gf/internal/structs/structs_field.go
2021-05-17 19:59:34 +08:00

122 lines
3.3 KiB
Go

// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
package structs
import "reflect"
// Tag returns the value associated with key in the tag string. If there is no
// such key in the tag, Tag returns the empty string.
func (f *Field) Tag(key string) string {
return f.Field.Tag.Get(key)
}
// TagLookup returns the value associated with key in the tag string.
// If the key is present in the tag the value (which may be empty)
// is returned. Otherwise the returned value will be the empty string.
// The ok return value reports whether the value was explicitly set in
// the tag string. If the tag does not have the conventional format,
// the value returned by Lookup is unspecified.
func (f *Field) TagLookup(key string) (value string, ok bool) {
return f.Field.Tag.Lookup(key)
}
// IsEmbedded returns true if the given field is an anonymous field (embedded)
func (f *Field) IsEmbedded() bool {
return f.Field.Anonymous
}
// IsExported returns true if the given field is exported.
func (f *Field) IsExported() bool {
return f.Field.PkgPath == ""
}
// Name returns the name of the given field
func (f *Field) Name() string {
return f.Field.Name
}
// Type returns the type of the given field
func (f *Field) Type() Type {
return Type{
Type: f.Field.Type,
}
}
// Kind returns the reflect.Kind for Value of Field `f`.
func (f *Field) Kind() reflect.Kind {
return f.Value.Kind()
}
// OriginalKind retrieves and returns the original reflect.Kind for Value of Field `f`.
func (f *Field) OriginalKind() reflect.Kind {
var (
kind = f.Value.Kind()
value = f.Value
)
for kind == reflect.Ptr {
value = value.Elem()
kind = value.Kind()
}
return kind
}
// FieldMap retrieves and returns struct field as map[name/tag]*Field from `pointer`.
//
// The parameter `pointer` should be type of struct/*struct.
//
// The parameter `priority` specifies the priority tag array for retrieving from high to low.
// If it's given `nil`, it returns map[name]*Field, of which the `name` is attribute name.
//
// The parameter `recursive` specifies the whether retrieving the fields recursively if the attribute
// is an embedded struct.
//
// Note that it only retrieves the exported attributes with first letter up-case from struct.
func FieldMap(pointer interface{}, priority []string, recursive bool) (map[string]*Field, error) {
fields, err := getFieldValues(pointer)
if err != nil {
return nil, err
}
var (
tagValue = ""
mapField = make(map[string]*Field)
)
for _, field := range fields {
// Only retrieve exported attributes.
if !field.IsExported() {
continue
}
tagValue = ""
for _, p := range priority {
tagValue = field.Tag(p)
if tagValue != "" && tagValue != "-" {
break
}
}
tempField := field
tempField.TagValue = tagValue
if tagValue != "" {
mapField[tagValue] = tempField
} else {
if recursive && field.IsEmbedded() {
m, err := FieldMap(field.Value, priority, recursive)
if err != nil {
return nil, err
}
for k, v := range m {
if _, ok := mapField[k]; !ok {
tempV := v
mapField[k] = tempV
}
}
} else {
mapField[field.Name()] = tempField
}
}
}
return mapField, nil
}