append(tvpFieldIndexes, i)
if field.Type.Kind() == reflect.Ptr {
v := reflect.New(field.Type.Elem())
defaultValues = append(defaultValues, v.Interface())
continue
}
defaultValues = append(defaultValues, reflect.Zero(field.Type).Interface())
}
if columnCount-len(tvpFieldIndexes) == columnCount {
return nil, nil, ErrorSkip
}
conn := new(Conn)
conn.sess = new(tdsSession)
conn.sess.loginAck = loginAckStruct{TDSVersion: verTDS73}
stmt := &Stmt{
c: conn,
}
columnConfiguration := make([]columnStruct, 0, columnCount)
for index, val := range defaultValues {
cval, err := convertInputParameter(val)
if err != nil {
return nil, nil, fmt.Errorf("failed to convert tvp parameter row %d col %d: %s", index, val, err)
}
param, err := stmt.makeParam(cval)
if err != nil {
return nil, nil, err
}
column := columnStruct{
ti: param.ti,
}
switch param.ti.TypeId {
case typeNVarChar, typeBigVarBin:
column.ti.Size = 0
}
columnConfiguration = append(columnConfiguration, column)
}
return columnConfiguration, tvpFieldIndexes, nil
}
func IsSkipField(tvpTagValue string, isTvpValue bool, jsonTagValue string, isJsonTagValue bool) bool {
if !isTvpValue && !isJsonTagValue {
return false
} else if isTvpValue && tvpTagValue != skipTagValue {
return false
} else if !isTvpValue && isJsonTagValue && jsonTagValue != skipTagValue {
return false
}
return true
}
func getSchemeAndName(tvpName string) (string, string, error) {
if len(tvpName) == 0 {
return "", "", ErrorEmptyTVPTypeName
}
splitVal := strings.Split(tvpName, ".")
if len(splitVal) > 2 {
return "", "", errors.New("wrong tvp name")
}
if len(splitVal) == 2 {
res := make([]string, 2)
for key, value := range splitVal {
tmp := strings.Replace(value, "[", "", -1)
tmp = strings.Replace(tmp, "]", "", -1)
res[key] = tmp
}
return res[0], res[1], nil
}
tmp := strings.Replace(splitVal[0], "[", "", -1)
tmp = strings.Replace(tmp, "]", "", -1)
return "", tmp, nil
}
func getCountSQLSeparators(str string) int {
return strings.Count(str, sqlSeparator)
}