How to create unitary tests
Kratos Multiphysics has a mechanism to automatically test your code called "KratosUnittest". If you are familiar with python, this module is basically an extension of Unittest[1] and you can expect to find every functionality that exists on in as well in KratosUnittest.
In order for your application to be robust, is recommended that you add unittests to it. Here we present some guidelines on how to do it.
Contents |
How to run tests
Kratos unittest are executed using the "run_tests.py" script located in the "kratos/kratos/python_scripts" folder.
Usage is the following:
python run_tests.py
you can specify the following options:
-l,--level: Select the suit. Values: "All", "Nighlty", "Small"(default)
-v,--vervosity: Select the vervosity level of the output. Values: 0, 1 (default) , 2
-a,--applications: List of applications to run separated by ":". For example "-a KratosKore:IncompresibleFluidApplication"
All applications compiled are run by default.
Basic structure
Tests are defined in a python script. To keep tests organized we recommend you to create the tests in your "application/tests/" directory.
Tests are organized in suites. Suites are collection of tests that will be run together as a package. In Kratos, we define three basic suites:
- All: which should contain all the tests
- Nighlty: which should contain a set of tests that could be executed in less than 10 min
- Small: which should contain a set of tests that could be executed in less than 1 min
All applications should implement this packages as they can be automatically run, for example in the "nighlty" runs.
In order to add tests you should create at least a couple of files, one to define the tests
and one to define the suits:
"application/tests/test_NAME_OF_OUR_APPLICATION.py"
for example:
kratos/applications/example_application/tests/test_example_application.py
General structure
This file will define the suites to run the tests. We define three different levels of suites in kratos:
- All: which should contain all the tests
- Nighlty: which should contain a set of tests that could be executed in less than 10 min
- Small: which should contain a set of tests that could be executed in less than 1 min
In order to add test to some of these suits, one can do it as shown in this example:
from __future__ import print_function, absolute_import, division
# import Kratos
from KratosMultiphysics import *
# Import Kratos "wrapper" for unittests
import KratosMultiphysics.KratosUnittest as KratosUnittest
# Import the tests o test_classes to create the suites. For example
from test_my_app_example_tests_1 import TestCase1 as TestCase1
from test_my_app_example_tests_2 import TestCase2 as TestCase2
def AssambleTestSuites():
Populates the test suites to run.
Populates the test suites to run. At least, it should pupulate the suites:
"small", "nighlty" and "all"
Return
------
suites: A dictionary of suites
The set of suites with its test_cases added.
# Get the already defined suits
suites = KratosUnittest.KratosSuites
# Get the small suit and populate it with some tests from TestCase1 and TestCase2
smallSuite = suites['small']
smallSuite.addTest(TestCase1('test_example_small_boo_1'))
smallSuite.addTest(TestCase2('test_example_small_foo_1'))
# Get the small suit and populate it with some tests from TestCase1 and TestCase2
nightSuite = suites['nightly']
smallSuite.addTest(TestCase1('test_example_nightly_boo_1'))
smallSuite.addTest(TestCase1('test_example_nightly_boo_2'))
smallSuite.addTest(TestCase2('test_example_nightly_foo_1'))
# Get the small suit and populate it with all tests from TestCase1 and TestCase2
allSuite = suites['all']
allSuite.addTests(
KratosUnittest.TestLoader().loadTestsFromTestCases([
TestCase1,
TestCase2
])
)
# Return the suites
return suites
# The main function executes the tests
if __name__ == '__main__':
KratosUnittest.runTests(AssambleTestSuites())
Structure for examples
In order to compute some examples (the examples that use to be located in the folder "test_examples") some additional considerations must to be taken into account. These considerations can be observed in the following example that is located in the StructuralMechanicsApplication. In order to compute a Patch Test, with bending and membrane behaviours, the following files has been considered, first the main file that will be the one launched.
