event_loop.next()

[benidi]

Hello everyone,
I can't poll the event_loop, what I'm doing wrong here?

I want to use this code:

        match connection_result {
            Ok((session, event_loop)) => {
                let handle = event_loop.spawn();
                let session_await_result = session.wait_for_connection().await;
                tokio::task::spawn(async move {
                    // Using `next` requires the futures_util package.
                    while let Some(evt) = event_loop.next() {
                        match evt {
                            Ok(SessionPollResult::ConnectionLost(status)) => { /* connection lost */
                            }
                            Ok(SessionPollResult::Reconnected(mode)) => { /* connection established */
                            }
                            Ok(SessionPollResult::ReconnectFailed(status)) => { /* connection attempt failed */
                            }
                            Err(e) => { /* Exhausted connect retries, the stream will exit now */ }
                            _ => { /* Other events */ }
                        }
                    }
                });
                self.opc_session = Some(session);
                Ok(())
            }
            Err(status_code) => {
                error!("Could not create OPC Session: {}", status_code);
                return Err(());
            }
        }

but i get this error:
the method next exists for struct SessionEventLoop, but its trait bounds were not satisfied
the following trait bounds were not satisfied:
opcua::opcua_client::SessionEventLoop: futures::Stream
which is required by opcua::opcua_client::SessionEventLoop: futures::StreamExt

i have this import:
use futures::stream::StreamExt;

[einarmo]

You must call enter on the event loop to convert it to a stream that you can consume with next.

[benidi]

This was not working for me... i am in a #[actix_web::main] context, is this the problem?

[einarmo]

Maybe? How did it fail?

[benidi]

i think the session is not running anymore.
This is the last log entry from the opcua:
session:1 create_monitored_items, 57 items created
After this there is nothing from the opcua in the log. As if the session is not running anymore.

[einarmo]

That sounds unrelated, did something panic?

[benidi]

no, i don't see anything.
I will test this outside of my project to rule out that it could otherwise be a problem. I will come back to you. Thank you