Tutorial Spawning Section Not Working

[Android789515]

I got to the very end of the section and I'm not getting any output on the server. The first section (accepting sockets) I got to work just fine.

I even tried copying and pasting the exact code (for main.rs) and it's not working.

src/examples/hello-redis.rs:

use mini_redis::{client, Result};

#[tokio::main]
async fn main() -> Result<()> {
    let mut client = client::connect("127.0.0.1:6379").await?;

    client.set("hello", "world".into()).await?;

    let value = client.get("hello").await?;

    println!("The value for hello is {:?}.", value);

    Ok(())
}

src/main.rs:

use tokio::net::TcpListener;

#[tokio::main]
async fn main() {
    let listener = TcpListener::bind("127.0.0.1:6379").await.unwrap();

    loop {
        let (socket, _) = listener.accept().await.unwrap();
        // A new task is spawned for each inbound socket. The socket is
        // moved to the new task and processed there.
        tokio::spawn(async move {
            process(socket).await;
        });
    }
}
use tokio::net::TcpStream;
use mini_redis::{Connection, Frame};

async fn process(socket: TcpStream) {
    use mini_redis::Command::{self, Get, Set};
    use std::collections::HashMap;

    // A hashmap is used to store data
    let mut db = HashMap::new();

    // Connection, provided by `mini-redis`, handles parsing frames from
    // the socket
    let mut connection = Connection::new(socket);

    // Use `read_frame` to receive a command from the connection.
    while let Some(frame) = connection.read_frame().await.unwrap() {
        let response = match Command::from_frame(frame).unwrap() {
            Set(cmd) => {
                // The value is stored as `Vec<u8>`
                db.insert(cmd.key().to_string(), cmd.value().to_vec());
                Frame::Simple("OK".to_string())
            }
            Get(cmd) => {
                if let Some(value) = db.get(cmd.key()) {
                    // `Frame::Bulk` expects data to be of type `Bytes`. This
                    // type will be covered later in the tutorial. For now,
                    // `&Vec<u8>` is converted to `Bytes` using `into()`.
                    Frame::Bulk(value.clone().into())
                } else {
                    Frame::Null
                }
            }
            cmd => panic!("unimplemented {:?}", cmd),
        };

        // Write the response to the client
        connection.write_frame(&response).await.unwrap();
    }
}

cargo run:

/home/untitled1/rust-lernin/redis-clone
───────────────────────────╮ No clue
                           ╰─────────> cargo run
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.03s
     Running `target/debug/redis-clone`

cargo run --example hello-redis:

/home/untitled1/rust-lernin/redis-clone
───────────────────────────╮
                           ╰─────────> cargo run --example hello-redis
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.02s
     Running `target/debug/examples/hello-redis`
The value for hello is Some(b"world").

After running the example I get nothing on the server:

/home/untitled1/rust-lernin/redis-clone
───────────────────────────╮ No clue
                           ╰─────────> cargo run
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.03s
     Running `target/debug/redis-clone`

[Darksonn]

I don't see any println! in the server code, so I would not expect any output. Have you tried adding a println! statement?

[Android789515]

The process isn't returning anything to print. This is a problem with the docs. They don't include a println statement in the main function nor does the example produce anything to print anyway. Otherwise I could await the handle in the main function and print that.

[Darksonn]

Can you elaborate on what the problem is? Do you want us to add printlns to the tutorial so that it's easier to see whether it's working? As far as I can tell from what you shared, the code does work.

[Android789515]

Can you elaborate on what the problem is? Do you want us to add printlns to the tutorial so that it's easier to see whether it's working? As far as I can tell from what you shared, the code does work.

Basically the docs are saying there should be an output but the code doesn't match that:

There's nothing in the code that will print:

got value from the server; result=Some(b"world")