refactor(examples): change file-sharing from async-std to tokio

Closes: #5180
Related: #4449.

Pull-Request: #5191.

examples/file-sharing/Cargo.toml

@@ -10,11 +10,10 @@ release = false
 
 [dependencies]
 serde = { version = "1.0", features = ["derive"] }
-async-std = { version = "1.12", features = ["attributes"] }
+tokio = { version = "1.36.0", features = ["full"] }
 clap = { version = "4.4.16", features = ["derive"] }
-either = "1.9"
 futures = "0.3.30"
-libp2p = { path = "../../libp2p", features = [ "async-std", "cbor", "dns", "kad", "noise", "macros", "request-response", "tcp", "websocket", "yamux"] }
+libp2p = { path = "../../libp2p", features = [ "tokio", "cbor", "dns", "kad", "noise", "macros", "request-response", "tcp", "websocket", "yamux"] }
 tracing = "0.1.37"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 void = "1.0.2"

examples/file-sharing/src/main.rs

@@ -22,8 +22,8 @@
 
 mod network;
 
-use async_std::task::spawn;
 use clap::Parser;
+use tokio::task::spawn;
 
 use futures::prelude::*;
 use futures::StreamExt;
@@ -33,7 +33,7 @@ use std::io::Write;
 use std::path::PathBuf;
 use tracing_subscriber::EnvFilter;
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn Error>> {
     let _ = tracing_subscriber::fmt()
         .with_env_filter(EnvFilter::from_default_env())

examples/file-sharing/src/network.rs

@@ -1,5 +1,6 @@
 use futures::channel::{mpsc, oneshot};
 use futures::prelude::*;
+use futures::StreamExt;
 
 use libp2p::{
     core::Multiaddr,
@@ -40,7 +41,7 @@ pub(crate) async fn new(
     let peer_id = id_keys.public().to_peer_id();
 
     let mut swarm = libp2p::SwarmBuilder::with_existing_identity(id_keys)
-        .with_async_std()
+        .with_tokio()
         .with_tcp(
             tcp::Config::default(),
             noise::Config::new,
@@ -197,8 +198,8 @@ impl EventLoop {
 
     pub(crate) async fn run(mut self) {
         loop {
-            futures::select! {
-                event = self.swarm.next() => self.handle_event(event.expect("Swarm stream to be infinite.")).await  ,
+            tokio::select! {
+                event = self.swarm.select_next_some() => self.handle_event(event).await,
                 command = self.command_receiver.next() => match command {
                     Some(c) => self.handle_command(c).await,
                     // Command channel closed, thus shutting down the network event loop.