New plugin hook for before reactor construction (#1945)

armi/plugins.py

@@ -267,6 +267,21 @@ def onProcessCoreLoading(core, cs, dbLoad) -> None:
         constructing a Core from Blueprints, or after loading it from a database.
         """
 
+    @staticmethod
+    @HOOKSPEC
+    def beforeReactorConstruction(cs) -> None:
+        """
+        Function to call before the reactor is constructed.
+
+        .. impl:: Plugins can inject code before reactor initialization.
+            :id: I_ARMI_PLUGIN_BEFORE_REACTOR_HOOK
+            :implements: R_ARMI_PLUGIN_BEFORE_REACTOR_HOOK
+
+            This method allows for plugin developers to implement code after settings
+            are loaded but before the reactor is constructed. This hook is called
+            in :py:func:`armi.reactor.reactors.factory`.
+        """
+
     @staticmethod
     @HOOKSPEC
     def defineFlags() -> Dict[str, Union[int, flags.auto]]:

armi/reactor/__init__.py

@@ -51,6 +51,7 @@
 
 from typing import Dict, Callable, Union, TYPE_CHECKING
 
+from armi import materials
 from armi import plugins
 
 if TYPE_CHECKING:
@@ -62,6 +63,19 @@
 class ReactorPlugin(plugins.ArmiPlugin):
     """Plugin exposing built-in reactor components, blocks, assemblies, etc."""
 
+    @staticmethod
+    @plugins.HOOKIMPL
+    def beforeReactorConstruction(cs) -> None:
+        """Just before reactor construction, update the material "registry" with user settings,
+        if it is set. Often it is set by the application.
+        """
+        from armi.settings.fwSettings.globalSettings import (
+            CONF_MATERIAL_NAMESPACE_ORDER,
+        )
+
+        if cs[CONF_MATERIAL_NAMESPACE_ORDER]:
+            materials.setMaterialNamespaceOrder(cs[CONF_MATERIAL_NAMESPACE_ORDER])
+
     @staticmethod
     @plugins.HOOKIMPL
     def defineBlockTypes():

armi/reactor/reactors.py

@@ -19,7 +19,7 @@
 from typing import Optional
 import copy
 
-from armi import materials
+from armi import getPluginManagerOrFail
 from armi import runLog
 from armi.reactor import composites
 from armi.reactor import reactorParameters
@@ -29,7 +29,6 @@
 from armi.reactor.systemLayoutInput import SystemLayoutInput
 from armi.settings.fwSettings.globalSettings import (
     CONF_GEOM_FILE,
-    CONF_MATERIAL_NAMESPACE_ORDER,
     CONF_SORT_REACTOR,
 )
 from armi.utils import directoryChangers
@@ -180,10 +179,8 @@ def factory(cs, bp, geom: Optional[SystemLayoutInput] = None) -> Reactor:
     from armi.reactor import blueprints
 
     runLog.header("=========== Constructing Reactor and Verifying Inputs ===========")
-    # just before reactor construction, update the material "registry" with user settings,
-    # if it is set. Often it is set by the application.
-    if cs[CONF_MATERIAL_NAMESPACE_ORDER]:
-        materials.setMaterialNamespaceOrder(cs[CONF_MATERIAL_NAMESPACE_ORDER])
+    getPluginManagerOrFail().hook.beforeReactorConstruction(cs=cs)
+
     r = Reactor(cs.caseTitle, bp)
 
     if cs[CONF_GEOM_FILE]:

armi/tests/test_plugins.py

@@ -56,6 +56,15 @@ def getAxialExpansionChanger() -> type[SillyAxialExpansionChanger]:
         return SillyAxialExpansionChanger
 
 
+class BeforeReactorPlugin(plugins.ArmiPlugin):
+    """Trivial plugin that implements the before reactor construction hook."""
+
+    @staticmethod
+    @plugins.HOOKIMPL
+    def beforeReactorConstruction(cs) -> None:
+        cs.beforeReactorConstructionFlag = True
+
+
 class TestPluginRegistration(unittest.TestCase):
     def setUp(self):
         """
@@ -119,6 +128,20 @@ def test_axialExpansionHook(self):
         # that plugin's axial expander
         self.assertIs(second, SillyAxialExpansionChanger)
 
