| package hscan |
| |
| import ( |
| "fmt" |
| "reflect" |
| "strings" |
| "sync" |
| ) |
| |
| // structMap contains the map of struct fields for target structs |
| // indexed by the struct type. |
| type structMap struct { |
| m sync.Map |
| } |
| |
| func newStructMap() *structMap { |
| return new(structMap) |
| } |
| |
| func (s *structMap) get(t reflect.Type) *structSpec { |
| if v, ok := s.m.Load(t); ok { |
| return v.(*structSpec) |
| } |
| |
| spec := newStructSpec(t, "redis") |
| s.m.Store(t, spec) |
| return spec |
| } |
| |
| //------------------------------------------------------------------------------ |
| |
| // structSpec contains the list of all fields in a target struct. |
| type structSpec struct { |
| m map[string]*structField |
| } |
| |
| func (s *structSpec) set(tag string, sf *structField) { |
| s.m[tag] = sf |
| } |
| |
| func newStructSpec(t reflect.Type, fieldTag string) *structSpec { |
| numField := t.NumField() |
| out := &structSpec{ |
| m: make(map[string]*structField, numField), |
| } |
| |
| for i := 0; i < numField; i++ { |
| f := t.Field(i) |
| |
| tag := f.Tag.Get(fieldTag) |
| if tag == "" || tag == "-" { |
| continue |
| } |
| |
| tag = strings.Split(tag, ",")[0] |
| if tag == "" { |
| continue |
| } |
| |
| // Use the built-in decoder. |
| out.set(tag, &structField{index: i, fn: decoders[f.Type.Kind()]}) |
| } |
| |
| return out |
| } |
| |
| //------------------------------------------------------------------------------ |
| |
| // structField represents a single field in a target struct. |
| type structField struct { |
| index int |
| fn decoderFunc |
| } |
| |
| //------------------------------------------------------------------------------ |
| |
| type StructValue struct { |
| spec *structSpec |
| value reflect.Value |
| } |
| |
| func (s StructValue) Scan(key string, value string) error { |
| field, ok := s.spec.m[key] |
| if !ok { |
| return nil |
| } |
| if err := field.fn(s.value.Field(field.index), value); err != nil { |
| t := s.value.Type() |
| return fmt.Errorf("cannot scan redis.result %s into struct field %s.%s of type %s, error-%s", |
| value, t.Name(), t.Field(field.index).Name, t.Field(field.index).Type, err.Error()) |
| } |
| return nil |
| } |