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Chain of responsibility and Spring dependency injection

I implemented a validation using the chain of responsibility pattern. The request payload to validate can have different parameters. The logic is: if the payload has some parameters, validate it and continue to validate other, else throw an exception. In a level of the validation chain I need to call other services, and here comes into play the Dependency Injection.
The validation structure is like a tree, starting from top to bottom.
So, the class where I need to start the Validation
#Service
public class ServiceImpl implements Service {
private final .....;
private final Validator validator;
public ServiceImpl(
#Qualifier("lastLevelValidator") Validator validator, .....) {
this.validator = validator;
this...........=............;
}
/...../
private void validateContext(RequestContex rc) {
Validator validation = new FirstLevelValidator(validator);
validation.validate(rc);
}
}
So the Validator Interface
public interface Validator<T> {
void validate(T object);
}
The validation classes that implements Validator
#Component
public class FirstLevelValidator implements Validator<RequestContext>{
private final Validator<RequestContext> validator;
#Autowired
public FirstLevelValidator(#Qualifier("lastLevelValidator") Validator<RequestContext> validator) {
this.validator = validator;
}
#Override
public void validate(RequestContext requestContext) {
if ( requestContext.getData() == null ) {
LOGGER.error(REQUEST_ERROR_MSG);
throw new BadRequestException(REQUEST_ERROR_MSG, INVALID_CODE);
}
if (requestContex.getData() == "Some Data") {
Validator validator = new SecondLevelValidator(this.validator);
validator.validate(requestContext);
} else {/* other */ }
}
#Component
public class SecondLevelValidator implements Validator<RequestContext>{
private final Validator<RequestContext> validator;
#Autowired
public SecondLevelValidator(#Qualifier("lastLevelValidator") Validator<RequestContext> validator) {
this.validator = validator;
}
#Override
public void validate(RequestContext requestContext) {
if ( requestContext.getOption() == null ) {
LOGGER.error(REQUEST_ERROR_MSG);
throw new BadRequestException(REQUEST_ERROR_MSG, INVALID_CODE);
}
if ( requestContext.getOption() == " SOME " ) {
validator.validate(requestContext); //HERE WHERE I CALL THE Qualifier
}
}
#Component
public class LastLevelValidator implements Validator<RequestContext>{
private final ClientService1 client1;
private final ClientService2 client2;
public LastLevelValidator(ClientService1 client1, ClientService2 client2) {
this.client1 = client1;
this.client2 = client2;
}
#Override
public void validate(RequestContext requestContext) {
Integer userId = client2.getId()
List<ClientService1Response> list = client1.call(requestContext.id(), userId);
boolean isIdListValid = list
.stream()
.map(clientService1Response -> clientService1Response.getId())
.collect(Collectors.toSet()).containsAll(requestContext.getListId());
if (!isIdListValid) {
LOGGER.error(NOT_FOUND);
throw new BadRequestException(NOT_FOUND, INVALID_CODE);
} else { LOGGER.info("Context List validated"); }
}
}
In the LastLevelValidator I need to call other services to make the validation, for that I inject into each validator class (First.., Second..) the #Qualifier("lastLevelValidator") object, so when I need to instantiate the LastLevelValidation class I can call it like validator.validate(requestContext); instance of validator.validate(ClientService1, ClientService2 ) that it would force me to propagate the ClientServices objects through all the chain from the ServiceImpl class.
Is it this a good solution ?
Is there any concern I didn't evaluate?
I tried also declaring the services I need to call for the validation as static in the LastLevelValidation, in the way that I can call it like LastLevelValidation.methodvalidar(), but look like not a good practice declares static objects.
I tried to pass the objects I need propagating it for each Validation class, but seems to me that if I need another object for the validation I have to pass it through all the validation chain.

