started query cancellation

src/main.rs

@@ -7,12 +7,17 @@ extern crate tokio;
 use bb8::Pool;
 use tokio::net::TcpListener;
 
+use std::collections::HashMap;
+use std::sync::{Arc, Mutex};
+
 mod client;
 mod errors;
 mod messages;
 mod pool;
 mod server;
 
+type ClientServerMap = Arc<Mutex<HashMap<i32, i32>>>;
+
 #[tokio::main]
 async fn main() {
     println!("> Welcome to PgRabbit");