+    def test_beforeReactorConstructionHook(self):
+        """Test that plugin hook successfully injects code before reactor initialization.
+
+        .. test:: Capture code in the beforeReactorConstruction hook from reactor construction being carried out.
+            :id: T_ARMI_PLUGIN_BEFORE_REACTOR_HOOK
+            :tests: R_ARMI_PLUGIN_BEFORE_REACTOR_HOOK
+        """
+        pm = getPluginManagerOrFail()
+        pm.register(BeforeReactorPlugin)
+        o = loadTestReactor(
+            TEST_ROOT, inputFileName="smallestTestReactor/armiRunSmallest.yaml"
+        )[0]
+        self.assertTrue(o.cs.beforeReactorConstructionFlag)
+
 
 class TestPluginBasics(unittest.TestCase):
     def test_defineParameters(self):

doc/release/0.4.rst

@@ -14,11 +14,13 @@ New Features
 #. Adding ``--skip-inspection`` flag to ``CompareCases`` CLI. (`PR#1842 <https://github.com/terrapower/armi/pull/1842>`_)
 #. Allow merging a component with zero area into another component (`PR#1858 <https://github.com/terrapower/armi/pull/1858>`_)
 #. Use ``Block.getNumPins()`` in ``HexBlock._rotatePins()``. (`PR#1859 <https://github.com/terrapower/armi/pull/1859>`_)
-#. Provide utilities for determining location of a rotated object in a hexagonal lattice (``getIndexOfRotatedCell``). (`PR#1846 <https://github.com/terrapower/armi/1846`)
+#. Provide utilities for determining location of a rotated object in a hexagonal lattice (``getIndexOfRotatedCell``). (`PR#1846 <https://github.com/terrapower/armi/1846>`_)
 #. Allow merging a component with zero area into another component. (`PR#1858 <https://github.com/terrapower/armi/pull/1858>`_)
 #. Provide ``Parameter.hasCategory`` for quickly checking if a parameter is defined with a given category. (`PR#1899 <https://github.com/terrapower/armi/pull/1899>`_)
 #. Provide ``ParameterCollection.where`` for efficient iteration over parameters who's definition matches a given condition. (`PR#1899 <https://github.com/terrapower/armi/pull/1899>`_)
 #. Plugins can provide the ``getAxialExpansionChanger`` hook to customize axial expansion. (`PR#1870 <https://github.com/terrapower/armi/pull/1870`_)
+#. Plugins can provide the ``getAxialExpansionChanger`` hook to customize axial expansion. (`PR#1870 <https://github.com/terrapower/armi/pull/1870>`_)
+#. New plugin hook ``beforeReactorConstruction`` added to enable plugins to process case settings before reactor init. (`PR#1945 <https://github.com/terrapower/armi/pull/1945>`_)
 #. Provide ``Block.getInputHeight`` for determining the height of a block from blueprints. (`PR#1927 <https://github.com/terrapower/armi/pull/1927`_)
 #. TBD
 
@@ -35,7 +37,7 @@ API Changes
 #. Allowing for unknown Flags when opening a DB. (`PR#1844 <https://github.com/terrapower/armi/pull/1835>`_)
 #. Removing ``Assembly.doubleResolution()``. (`PR#1951 <https://github.com/terrapower/armi/pull/1951>`_)
 #. Removing ``assemblyLists.py`` and the ``AssemblyList`` class. (`PR#1891 <https://github.com/terrapower/armi/pull/1891>`_)
-#. Removing ``Assembly.rotatePins`` and ``Block.rotatePins``. Prefer ``Assembly.rotate`` and ``Block.rotate``. (`PR#1846 <https://github.com/terrapower/armi/1846`_)
+#. Removing ``Assembly.rotatePins`` and ``Block.rotatePins``. Prefer ``Assembly.rotate`` and ``Block.rotate``. (`PR#1846 <https://github.com/terrapower/armi/1846>`_)
 #. Transposing ``pinMgFluxes`` parameters so that leading dimension is pin index (`PR#1937 <https://github.com/terrapower/armi/pull/1937>`)
 #. Removing ``globalFluxInterface.DoseResultsMapper`` class (`PR#1952 <https://github.com/terrapower/armi/pull/1952>`)
 #. TBD