Collect tokio tasks and process results

tokio-tasks.rs

use tokio;

fn main() {
    // we want to use this after the async block
    let hosts = ["hostA", "hostB"];

    let rt = tokio::runtime::Runtime::new().unwrap();
    let mut results = Vec::with_capacity(hosts.len());

    rt.block_on(async {
        let mut handles = Vec::with_capacity(hosts.len());
        for host in hosts {
            let cmd = "foobar".to_owned();
            handles.push(tokio::spawn(maybemaybe(
                host.to_owned(),
                "cli_show".to_string(),
                cmd,
            )));
        }
        for handle in handles {
            results.push(handle.await.unwrap());
        }
    });

    for result in results.iter() {
        println!("{:?}", result);
    }

    // do moar stuffs with hosts
    println!("{}", hosts.len());
}

async fn maybemaybe(
    host: String,
    cmd: String,
    fmt: String,
) -> Result<String, Box<dyn std::error::Error + Send + Sync>> {
    Ok(format!("{}-{}-{}", host, cmd, fmt))
}