Source code for armi.plugins

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r"""
Plugins allow various built-in or external functionality to be brought into the ARMI ecosystem.

This module defines the hooks that may be defined within plugins. Plugins are ultimately
incorporated into a :py:class:`armi.pluginManager.ArmiPluginManager`, which live inside
of a :py:class:`armi.apps.App` object.

The ``ArmiPluginManager`` is derived from the ``PluginManager`` class provided by the
``pluggy`` package, which provides a registry of known plugins. Rather than create one
directly, we use the :py:func:`armi.plugins.getNewPluginManager()` function, which
handles some of the setup for us.

From a high-altitude perspective, the plugins provide numerous "hooks", which allow for
ARMI to be extended in various ways. Some of these extensions are subtle and play a part
in how certain ARMI components are initialized or defined. As such, it is necessary to
register most plugins before some parts of ARMI are imported or exercised in a
meaningful way. These requirements are in flux, and will ultimately constitute part of
the specification of the ARMI plugin architecture. For now, to be safe, plugins should
be registered as soon as possible.

After forming the ``PluginManager``, the plugin hooks can be accessed through the
``hook`` attribute. E.g.::

    >>> armi.getPluginManagerOrFail().hook.exposeInterfaces(cs=cs)

Don't forget to use the keyword argument form for all arguments to hooks; ``pluggy``
requires them to enforce hook specifications.

The :py:class:`armi.apps.App` class serves as the primary storage location of the
PluginManager, and also provides some methods to get data out of the plugins more
ergonomically than through the hooks themselves.

Some things you may want to bring in via a plugin includes:

- :py:mod:`armi.settings` and their validators
- :py:mod:`armi.reactor.components` for custom geometry
- :py:mod:`armi.reactor.flags` for custom reactor components
- :py:mod:`armi.interfaces` to define new calculation sequences and interactions with
  new codes
- :py:mod:`armi.reactor.parameters` to represent new physical state on the reactor
- :py:mod:`armi.materials` for custom materials
- Elements of the :py:mod:`armi.gui`
- :py:mod:`armi.operators` for adding new operations on reactor models
- :py:mod:`armi.cli` for adding new operations on input files

Warning
-------

The plugin system was developed to support improved collaboration.  It is new and should
be considered under development. The API is subject to change as the version of the ARMI
framework approaches 1.0.

Notes
-----
Due to the nature of some of these components, there are a couple of restrictions on
the order in which things can be imported (lest we endeavor to redesign them
considerably). Examples:

  - Parameters: All parameter definitions must be present before any ``ArmiObject``
    objects are instantiated. This is mostly by choice, but also makes the most sense,
    because the ``ParameterCollection`` s are instance attributes of an ``ArmiObject``,
    which in turn use ``Parameter`` objects as *class* attributes. We should know
    what class attributes we have before making instances.

  - Blueprints: Since blueprints should be extendable with new sections, we must also
    be able to provide new *class* attributes to extend their behavior. This is
    because blueprints use the yamlize package, which uses class attributes to define
    much of the class's behavior through metaclassing. Therefore, we need to be able
    to import all plugins *before* importing blueprints.

Plugins are currently stateless. They do not have ``__init__()`` methods, and when they are
registered with the PluginMagager, the PluginManager gets the Plugin's class object
rather than an instance of that class. Also notice that all of the hooks are
``@staticmethod``\ s. As a result, they can be called directly off of the class object,
and only have access to the state passed into them to perform their function. This is a
deliberate design choice to keep the plugin system simple and to preclude a large class
of potential bugs. At some point it may make sense to revisit this.


Other customization points
--------------------------
While the Plugin API is the main place for ARMI framework customization, there are
several other areas where ARMI may be extended or customized. These typically pre-dated
the Plugin-based architecture, and as the need arise may be migrated to here.

 - Component types: Component types are registered dynamically through some metaclass
   magic, found in :py:class:`armi.reactor.components.component.ComponentType` and
   :py:class:`armi.reactor.composites.CompositeModelType`. Simply defining a new
   Component subclass should register it with the appropriate ARMI systems. While this
   is convenient, it does lead to potential issues, as the behavior of ARMI becomes
   sensitive to module import order and the like; the containing module needs to be
   imported before the registration occurs, which can be surprising.

