Fix repeated activities and logging interval

.github/workflows/run_tests.yml

@@ -62,3 +62,35 @@ jobs:
           hide-comment: false
           report-only-changed-files: false
           junitxml-path: ./pytest.xml
+
+  # The pip job is pinned to Python 3.8 by pykep's wheels, but that is exactly the
+  # version where asyncio.get_event_loop() still papers over a missing loop, so the
+  # 3.10+ path would otherwise go untested. conda gets us a modern Python and
+  # doubles as a check that environment.yml still solves.
+  build-conda:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    env:
+      MPLBACKEND: Agg
+      PYTHONUNBUFFERED: "1"
+    permissions:
+      contents: read
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up conda environment from environment.yml
+        uses: conda-incubator/setup-miniconda@v3
+        with:
+          environment-file: environment.yml
+          activate-environment: paseos
+          miniforge-version: latest
+      # environment.yml only says python>=3.8, so guard the reason this job exists:
+      # if conda ever resolves back to <3.10 the event-loop regression test stops
+      # covering anything and CI would stay green.
+      - name: Report resolved versions and assert Python 3.10+
+        shell: bash -el {0}
+        run: |
+          python -c "import sys, pykep, numpy; print(sys.version); print(pykep.__version__, numpy.__version__)"
+          python -c "import sys; assert sys.version_info >= (3, 10), f'conda resolved {sys.version_info}, this job must run 3.10+'"
+      - name: Test with pytest
+        shell: bash -el {0}
+        run: pytest -v --timeout=180 paseos/tests/

paseos/activities/activity_manager.py

@@ -148,9 +148,20 @@ async def job():
         # Workaround to avoid error when executed in a Jupyter notebook.
         self._paseos_instance._local_actor._current_activity = name
 
-        # Run activity and processor
-        loop = asyncio.get_event_loop()
-        if loop.is_running():
+        # Run activity and processor. asyncio.run() refuses to nest inside an
+        # already-running loop (e.g. a Jupyter notebook), so ask whether one is
+        # running rather than using get_event_loop(): the latter raises once
+        # asyncio.run() has torn down and unset the loop, which made every
+        # perform_activity() after the first one fail on Python 3.10+.
+        try:
+            asyncio.get_running_loop()
+            loop_is_running = True
+        except RuntimeError:
+            loop_is_running = False
+
+        # Deliberately outside the except block: running the activity inside the
+        # handler would chain any RuntimeError it raises onto "no running event loop".
+        if loop_is_running:
             asyncio.gather(job())
         else:
             asyncio.run(job())

paseos/paseos.py

@@ -189,12 +189,14 @@ def advance_time(
                 time_since_constraint_check += dt
                 self.local_actor.set_time(pk.epoch(self._state.time * pk.SEC2DAY))
 
-                # Check if we should update the status log
-                if self._time_since_previous_log > self._cfg.io.logging_interval:
+                # Check if we should update the status log. The elapsed time has to
+                # accumulate on every step, including the one that logs -- incrementing
+                # only in the else branch cost one extra step per interval, so a 10s
+                # interval at dt=10 logged every 30s.
+                self._time_since_previous_log += dt
+                if self._time_since_previous_log >= self._cfg.io.logging_interval:
                     self.log_status()
                     self._time_since_previous_log = 0
-                else:
-                    self._time_since_previous_log += dt
 
             logger.debug("New time is: " + str(self._state.time) + " s.")
             return max(target_time - self._state.time, 0)

paseos/tests/activity_test.py

@@ -156,3 +156,26 @@ async def on_termination(args):
 
     assert test_value == test_value2
     assert sat1.battery_level_in_Ws >= 505
+
+
+def test_perform_activity_twice_in_a_row():
+    """Two consecutive perform_activity calls have to work.
+
+    Deliberately a sync test: the async tests above run inside an event loop and so
+    take the asyncio.gather branch, which is why this survived. In the sync branch
+    asyncio.run() unsets the current event loop, so the old asyncio.get_event_loop()
+    lookup raised RuntimeError on the second call from Python 3.10 onwards.
+    """
+    sim, _, _ = get_default_instance()
+
+    results = []
+
+    async def func(args):
+        results.append(1)
+
+    sim.register_activity("Testing", activity_function=func, power_consumption_in_watt=10)
+
+    sim.perform_activity("Testing")
+    sim.perform_activity("Testing")
+
+    assert len(results) == 2, "Both activity runs should have executed."

paseos/tests/operations_monitor_test.py

@@ -54,3 +54,38 @@ async def func2(args):
     sim.monitor.plot("state_of_charge")
 
     sim.save_status_log_csv("test.csv")
+
+
+@pytest.mark.parametrize(
+    "dt,logging_interval,expected",
+    [
+        # Interval equal to the timestep: a log on every step.
+        (10.0, 10.0, [10, 20, 30, 40, 50, 60, 70, 80, 90, 100]),
+        # Interval spanning several steps. This is the case that distinguishes the
+        # fix from "log unconditionally": before it, the step that logged did not
+        # count towards the next interval, stretching every gap by one dt.
+        (10.0, 30.0, [10, 40, 70, 100]),
+        (1.0, 10.0, [1, 11, 21, 31, 41, 51, 61, 71, 81, 91]),
+    ],
+)
+def test_logging_interval_is_respected(dt, logging_interval, expected):
+    """The status log has to fire at the configured interval, not a multiple of it."""
+    earth = pk.planet.jpl_lp("earth")
+    sat1 = ActorBuilder.get_actor_scaffold("sat1", SpacecraftActor, pk.epoch(0))
+    ActorBuilder.set_orbit(sat1, [10000000, 0, 0], [0, 8000.0, 0], pk.epoch(0), earth)
+    ActorBuilder.set_power_devices(sat1, 500, 10000, 1)
+
+    cfg = load_default_cfg()
+    cfg.sim.start_time = 0.0
+    cfg.sim.dt = dt
+    cfg.io.logging_interval = logging_interval
+    sim = paseos.init_sim(sat1, cfg)
+
+    sim.advance_time(100.0, 0)
+
+    # Compared with a tolerance: the simulation time accumulates dt step by step,
+    # so exact equality would trip over float representation.
+    timesteps = sim.monitor["timesteps"]
+    assert timesteps == pytest.approx(expected), (
+        f"With dt={dt} and interval={logging_interval} expected logs at {expected}, got {timesteps}"
+    )

pyproject.toml

@@ -8,7 +8,10 @@ version = "0.2.1"
 description = "A package which simulates the space environment for operating multiple spacecraft."
 readme = "README.md"
 license = { file = "LICENSE" }
-requires-python = ">=3.8"
+# Upper bound follows the hard numpy==1.23.5 pin below: numpy 1.23.5 has no
+# wheels for 3.12+ and its sdist does not build there, so an uncapped
+# requires-python advertises installs that cannot possibly succeed.
+requires-python = ">=3.8,<3.12"
 authors = [{ name = "Φ-lab@Sweden", email = "pablo.gomez@esa.int" }]
 keywords = ["spacecraft", "simulation", "space", "satellite", "constellation"]
 classifiers = [