async Response on wasm

[kwek20]

Hi,

Im trying to use the reqwest::Response on wasm, but it has to pass through multiple functions and .awaits.
Unfortunately, Response is not Send/Sync so this makes it difficult to use http calls in the background.

Is there something im missing, or is this only because web_sys::Response isnt Send/sync?
This makes it hard to use with tokio threading for example.

Example the following code:

pub async fn get(&self, url: String, timeout: Duration) -> Result<Response> {
        // client is reqwest::Client
        let mut request_builder = self.client.get(url);
        // Edit the request based on some parameters
        request_builder = self.build_request(request_builder, &node, timeout);
        let start_time = instant::Instant::now();
        let resp = request_builder.send().await?;
        log::debug!(
            "GET: {:?} ms for {} {}",
            start_time.elapsed().as_millis(),
            resp.status(),
            node.url
        );
        Self::parse_response(resp, &node.url).await
}

using this in a task example like this:

let res = self.get(url, timeout).await?;
match res.status() {
    200 => Ok(res.json().await?),
    _ => Err(res.text().await?),
}

gives errors similar to this:
the trait std::marker::Send is not implemented for Rc<RefCell<wasm_bindgen_futures::Inner>> or
within reqwest::Response, the trait Sync is not implemented for *mut u8

I can of course wrap all spawn tasks in a wasm check and spawn local if were in wasm, but thats not really elegant.

Is there a solution for this, or do we need to wait for better threading support?

[seanmonstar]

is this only because web_sys::Response isnt Send/sync?

Yep, that's the reason.

See similar question: #1722

[lostb1t]

An example to make this work would be really helpfull.