Implement unsubscription TODOs [skip ci]

crates/starknet-devnet-server/src/api/json_rpc/endpoints_ws.rs

@@ -30,7 +30,7 @@ impl JsonRpcHandler {
                     }),
                 )?;
 
-                socket_context.unsubscribe(subscription_id).await;
+                socket_context.unsubscribe(rpc_request_id, subscription_id).await;
                 Ok(())
             }
         }

crates/starknet-devnet-server/src/api/json_rpc/mod.rs

@@ -1423,8 +1423,8 @@ mod response_tests {
     use crate::api::json_rpc::ToRpcResponseResult;
 
     #[test]
-    fn serializing_starknet_response_empty_variant_has_to_produce_empty_json_object_when_converted_to_rpc_result(
-    ) {
+    fn serializing_starknet_response_empty_variant_has_to_produce_empty_json_object_when_converted_to_rpc_result()
+     {
         assert_eq!(
             r#"{"result":{}}"#,
             serde_json::to_string(

crates/starknet-devnet-server/src/subscribe.rs

@@ -1,4 +1,5 @@
-use std::{collections::HashMap, sync::Arc};
+use std::collections::HashMap;
+use std::sync::Arc;
 
 use axum::extract::ws::{Message, WebSocket};
 use futures::stream::SplitSink;
@@ -7,6 +8,7 @@ use serde::{self, Serialize};
 use starknet_types::rpc::block::BlockHeader;
 use tokio::sync::Mutex;
 
+use crate::rpc_core::error::{ErrorCode, RpcError};
 use crate::rpc_core::request::Id;
 
 pub type SocketId = u64;
@@ -59,6 +61,7 @@ impl SubscriptionNotification {
 pub enum SubscriptionResponse {
     Confirmation { rpc_request_id: Id, result: SubscriptionConfirmation },
     Notification { subscription_id: SubscriptionId, data: SubscriptionNotification },
+    Invalid(RpcError),
 }
 
 impl SubscriptionResponse {
@@ -79,11 +82,20 @@ impl SubscriptionResponse {
                     }
                 })
             }
+            SubscriptionResponse::Invalid(rpc_error) => serde_json::json!(rpc_error),
         };
 
         resp["jsonrpc"] = "2.0".into();
         resp
     }
+
+    fn invalid_subscription_id() -> Self {
+        Self::Invalid(RpcError {
+            code: ErrorCode::ServerError(66),
+            message: "Invalid subscription id".into(),
+            data: None,
+        })
+    }
 }
 
 pub struct SocketContext {
@@ -118,11 +130,15 @@ impl SocketContext {
         subscription_id
     }
 
-    pub async fn unsubscribe(&mut self, subscription_id: SubscriptionId) {
-        match self.subscriptions.remove(&subscription_id) {
-            Some(_) => todo!("return true"),
-            None => todo!("return INVALID_SUBSCRIPTION_ID"),
-        }
+    pub async fn unsubscribe(&mut self, rpc_request_id: Id, subscription_id: SubscriptionId) {
+        let resp = match self.subscriptions.remove(&subscription_id) {
+            Some(_) => SubscriptionResponse::Confirmation {
+                rpc_request_id,
+                result: SubscriptionConfirmation::UnsubscriptionConfirmation(true),
+            },
+            None => SubscriptionResponse::invalid_subscription_id(),
+        };
+        self.send(resp).await;
     }
 
     pub async fn notify(&self, subscription_id: SubscriptionId, data: SubscriptionNotification) {
@@ -137,7 +153,7 @@ impl SocketContext {
                         self.notify(*subscription_id, data.clone()).await;
                     }
                 }
-                other => println!("DEBUG unsupported subscription: {other:?}"),
+                other => panic!("DEBUG unsupported subscription: {other:?}"),
             }
         }
     }