Add json (un)marshal supportv1.0.0

This allows to use optionals for fields of structs which are marshalled
or unmarshalled to or from JavaScript object notation (JSON).

1 files changed, 35 insertions, 0 deletions

diff --git a/optional/json.go b/optional/json.go
new file mode 100644
index 0000000..23aa780
--- /dev/null
+++ b/optional/json.go
@@ -0,0 +1,35 @@
+package optional
+
+import (
+	"encoding/json"
+)
+
+func (o *Optional[T]) UnmarshalJSON(data []byte) error {
+	var Buffer *T
+
+	err := json.Unmarshal(data, &Buffer)
+	if err != nil {
+		return err
+	}
+
+	if Buffer == nil {
+		var empty T
+		o.Value = empty
+		o.Exists = false
+		return nil
+	}
+
+	o.Value = *Buffer
+	o.Exists = true
+	return nil
+}
+
+func (o Optional[T]) MarshalJSON() ([]byte, error) {
+	var Buffer *T
+
+	if o.Exists {
+		Buffer = &o.Value
+	}
+
+	return json.Marshal(Buffer)
+}