Why Response::bytes consume self?

[StackOverflowExcept1on]

Let's say you want to set up logging (in case of some rate limits), but it's not possible or you'll have to manually copy implementation of json() method.

https://docs.rs/reqwest/latest/reqwest/struct.Response.html#method.json

[harshagarwalnyu]

HTTP response bodies are streams - once you read through them, they're gone. There's no way to rewind a network socket, so bytes(), json(), text() etc. all consume self to make that explicit in the type system.

For your logging use case, just read the bytes first and then work with those:

let response = client.get(&url).send().await?;
let status = response.status();
let headers = response.headers().clone();
let bytes = response.bytes().await?;

// log whatever you need
if status == StatusCode::TOO_MANY_REQUESTS {
    let body_str = String::from_utf8_lossy(&bytes);
    tracing::warn!("Rate limited: {}", body_str);
}

// deserialize from the bytes you already have
let data: MyType = serde_json::from_slice(&bytes)?;

The headers().clone() is there because headers are also tied to the response - if you need them after consuming the body, grab them first. Status code is Copy so that's fine on its own.