Added the initial session service.

src/session.rs

@@ -0,0 +1,89 @@
+use crate::queue::{Message, MsgType, Queue};
+use std::{
+    sync::mpsc::{channel, Receiver},
+    thread::spawn,
+};
+use uuid::Uuid;
+
+const RESPONS_TO: [MsgType; 1] = [MsgType::SessionValidate];
+
+struct Session {
+    queue: Queue,
+    rx: Receiver<Message>,
+}
+
+impl Session {
+    fn new(queue: Queue, rx: Receiver<Message>) -> Self {
+        Self {
+            queue: queue,
+            rx: rx,
+        }
+    }
+
+    fn start(queue: Queue) {
+        let (tx, rx) = channel();
+        let session = Session::new(queue, rx);
+        session.queue.add(tx, RESPONS_TO.to_vec());
+        spawn(move || {
+            session.listen();
+        });
+    }
+
+    fn listen(&self) {
+        loop {
+            let msg = self.rx.recv().unwrap();
+            self.validate(msg);
+        }
+    }
+
+    fn validate(&self, msg: Message) {
+        let mut reply = msg.reply(MsgType::Session);
+        reply.add_data("sess_id", Uuid::new_v4());
+        self.queue.send(reply);
+    }
+}
+
+#[cfg(test)]
+mod sessions {
+    use super::*;
+    use crate::queue::{Message, MsgType};
+    use std::{sync::mpsc::channel, time::Duration};
+
+    static TIMEOUT: Duration = Duration::from_millis(500);
+
+    #[test]
+    fn get_new_session() {
+        let queue = Queue::new();
+        let (tx, rx) = channel();
+        queue.add(tx, [MsgType::Session].to_vec());
+        Session::start(queue.clone());
+        let msg = Message::new(MsgType::SessionValidate);
+        queue.send(msg.clone());
+        let result = rx.recv_timeout(TIMEOUT).unwrap();
+        match result.get_class() {
+            MsgType::Session => {}
+            _ => unreachable!(
+                "received {:?}, should have been a session",
+                result.get_class()
+            ),
+        }
+        assert_eq!(result.get_id(), msg.get_id());
+    }
+
+    #[test]
+    fn session_id_is_unique() {
+        let queue = Queue::new();
+        let (tx, rx) = channel();
+        queue.add(tx, [MsgType::Session].to_vec());
+        Session::start(queue.clone());
+        let msg = Message::new(MsgType::SessionValidate);
+        let mut ids: Vec<Uuid> = Vec::new();
+        for _ in 0..10 {
+            queue.send(msg.clone());
+            let result = rx.recv().unwrap();
+            let id = result.get_data().get("sess_id").unwrap().to_uuid().unwrap();
+            assert!(!ids.contains(&id), "{} is a duplicate id", id);
+            ids.push(id);
+        }
+    }
+}