feat: with subscription

Signed-off-by: kjuulh <contact@kjuulh.io>

crates/crunch-traits/Cargo.toml

@@ -11,3 +11,4 @@ tokio.workspace = true
 thiserror.workspace = true
 async-trait.workspace = true
 uuid.workspace = true
+futures.workspace = true

crates/crunch-traits/src/errors.rs

@@ -27,6 +27,18 @@ pub enum PublishError {
     ConnectionError(#[source] anyhow::Error),
 }
 
+#[derive(Error, Debug)]
+pub enum SubscriptionError {
+    #[error("failed to subscribe: {0}")]
+    FailedToSubscribe(#[source] anyhow::Error),
+
+    #[error("connection failed: {0}")]
+    ConnectionFailed(#[source] TransportError),
+
+    #[error("failed to deserialize{0}")]
+    DeserializationFailed(#[source] DeserializeError),
+}
+
 #[derive(Error, Debug)]
 pub enum TransportError {
     #[error("to publish to transport {0}")]

crates/crunch-traits/src/lib.rs

@@ -38,7 +38,11 @@ impl Display for EventInfo {
 }
 
 pub trait Event: Serializer + Deserializer {
-    fn event_info(&self) -> EventInfo;
+    fn event_info() -> EventInfo;
+
+    fn int_event_info(&self) -> EventInfo {
+        Self::event_info()
+    }
 }
 
 pub mod errors;

crates/crunch-traits/src/transport.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use std::{pin::Pin, sync::Arc};
 
 use async_trait::async_trait;
 
@@ -6,7 +6,19 @@ use crate::{errors::TransportError, EventInfo};
 
 #[async_trait]
 pub trait Transport {
+    type Stream: futures::Stream<Item = Vec<u8>>;
+
     async fn publish(&self, event_info: &EventInfo, content: Vec<u8>)
         -> Result<(), TransportError>;
+    async fn subscriber(
+        &self,
+        event_info: &EventInfo,
+    ) -> Result<Option<Self::Stream>, TransportError>;
 }
-pub type DynTransport = Arc<dyn Transport + Send + Sync + 'static>;
+
+pub type DynTransport = Arc<
+    dyn Transport<Stream = Pin<Box<dyn futures::Stream<Item = Vec<u8>> + Send>>>
+        + Send
+        + Sync
+        + 'static,
+>;