Using NoneAsEmptyString causes missing values to trigger a DeserializeBodyError

[mu-arch]

I might just be missing something or there is some incompatability somewhere but when I use the

#[serde_as(as = "NoneAsEmptyString")]

feature "" does become None as expected but now my true None values from a missing JSON property trigger a DeserializeBodyError. Suggestions appreciated.

My code:

#[serde_as]
#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
pub struct MailParty {
    pub address: String,
    #[serde_as(as = "NoneAsEmptyString")]
    pub name: Option<String>,
}

[jonasbb]

It is really helpful in understanding the problem, if you can provide a runnable example including the serialized form and the expected outcome.

This is expected behavior of the serde derives. If you use with or deserialize_with on a field, the field becomes mandatory. The as and deserialize_as boil down to with/deserialize_with, so the same applies here. You need to add #[serde(default)] if you want to make the field optional.

[mu-arch]

Thank you very much that solved my problem and I learned something new ^-^ have a great day