Stress Test Concurrency Jpa Entity Random Update
A runnable example in Java to create a cucumber test code files to simulate multiple read and write entity via JPA repository
Sure, here’s an example of a Cucumber test for a JPA repository that simulates multiple read and write operations on an entity:
@RunWith(Cucumber.class)
public class MyEntityRepositorySteps {
@Autowired
private MyEntityRepository repository;
private MyEntity entity;
private List<MyEntity> entities;
@Given("an existing entity")
public void an_existing_entity() {
entity = new MyEntity();
entity.setSomeField("value");
repository.save(entity);
}
@When("I retrieve the entity by ID")
public void i_retrieve_the_entity_by_id() {
entity = repository.findById(entity.getId()).orElse(null);
}
@When("I update the entity")
public void i_update_the_entity() {
entity.setSomeField("new value");
repository.save(entity);
}
@When("I retrieve all entities")
public void i_retrieve_all_entities() {
entities = repository.findAll();
}
@When("I delete the entity")
public void i_delete_the_entity() {
repository.delete(entity);
}
@Then("the entity is updated")
public void the_entity_is_updated() {
MyEntity updatedEntity = repository.findById(entity.getId()).orElse(null);
assertThat(updatedEntity.getSomeField()).isEqualTo("new value");
}
@Then("all entities are retrieved")
public void all_entities_are_retrieved() {
assertThat(entities).hasSizeGreaterThan(0);
}
@Then("the entity is deleted")
public void the_entity_is_deleted() {
MyEntity deletedEntity = repository.findById(entity.getId()).orElse(null);
assertThat(deletedEntity).isNull();
}
}
In this example, we have a JPA repository MyEntityRepository that manages MyEntity entities. The test simulates multiple read and write operations on the repository by using Cucumber’s Given-When-Then syntax.
In the Given step, we create and save an entity to the repository. In the When steps, we retrieve, update, retrieve all, and delete the entity using the repository methods. In the Then steps, we assert that the expected changes have been made to the entity and/or the repository.
Note that this is just a simple example to illustrate the basic structure of a Cucumber test for a JPA repository. In a real-world application, you may need to include more complex scenarios, multiple entities, and additional assertions to thoroughly test the repository behavior.
Sample code to implement this with cucumber feature
Here is example of a Cucumber feature file for the JPA repository test scenario I described in my previous answer:
Feature: JPA Repository CRUD operations
Scenario: Update and delete an existing entity
Given an existing entity
When I retrieve the entity by ID
And I update the entity
And I delete the entity
Then the entity is deleted
Scenario: Retrieve all entities
Given an existing entity
When I retrieve all entities
Then all entities are retrieved
In this feature file, we have two scenarios: “Update and delete an existing entity” and “Retrieve all entities”. Both scenarios use the Given-When-Then syntax to describe the steps of the test.
The first scenario simulates updating and deleting an existing entity using the JPA repository. The second scenario simulates retrieving all entities from the repository.
You can use the Cucumber test code I provided in my previous answer to implement the step definitions for this feature file. Once you have implemented the step definitions, you can run the Cucumber test to execute the scenarios and verify that the JPA repository behaves as expected.
Use case : To simulate 100 thread to read and 2 random threads to update entity
Here’s an example of how you can simulate 100 threads to read and 2 random threads to update an entity using Cucumber and Java threads:
Feature: JPA Repository concurrent access
Scenario: Concurrent access to an entity
Given an existing entity
When I spawn 100 threads to read the entity
And I spawn 2 random threads to update the entity
Then the updates are applied to the entity
Scenario Outline: Concurrent access to multiple entities
Given <entityCount> existing entities
When I spawn 100 threads to read the entities
And I spawn 2 random threads to update the entities
Then the updates are applied to the entities
Examples:
| entityCount |
| 10 |
| 50 |
| 100 |
In the first scenario, we simulate 100 threads to read the entity and 2 random threads to update the entity. In the second scenario, we simulate concurrent access to multiple entities, with the number of entities specified as a parameter in the Examples table.
To implement the step definitions for these scenarios, you can use Java threads to spawn the read and write operations concurrently. Here’s an example of how you can implement the step definitions for the first scenario:
public class JpaConcurrencySteps {
@Autowired
private MyEntityRepository repository;
private MyEntity entity;
@Given("an existing entity")
public void an_existing_entity() {
entity = new MyEntity();
entity.setSomeField("value");
repository.save(entity);
}
@When("I spawn {int} threads to read the entity")
public void i_spawn_threads_to_read_the_entity(int threadCount) throws InterruptedException, ExecutionException {
ExecutorService executor = Executors.newFixedThreadPool(threadCount);
List<Future<MyEntity>> futures = new ArrayList<>();
for (int i = 0; i < threadCount; i++) {
Future<MyEntity> future = executor.submit(() -> repository.findById(entity.getId()).orElse(null));
futures.add(future);
}
List<MyEntity> entities = futures.stream().map(future -> {
try {
return future.get();
} catch (InterruptedException | ExecutionException e) {
return null;
}
}).collect(Collectors.toList());
executor.shutdown();
executor.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS);
assertThat(entities).hasSize(threadCount);
}
@When("I spawn 2 random threads to update the entity")
public void i_spawn_random_threads_to_update_the_entity() throws InterruptedException {
Random rand = new Random();
Thread thread1 = new Thread(() -> {
entity.setSomeField("value 1");
repository.save(entity);
});
Thread thread2 = new Thread(() -> {
entity.setSomeField("value 2");
repository.save(entity);
});
if (rand.nextBoolean()) {
thread1.start();
thread2.start();
} else {
thread2.start();
thread1.start();
}
thread1.join();
thread2.join();
}
@Then("the updates are applied to the entity")
public void the_updates_are_applied_to_the_entity() {
MyEntity updatedEntity = repository.findById(entity.getId()).orElse(null);
assertThat(updatedEntity.getSomeField()).isIn("value 1", "value 2");
}
}
In this example, we use the ExecutorService and Future classes to spawn multiple threads to read the entity concurrently. We also use the Thread class to spawn two random threads to update the entity concurrently. Finally, we assert that the updates are applied to the entity after
