Managing Test Data

Have you ever tried to troubleshoot an issue taking a looking at the log files? I bet you did! And it turns out the issue is related to data usage because, you know, users will use real data! Developers won't! A good thing about your recent troubleshooting is that you can understand the data. It's not a bunch of numbers or UUIDs in the name field. How about your development environment? Probably you use either hard-coded data or random strings.

This talk will show you how to manage testing data in two different ways.
The first way is the creation of a Test Data Factory approach, where we will use the Factory Pattern to easily create any objects we want with understandable and reliable data. This approach will make you in control of your own data, so you can find any bug in the early stages of the SDLC and the DataFaker library will help us to generate good random data in every execution.

In a second way, we will apply the Data-Driven Testing approach, where the same requirement can be applied to different sets of data, generating different results. This approach can reduce the amount of code and the execution time. With the support of JUnit 5 you will learn how to do it in different ways: value source, internal method source, external method source, argument provider, and CVS source.

You will learn how to write Data-Driven tests using JUnit 5 in a SpringBoot application in the integration layer, using the Test Data Factory approach to create necessary and reliable data.

Transcript

1. MANAGING TEST DATA @eliasnogueira
2. ELIAS NOGUEIRA Senior Principal Software Engineer Brazil Oracle Ace Java Magazine NL Editor Java Champion
3. THE PROBLEM WE WANT TO SOLVE
4. hard troubleshooting data without meaning is hard to understand [INFO ] 2023-03-05 18:03:54.081 [main] Person - model1 - Person[ name=etSfgOGRQA, surname=USwRiZSZnKdYAlYBNYJVcDFRgmSLfO, email=aHrCbpKHJz@gmail.com, age=1, address=XmcWoqivEzSoUwEksGNjlzrjUmWKKCIDOTsDnPAlHPQMJaWYzt] [INFO ] 2023-03-05 18:03:54.090 [main] Person - model1 - Person[ name=rtxhUtqzhV, surname=yruPCovuOMXrXUKqZnkxgrDIsdUWMY, email=bUIXMOawHw@gmail.com, age=60, address=tFlnvWupyHnnHkAzuHAFzmRbrFUjwViqHSUEDjqCWfQdjKhBFM]
5. hard troubleshooting data without meaning is hard to understand [INFO ] 2023-03-05 18:03:54.081 [main] Person - model1 - Person[ name=etSfgOGRQA, surname=USwRiZSZnKdYAlYBNYJVcDFRgmSLfO, email=aHrCbpKHJz@gmail.com, age=1, address=XmcWoqivEzSoUwEksGNjlzrjUmWKKCIDOTsDnPAlHPQMJaWYzt]
6. not prioritized data requirements data must match any rule or restriction [INFO ] 2023-03-05 18:03:54.081 [main] Person - model1 - Person[ name=etSfgOGRQA, surname=USwRiZSZnKdYAlYBNYJVcDFRgmSLfO, email=aHrCbpKHJz@gmail.com, age=1, address=XmcWoqivEzSoUwEksGNjlzrjUmWKKCIDOTsDnPAlHPQMJaWYzt] probably will make a test fail
7. no patterns for data generation we must avoid code duplication private static Person personToCreate() { Person person = new Person( "Test user", "Surname", "test.user123@gmail.com", 18, "User address, 50 – Brühl" ); return person; } multiple methods to generate the same data can (wrongly) exist
8. hard troubleshooting not prioritized data requirements no patterns for data generation - possibly fixed/data repetition
9. HOW TO SOLVE THE PROBLEM?
10. define a way to generate data use a specialized tool understand the data requirements know the testing library support for data 1⃣ 2⃣ 3⃣ 4⃣
11. DEFINE A WAY TO GENERATE DATA
12. There are some approaches to generating data - Combining Object Mother and Fluent Builder for the Ultimate Test Data Factory - Test Data Builders and Object Mother: another look - Writing Clean Tests – New Considered Harmful - Test Data Builders: an alternative to the Object Mother pattern define a way to generate data
