docs: improve docs about tokio::main

tracing/mainmatter-workshop/src/middleware.rs

@@ -1,10 +1,10 @@
 use std::time::Instant;
 
-use actix_web::HttpMessage as _;
 use actix_web::{
     body::MessageBody,
     dev::{ServiceRequest, ServiceResponse},
     http::header::{HeaderName, HeaderValue},
+    HttpMessage as _,
 };
 use actix_web_lab::middleware::Next;
 use tracing_actix_web::RequestId;

websockets/autobahn/src/main.rs

@@ -32,6 +32,7 @@ impl StreamHandler<Result<ws::Message, ws::ProtocolError>> for AutobahnWebSocket
     }
 }
 
+// the actor-based WebSocket examples REQUIRE `actix_web::main` for actor support
 #[actix_web::main]
 async fn main() -> std::io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));

websockets/chat-actorless/src/main.rs

@@ -47,7 +47,6 @@ async fn chat_ws(
     Ok(res)
 }
 
-// note that the actor-based WebSocket examples would NOT work under `tokio::main`
 #[tokio::main(flavor = "current_thread")]
 async fn main() -> io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));

websockets/chat-broker/src/main.rs

@@ -16,6 +16,7 @@ async fn chat_ws(req: HttpRequest, stream: web::Payload) -> Result<impl Responde
     ws::start(WsChatSession::default(), &req, stream)
 }
 
+// the actor-based WebSocket examples REQUIRE `actix_web::main` for actor support
 #[actix_web::main]
 async fn main() -> std::io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));

websockets/chat-tcp/src/main.rs

@@ -220,6 +220,7 @@ impl WsChatSession {
     }
 }
 
+// the actor-based WebSocket examples REQUIRE `actix_web::main` for actor support
 #[actix_web::main]
 async fn main() -> std::io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));

websockets/chat/src/main.rs

@@ -45,6 +45,7 @@ async fn get_count(count: web::Data<AtomicUsize>) -> impl Responder {
     format!("Visitors: {current_count}")
 }
 
+// the actor-based WebSocket examples REQUIRE `actix_web::main` for actor support
 #[actix_web::main]
 async fn main() -> std::io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));

websockets/echo-actorless/src/main.rs

@@ -65,7 +65,6 @@ async fn broadcast_ws(
     Ok(res)
 }
 
-// note that the actor-based WebSocket examples would NOT work under `tokio::main`
 #[tokio::main(flavor = "current_thread")]
 async fn main() -> io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));

websockets/echo/src/main.rs

@@ -18,6 +18,7 @@ async fn echo_ws(req: HttpRequest, stream: web::Payload) -> Result<HttpResponse,
     ws::start(MyWebSocket::new(), &req, stream)
 }
 
+// the actor-based WebSocket examples REQUIRE `actix_web::main` for actor support
 #[actix_web::main]
 async fn main() -> std::io::Result<()> {
     env_logger::init_from_env(env_logger::Env::new().default_filter_or("info"));