 - Interface input files: Interfaces used to be discovered dynamically, rather than
   explicitly as they are now in the :py:meth:`armi.plugins.ArmiPlugin.exposeInterfaces`
   plugin hook. Essentially they functioned as ersatz plugins. One of the ways that they
   would customize ARMI behavior is through the
   :py:meth:`armi.physics.interface.Interface.specifyInputs` static method, which is
   still used to determine inter-Case dependencies and support cloning and hashing Case
   inputs. Going forward, this approach will likely be deprecated in favor of a plugin
   hook.

 - Fuel handler logic: The
   :py:class:`armi.physics.fuelCycle.fuelHandlers.FuelHandlerInterface` supports
   customization through the dynamic loading of fuel handler logic modules, based on
   user settings. This also predated the plugin infrastructure, and may one day be
   replaced with plugin-based fuel handler logic.
"""
from typing import Dict, Union

import pluggy

from armi import pluginManager
from armi.utils import flags


HOOKSPEC = pluggy.HookspecMarker("armi")
HOOKIMPL = pluggy.HookimplMarker("armi")


[docs]class ArmiPlugin: """ An ArmiPlugin provides a namespace to collect hook implementations provided by a single "plugin". This API is incomplete, unstable, and expected to change dramatically! """
[docs] @staticmethod @HOOKSPEC def exposeInterfaces(cs): """ Function for exposing interface(s) to other code. Returns ------- list Tuples containing: - The insertion order to use when building an interface stack, - an implementation of the Interface class - a dictionary of kwargs to pass to an Operator when adding an instance of the interface class If no Interfaces should be active given the passed case settings, this should return an empty list. """
[docs] @staticmethod @HOOKSPEC def defineParameters(): """ Function for defining additional parameters. Returns ------- dict Keys should be subclasses of ArmiObject, values being a ParameterDefinitionCollection should be added to the key's perameter definitions. Example ------- >>> pluginBlockParams = parameters.ParameterDefinitionCollection() >>> with pluginBlockParams.createBuilder() as pb: ... pb.defParam("plugBlkP1", ...) ... # ... ... >>> pluginAssemParams = parameters.ParameterDefinitionCollection() >>> with pluginAssemParams.createBuilder() as pb: ... pb.defParam("plugAsmP1", ...) ... # ... ... >>> return { ... blocks.Block: pluginBlockParams, ... assemblies.Assembly: pluginAssemParams ... } """
[docs] @staticmethod @HOOKSPEC def afterConstructionOfAssemblies(assemblies, cs): """ Function to call after a set of assemblies are constructed. This hook can be used to: - Verify that all assemblies satisfy constraints imposed by active interfaces and plugins - Apply modifications to Assemblies based on modeling options and active interfaces Implementers may alter the state of the passed Assembly objects. Returns ------- None """
[docs] @staticmethod @HOOKSPEC def onProcessCoreLoading(core, cs): """ Function to call whenever a Core object is newly built. This is usually used to set initial parameter values from inputs, either after constructing a Core from Blueprints, or after loading it from a database. """
[docs] @staticmethod @HOOKSPEC def defineFlags() -> Dict[str, Union[int, flags.auto]]: """ Function to provide new Flags definitions. This allows a plugin to provide novel values for the Flags system. Implementations should return a dictionary mapping flag names to their desired numerical values. In most cases, no specific value is needed, in which case :py:class:`armi.utils.flags.auto` should be used. Flags should be added to the ARMI system with great care; flag values for each object are stored in a bitfield, so each additional flag increases the width of the data needed to store them. Also, due to the `what things are` interpretation of flags (see :py:mod:`armi.reactor.flags`), new flags should probably refer to novel design elements, rather than novel behaviors. See Also -------- armi.reactor.flags Example ------- >>> def defineFlags(): ... return { ... "FANCY": armi.utils.flags.auto() ... } """
[docs] @staticmethod @HOOKSPEC def defineBlockTypes(): """ Function for providing novel Block types from a plugin. This should return a list of tuples containing ``(compType, blockType)``, where ``blockType`` is a new ``Block`` subclass to register, and ``compType`` is the corresponding ``Component`` type that should activate it. For instance a ``HexBlock`` would be created when the largest component is a ``Hexagon``:: return [(Hexagon, HexBlock)] """