Spring custom Scope with timed refresh of beans

I am working within an environment that changes credentials every several minutes. In order for beans that implement clients who depend on these credentials to work, the beans need to be refreshed. I decided that a good approach for that would be implementing a custom scope for it.
After looking around a bit on the documentation I found that the main method for a scope to be implemented is the get method:
public class CyberArkScope implements Scope {
private Map<String, Pair<LocalDateTime, Object>> scopedObjects = new ConcurrentHashMap<>();
private Map<String, Runnable> destructionCallbacks = new ConcurrentHashMap<>();
private Integer scopeRefresh;
public CyberArkScope(Integer scopeRefresh) {
this.scopeRefresh = scopeRefresh;
}
#Override
public Object get(String name, ObjectFactory<?> objectFactory) {
if (!scopedObjects.containsKey(name) || scopedObjects.get(name).getKey()
.isBefore(LocalDateTime.now().minusMinutes(scopeRefresh))) {
scopedObjects.put(name, Pair.of(LocalDateTime.now(), objectFactory.getObject()));
}
return scopedObjects.get(name).getValue();
}
#Override
public Object remove(String name) {
destructionCallbacks.remove(name);
return scopedObjects.remove(name);
}
#Override
public void registerDestructionCallback(String name, Runnable runnable) {
destructionCallbacks.put(name, runnable);
}
#Override
public Object resolveContextualObject(String name) {
return null;
}
#Override
public String getConversationId() {
return "CyberArk";
}
}
#Configuration
#Import(CyberArkScopeConfig.class)
public class TestConfig {
#Bean
#Scope(scopeName = "CyberArk")
public String dateString(){
return LocalDateTime.now().toString();
}
}
#RestController
public class HelloWorld {
#Autowired
private String dateString;
#RequestMapping("/")
public String index() {
return dateString;
}
}
When I debug this implemetation with a simple String scope autowired in a controller I see that the get method is only called once in the startup and never again. So this means that the bean is never again refreshed. Is there something wrong in this behaviour or is that how the get method is supposed to work?

It seems you need to also define the proxyMode which injects an AOP proxy instead of a static reference to a string. Note that the bean class cant be final. This solved it:
#Configuration
#Import(CyberArkScopeConfig.class)
public class TestConfig {
#Bean
#Scope(scopeName = "CyberArk", proxyMode=ScopedProxyMode.TARGET_CLASS)
public NonFinalString dateString(){
return new NonFinalString(LocalDateTime.now());
}
}

Creating TextIndex in Micronaut with reactive mongoDB

I am using reactive mongoDB with Micronaut application
implementation("io.micronaut.mongodb:micronaut-mongo-reactive")
Trying to create a TextIndex and search Free text functionality
public class Product {
#BsonProperty("id")
private ObjectId id;
private String name;
private float price;
private String description;
}
In spring data we have #TextIndexed(weight = 2) to create a TextIndex to the collection, what is the equivalent in the Micronaut application.

I'm afraid that Micronaut Data does not yet support automatic index creation based on annotations for MongoDB. Micronaut Data now simplifies only work with SQL databases.
But you can still create the index manually using MongoClient like this:
#Singleton
public class ProductRepository {
private final MongoClient mongoClient;
public ProductRepository(MongoClient mongoClient) {
this.mongoClient = mongoClient;
}
public MongoCollection<Product> getCollection() {
return mongoClient
.getDatabase("some-database")
.getCollection("product", Product.class);
}
#PostConstruct
public void createIndex() {
final var weights = new BasicDBObject("name", 10)
.append("description", 5);
getCollection()
.createIndex(
Indexes.compoundIndex(
Indexes.text("name"),
Indexes.text("description")
),
new IndexOptions().weights(weights)
)
.subscribe(new DefaultSubscriber<>() {
#Override
public void onNext(String s) {
System.out.format("Index %s was created.%n", s);
}
#Override
public void onError(Throwable t) {
t.printStackTrace();
}
#Override
public void onComplete() {
System.out.println("Completed");
}
});
}
}
You can of course use any subscriber you want. That anonymous class extending DefaultSubscriber is used here only for demonstration purpose.
Update: You can create indexes on startup for example by using #PostConstruct. It means to add all index creation logic in a method annotated by #PostConstruct in some repository or service class annotated by #Singleton, then it will be called after repository/service singleton creation.

junit - how to mock field in real class?

