How does Tokio's Handle::block_on differ from Runtime::block_on?

Question

How does tokio::runtime::Handle.block_on differ to tokio::runtime::Runtime.block_on? The Handle.block_on causes some code to hang whereas the Runtime.block_on works fine.

This is how I create the Handle. The Runtime is the same minus the last 2 lines.

let runtime = runtime::Builder::new_multi_thread()
    .enable_all()
    .build()
    .unwrap()
    .handle() // not needed for Runtime
    .clone(); // ---

Then I call a function which with this:

async fn run(){
    // calls get data
}

self.runtime.block_on(run())

This is the code where it hangs. When running from the Runtime it works fine, with the Handle it hangs at TcpStream::connect().

async fn get_data(addr: String) -> Result<Data> {
    let c = TcpStream::connect(addr.clone()).await?; // hangs here
    let t = get_data_from_connect(c).await?;
    return Ok(t);
}

Answer 1

I fixed this by making sure that the Runtime object does not go out of scope and get dropped. I was under the impression that only the Handle is needed to keep the runtime alive but only the Runtime object itself can.