How to deserialize a field that contains JSON?

Imagine I need to parse the following body:

{
  "input": "{\"type\":\"id\",\"name\":\"DNI\"}"
}

As you can see, the input field contains a JSON but in "string".

I have the following Rust struct

pub struct Input {
  input: String
}

and then I can deserialize it, but I would like to have it defined like this:

pub struct InputType {
  type: String,
  name: String
}
pub struct Input {
  input: InputType
}

any idea how can I do it?

Use deserialize_with like so:

#[derive(Deserialize)]
struct InputType {
    #[serde(rename = "type")]
    typ: String,
    name: String,
}

#[derive(Deserialize)]
struct Input {
    #[serde(deserialize_with = "deserialize_input")]
    input: InputType,
}

fn deserialize_input<'de, D: Deserializer<'de>>(d: D) -> Result<InputType, D::Error> {
    let text = String::deserialize(d)?;
    serde_json::from_str(&text).map_err(serde::de::Error::custom)
}

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