🐛(backend) LRSHTTP methods return an error when run inside an asynchroneous function.

[Leobouloc]

Bug Report

Expected behavior/code
LRSHTTP.status() and all other methods should work when called inside an async function.

Actual Behavior
As reported openfun/warren#44 (comment) , the LRSHTTP methods returns an error when called within an events loop. The problem is caused by nesting of asyncio.get_event_loop().run_until_complete(...), which is not allowed.

Steps to Reproduce
Add and run test:

import asyncio
from unittest.mock import AsyncMock

import pytest

from ralph.backends.http.async_lrs import AsyncLRSHTTP, HTTPBackendStatus
from ralph.backends.http.lrs import LRSHTTP

@pytest.mark.anyio
async def test_backend_http_lrs_in_async_setting(monkeypatch):
    """Test that backend works when run in async function."""

    async def async_function():
        lrs = LRSHTTP()
        status_mock_response = HTTPBackendStatus.OK
        status_mock = AsyncMock(return_value=status_mock_response)
        monkeypatch.setattr(AsyncLRSHTTP, "status", status_mock)
        assert lrs.status() == status_mock_response
    
    await async_function()

Results in:

=================================================================== FAILURES ===================================================================
____________________________________________________ test_backend_http_lrs_in_async_setting ____________________________________________________

monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f2a4181dfd0>

    @pytest.mark.anyio
    async def test_backend_http_lrs_in_async_setting(monkeypatch):
        """Test that backend works when run in async function."""
    
        async def async_function():
            lrs = LRSHTTP()
            status_mock_response = HTTPBackendStatus.OK
            status_mock = AsyncMock(return_value=status_mock_response)
            monkeypatch.setattr(AsyncLRSHTTP, "status", status_mock)
            assert lrs.status() == status_mock_response
    
>       await async_function()

tests/backends/http/test_lrs.py:27: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
tests/backends/http/test_lrs.py:25: in async_function
    assert lrs.status() == status_mock_response
src/ralph/backends/http/lrs.py:19: in status
    return asyncio.get_event_loop().run_until_complete(
/usr/local/lib/python3.11/asyncio/base_events.py:629: in run_until_complete
    self._check_running()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <_UnixSelectorEventLoop running=False closed=True debug=False>

    def _check_running(self):
        if self.is_running():
>           raise RuntimeError('This event loop is already running')
E           RuntimeError: This event loop is already running

/usr/local/lib/python3.11/asyncio/base_events.py:588: RuntimeError


FAILED tests/backends/http/test_lrs.py::test_backend_http_lrs_in_async_setting - RuntimeError: This event loop is already running

Environment

• Ralph version: 3.9

Possible Solution
The first answer of this post suggest to use nest-asyncio.