Implemented Message trait

Author: Relrin

src/bastion/examples/ping/src/main.rs

@@ -39,12 +39,12 @@ impl Actor for Ping {
 
         while (pong_struct.counter != 3) {
             let message = ctx.recv().await?;
+            message.handle(ctx).await;
 
-            // Do something with the message ...
-
-            message.ack().await;
             self.send(message.path(), "pong", MessageType::Tell).await?;
             pong_struct.counter += 1;
+
+            message.ack().await;
         }
 
         System::stop();

src/bastion/src/actor/context.rs

@@ -1,10 +1,11 @@
 use std::sync::Arc;
 
-use async_channel::unbounded;
+use async_channel::{unbounded, Sender};
 
 use crate::actor::local_state::LocalState;
 use crate::actor::state::ActorState;
-use crate::mailbox::traits::TypedMessage;
+use crate::mailbox::envelope::Envelope;
+use crate::mailbox::message::Message;
 use crate::mailbox::Mailbox;
 use crate::routing::path::ActorPath;
 
@@ -19,28 +20,28 @@ pub struct Context {
     /// Path to the actor in the system
     path: Arc<ActorPath>,
     /// Mailbox of the actor
-    //mailbox: Mailbox<TypedMessage>,
+    mailbox: Mailbox<Box<dyn Message>>,
     /// Local storage for actor's data
     local_state: LocalState,
     /// Current execution state of the actor
     internal_state: ActorState,
 }
 
 impl Context {
-    // FIXME: Pass the correct system_rx instead of the fake one
-    pub(crate) fn new(path: ActorPath) -> Self {
-        //let (_system_tx, system_rx) = unbounded();
-        // let mailbox = Mailbox::new(system_rx);
+    pub(crate) fn new(path: ActorPath) -> (Self, Sender<Envelope<impl Message>>) {
+        let (system_tx, system_rx) = unbounded();
 
         let path = Arc::new(path);
+        let mailbox = Mailbox::new(system_rx);
         let local_state = LocalState::new();
         let internal_state = ActorState::new();
 
-        Context {
+        let instance = Context {
             path,
-            //mailbox,
+            mailbox,
             local_state,
             internal_state,
-        }
+        };
+        (instance, system_tx)
     }
 }

src/bastion/src/mailbox/envelope.rs

@@ -1,32 +1,34 @@
+use std::cell::RefCell;
 use std::fmt::{self, Debug, Formatter};
 
 use crate::actor::actor_ref::ActorRef;
-use crate::mailbox::message::MessageType;
-use crate::mailbox::traits::TypedMessage;
+use crate::mailbox::message::{Message, MessageType};
 
 /// Struct that represents an incoming message in the actor's mailbox.
 #[derive(Clone)]
 pub struct Envelope<T>
 where
-    T: TypedMessage,
+    T: Message,
 {
     /// The sending side of a channel. In actor's world
     /// represented is a message sender. Can be used
     /// for acking message when it possible.
     sender: Option<ActorRef>,
     /// An actual data sent by the channel
-    message: T,
+    message: RefCell<Option<T>>,
     /// Message type that helps to figure out how to deliver message
     /// and how to ack it after the processing.
     message_type: MessageType,
 }
 
 impl<T> Envelope<T>
 where
-    T: TypedMessage,
+    T: Message,
 {
     /// Create a message with the given sender and inner data.
-    pub fn new(sender: Option<ActorRef>, message: T, message_type: MessageType) -> Self {
+    pub fn new(sender: Option<ActorRef>, data: T, message_type: MessageType) -> Self {
+        let message = RefCell::new(Some(data));
+
         Envelope {
             sender,
             message,
@@ -40,10 +42,17 @@ where
         self.message_type.clone()
     }
 
