Testing Spring Controller class public method - spring

Question

I need to test a public method in spring Controller class. Unfortunately my understanding of Spring is miniscule. All i know is that there are 2 repository classes that are wired to database and the method i want to test retrieves record from both databases like in the example:
#Controller
public class CalculateController {
static double ZERO = 0.00;
static double PROFIT_BOUND = 0.01;
static int DECIMAL_PLACES = 2;
static double MARGIN_PERCENT = 10;
static double PERCENT_DIVIDER = 100;
static boolean renderTable = false;
#Autowired (required = false)
private StateRepository stateRepository;
#Autowired (required = false)
private ProductRepository productRepository;
#Autowired (required = false)
private InternationalTransportCostsRepository internationalTransportCostsRepository;
// some other code unrelated to topic
public Double[] calculateProfitUSA(State state, Product product, Double finalPrice) {
Double[] tab;
if (getTax(state.getId(), product.getCategory()) == ZERO) {
tab = calculateMarginWithoutTaxUSA(state, product, finalPrice);
} else {
tab = calculateMarginWithTaxUSA(state, product, finalPrice);
}
return tab;
}
private Double[] calculateMarginWithTaxUSA(State state, Product product, Double finalPrice) {
Double[] tab = new Double[3];
double profit = calcUSA(state, product, finalPrice);
double estimatedPrice = (product.getCurrentPrice() + state.getTransportCost());
estimatedPrice = estimatedPrice + (estimatedPrice * (getTax(state.getId(), product.getCategory()) / PERCENT_DIVIDER));
double margin = estimatedPrice * MARGIN_PERCENT / PERCENT_DIVIDER;
estimatedPrice = estimatedPrice + (estimatedPrice * MARGIN_PERCENT / PERCENT_DIVIDER);
double currentProfit = calcUSA(state, product, estimatedPrice);
while (currentProfit < margin) {
estimatedPrice += PROFIT_BOUND;
currentProfit = calcUSA(state, product, estimatedPrice);
}
tab[0] = Precision.round(profit, DECIMAL_PLACES);
tab[1] = Precision.round(estimatedPrice, DECIMAL_PLACES);
tab[2] = Precision.round(margin, DECIMAL_PLACES);
return tab;
}
public Double getTax(Long id, String categoryName) {
if (categoryName.equals("Groceries")) {
return stateRepository.findById(id).get().getGroceriesTax();
} else if (categoryName.equals("Prepared-food")) {
return stateRepository.findById(id).get().getPreparedFoodTax();
} else if (categoryName.equals("Prescription-drug")) {
return stateRepository.findById(id).get().getPrescriptionDrugTax();
} else if (categoryName.equals("Non-prescription-drug")) {
return stateRepository.findById(id).get().getNonPrescriptionDrugTax();
} else if (categoryName.equals("Clothing")) {
return stateRepository.findById(id).get().getClothingTax();
} else if (categoryName.equals("Intangibles")) {
return stateRepository.findById(id).get().getIntangiblesTax();
}
return null;
}
I have been trying to search a solution on google for 2 days, I failed. All i managed to come up with is this:
#WebMvcTest(CalculateController.class)
public class CalculateAlgorithmsTests {
#InjectMocks
private CalculateController calc;
#Mock
private StateRepository stateRepository;
#Mock
private ProductRepository productRepository;
private List<State> states;
private List<Product> products;
#Test
public void calculateProfitUSATest(){
states = CSVReader.readStatesFromCSV("csvFiles/states.csv");
products = CSVReader.readProductsFromCSV("csvFiles/products.csv");
productRepository.saveAll(CSVReader.readProductsFromCSV("csvFiles/products.csv"));
stateRepository.saveAll(CSVReader.readStatesFromCSV("csvFiles/states.csv"));
State Connecticut = states.get(5);
Product Apple = products.get(0);
double [] expected = {25,12,32};
Assertions.assertEquals(expected,calc.calculateProfitUSA(Connecticut,Apple,30.23));
}
}
And I get this response from console:
java.util.NoSuchElementException: No value present
at java.base/java.util.Optional.get(Optional.java:141)
at com.taxcalc.controllers.CalculateController.getTax(CalculateController.java:215)
at com.taxcalc.controllers.CalculateController.calculateProfitUSA(CalculateController.java:167)
at com.taxcalc.CalculateAlgorithmsTests.calculateProfitUSATest(CalculateAlgorithmsTests.java:41)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:675)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:117)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$7(TestMethodTestDescriptor.java:184)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:180)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:127)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:68)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1507)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1507)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:229)
at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:197)
at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:211)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:191)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:69)
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

Answer 1

It looks like there is no result for your given id when calling stateRepository.findById(id).
You should mock that in your test by using sth like
State someState = new State()
Mockito.when(stateRepository.findById(someId)).thenReturn(Optional.of(someState))
You need to make sure that someId has the same value as the State you are calling the public method with.
The calls of stateRepository.saveAll() could then be omitted because you would explicitly mock the behaviour rather than using the given data from the CSV.
This is just a suggestion.
Another suggestion is to move this kind of logic into a service. Controllers usually define the HTTP related behaviour rather than haven business logic.