Module serde_with::rust::default_on_null [−][src]
Deserialize default value if encountering null
.
One use case are JSON APIs in which the null
value represents some default state.
This adapter allows to turn the null
directly into the Default
value of the type.
Converting to serde_as
The same functionality can be more clearly expressed via DefaultOnNull
and using the serde_as
macro.
It can be combined with other convertes as shown.
#[serde_as] #[derive(Deserialize)] struct A { #[serde_as(as = "DefaultOnNull")] value: u32, #[serde_as(as = "DefaultOnNull<DisplayFromStr>")] value2: u32, }
Examples
#[derive(Deserialize)] struct A { #[serde(deserialize_with = "serde_with::rust::default_on_null::deserialize")] value: u32, } let a: A = serde_json::from_str(r#"{"value": 123}"#).unwrap(); assert_eq!(123, a.value); let a: A = serde_json::from_str(r#"{"value": null}"#).unwrap(); assert_eq!(0, a.value); // String is invalid type assert!(serde_json::from_str::<A>(r#"{"value": "123"}"#).is_err());
Functions
deserialize | Deserialize T and return the |
serialize | Serialize value with the default serializer |