+    /// Extracts the message data and returns it to the caller. Each further
+    /// method call will return `None`.
+    pub fn read(&self) -> Option<T> {
+        self.message.replace(None)
+    }
+
+    // TODO: Return a boolean flag once operation has finished?
     /// Sends a confirmation to the message sender.
-    pub(crate) async fn ack(&self) {
+    pub async fn ack(&self) {
         match self.message_type {
-            MessageType::Ack => unimplemented!(),
+            MessageType::Ask => unimplemented!(),
             MessageType::Broadcast => unimplemented!(),
             MessageType::Tell => unimplemented!(),
         }
@@ -52,7 +61,7 @@ where
 
 impl<T> Debug for Envelope<T>
 where
-    T: TypedMessage,
+    T: Message,
 {
     fn fmt(&self, fmt: &mut Formatter) -> fmt::Result {
         fmt.debug_struct("Message")
@@ -61,3 +70,54 @@ where
             .finish()
     }
 }
+
+#[cfg(test)]
+mod message_target_tests {
+    use crate::mailbox::envelope::Envelope;
+    use crate::mailbox::message::{Message, MessageType};
+
+    #[derive(Debug)]
+    struct FakeMessage;
+
+    impl FakeMessage {
+        pub fn new() -> Self {
+            return FakeMessage {};
+        }
+    }
+
+    #[test]
+    fn test_message_read() {
+        let message_data = FakeMessage::new();
+        let instance = Envelope::new(None, message_data, MessageType::Tell);
+
+        let expected_data = instance.read();
+        assert_eq!(expected_data.is_some(), true);
+
+        let another_read_attempt_data = instance.read();
+        assert_eq!(another_read_attempt_data.is_none(), true);
+    }
+
+    #[test]
+    fn test_match_against_ask_message_type() {
+        let message_data = FakeMessage::new();
+        let instance = Envelope::new(None, message_data, MessageType::Ask);
+
+        assert_eq!(instance.message_type, MessageType::Ask);
+    }
+
+    #[test]
+    fn test_match_against_broadcast_message_type() {
+        let message_data = FakeMessage::new();
+        let instance = Envelope::new(None, message_data, MessageType::Broadcast);
+
+        assert_eq!(instance.message_type, MessageType::Broadcast);
+    }
+
+    #[test]
+    fn test_match_against_tell_message_type() {
+        let message_data = FakeMessage::new();
+        let instance = Envelope::new(None, message_data, MessageType::Tell);
+
+        assert_eq!(instance.message_type, MessageType::Tell);
+    }
+}

src/bastion/src/mailbox/message.rs

@@ -1,10 +1,22 @@
+use std::fmt::Debug;
+
+/// A trait that message needs to implement for typed actors (it
+/// forces message to implement the following traits: [`Any`],
+/// [`Send`] and [`Debug`]).
+///
+/// [`Any`]: https://doc.rust-lang.org/std/any/trait.Any.html
+/// [`Send`]: https://doc.rust-lang.org/std/marker/trait.Send.html
+/// [`Debug`]: https://doc.rust-lang.org/std/fmt/trait.Debug.html
+pub trait Message: Send + Debug + 'static {}
+impl<T> Message for T where T: ?Sized + Send + Debug + 'static {}
+
 /// Enum that provides information what type of the message
 /// being sent through the channel.
 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
 pub enum MessageType {
     /// A message type that requires sending a confirmation to the
     /// sender after begin the processing stage.
-    Ack,
+    Ask,
     /// A message that can be broadcasted (e.g. via system dispatchers). This
     /// message type doesn't require to be acked from the receiver's side.
     Broadcast,

src/bastion/src/mailbox/mod.rs

@@ -1,8 +1,6 @@
-mod envelope;
-mod state;
-
+pub mod envelope;
 pub mod message;
-pub mod traits;
+pub(crate) mod state;
 
 use std::sync::atomic::AtomicBool;
 use std::sync::Arc;
@@ -11,14 +9,14 @@ use async_channel::{unbounded, Receiver, Sender};
 
 use crate::error::{BastionError, Result};
 use crate::mailbox::envelope::Envelope;
+use crate::mailbox::message::Message;
 use crate::mailbox::state::MailboxState;
-use crate::mailbox::traits::TypedMessage;
 