# import Kratos
from KratosMultiphysics import *
from KratosMultiphysics.SolidMechanicsApplication import *
from KratosMultiphysics.StructuralMechanicsApplication import *
# Import Kratos "wrapper" for unittests
import KratosMultiphysics.KratosUnittest as KratosUnittest
# Import the tests o test_classes to create the suits
from SmallTests import SprismTests as TSprismTests
def AssambleTestSuites():
Populates the test suites to run.
Populates the test suites to run. At least, it should pupulate the suites:
"small", "nighlty" and "all"
Return
------
suites: A dictionary of suites
The set of suites with its test_cases added.
suites = KratosUnittest.KratosSuites
# Create a test suit with the selected tests (Small tests):
smallSuite = suites['small']
smallSuite.addTest(TSprismTests('test_MembranePacth'))
smallSuite.addTest(TSprismTests('test_BendingPacth'))
# Create a test suit with the selected tests plus all small tests
nightSuite = suites['nightly']
nightSuite.addTests(smallSuite)
# Create a test suit that contains all the tests:
allSuite = suites['all']
allSuite.addTests(
KratosUnittest.TestLoader().loadTestsFromTestCases([
TSprismTests
])
)
return suites
if __name__ == '__main__':
KratosUnittest.runTests(AssambleTestSuites())
The following can be added as commentary to clarify what the script is doing:
- The tests are added using the string 'test_nametest' from the imported class.
- Nightly should consider at least all the small test, in the same way all should consider all the nightly test.
The following corresponds with the Script that content the test examples:
# Import Kratos
from KratosMultiphysics import *
from KratosMultiphysics.SolidMechanicsApplication import *
from KratosMultiphysics.StructuralMechanicsApplication import *
# Import KratosUnittest
import KratosMultiphysics.KratosUnittest as KratosUnittest
# Additional imports
import constitutive_law_python_utility as constitutive_law_utils
def GetFilePath(fileName):
return os.path.dirname(__file__) + "/" + fileName
class SprismTests(KratosUnittest.TestCase):
def setUp(self):
# Modelpart for the solid
model_part = ModelPart("StructuralPart")
model_part.AddNodalSolutionStepVariable(ALPHA_EAS)
model_part.AddNodalSolutionStepVariable(DISPLACEMENT)
model_part.AddNodalSolutionStepVariable(REACTION)
# Initialize GiD I/O
input_file_name = GetFilePath("SPRISM3D6N/patch_test")
# Reading the fluid part
model_part_io_fluid = ModelPartIO(input_file_name)
model_part_io_fluid.ReadModelPart(model_part)
# Find neighbours if required
sprism_neighbour_search = SprismNeighbours(model_part)
sprism_neighbour_search.Execute()
# Setting up the buffer size
model_part.SetBufferSize(3)
# Adding dofs
for node in model_part.Nodes:
node.AddDof(DISPLACEMENT_X, REACTION_X)
node.AddDof(DISPLACEMENT_Y, REACTION_Y)
node.AddDof(DISPLACEMENT_Z, REACTION_Z)
# Set the constitutive law
constitutive_law = constitutive_law_utils.ConstitutiveLawUtility(model_part, 3);
constitutive_law.Initialize();
max_iters = 30
linear_solver = SkylineLUFactorizationSolver()
# Create solver
builder_and_solver = ResidualBasedBuilderAndSolver(linear_solver)
mechanical_scheme = ResidualBasedStaticScheme()
mechanical_convergence_criterion = ResidualCriteria(1e-4, 1e-4)
self.mechanical_solver = ResidualBasedNewtonRaphsonStrategy(
model_part,
mechanical_scheme,
linear_solver,
mechanical_convergence_criterion,
builder_and_solver,
max_iters,
