34 lines
792 B
Go
34 lines
792 B
Go
package helper
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import "encoding/json"
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type NullString struct {
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String string
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IsNull bool
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}
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// Serialization
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func (ns NullString) MarshalJSON() ([]byte, error) {
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// If Valid is true, return the JSON serialization result of String.
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if ns.IsNull {
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return []byte(`"` + ns.String + `"`), nil
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}
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// If Valid is false, return the serialization result of null.
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return []byte("null"), nil
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}
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// Deserialization
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func (ns *NullString) UnmarshalJSON(data []byte) error {
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// If data is null, set Valid to false and String to an empty string.
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if string(data) == "null" {
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ns.String, ns.IsNull = "", false
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return nil
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}
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// Otherwise, deserialize data to String and set Valid to true.
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if err := json.Unmarshal(data, &ns.String); err != nil {
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return err
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}
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ns.IsNull = true
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return nil
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}
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