[docs] @staticmethod @HOOKSPEC def defineAssemblyTypes(): """ Function for providing novel Assembly types from a plugin. This should return a list of tuples containing ``(blockType, assemType)``, where ``assemType`` is a new ``Assembly`` subclass to register, and ``blockType`` is the corresponding ``Block`` subclass that, if present in the assembly, should trigger it to be of the corresponding ``assemType``. .. warning:: The utility of subclassing Assembly is suspect, and may soon cease to be supported. In practice, Assembly subclasses provide very little functionality beyond that on the base class, and even that functionality can probably be better suited elsewhere. Moving this code around would let us eliminate the specialized Assembly subclasses altogether. In such a case, this API will be removed from the framework. """
[docs] @staticmethod @HOOKSPEC def defineBlueprintsSections(): """ Return new sections for the blueprints input method. This hook allows plugins to extend the blueprints functionality with their own sections. Returns ------- list (name, section, resolutionMethod) tuples, where: - name : The name of the attribute to add to the Blueprints class; this should be a valid Python identifier. - section : An instance of ``yaml.Attribute`` defining the data that is described by the Blueprints section. - resolutionMethod : A callable that takes a Blueprints object and case settings as arguments. This will be called like an unbound instance method on the passed Blueprints object to initialize the state of the new Blueprints section. Notes ----- Most of the sections that a plugin would want to add may be better served as settings, rather than blueprints sections. These sections were added to the blueprints mainly because the schema is more flexible, allowing namespaces and hierarchical collections of settings. Perhaps in the near future it would make sense to enhance the settings system to support these features, moving the blueprints extensions out into settings. This is discussed in more detail in T1671. """
[docs] @staticmethod @HOOKSPEC def defineEntryPoints(): """ Return new entry points for the ARMI CLI This hook allows plugins to provide their own ARMI entry points, which each serve as a command in the command-line interface. Returns ------- list class objects which derive from the base EntryPoint class. """
[docs] @staticmethod @HOOKSPEC def defineSettings(): """ Define configuration settings for this plugin. This hook allows plugins to provide their own configuration settings, which can participate in the :py:class:`armi.settings.caseSettings.CaseSettings`. Plugins may provide entirely new settings to what are already provided by ARMI, as well as new options or default values for existing settings. For instance, the framework provides a ``neutronicsKernel`` setting for selecting which global physics solver to use. Since we wish to enforce that the user specify a valid kernel, the settings validator will check to make sure that the user's requested kernel is among the available options. If a plugin were to provide a new neutronics kernel (let's say MCNP), it should also define a new option to tell the settings system that ``"MCNP"`` is a valid option. Returns ------- list A list of Settings, Options, or Defaults to be registered. See also -------- armi.physics.neutronics.NeutronicsPlugin.defineSettings armi.settings.setting.Setting armi.settings.setting.Option armi.settings.setting.Default """ return []
[docs] @staticmethod @HOOKSPEC def defineSettingsValidators(inspector): """ Define the high-level settings input validators by adding them to an inspector. Parameters ---------- inspector : :py:class:`armi.operators.settingsValidation.Inspector` instance The inspector to add queries to. See note below, this is not ideal. Notes ----- These are higher-level than the input-level SCHEMA defined in :py:meth:`defineSettings` and are intended to be used for more complex cross-plugin info. We'd prefer to not manipulate objects passed in directly, but rather have the inspection happen in a measureable hook. This would help find misbehaving plugins. See Also -------- armi.operators.settingsValidation.Inspector : Runs the queries Returns ------- list Query objects to attach """
[docs] @staticmethod @HOOKSPEC def defineCaseDependencies(case, suite): r""" Function for defining case dependencies. Some Cases depend on the results of other ``Case``\ s in the same ``CaseSuite``. Which dependencies exist, and how they are discovered depends entirely on the type of analysis and active interfaces, etc. This function allows a plugin to inspect settings and declare dependencies between the passed ``case`` and any other cases in the passed ``suite``. Parameters ---------- case : Case The specific case for which we want to find dependencies. suite : CaseSuite A CaseSuite object to which the Case and other potential dependencies belong. Returns ------- dependencies : set of Cases This should return a set containing ``Case`` objects that are considered dependencies of the passed ``case``. They should be members of the passed ``suite``. """
