func()

in internal/apiquery/encoder.go [126:215]

• 75 lines of code
• 21 McCabe index (conditional complexity)

func (e *encoder) newStructTypeEncoder(t reflect.Type) encoderFunc {
	if t.Implements(reflect.TypeOf((*internalparam.FieldLike)(nil)).Elem()) {
		return e.newFieldTypeEncoder(t)
	}

	if t.Implements(reflect.TypeOf((*param.Optional)(nil)).Elem()) {
		return e.newRichFieldTypeEncoder(t)
	}

	for i := 0; i < t.NumField(); i++ {
		if t.Field(i).Type == paramUnionType && t.Field(i).Anonymous {
			return e.newStructUnionTypeEncoder(t)
		}
	}

	encoderFields := []encoderField{}

	// This helper allows us to recursively collect field encoders into a flat
	// array. The parameter `index` keeps track of the access patterns necessary
	// to get to some field.
	var collectEncoderFields func(r reflect.Type, index []int)
	collectEncoderFields = func(r reflect.Type, index []int) {
		for i := 0; i < r.NumField(); i++ {
			idx := append(index, i)
			field := t.FieldByIndex(idx)
			if !field.IsExported() {
				continue
			}
			// If this is an embedded struct, traverse one level deeper to extract
			// the field and get their encoders as well.
			if field.Anonymous {
				collectEncoderFields(field.Type, idx)
				continue
			}
			// If query tag is not present, then we skip, which is intentionally
			// different behavior from the stdlib.
			ptag, ok := parseQueryStructTag(field)
			if !ok {
				continue
			}

			if (ptag.name == "-" || ptag.name == "") && !ptag.inline {
				continue
			}

			dateFormat, ok := parseFormatStructTag(field)
			oldFormat := e.dateFormat
			if ok {
				switch dateFormat {
				case "date-time":
					e.dateFormat = time.RFC3339
				case "date":
					e.dateFormat = "2006-01-02"
				}
			}
			var encoderFn encoderFunc
			if ptag.omitzero {
				typeEncoderFn := e.typeEncoder(field.Type)
				encoderFn = func(key string, value reflect.Value) ([]Pair, error) {
					if value.IsZero() {
						return nil, nil
					}
					return typeEncoderFn(key, value)
				}
			} else {
				encoderFn = e.typeEncoder(field.Type)
			}
			encoderFields = append(encoderFields, encoderField{ptag, encoderFn, idx})
			e.dateFormat = oldFormat
		}
	}
	collectEncoderFields(t, []int{})

	return func(key string, value reflect.Value) (pairs []Pair, err error) {
		for _, ef := range encoderFields {
			var subkey string = e.renderKeyPath(key, ef.tag.name)
			if ef.tag.inline {
				subkey = key
			}

			field := value.FieldByIndex(ef.idx)
			subpairs, suberr := ef.fn(subkey, field)
			if suberr != nil {
				err = suberr
			}
			pairs = append(pairs, subpairs...)
		}
		return
	}
}