Is there a way to fix this avoiding serde?

[frederikhors]

Hi people! Thanks for your amazing work! I'm new to Rust and I'm using serde only to do this easy thing. I think I can use nanoserde instead but I don't know how.

I'm using serde like this:

use serde::Deserialize;

#[derive(Deserialize, Clone)]
pub struct Player {
    pub team: Team,
}

#[derive(Deserialize, Clone)]
pub struct Team {
    pub id: String,
    // others here
}

// ...

if api_call.status().is_success() {
    match serde_json::from_slice::<Player>(
        &hyper::body::to_bytes(api_call.into_body()).await.unwrap(),
    ) {
        Ok(player) => {
            // use player.team here

            // do something else
        }
        Err(err) => {
            eprintln!("{err}");
        }
    }
}

I tried with:

match nanoserde::DeBin::de_bin::<Player>(
   &hyper::body::to_bytes(api_call.into_body()).await.unwrap(),
) {
  // ...
}

with no luck: it doesn't like the generics.

And tried this too:

let player: Player = nanoserde::DeBin::deserialize_bin(
  &hyper::body::to_bytes(api_call.into_body()).await.unwrap(),
).unwrap();

but this doesn't work, error:

thread 'tokio-runtime-worker' panicked at 'called `Result::unwrap()` on an `Err` value: Bin deserialize error at:8 wanted:1 bytes but max size is 1161', src\cli.rs:85:10

What does this mean?

Is there a way to fix this?

[knickish]

Instead of

use serde::Deserialize;

#[derive(Deserialize, Clone)]
pub struct Player {
    pub team: Team,
}
...

you need to use the appropriate nanoserde type. Something like

use nanoserde::{DeBin, SerBin};

#[derive(DeBin, SerBin, Clone)]
pub struct Player {
   pub team: Team,
}
...

[frederikhors]

Thank you. Of course I changed it. but the problem is still there.

[knickish]

This exact scenario (deserialization of nested structs) is tested extensively already, so I'm not sure how to help with this beyond what I suggested before. You might consider binding the hyper::body::to_bytes(api_call.into_body()).await.unwrap() to a temporary variable to confirm the values look ok, but without a repro I can run there's not much else I can do here. Hope you've been able to solve this.

[knickish]

On second thought, after reading through it again, it looks the endpoint may still have been giving json, and you've attempted to deserialize it as binary.

use nanoserde::{DeJson};

#[derive(DeJson, Clone)]
pub struct Player {
   pub team: Team,
}

with

match nanoserde::DeJson::deserialize_json::<Player>(
   &hyper::body::to_bytes(api_call.into_body()).await.unwrap(),
) {
  // ...
}

might give you what you needed.