deltachat-rpc-server: spawn request handlers

CHANGELOG.md

@@ -5,6 +5,8 @@
 ### Changes
 
 ### Fixes
+- deltachat-rpc-server: do not block stdin while processing the request. #4041
+  deltachat-rpc-server now reads the next request as soon as previous request handler is spawned.
 
 ### API-Changes
 - Remove `MimeMessage::from_bytes()` public interface. #4033

deltachat-jsonrpc/src/api/mod.rs

@@ -85,6 +85,11 @@ impl CommandApi {
 
 #[rpc(all_positional, ts_outdir = "typescript/generated")]
 impl CommandApi {
+    /// Test function.
+    async fn sleep(&self, delay: f64) {
+        tokio::time::sleep(std::time::Duration::from_secs_f64(delay)).await
+    }
+
     // ---------------------------------------------
     //  Misc top level functions
     // ---------------------------------------------

deltachat-rpc-client/tests/test_something.py

@@ -1,6 +1,7 @@
 from unittest.mock import MagicMock
 
 import pytest
+import asyncio
 
 from deltachat_rpc_client import EventType, events
 from deltachat_rpc_client.rpc import JsonRpcError
@@ -13,6 +14,17 @@ async def test_system_info(rpc) -> None:
     assert "deltachat_core_version" in system_info
 
 
+@pytest.mark.asyncio()
+async def test_sleep(rpc) -> None:
+    """Test that long-running task does not block short-running task from completion."""
+    sleep_5_task = asyncio.create_task(rpc.sleep(5.0))
+    sleep_3_task = asyncio.create_task(rpc.sleep(3.0))
+    done, pending = await asyncio.wait([sleep_5_task, sleep_3_task], return_when=asyncio.FIRST_COMPLETED)
+    assert sleep_3_task in done
+    assert sleep_5_task in pending
+    sleep_5_task.cancel()
+
+
 @pytest.mark.asyncio()
 async def test_email_address_validity(rpc) -> None:
     valid_addresses = [

deltachat-rpc-server/src/bin/deltachat-rpc-server/main.rs

@@ -51,7 +51,10 @@ async fn main() -> Result<()> {
         let mut lines = BufReader::new(stdin).lines();
         while let Some(message) = lines.next_line().await? {
             log::trace!("RPC recv {}", message);
-            session.handle_incoming(&message).await;
+            let session = session.clone();
+            tokio::spawn(async move {
+                session.handle_incoming(&message).await;
+            });
         }
         log::info!("EOF reached on stdin");
         Ok(())