13. common approaches builder pattern, in the Model objects factory pattern to generate the data tool for dynamic data generation test data factory
14. model object @Data @Builder @EqualsAndHashCode public class Simulation { @JsonIgnore private Long id; private String name; private String cpf; private String email; private BigDecimal amount; private Integer installments; private Boolean insurance; }
15. builder pattern var simulation = Simulation.builder() .cpf("94827495037") .name("John Doe") .email("john@gmail.com") .amount(new BigDecimal("1000")) .installments(5) .insurance(true) .build();
16. factory pattern public final class SimulationDataFactory { public static Simulation createSimulation() { return Simulation.builder().cpf("94827495037") .name("John Doe").email("john@gmail.com") .amount(new BigDecimal("1000")).installments(5) .insurance(true).build(); } }
17. Talk is cheap. Show me the code. Linus Torvalds
18. USE A SPECIALIZED TOOL
19. https://www.slideshare.net/JaapCoomans/fairies-fakers-and-factories-boost-your-tests-with-better-test-data
20. use a specialized tool Tool What it does Comment Easy Random Generate random data based on Java beans For a long time not updated (3 years) Uses JavaFaker for specialized data jFairy Generate data based on different aspects Uses Apache Commons library, IBAJ4J, and custom YAML files Instancio Creates and populates objects Uses a custom solution for data generation DataFaker Generate data based on YAML and random code Fork from JavaFaker with a more active community
21. datafaker Faker faker = new Faker(Locale.GERMAN); faker.name().fullName(); // Freiherrin Amar von Lienshöft faker.finance().iban("DE"); // DE37941528189220696520 faker.internet().emailAddress(); // emily.keller@gmx.de faker.expression("#{date.birthday ‘yy MM dd hh:mm:ss'}"); // 78 10 08 10:04:34
22. test data factory public final class SimulationDataFactory { public static Simulation createSimulation() { return Simulation.builder() .cpf("94827495037") .name("John Doe") .email(("john@gmail.com") .amount(new BigDecimal("1000")) .installments(5) .insurance(true) .build(); } } Combination of builder + factory
23. test data factory public final class SimulationDataFactory { public static Simulation createSimulation() { return Simulation.builder() .cpf(faker.cpf().valid()) .name(faker.name().fullName()) .email(faker.internet().emailAddress()) .amount(new BigDecimal(faker.number().numberBetween(1000, 40000))) .installments(faker.number().numberBetween(2, 48)) .insurance(faker.bool().bool()) .build(); } } Combination of builder + factory + tool
24. Talk is cheap. Show me the code. Linus Torvalds
25. UNDERSTAND THE DATA REQUIREMENTS
26. understand the data requirements When we have data requirements to follow… @Min(value = 1000, message = "Amount must be equal or greater than $ 1.000") @Max(value = 40000, message = "Amount must be equal or less than than $ 40.000") private BigDecimal amount; @Min(value = 2, message = "Installments must be equal or greater than 2") @Max(value = 48, message = "Installments must be equal or less than 48") private Integer installments;
27. public final class SimulationDataFactory { public static Simulation createSimulation() { return Simulation.builder() .cpf(faker.cpf().valid()) .name(faker.name().fullName()) .email(faker.internet().emailAddress()) .amount(new BigDecimal(faker.number().numberBetween(1000, 40000))) .installments(faker.number().numberBetween(2, 48)) .insurance(faker.bool().bool()).build(); } } We must generate the data based on that conditions understand the data requirements
28. Talk is cheap. Show me the code. Linus Torvalds
29. KNOW THE TESTING LIBRARY SUPPORT FOR DATA