 /// Struct that represents a message sender.
 #[derive(Clone)]
 pub struct MailboxTx<T>
 where
-    T: TypedMessage,
+    T: Message,
 {
     /// Indicated the transmitter part of the actor's channel
     /// which is using for passing messages.
@@ -30,7 +28,7 @@ where
 
 impl<T> MailboxTx<T>
 where
-    T: TypedMessage,
+    T: Message,
 {
     /// Return a new instance of MailboxTx that indicates sender.
     pub(crate) fn new(tx: Sender<Envelope<T>>) -> Self {
@@ -57,110 +55,66 @@ where
 #[derive(Clone)]
 pub struct Mailbox<T>
 where
-    T: TypedMessage,
+    T: Message,
 {
-    /// User guardian sender
-    user_tx: MailboxTx<T>,
-    /// User guardian receiver
-    user_rx: Receiver<Envelope<T>>,
+    /// Actor guardian sender
+    actor_tx: MailboxTx<T>,
+    /// Actor guardian receiver
+    actor_rx: Receiver<Envelope<T>>,
     /// System guardian receiver
     system_rx: Receiver<Envelope<T>>,
-    /// The current processing message, received from the
-    /// latest call to the user's queue
-    last_user_message: Option<Envelope<T>>,
-    /// The current processing message, received from the
-    /// latest call to the system's queue
-    last_system_message: Option<Envelope<T>>,
     /// Mailbox state machine
     state: Arc<MailboxState>,
 }
 
 // TODO: Add calls with recv with timeout
 impl<T> Mailbox<T>
 where
-    T: TypedMessage,
+    T: Message,
 {
     /// Creates a new mailbox for the actor.
     pub(crate) fn new(system_rx: Receiver<Envelope<T>>) -> Self {
-        let (tx, user_rx) = unbounded();
-        let user_tx = MailboxTx::new(tx);
-        let last_user_message = None;
-        let last_system_message = None;
+        let (tx, actor_rx) = unbounded();
+        let actor_tx = MailboxTx::new(tx);
         let state = Arc::new(MailboxState::new());
 
         Mailbox {
-            user_tx,
-            user_rx,
+            actor_tx,
+            actor_rx,
             system_rx,
-            last_user_message,
-            last_system_message,
             state,
         }
     }
 
-    /// Forced receive message from user queue
+    /// Forced receive message from the actor's queue.
     pub async fn recv(&mut self) -> Envelope<T> {
-        let message = self
-            .user_rx
+        self.actor_rx
             .recv()
             .await
             .map_err(|e| BastionError::ChanRecv(e.to_string()))
-            .unwrap();
-
-        self.last_user_message = Some(message);
-        self.last_user_message.clone().unwrap()
+            .unwrap()
     }
 
-    /// Try receiving message from user queue
+    /// Try receiving message from the actor's queue.
     pub async fn try_recv(&mut self) -> Result<Envelope<T>> {
-        if self.last_user_message.is_some() {
-            return Err(BastionError::UnackedMessage);
-        }
-
-        match self.user_rx.try_recv() {
-            Ok(message) => {
-                self.last_user_message = Some(message);
-                Ok(self.last_user_message.clone().unwrap())
-            }
-            Err(e) => Err(BastionError::ChanRecv(e.to_string())),
-        }
+        self.actor_rx
+            .try_recv()
+            .map_err(|e| BastionError::ChanRecv(e.to_string()))
     }
 
-    /// Forced receive message from system queue
+    /// Forced receive message from the internal system queue.
     pub async fn sys_recv(&mut self) -> Envelope<T> {
-        let message = self
-            .system_rx
+        self.system_rx
             .recv()
             .await
             .map_err(|e| BastionError::ChanRecv(e.to_string()))
-            .unwrap();
-
-        self.last_system_message = Some(message);
-        self.last_system_message.clone().unwrap()
+            .unwrap()
     }
 
-    /// Try receiving message from system queue
+    /// Try receiving message from the internal system queue.
     pub async fn try_sys_recv(&mut self) -> Result<Envelope<T>> {
-        if self.last_system_message.is_some() {
-            return Err(BastionError::UnackedMessage);
-        }
-
-        match self.system_rx.try_recv() {
-            Ok(message) => {
-                self.last_system_message = Some(message);
-                Ok(self.last_system_message.clone().unwrap())
-            }
-            Err(e) => Err(BastionError::ChanRecv(e.to_string())),
-        }
-    }
-
-    /// Returns the last retrieved message from the user channel
-    pub async fn get_last_user_message(&self) -> Option<Envelope<T>> {
-        self.last_user_message.clone()
-    }
-
-    /// Returns the last retrieved message from the system channel
-    pub async fn get_last_system_message(&self) -> Option<Envelope<T>> {
-        self.last_system_message.clone()
+        self.system_rx
+            .try_recv()
+            .map_err(|e| BastionError::ChanRecv(e.to_string()))
     }
 }