chore: drain active calls before rolling updates

api/tests/test_active_calls.py

@@ -0,0 +1,53 @@
+"""Unit tests for the per-worker active-call registry (deploy draining).
+
+The registry backs GET /api/v1/health/active-calls, which scripts/rolling_update.sh
+(and a k8s preStop hook) polls to wait for live calls to finish before stopping a
+worker. The guarantees that matter for draining: register/unregister are
+idempotent, and the count only reaches zero when every registered run is gone.
+"""
+
+from api.services.pipecat import active_calls
+
+
+def setup_function():
+    # Module-level state — start each test from an empty registry.
+    active_calls._active_run_ids.clear()
+
+
+def test_starts_empty():
+    assert active_calls.active_call_count() == 0
+
+
+def test_register_counts_distinct_runs():
+    active_calls.register_active_call(1)
+    active_calls.register_active_call(2)
+    assert active_calls.active_call_count() == 2
+
+
+def test_register_is_idempotent():
+    # Registering the same run twice must not double-count, or the count could
+    # never drain to zero.
+    active_calls.register_active_call(1)
+    active_calls.register_active_call(1)
+    assert active_calls.active_call_count() == 1
+
+
+def test_unregister_removes_run():
+    active_calls.register_active_call(1)
+    active_calls.register_active_call(2)
+    active_calls.unregister_active_call(1)
+    assert active_calls.active_call_count() == 1
+
+
+def test_unregister_unknown_run_is_a_noop():
+    # discard() semantics: unregistering a run that was never registered (or was
+    # already removed) is safe and cannot push the count negative.
+    active_calls.unregister_active_call(999)
+    assert active_calls.active_call_count() == 0
+
+
+def test_full_lifecycle_drains_to_zero():
+    active_calls.register_active_call(42)
+    assert active_calls.active_call_count() == 1
+    active_calls.unregister_active_call(42)
+    assert active_calls.active_call_count() == 0