commiting missing files

core/src/subscription_sink.rs

@@ -0,0 +1,8 @@
+use async_trait::async_trait;
+use solana_sdk::slot_history::Slot;
+
+#[async_trait]
+pub trait SubscriptionSink {
+    async fn send(&self, slot: Slot, message: serde_json::Value);
+    fn is_closed(&self) -> bool;
+}

lite-rpc/src/jsonrpsee_subscrption_handler_sink.rs

@@ -0,0 +1,41 @@
+use async_trait::async_trait;
+use jsonrpsee::{SubscriptionSink, SubscriptionMessage};
+use solana_rpc_client_api::response::{RpcResponseContext, Response as RpcResponse};
+
+pub struct JsonRpseeSubscriptionHandlerSink {
+    jsonrpsee_sink : SubscriptionSink,
+}
+
+impl JsonRpseeSubscriptionHandlerSink {
+    pub fn new(jsonrpsee_sink : SubscriptionSink) -> Self {
+        Self { jsonrpsee_sink }
+    } 
+}
+
+#[async_trait]
+impl solana_lite_rpc_core::subscription_sink::SubscriptionSink for JsonRpseeSubscriptionHandlerSink {
+    async fn send(&self, slot: solana_sdk::slot_history::Slot, message: serde_json::Value) {
+        let _ = self.jsonrpsee_sink.send(
+                SubscriptionMessage::from_json(&RpcResponse {
+                    context: RpcResponseContext {
+                        slot,
+                        api_version: None,
+                    },
+                    value: message,
+                })
+                .unwrap(),
+            )
+            .await;
+    }
+
+    fn is_closed(&self) -> bool {
+        self.jsonrpsee_sink.is_closed()
+    }
+}
+
+unsafe impl Send for JsonRpseeSubscriptionHandlerSink {
+}
+
+unsafe impl Sync for JsonRpseeSubscriptionHandlerSink {
+    
+}