False ,
True,
True)
self.mechanical_solver.SetEchoLevel(0)
self.mechanical_solver.Initialize()
self.model_part = model_part
def test_MembranePacth(self):
step = 0
time = 0.0
Dt = 1.0
final_time = 1.0
# Add BC
for node in self.model_part.Nodes:
if (node.X >2.40000e-01 -1.0e-5) | (node.Y > 1.20000e-01 -1.0e-5) | (node.X < 1.0e-5) | (node.Y < 1.0e-5):
node.Fix(DISPLACEMENT_X)
node.SetSolutionStepValue(
DISPLACEMENT_X,
0,
1.0e-7 * (node.X + node.Y / 2))
node.Fix(DISPLACEMENT_Y)
node.SetSolutionStepValue(
DISPLACEMENT_Y,
0,
1.0e-7 * (node.Y + node.X / 2))
while(time <= final_time):
self.model_part.CloneTimeStep(time)
time += Dt
step += 1
self.mechanical_solver.Solve()
for node in self.model_part.Nodes:
value = node.GetSolutionStepValue(DISPLACEMENT_X,0)
self.assertAlmostEqual(value, 1.0e-7 * (node.X + node.Y / 2))
value = node.GetSolutionStepValue(DISPLACEMENT_Y,0)
self.assertAlmostEqual(value, 1.0e-7 * (node.Y + node.X / 2))
def test_BendingPacth(self):
step = 0
time = 0.0
Dt = 1.0
final_time = 1.0
# Add BC
for node in self.model_part.Nodes:
if (node.X >2.40000e-01 -1.0e-5) | (node.Y > 1.20000e-01 -1.0e-5) | (node.X < 1.0e-5) | (node.Y < 1.0e-5):
node.Fix(DISPLACEMENT_X)
node.SetSolutionStepValue(
DISPLACEMENT_X, 0,
-1.0e-7 * (node.Z - 0.0005) * (node.X + node.Y / 2))
node.Fix(DISPLACEMENT_Y)
node.SetSolutionStepValue(
DISPLACEMENT_Y, 0,
-1.0e-7 * (node.Z - 0.0005) * (node.Y + node.X / 2))
node.Fix(DISPLACEMENT_Z)
node.SetSolutionStepValue(
DISPLACEMENT_Z, 0,
0.5 * 1.0e-7 * (node.X ** 2 + node.X * node.Y + node.Y ** 2))
while(time <= final_time):
self.model_part.CloneTimeStep(time)
time += Dt
step += 1
self.mechanical_solver.Solve()
for node in self.model_part.Nodes:
value = node.GetSolutionStepValue(DISPLACEMENT_X,0)
self.assertAlmostEqual(
value,
-1.0e-7 * (node.Z - 0.0005) * (node.X + node.Y / 2))
value = node.GetSolutionStepValue(DISPLACEMENT_Y,0)
self.assertAlmostEqual(
value,
-1.0e-7 * (node.Z - 0.0005) * (node.Y + node.X / 2))
value = node.GetSolutionStepValue(DISPLACEMENT_Z,0)
self.assertAlmostEqual(value,
0.5 * 1.0e-7 * (node.X ** 2 + node.X * node.Y + node.Y **2 ))
def tearDown(self):
pass
You can download this example from here[2]
Some interesting comments to add to clarify:
- The solver should be created inside the setup
- To be recognized all the test need to have the name "test_" at the beginning of the definition ("test_MembranePacth" and "test_BendingPacth" in this example).
- The "tearDown" doesn't do anything, it just close files, clear memory...
- "imports" should be at the beginning of the file to avoid conflicts
- NO PRINTS, is not necessary, the unittest already prints all the necessary information.
Some common commands in Unittest
The link[3] contents the commands that can be used with the original Unittest from Python, not all the commands from the python Unittest are available in Kratos right now, but they will be available in a near future. The following are the most common and essential commands in Kratos Unittest:
- assertTrue/assertFalse:They check if the two inputs are true or false respectively.
- assertEqual: Check if the two inputs are exactly equal, if the inputs are doubles it is recommended to use the next assert, in order to avoid precision errors.
- assertAlmostEqual: Check if the solution is almost equal in the two inputs, with a certain precision (check the unittest python wiki for more details[4])