[docs] @staticmethod @HOOKSPEC def defineGuiWidgets(): """ Define which settings should go in the GUI. Rather than making widgets here, this simply returns metadata as a nested dictionary saying which tab to put which settings on, and a little bit about how to group them. Returns ------- widgetData : list of dict Each dict is nested. First level contains the tab name (e.g. 'Global Flux'). Second level contains a box name. Third level contains help and a list of setting names See Also -------- armi.gui.submitter.layout.abstractTab.AbstractTab.addSectionsFromPlugin : uses data structure Example ------- >>> widgets = { ... 'Global Flux': { ... 'MCNP Solver Settings': { ... 'help': "Help message" ... 'settings': [ ... "mcnpAddTallies", ... "useSrctp", ... ] ... } ... } ... } """
[docs] @staticmethod @HOOKSPEC def getOperatorClassFromRunType(runType: str): """Return an Operator subclass if the runType is recognized by this plugin."""
[docs] @staticmethod @HOOKSPEC def defineParameterRenames(): """ Return a mapping from old parameter names to new parameter names. Occasionally, it may become necessary to alter the name of an existing parameter. This can lead to frustration when attempting to load from old database files that use the previous name. This hook allows a plugin to define mappings from the old name to the new name, allowing the old database to be read in and translated to the new parameter name. The following rules are followed when applying these renames: * When state is loaded from a database, if the parameter name in the database file is found in the rename dictionary, it will be mapped to that renamed parameter. * If the renamed parameter is found in the renames, then it will be mapped again to new parameter name. This process is repeated until there are no more renames left. This allows for parameters to be renamed multiple times, and for a database from several generations prior to still be readable, so long as the history of renames is intact. * If at the end of the above process, the parameter name is not a defined parameter for the appropriate ``ArmiObject`` type, an exception is raised. * If any of the ``renames`` keys match any currently-defined parameters, an exception is raised. * If any of the ``renames`` collide with another plugin's ``renames``, an exception is raised. Returns ------- renames : dict Keys should be an old parameter name, where the corresponding values are the new parameter name. Example ------- The following would allow databases with values for either ``superOldParam`` or ``oldParam`` to be read into ``currentParam``:: return {"superOldParam": "oldParam", "oldParam": "currentParam"} """
[docs] @staticmethod @HOOKSPEC def mpiActionRequiresReset(cmd) -> bool: """ Flag indicating when a reactor reset is required. Commands are sent through operators either as strings (old) or as MpiActions (newer). After some are sent, the reactor must be reset. This hook says when to reset. The reset operation is a (arguably suboptimal) response to some memory issues in very large and long-running cases. Parameters ---------- cmd : str or MpiAction The ARMI mpi command being sent Returns ------- bool See Also -------- armi.operators.operatorMPI.OperatorMPI.workerOperate : Handles these flags """
[docs] @staticmethod @HOOKSPEC def getReportContents(r, cs, report, stage, blueprint) -> None: """ To generate a report. For more information, see :doc:`/developer/reports`. Parameters ---------- r : Reactor cs : Settings report : ReportContent Report object to add contents to stage : ReportStage begin/standard/or end (stage of the report for when inserting BOL vs. EOL content) blueprint : Blueprint, optional for a reactor (if None, only partial contents created) """
[docs]def getNewPluginManager() -> pluginManager.ArmiPluginManager: """ Return a new plugin manager with all of the hookspecs pre-registered. """ pm = pluginManager.ArmiPluginManager("armi") pm.add_hookspecs(ArmiPlugin) return pm
[docs]def collectInterfaceDescriptions(mod, cs): """ Adapt old-style describeInterfaces to the new plugin interface Old describeInterfaces implementations would return an interface class and kwargs for adding to an operator. Now we expect an ORDER as well. This takes a module and case settings and staples the module's ORDER attribute to the tuple and checks to make sure that a None is replaced by an empty list. """ from armi import interfaces val = mod.describeInterfaces(cs) if val is None: return [] if isinstance(val, list): return [ interfaces.InterfaceInfo(mod.ORDER, klass, kwargs) for klass, kwargs in val ] klass, kwargs = val return [interfaces.InterfaceInfo(mod.ORDER, klass, kwargs)]
[docs]class PluginError(RuntimeError): """ Special exception class for use when a plugin appears to be non-conformant. These should always come from some form of programmer error, and indicates conditions such as: - A plugin improperly implementing a hook, when possible to detect. - A collision between components provided by plugins (e.g. two plugins providing the same Blueprints section) """