feat: Run exec_request inside a task

CHANGELOG.md

@@ -29,15 +29,15 @@
 - Fix expected text depending on IPython version. [#1354](https://github.com/ipython/ipykernel/pull/1354) ([@Carreau](https://github.com/Carreau))
 - Another try at tracking down ResourceWarning with tracemalloc. [#1353](https://github.com/ipython/ipykernel/pull/1353) ([@Carreau](https://github.com/Carreau))
 - Remove deprecated modules since 4.3 (2016). [#1352](https://github.com/ipython/ipykernel/pull/1352) ([@Carreau](https://github.com/Carreau))
-- Try to reenable tests from downstream ipywidgets [#1350](https://github.com/ipython/ipykernel/pull/1350) ([@Carreau](https://github.com/Carreau))
+- Try to re-enable tests from downstream ipywidgets [#1350](https://github.com/ipython/ipykernel/pull/1350) ([@Carreau](https://github.com/Carreau))
 - Disable 3 failing downstream tests, but keep testing the rest. [#1349](https://github.com/ipython/ipykernel/pull/1349) ([@Carreau](https://github.com/Carreau))
-- Licence :: * trove classifers are deprecated [#1348](https://github.com/ipython/ipykernel/pull/1348) ([@Carreau](https://github.com/Carreau))
+- Licence :: * trove classifiers are deprecated [#1348](https://github.com/ipython/ipykernel/pull/1348) ([@Carreau](https://github.com/Carreau))
 - Pin sphinx to resolve docs build failures [#1347](https://github.com/ipython/ipykernel/pull/1347) ([@krassowski](https://github.com/krassowski))
 - Make our own mock kernel methods async [#1346](https://github.com/ipython/ipykernel/pull/1346) ([@Carreau](https://github.com/Carreau))
 - Try to debug non-closed iopub socket [#1345](https://github.com/ipython/ipykernel/pull/1345) ([@Carreau](https://github.com/Carreau))
 - Email is @python.org since 2018 [#1343](https://github.com/ipython/ipykernel/pull/1343) ([@Carreau](https://github.com/Carreau))
 - Remove unused ignores lints. [#1342](https://github.com/ipython/ipykernel/pull/1342) ([@Carreau](https://github.com/Carreau))
-- Enable ruff G002 and fix 6 occurences [#1341](https://github.com/ipython/ipykernel/pull/1341) ([@Carreau](https://github.com/Carreau))
+- Enable ruff G002 and fix 6 occurrences [#1341](https://github.com/ipython/ipykernel/pull/1341) ([@Carreau](https://github.com/Carreau))
 - Check ignores warnings are still relevant. [#1340](https://github.com/ipython/ipykernel/pull/1340) ([@Carreau](https://github.com/Carreau))
 - Move mypy disablinging error codes on a per-file basis [#1338](https://github.com/ipython/ipykernel/pull/1338) ([@Carreau](https://github.com/Carreau))
 - try to fix spyder kernel install [#1337](https://github.com/ipython/ipykernel/pull/1337) ([@Carreau](https://github.com/Carreau))
@@ -46,7 +46,7 @@
 - Bump mypy [#1333](https://github.com/ipython/ipykernel/pull/1333) ([@Carreau](https://github.com/Carreau))
 - Remove dead code. [#1332](https://github.com/ipython/ipykernel/pull/1332) ([@Carreau](https://github.com/Carreau))
 - Ignore or fix most of the remaining ruff 0.9.6 errors [#1331](https://github.com/ipython/ipykernel/pull/1331) ([@Carreau](https://github.com/Carreau))
-- minor code reformating valid ruff 0.9.6 [#1330](https://github.com/ipython/ipykernel/pull/1330) ([@Carreau](https://github.com/Carreau))
+- minor code reformatting valid ruff 0.9.6 [#1330](https://github.com/ipython/ipykernel/pull/1330) ([@Carreau](https://github.com/Carreau))
 - Some formatting changes to prepare bumping ruff pre-commit. [#1329](https://github.com/ipython/ipykernel/pull/1329) ([@Carreau](https://github.com/Carreau))
 - Manually update Codespell and fix new errors. [#1328](https://github.com/ipython/ipykernel/pull/1328) ([@Carreau](https://github.com/Carreau))
 - Manually update mdformat pre-commit and run it. [#1327](https://github.com/ipython/ipykernel/pull/1327) ([@Carreau](https://github.com/Carreau))

ipykernel/comm/comm.py

@@ -39,7 +39,7 @@ def publish_msg(self, msg_type, data=None, metadata=None, buffers=None, **keys):
             msg_type,
             content,
             metadata=json_clean(metadata),
-            parent=self.kernel.get_parent(),
+            parent=self.kernel.parent_msg,
             ident=self.topic,
             buffers=buffers,
         )

ipykernel/eventloops.py

@@ -6,7 +6,6 @@
 import os
 import platform
 import sys
-from functools import partial
 
 import zmq
 from packaging.version import Version as V
@@ -400,63 +399,11 @@ def loop_cocoa_exit(kernel):
 
