Does serde_with support post processor, or there is another way to do this?

[Magicloud]

I need to use a web interface giving a JSON object. Converting to Rust, would be:

struct Obj {
  field_a: Vec<String>,
  field_b: Vec<String>,
  field_c: Option<Vec<String>>,
}

The interface actually uses empty Vec when there is nothing for the field, but for reason unknown, the author made field_c null when there is nothing. It looks really inconsistent.

So I wonder if I could do something like:

#[serde_as(as = "Option<Vec<String>>", de-post-processor = "unwrap_or_default")]
field_c: Vec<String>

[jonasbb]

I think your use case is covered by DefaultOnNull.

A general post-processing like this is not really feasible outside serde_derive. Functions are not generic types, so you cannot have a PostProcess<unwrap_or_default> or similar.

[Magicloud]

Thank you.