Add cached app/config accessors in bionetgen.main

bionetgen/main.py

@@ -1,3 +1,5 @@
+import functools
+
 import cement
 import bionetgen as bng
 from cement.core.exc import CaughtSignal
@@ -625,6 +627,24 @@ class Meta:
         label = "bionetgen"
 
 
+@functools.lru_cache(maxsize=None)
+def get_default_app():
+    """Return a configured BioNetGen cement app, initialized once per process."""
+    app = BioNetGen()
+    app.setup()
+    return app
+
+
+def get_conf():
+    """Return the bionetgen config section from the shared app."""
+    return get_default_app().config["bionetgen"]
+
+
+def get_default_bng_path():
+    """Return the default BNG2.pl path from config."""
+    return get_conf()["bngpath"]
+
+
 def main():
     with BioNetGen() as app:
         try:

tests/test_main_accessors.py

@@ -0,0 +1,45 @@
+from unittest.mock import MagicMock, patch
+
+
+def test_get_default_app_is_cached():
+    from bionetgen import main as main_module
+
+    main_module.get_default_app.cache_clear()
+    fake_app = MagicMock()
+
+    with patch.object(main_module, "BioNetGen", return_value=fake_app) as mock_app_cls:
+        app1 = main_module.get_default_app()
+        app2 = main_module.get_default_app()
+
+    assert app1 is fake_app
+    assert app2 is fake_app
+    mock_app_cls.assert_called_once_with()
+    fake_app.setup.assert_called_once_with()
+    main_module.get_default_app.cache_clear()
+
+
+def test_get_conf_uses_cached_default_app():
+    from bionetgen import main as main_module
+
+    main_module.get_default_app.cache_clear()
+    fake_app = MagicMock()
+    fake_app.config = {"bionetgen": {"bngpath": "/fake/BNG2.pl", "other": "value"}}
+
+    with patch.object(main_module, "BioNetGen", return_value=fake_app) as mock_app_cls:
+        conf1 = main_module.get_conf()
+        conf2 = main_module.get_conf()
+
+    assert conf1 == {"bngpath": "/fake/BNG2.pl", "other": "value"}
+    assert conf2 is conf1
+    mock_app_cls.assert_called_once_with()
+    fake_app.setup.assert_called_once_with()
+    main_module.get_default_app.cache_clear()
+
+
+def test_get_default_bng_path_reads_bngpath_from_config():
+    from bionetgen import main as main_module
+
+    with patch.object(
+        main_module, "get_conf", return_value={"bngpath": "/tmp/BNG2.pl"}
+    ):
+        assert main_module.get_default_bng_path() == "/tmp/BNG2.pl"