 @register_integration("asyncio")
 def loop_asyncio(kernel):
-    """Start a kernel with asyncio event loop support."""
-    import asyncio
-
-    loop = asyncio.get_event_loop()
-    # loop is already running (e.g. tornado 5), nothing left to do
-    if loop.is_running():
-        return
-
-    if loop.is_closed():
-        # main loop is closed, create a new one
-        loop = asyncio.new_event_loop()
-        asyncio.set_event_loop(loop)
-    loop._should_close = False  # type:ignore[attr-defined]
+    """Verify the asyncio event loop is supported."""
 
-    # pause eventloop when there's an event on a zmq socket
-    def process_stream_events(socket):
-        """fall back to main loop when there's a socket event"""
-        loop.stop()
-
-    notifier = partial(process_stream_events, kernel.shell_socket)
-    loop.add_reader(kernel.shell_socket.getsockopt(zmq.FD), notifier)
-    loop.call_soon(notifier)
-
-    while True:
-        error = None
-        try:
-            loop.run_forever()
-        except KeyboardInterrupt:
-            continue
-        except Exception as e:
-            error = e
-        if loop._should_close:  # type:ignore[attr-defined]
-            loop.close()
-        if error is not None:
-            raise error
-        break
-
-
-@loop_asyncio.exit
-def loop_asyncio_exit(kernel):
-    """Exit hook for asyncio"""
     import asyncio
 
-    loop = asyncio.get_event_loop()
-
-    async def close_loop():
-        if hasattr(loop, "shutdown_asyncgens"):
-            yield loop.shutdown_asyncgens()
-        loop._should_close = True  # type:ignore[attr-defined]
-        loop.stop()
-
-    if loop.is_running():
-        close_loop()
-
-    elif not loop.is_closed():
-        loop.run_until_complete(close_loop)  # type:ignore[arg-type]
-        loop.close()
+    asyncio.get_running_loop()
 
 
 def set_qt_api_env_from_gui(gui):
@@ -602,13 +549,3 @@ def enable_gui(gui, kernel=None):
         msg = "Cannot activate multiple GUI eventloops"  # type:ignore[unreachable]
         raise RuntimeError(msg)
     kernel.eventloop = loop
-    # We set `eventloop`; the function the user chose is executed in `Kernel.enter_eventloop`, thus
-    # any exceptions raised during the event loop will not be shown in the client.
-
-    # If running in async loop then set anyio event to trigger starting the eventloop.
-    # If not running in async loop do nothing as this will be handled in IPKernelApp.main().
-    try:
-        kernel._eventloop_set.set()
-    except RuntimeError:
-        # Expecting sniffio.AsyncLibraryNotFoundError but don't want to import sniffio just for that
-        pass

ipykernel/inprocess/ipkernel.py

@@ -95,7 +95,7 @@ def stop(self):
     def _abort_queues(self):
         """The in-process kernel doesn't abort requests."""
 
-    def _input_request(self, prompt, ident, parent, password=False):
+    def _input_request(self, prompt, *, password=False):
         # Flush output before making the request.
         self.raw_input_str = None
         if sys.stdout is not None:
@@ -106,10 +106,10 @@ def _input_request(self, prompt, ident, parent, password=False):
         # Send the input request.
         content = json_clean(dict(prompt=prompt, password=password))
         assert self.session is not None
-        msg = self.session.msg("input_request", content, parent)
+        msg = self.session.msg("input_request", content, self.parent_msg)
         for frontend in self.frontends:
             assert frontend is not None
-            if frontend.session.session == parent["header"]["session"]:
+            if frontend.session.session == self.parent_msg["header"]["session"]:
                 frontend.stdin_channel.call_handlers(msg)
                 break
         else:

ipykernel/ipkernel.py

@@ -286,43 +286,11 @@ def stop(self):
         if self.debugpy_socket is not None:
             self.debugpy_stop.set()
 
-    def set_parent(self, ident, parent, channel="shell"):
-        """Overridden from parent to tell the display hook and output streams
-        about the parent message.
-        """
-        super().set_parent(ident, parent, channel)
-        if channel == "shell" and self.shell:
+    def _set_parent_ident(self, parent, ident):
+        super()._set_parent_ident(parent, ident)
+        if self.shell:
             self.shell.set_parent(parent)
 
