Unable to send response.

[nurmohammed840]

I am trying to send large payload (409600+ bytes)

For some reason I was unable to send payload, I think there is something wrong with h2 crate ?

Here is my code:

pub struct Sender {
    pub inner: h2::SendStream<Bytes>,
}

impl Sender {
    #[inline]
    pub async fn write(&mut self, data: impl Into<Bytes>) -> Result<()> {
        let mut bytes: Bytes = data.into();
        while !bytes.is_empty() {
            let len = bytes.len();
            self.inner.reserve_capacity(len);
            match poll_fn(|cx| self.inner.poll_capacity(cx)).await {
                None => return Err(h2::Error::from(h2::Reason::CANCEL)),
                Some(nbytes) => {
                    let data = bytes.split_to(nbytes?.min(len));
                    self.inner.send_data(data, false)?;
                }
            }
        }
        Ok(())
    }

    #[inline]
    pub fn end(mut self) -> Result<()> {
        self.inner.send_data(Bytes::new(), true)
    }
}

Here is the full example

On first iteration poll_capacity return Ready(Ok(409600)), But poll_capacity doesn't resolve on second iteration,

Using wireshark, I notice that server didn't response with any application data at all...

[seanmonstar]

You need to be polling the connection actively. That is what sends the actual frames.

If you use hyper, it will help take care of these things for you.

[nurmohammed840]

I think doc should include this information.

Thanks!

[seanmonstar]

The docs do mention it:

The Connection instance is used to manage connection state. The caller is required to call either Connection::accept or Connection::poll_close in order to advance the connection state. Simply operating on SendStream or RecvStream will have no effect unless the connection state is advanced.