github.com/zhuohuang-hust/src-cbuild@v0.0.0-20230105071821-c7aab3e7c840/api/types/strslice/strslice.go (about)

     1  package strslice
     2  
     3  import "encoding/json"
     4  
     5  // StrSlice represents a string or an array of strings.
     6  // We need to override the json decoder to accept both options.
     7  type StrSlice []string
     8  
     9  // UnmarshalJSON decodes the byte slice whether it's a string or an array of
    10  // strings. This method is needed to implement json.Unmarshaler.
    11  func (e *StrSlice) UnmarshalJSON(b []byte) error {
    12  	if len(b) == 0 {
    13  		// With no input, we preserve the existing value by returning nil and
    14  		// leaving the target alone. This allows defining default values for
    15  		// the type.
    16  		return nil
    17  	}
    18  
    19  	p := make([]string, 0, 1)
    20  	if err := json.Unmarshal(b, &p); err != nil {
    21  		var s string
    22  		if err := json.Unmarshal(b, &s); err != nil {
    23  			return err
    24  		}
    25  		p = append(p, s)
    26  	}
    27  
    28  	*e = p
    29  	return nil
    30  }