add initial connection pool (#53)

tests/pool.rs

@@ -0,0 +1,30 @@
+use mini_redis::{client, pool, server};
+use std::net::SocketAddr;
+use tokio::net::TcpListener;
+use tokio::task::JoinHandle;
+
+/// A basic "hello world" style test. A server instance is started in a
+/// background task. A client instance is then established and inserted into the pool, set and get
+/// commands are then sent to the server. The response is then evaluated
+#[tokio::test]
+async fn pool_key_value_get_set() {
+    let (addr, _) = start_server().await;
+
+    let client = client::connect(addr).await.unwrap();
+    let pool = pool::create(client);
+    let mut client = pool.get_connection();
+
+    client.set("hello", "world".into()).await.unwrap();
+
+    let value = client.get("hello").await.unwrap().unwrap();
+    assert_eq!(b"world", &value[..])
+}
+
+async fn start_server() -> (SocketAddr, JoinHandle<mini_redis::Result<()>>) {
+    let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let addr = listener.local_addr().unwrap();
+
+    let handle = tokio::spawn(async move { server::run(listener, tokio::signal::ctrl_c()).await });
+
+    (addr, handle)
+}