diff options
Diffstat (limited to 'vendor/github.com/labstack/echo/bind.go')
-rw-r--r-- | vendor/github.com/labstack/echo/bind.go | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/vendor/github.com/labstack/echo/bind.go b/vendor/github.com/labstack/echo/bind.go new file mode 100644 index 00000000..f2393ea6 --- /dev/null +++ b/vendor/github.com/labstack/echo/bind.go @@ -0,0 +1,259 @@ +package echo + +import ( + "encoding/json" + "encoding/xml" + "errors" + "fmt" + "net/http" + "reflect" + "strconv" + "strings" +) + +type ( + // Binder is the interface that wraps the Bind method. + Binder interface { + Bind(i interface{}, c Context) error + } + + // DefaultBinder is the default implementation of the Binder interface. + DefaultBinder struct{} + + // BindUnmarshaler is the interface used to wrap the UnmarshalParam method. + BindUnmarshaler interface { + // UnmarshalParam decodes and assigns a value from an form or query param. + UnmarshalParam(param string) error + } +) + +// Bind implements the `Binder#Bind` function. +func (b *DefaultBinder) Bind(i interface{}, c Context) (err error) { + req := c.Request() + if req.Method == GET { + if err = b.bindData(i, c.QueryParams(), "query"); err != nil { + return NewHTTPError(http.StatusBadRequest, err.Error()) + } + return + } + ctype := req.Header.Get(HeaderContentType) + if req.ContentLength == 0 { + return NewHTTPError(http.StatusBadRequest, "Request body can't be empty") + } + switch { + case strings.HasPrefix(ctype, MIMEApplicationJSON): + if err = json.NewDecoder(req.Body).Decode(i); err != nil { + if ute, ok := err.(*json.UnmarshalTypeError); ok { + return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Unmarshal type error: expected=%v, got=%v, offset=%v", ute.Type, ute.Value, ute.Offset)) + } else if se, ok := err.(*json.SyntaxError); ok { + return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Syntax error: offset=%v, error=%v", se.Offset, se.Error())) + } else { + return NewHTTPError(http.StatusBadRequest, err.Error()) + } + } + case strings.HasPrefix(ctype, MIMEApplicationXML): + if err = xml.NewDecoder(req.Body).Decode(i); err != nil { + if ute, ok := err.(*xml.UnsupportedTypeError); ok { + return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Unsupported type error: type=%v, error=%v", ute.Type, ute.Error())) + } else if se, ok := err.(*xml.SyntaxError); ok { + return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Syntax error: line=%v, error=%v", se.Line, se.Error())) + } else { + return NewHTTPError(http.StatusBadRequest, err.Error()) + } + } + case strings.HasPrefix(ctype, MIMEApplicationForm), strings.HasPrefix(ctype, MIMEMultipartForm): + params, err := c.FormParams() + if err != nil { + return NewHTTPError(http.StatusBadRequest, err.Error()) + } + if err = b.bindData(i, params, "form"); err != nil { + return NewHTTPError(http.StatusBadRequest, err.Error()) + } + default: + return ErrUnsupportedMediaType + } + return +} + +func (b *DefaultBinder) bindData(ptr interface{}, data map[string][]string, tag string) error { + typ := reflect.TypeOf(ptr).Elem() + val := reflect.ValueOf(ptr).Elem() + + if typ.Kind() != reflect.Struct { + return errors.New("Binding element must be a struct") + } + + for i := 0; i < typ.NumField(); i++ { + typeField := typ.Field(i) + structField := val.Field(i) + if !structField.CanSet() { + continue + } + structFieldKind := structField.Kind() + inputFieldName := typeField.Tag.Get(tag) + + if inputFieldName == "" { + inputFieldName = typeField.Name + // If tag is nil, we inspect if the field is a struct. + if _, ok := bindUnmarshaler(structField); !ok && structFieldKind == reflect.Struct { + err := b.bindData(structField.Addr().Interface(), data, tag) + if err != nil { + return err + } + continue + } + } + inputValue, exists := data[inputFieldName] + if !exists { + continue + } + + // Call this first, in case we're dealing with an alias to an array