tokio-tutorial-mini-redis: Add proper error handling

Keep unwrapping accept() and Mutex failures, these are early/unlikely enough
to be okay to crash.

diff --git a/tokio-tutorial-mini-redis/src/bin/server.rs b/tokio-tutorial-mini-redis/src/bin/server.rs
index 441ea1881c90007acb12897eb0fb89a060948b5c..962c923dab5c13b17c34a50504c71a324f2733bf 100644 (file)
--- a/tokio-tutorial-mini-redis/src/bin/server.rs
+++ b/tokio-tutorial-mini-redis/src/bin/server.rs
@@ -1,4 +1,5 @@
 use std::collections::HashMap;
+use std::error::Error;
 use std::sync::{Arc, Mutex};
 
 use bytes::Bytes;
@@ -19,19 +20,26 @@ async fn main() {
     let db: Db = Arc::new(Mutex::new(HashMap::new()));
 
     loop {
-        // The second item contains the IP and port of the new connection
-        let (socket, addr) = listener.accept().await.unwrap();
-        log::debug!("got connection from {:?}", addr);
-        let db_i = db.clone();
-        tokio::spawn(async move { process(socket, db_i).await });
+        match listener.accept().await {
+            Ok((socket, addr)) => {
+                log::debug!("got connection from {:?}", addr);
+                let db_i = db.clone();
+                tokio::spawn(async move {
+                    if let Err(e) = process(socket, db_i).await {
+                        log::warn!("failed: {:?}", e);
+                    }
+                });
+            },
+            Err(e) => log::warn!("Failed to accept connection: {}", e),
+        };
     }
 }
 
-async fn process(socket: TcpStream, db: Db) {
+async fn process(socket: TcpStream, db: Db) -> Result<(), Box<dyn Error + Send + Sync>> {
     let mut connection = Connection::new(socket);
 
-    while let Some(frame) = connection.read_frame().await.unwrap() {
-        let response = match Command::from_frame(frame).unwrap() {
+    while let Some(frame) = connection.read_frame().await? {
+        let response = match Command::from_frame(frame)? {
             Set(cmd) => {
                 // The value is stored as `Vec<u8>`
                 db.lock().unwrap().insert(cmd.key().to_string(), cmd.value().clone());
@@ -51,6 +59,7 @@ async fn process(socket: TcpStream, db: Db) {
         };
 
         // Write the response to the client
-        connection.write_frame(&response).await.unwrap();
+        connection.write_frame(&response).await?;
     }
+    Ok(())
 }