Provide context for raw service examples

Cargo.toml

@@ -17,7 +17,6 @@ tokio-util = { version = "0.7.0", features = ["codec", "net"] }
 bytes = "1.1.0"
 futures = "0.3.21"
 async-trait = "0.1.53"
-async-stream = "0.3.3"
 pin-project = "1.0.10"
 sync_wrapper = "0.1.1"
 dyn-clone = "1.0.5"
@@ -27,3 +26,6 @@ env_logger = "0.9.0"
 log = "0.4.16"
 coap-lite = "0.9.0"
 dashmap = "5.2.0"
+
+[dev-dependencies]
+async-stream = "0.3.3"

examples/non_piggybacked_response.rs → examples/custom_non_piggybacked_service.rs

@@ -20,6 +20,11 @@ async fn main() -> Result<(), FatalServerError> {
     server.serve(NonPiggybackedService::default()).await
 }
 
+/// Highly customized service that manually implements advanced features like not using
+/// a piggy backed response + ack in order to allow very slow running responses to not
+/// confuse clients.  These features will eventually make their way into the app-based
+/// approach (if they aren't already there!), but this provides a good example of what is
+/// possible with the lowest level API.
 #[derive(Default, Clone)]
 struct NonPiggybackedService {}
 

examples/service_mutability.rs → examples/custom_service.rs

@@ -33,6 +33,9 @@ impl Default for CountingService {
     }
 }
 
+/// It is possible to do all the raw packet handling yourself if you have some very sophisticated
+/// use case not currently covered by the generic App-based handler.  Pull requests welcome,
+/// however!
 impl PacketHandler<SocketAddr> for CountingService {
     fn handle(
         &self,