-    def init_metadata(self, parent):
-        """Initialize metadata.
-
-        Run at the beginning of each execution request.
-        """
-        md = super().init_metadata(parent)
-        # FIXME: remove deprecated ipyparallel-specific code
-        # This is required for ipyparallel < 5.0
-        md.update(
-            {
-                "dependencies_met": True,
-                "engine": self.ident,
-            }
-        )
-        return md
-
-    def finish_metadata(self, parent, metadata, reply_content):
-        """Finish populating metadata.
-
-        Run after completing an execution request.
-        """
-        # FIXME: remove deprecated ipyparallel-specific code
-        # This is required by ipyparallel < 5.0
-        metadata["status"] = reply_content["status"]
-        if reply_content["status"] == "error" and reply_content["ename"] == "UnmetDependency":
-            metadata["dependencies_met"] = False
-
-        return metadata
-
     def _forward_input(self, allow_stdin=False):
         """Forward raw_input and getpass to the current frontend.
 
@@ -478,10 +446,6 @@ async def run(execution: Execution) -> None:
                 }
             )
 
-            # FIXME: deprecated piece for ipyparallel (remove in 5.0):
-            e_info = dict(engine_uuid=self.ident, engine_id=self.int_id, method="execute")
-            reply_content["engine_info"] = e_info
-
         # Return the execution counter so clients can display prompts
         reply_content["execution_count"] = shell.execution_count - 1
 
@@ -662,72 +626,6 @@ def do_is_complete(self, code):
             r["indent"] = " " * indent_spaces
         return r
 
-    def do_apply(self, content, bufs, msg_id, reply_metadata):
-        """Handle an apply request."""
-        try:
-            from ipyparallel.serialize import serialize_object, unpack_apply_message
-        except ImportError:
-            from .serialize import serialize_object, unpack_apply_message
-
-        shell = self.shell
-        assert shell is not None
-        try:
-            working = shell.user_ns
-
-            prefix = "_" + str(msg_id).replace("-", "") + "_"
-            f, args, kwargs = unpack_apply_message(bufs, working, copy=False)
-
-            fname = getattr(f, "__name__", "f")
-
-            fname = prefix + "f"
-            argname = prefix + "args"
-            kwargname = prefix + "kwargs"
-            resultname = prefix + "result"
-
-            ns = {fname: f, argname: args, kwargname: kwargs, resultname: None}
-            # print ns
-            working.update(ns)
-            code = f"{resultname} = {fname}(*{argname},**{kwargname})"
-            try:
-                exec(code, shell.user_global_ns, shell.user_ns)
-                result = working.get(resultname)
-            finally:
-                for key in ns:
-                    working.pop(key)
-
-            assert self.session is not None
-            result_buf = serialize_object(
-                result,
-                buffer_threshold=self.session.buffer_threshold,
-                item_threshold=self.session.item_threshold,
-            )
-
-        except BaseException as e:
-            # invoke IPython traceback formatting
-            shell.showtraceback()
-            reply_content = {
-                "traceback": shell._last_traceback or [],
-                "ename": str(type(e).__name__),
-                "evalue": str(e),
-            }
-            # FIXME: deprecated piece for ipyparallel (remove in 5.0):
-            e_info = dict(engine_uuid=self.ident, engine_id=self.int_id, method="apply")
-            reply_content["engine_info"] = e_info
-
-            self.send_response(
-                self.iopub_socket,
-                "error",
-                reply_content,
-                ident=self._topic("error"),
-            )
-            self.log.info("Exception in apply request:\n%s", "\n".join(reply_content["traceback"]))
-            result_buf = []
-            reply_content["status"] = "error"
-        else:
-            reply_content = {"status": "ok"}
-
-        return reply_content, result_buf
-
     def do_clear(self):
         """Clear the kernel."""
         if self.shell:

ipykernel/kernelapp.py

@@ -20,7 +20,7 @@
 
 import zmq
 import zmq_anyio
-from anyio import create_task_group, run, to_thread
+from anyio import create_task_group, run
 from IPython.core.application import (  # type:ignore[attr-defined]
     BaseIPythonApplication,
     base_aliases,
@@ -764,18 +764,10 @@ def start(self) -> None:
         backend = "trio" if self.trio_loop else "asyncio"
         run(partial(self._start, backend), backend=backend)
 
-    async def _wait_to_enter_eventloop(self) -> None:
-        await to_thread.run_sync(self.kernel._eventloop_set.wait)
-        await self.kernel.enter_eventloop()
-
     async def main(self) -> None:
         async with create_task_group() as tg:
-            tg.start_soon(self._wait_to_enter_eventloop)
             tg.start_soon(self.kernel.start)
 
-        if self.kernel.eventloop:
-            self.kernel._eventloop_set.set()
-
     def stop(self) -> None:
         """Stop the kernel, thread-safe."""
         self.kernel.stop()