Implement CompositeComponent

miplearn/components/composite.py

@@ -0,0 +1,44 @@
+#  MIPLearn: Extensible Framework for Learning-Enhanced Mixed-Integer Optimization
+#  Copyright (C) 2020, UChicago Argonne, LLC. All rights reserved.
+#  Released under the modified BSD license. See COPYING.md for more details.
+
+from miplearn import Component
+
+
+class CompositeComponent(Component):
+    """
+    A Component which redirects each method call to one or more subcomponents. Useful
+    for breaking down complex components into smaller classes. See RelaxationComponent
+    for a concrete example.
+
+    Parameters
+    ----------
+    children : list[Component]
+        Subcomponents that compose this component.
+    """
+
+    def __init__(self, children):
+        self.children = children
+
+    def before_solve(self, solver, instance, model):
+        for child in self.children:
+            child.before_solve(solver, instance, model)
+
+    def after_solve(self, solver, instance, model, results):
+        for child in self.children:
+            child.after_solve(solver, instance, model, results)
+
+    def fit(self, training_instances):
+        for child in self.children:
+            child.fit(training_instances)
+
+    def lazy_cb(self, solver, instance, model):
+        for child in self.children:
+            child.lazy_cb(solver, instance, model)
+
+    def iteration_cb(self, solver, instance, model):
+        should_repeat = False
+        for child in self.children:
+            if child.iteration_cb(solver, instance, model):
+                should_repeat = True
+        return should_repeat

miplearn/components/tests/test_composite.py

@@ -0,0 +1,57 @@
+#  MIPLearn: Extensible Framework for Learning-Enhanced Mixed-Integer Optimization
+#  Copyright (C) 2020, UChicago Argonne, LLC. All rights reserved.
+#  Released under the modified BSD license. See COPYING.md for more details.
+
+from unittest.mock import Mock, call
+
+from nltk import Model
+
+from miplearn import Component, LearningSolver, Instance
+from miplearn.components.composite import CompositeComponent
+
+
+def test_composite():
+    solver, instance, model = (
+        Mock(spec=LearningSolver),
+        Mock(spec=Instance),
+        Mock(spec=Model),
+    )
+
+    c1 = Mock(spec=Component)
+    c2 = Mock(spec=Component)
+    cc = CompositeComponent([c1, c2])
+
+    # Should broadcast before_solve
+    cc.before_solve(solver, instance, model)
+    c1.before_solve.assert_has_calls([call(solver, instance, model)])
+    c2.before_solve.assert_has_calls([call(solver, instance, model)])
+
+    # Should broadcast after_solve
+    cc.after_solve(solver, instance, model, {})
+    c1.after_solve.assert_has_calls([call(solver, instance, model, {})])
+    c2.after_solve.assert_has_calls([call(solver, instance, model, {})])
+
+    # Should broadcast fit
+    cc.fit([1, 2, 3])
+    c1.fit.assert_has_calls([call([1, 2, 3])])
+    c2.fit.assert_has_calls([call([1, 2, 3])])
+
+    # Should broadcast lazy_cb
+    cc.lazy_cb(solver, instance, model)
+    c1.lazy_cb.assert_has_calls([call(solver, instance, model)])
+    c2.lazy_cb.assert_has_calls([call(solver, instance, model)])
+
+    # Should broadcast iteration_cb
+    cc.iteration_cb(solver, instance, model)
+    c1.iteration_cb.assert_has_calls([call(solver, instance, model)])
+    c2.iteration_cb.assert_has_calls([call(solver, instance, model)])
+
+    # If at least one child component returns true, iteration_cb should return True
+    c1.iteration_cb = Mock(return_value=True)
+    c2.iteration_cb = Mock(return_value=False)
+    assert cc.iteration_cb(solver, instance, model)
+
+    # If all children return False, iteration_cb should return False
+    c1.iteration_cb = Mock(return_value=False)
+    c2.iteration_cb = Mock(return_value=False)
+    assert not cc.iteration_cb(solver, instance, model)