stream.peer_addr() & auth_query (#575)

* Don't unwrap stream.peer_addr()

https://github.com/postgresml/pgcat/pull/562 (same code)
(another lines changed)

* auth_query (real sample)

# single quote need
auth_query="SELECT usename, passwd FROM pg_shadow WHERE usename='$1'"

src/client.rs

@@ -117,7 +117,15 @@ pub async fn client_entrypoint(
     log_client_connections: bool,
 ) -> Result<(), Error> {
     // Figure out if the client wants TLS or not.
-    let addr = stream.peer_addr().unwrap();
+    let addr = match stream.peer_addr() {
+        Ok(addr) => addr,
+        Err(err) => {
+            return Err(Error::SocketError(format!(
+                "Failed to get peer address: {:?}",
+                err
+            )));
+        }
+    };
 
     match get_startup::<TcpStream>(&mut stream).await {
         // Client requested a TLS connection.