type + if ok, err := unmarshalField(typeField.Type.Kind(), inputValue[0], structField); ok { + if err != nil { + return err + } + continue + } + + numElems := len(inputValue) + if structFieldKind == reflect.Slice && numElems > 0 { + sliceOf := structField.Type().Elem().Kind() + slice := reflect.MakeSlice(structField.Type(), numElems, numElems) + for j := 0; j < numElems; j++ { + if err := setWithProperType(sliceOf, inputValue[j], slice.Index(j)); err != nil { + return err + } + } + val.Field(i).Set(slice) + } else { + if err := setWithProperType(typeField.Type.Kind(), inputValue[0], structField); err != nil { + return err + } + } + } + return nil +} + +func setWithProperType(valueKind reflect.Kind, val string, structField reflect.Value) error { + // But also call it here, in case we're dealing with an array of BindUnmarshalers + if ok, err := unmarshalField(valueKind, val, structField); ok { + return err + } + + switch valueKind { + case reflect.Int: + return setIntField(val, 0, structField) + case reflect.Int8: + return setIntField(val, 8, structField) + case reflect.Int16: + return setIntField(val, 16, structField) + case reflect.Int32: + return setIntField(val, 32, structField) + case reflect.Int64: + return setIntField(val, 64, structField) + case reflect.Uint: + return setUintField(val, 0, structField) + case reflect.Uint8: + return setUintField(val, 8, structField) + case reflect.Uint16: + return setUintField(val, 16, structField) + case reflect.Uint32: + return setUintField(val, 32, structField) + case reflect.Uint64: + return setUintField(val, 64, structField) + case reflect.Bool: + return setBoolField(val, structField) + case reflect.Float32: + return setFloatField(val, 32, structField) + case reflect.Float64: + return setFloatField(val, 64, structField) + case reflect.String: + structField.SetString(val) + default: + return errors.New("unknown type") + } + return nil +} + +func unmarshalField(valueKind reflect.Kind, val string, field reflect.Value) (bool, error) { + switch valueKind { + case reflect.Ptr: + return unmarshalFieldPtr(val, field) + default: + return unmarshalFieldNonPtr(val, field) + } +} + +// bindUnmarshaler attempts to unmarshal a reflect.Value into a BindUnmarshaler +func bindUnmarshaler(field reflect.Value) (BindUnmarshaler, bool) { + ptr := reflect.New(field.Type()) + if ptr.CanInterface() { + iface := ptr.Interface() + if unmarshaler, ok := iface.(BindUnmarshaler); ok { + return unmarshaler, ok + } + } + return nil, false +} + +func unmarshalFieldNonPtr(value string, field reflect.Value) (bool, error) { + if unmarshaler, ok := bindUnmarshaler(field); ok { + err := unmarshaler.UnmarshalParam(value) + field.Set(reflect.ValueOf(unmarshaler).Elem()) + return true, err + } + return false, nil +} + +func unmarshalFieldPtr(value string, field reflect.Value) (bool, error) { + if field.IsNil() { + // Initialize the pointer to a nil value + field.Set(reflect.New(field.Type().Elem())) + } + return unmarshalFieldNonPtr(value, field.Elem()) +} + +func setIntField(value string, bitSize int, field reflect.Value) error { + if value == "" { + value = "0" + } + intVal, err := strconv.ParseInt(value, 10, bitSize) + if err == nil { + field.SetInt(intVal) + } + return err +} + +func setUintField(value string, bitSize int, field reflect.Value) error { + if value == "" { + value = "0" + } + uintVal, err := strconv.ParseUint(value, 10, bitSize) + if err == nil { + field.SetUint(uintVal) + } + return err +} + +func setBoolField(value string, field reflect.Value) error { + if value == "" { + value = "false" + } + boolVal, err := strconv.ParseBool(value) + if err == nil { + field.SetBool(boolVal) + } + return err +} + +func setFloatField(value string, bitSize int, field reflect.Value) error { + if value == "" { + value = "0.0" + } + floatVal, err := strconv.ParseFloat(value, bitSize) + if err == nil { + field.SetFloat(floatVal) + } + return err +} |