Add place holder for membership info protocol

src/node/protocol/membership.rs

@@ -0,0 +1,110 @@
+// Copyright 2024 Kulpreet Singh
+
+// This file is part of Frost-Federation
+
+// Frost-Federation is free software: you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+
+// Frost-Federation is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Frost-Federation. If not, see
+// <https://www.gnu.org/licenses/>.
+
+use crate::node::protocol::Message;
+use futures::{Future, FutureExt};
+use serde::{Deserialize, Serialize};
+use std::pin::Pin;
+use std::task::{Context, Poll};
+use tower::{BoxError, Service};
+
+#[derive(Debug, Serialize, Deserialize, PartialEq, Clone, Default)]
+pub struct MembershipMessage {
+    pub sender_id: String,
+    pub message: Vec<String>,
+}
+
+impl MembershipMessage {
+    pub fn new(sender_id: String, members: Vec<String>) -> Self {
+        MembershipMessage {
+            sender_id,
+            message: members,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct Membership {
+    sender_id: String,
+}
+
+impl Membership {
+    pub fn new(node_id: String) -> Self {
+        Membership { sender_id: node_id }
+    }
+}
+
+/// Service for handling Membership protocol.
+impl Service<Message> for Membership {
+    type Response = Option<Message>;
+    type Error = BoxError;
+    type Future = Pin<Box<dyn Future<Output = Result<Option<Message>, Self::Error>> + Send>>;
+
+    fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+        Poll::Ready(Ok(()))
+    }
+
+    /// Membership doesn't respond with anything. It is pushed by a
+    /// node when anyone connects to it.
+    fn call(&mut self, _msg: Message) -> Self::Future {
+        async move { Ok(None) }.boxed()
+    }
+}
+
+#[cfg(test)]
+mod membership_tests {
+
+    use super::Membership;
+    use crate::node::protocol::MembershipMessage;
+    use tower::{Service, ServiceExt};
+
+    #[tokio::test]
+    async fn it_should_create_membership_as_service_and_respond_to_none_with_membership() {
+        let mut p = Membership::new("local".to_string());
+        let res = p
+            .ready()
+            .await
+            .unwrap()
+            .call(MembershipMessage::default().into())
+            .await
+            .unwrap();
+        assert!(res.is_none());
+        // assert_eq!(
+        //     res,
+        //     Some(MembershipMessage::new("local".to_string(), vec!["a".to_string()]).into())
+        // );
+    }
+
+    #[tokio::test]
+    async fn it_should_create_membership_as_service_and_respond_to_membership_with_none() {
+        let mut p = Membership::new("local".to_string());
+        let res = p
+            .ready()
+            .await
+            .unwrap()
+            .call(MembershipMessage::new("local".to_string(), vec!["a".to_string()]).into())
+            .await
+            .unwrap();
+        assert!(res.is_none());
+    }
+
+    #[test]
+    fn it_should_create_default_membership_message() {
+        assert_eq!(MembershipMessage::default().sender_id, "".to_string())
+    }
+}