30. JUnit 5 data driven Value Source Internal Method Source External Method Source Argument Provider CSV Provider
31. Value Source JUnit 5 data driven class JUnitValueSourceTest { private static final int VALUE = 7; @DisplayName("Values are greater than or equals to") @ParameterizedTest(name = "{0} is greater than or equals to " + VALUE) @ValueSource(ints = {7, 10, 12, 40}) void valueSourceExample(int value) { assertThat(value).isGreaterThanOrEqualTo(VALUE); } }
32. Internal Method Source JUnit 5 data driven class JUnitInternalMethodSourceTest { @DisplayName("All products should be cheap") @ParameterizedTest(name = "product ''{0}'' of amount ${1} is cheap") @MethodSource("cheapProducts") void cheapProducts(String product, BigDecimal amount) { final BigDecimal maximumPrice = new BigDecimal("30.0"); assertThat(product).isNotEmpty(); assertThat(amount).isLessThanOrEqualTo(maximumPrice); } static Stream<Arguments> cheapProducts() { return Stream.of( arguments("Micro SD Card 16Gb", new BigDecimal("6.09")), arguments("JBL GO 2", new BigDecimal("22.37")), arguments("iPad Air Case", new BigDecimal("14.99")) ); } }
33. JUnit 5 data driven class JUnitExternalMethodSourceTest { private final String CHEAP_PRODUCTS = "com.eliasnogueira.datadriven.JUnitExternalData#cheapProducts"; @ParameterizedTest(name = "product ''{0}'' of amount ${1} is cheap") @MethodSource(value = CHEAP_PRODUCTS) void cheapProducts(String product, BigDecimal amount) { // test goes here } public class JUnitExternalData { public static Stream<Arguments> cheapProducts() { return Stream.of( arguments("Micro SD Card 16Gb", new BigDecimal("6.09")), arguments("JBL GO 2", new BigDecimal("22.37")), arguments("iPad Air Case", new BigDecimal("14.99")) ); } External Method Source
34. Argument Provider JUnit 5 data driven class JUnitArgumentProviderTest { private static final String MAXIMUM_PRICE = "30.0"; @DisplayName("Products should not exceed the maximum price") @ParameterizedTest(name = "product ''{0}'' of amount ${1} does not exceeds $" + MAXIMUM_PRICE) @ArgumentsSource(ProductsDataArgumentProvider.class) void cheapProducts(String product, BigDecimal amount) { assertThat(product).isNotEmpty(); assertThat(amount).isLessThanOrEqualTo(new BigDecimal(MAXIMUM_PRICE)); } } public class ProductsDataArgumentProvider implements ArgumentsProvider { @Override public Stream<? extends Arguments> provideArguments(ExtensionContext extensionContext) { return Stream.of( arguments("Micro SD Card 16Gb", new BigDecimal("6.09")), arguments("JBL GO 2", new BigDecimal("22.37")), arguments("iPad Air Case", new BigDecimal("14.99")) ); } }
35. CSV Provider JUnit 5 data driven class JUnitCSVSourceTest { private static final String MAXIMUM_PRICE = "30.0"; @DisplayName("Products should not exceed the maximum price") @ParameterizedTest(name = "product ''{0}'' of amount ${1} does not exceeds $" + MAXIMUM_PRICE) @CsvFileSource(resources = "/products.csv", numLinesToSkip = 1) void productsLassThan(String product, BigDecimal amount) { assertThat(product).isNotEmpty(); assertThat(amount).isLessThanOrEqualTo(new BigDecimal(MAXIMUM_PRICE)); } } product,amount Micro SD Card 16Gb,6.09 JBL GO 2,22.37 iPad Air Case,14.99 products.csv
36. Talk is cheap. Show me the code. Linus Torvalds
37. REFERENCES
38. JUnit 5 data driven Main project https://github.com/eliasnogueira/manage-testing-data-java • Value Source • Internal Method Source • External Method Source • external method source data class • Argument Provider • argument provider data class • CSV Provider • csv file
39. Main project https://github.com/eliasnogueira/credit-api/tree/manage-data • TestData Factory • Argument provider for edge cases • Tests test data factory
40. THANK YOU! @eliasnogueira https://github.com/eliasnogueira/public-speaking