I have a tricky situation. I am using MVP architecture for android but thats not important. I have a class called DoStandardLoginUsecase that basically just connects to a server with login info and gets a access token. i am trying to test it. But the problem is the context that i am passing in to it so i can initialize dagger.
public class DoStandardLoginUsecase extends BaseUseCase {
#Inject
UserDataRepository mUserDataRepo;
private StandardLoginInfo loginInfo;
public DoStandardLoginUsecase(Context context) {
/* SEE HERE I AM USING A APPLICATION CONTEXT THAT I PASS TO DAGGER
*/
((MyApplication)context).getPresenterComponent().inject(this);
}
#Override
public Observable<Login> buildUseCaseObservable() {
return mUserDataRepo.doStandardLogin(loginInfo);
}
public void setLoginInfo(StandardLoginInfo loginInfo) {
this.loginInfo = loginInfo;
}
}
and here is the test i have so far:
public class DoStandardLoginUsecaseTest {
DoStandardLoginUsecase standardLoginUsecase;
StandardLoginInfo fakeLoginInfo;
TestObserver<Login> subscriber;
MockContext context;
#Before
public void setUp() throws Exception {
//now when i create the object since its a mock context it will fail when it tries to call real things as these are stubs. So how do i test this object. how do i create an instance of this object ? I am willing to use [daggerMock][1] if that helps also.
standardLoginUsecase = New DoStandardLoginUsecase(context);
fakeLoginInfo = new StandardLoginInfo("fred#hotmail.com","Asdfgh4534");
subscriber = TestObserver.create();
}
#Test
public void buildUseCaseObservable(){
standardLoginUsecase.seLoginInfo(fakeLoginInfo);
standardLoginUsecase.buildUseCaseObservable().subscribe(subscriber);
subscriber.assertNoErrors();
subscriber.assertSubscribed();
subscriber.assertComplete();
}
}

I would do the test like this:
public class DoStandardLoginUsecaseTest {
private DoStandardLoginUsecase target;
private MyApplication contextMock;
#Before
public void beforeEach() {
contextMock = Mockito.mock(MyApplication.class);
// Note that you need to mock the getPresenterComponent
// but I don't know what it returns.
target = new DoStandardLoginUsecase(contextMock);
}
#Test
public void buildUseCaseObservable() {
UserDataRepository userDataMock = Mockito.mock(UserDataRepository.class);
StandardLoginInfo loginInfoMock = Mockito.mock(StandardLoginInfo.class);
target.mUserDataRepo = userDataMock;
target.setLoginInfo(loginInfoMock);
Observable<Login> expected = // create your expected test data however you like...
Mockito.when(userDataMock.doStandardLogin(loginInfoMock)).thenReturn(expected);
Observable<Login> actual = target.buildUseCaseObservable();
Assert.areSame(actual, expected);
}
}

Jersey Test #Autowired field in tested class is null

I have a little problem. I think this is typical question. However, I can't find good example. My application is using Jersey. And I want to test controller by client as test. Controller has private field - StudentService. When I debug test I see, that field is null. This leads to error. And I need to inject this field. I tried this:
My Controller
#Path("/student")
#Component
public class StudentResourse {
#Autowired
private StrudentService service; // this field Spring does not set
#Path("/getStudent/{id}")
#GET
#Produces({ MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON })
public Student getStudent(#PathParam("id") long id) {
return service.get(id);
}
}
My JUnit test class:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = "classpath:config.xml")
#TestExecutionListeners({ DbUnitTestExecutionListener.class,
DependencyInjectionTestExecutionListener.class,
DirtiesContextTestExecutionListener.class,
TransactionalTestExecutionListener.class })
public class StudentResourseTest extends JerseyTest {
private static final String PACKAGE_NAME = "com.example.servlet";
private static final String FILE_DATASET = "/data.xml";
#Autowired
private StudentService service; // this field is setted by Spring, but I do not need this field for test
public StudentResourseTest() {
super(new WebAppDescriptor.Builder(PACKAGE_NAME).build());
}
#Override
protected TestContainerFactory getTestContainerFactory() {
return new HTTPContainerFactory();
}
#Override
protected AppDescriptor configure() {
return new WebAppDescriptor.Builder("restful.server.resource")
.contextParam("contextConfigLocation",
"classpath:/config.xml").contextPath("/")
.servletClass(SpringServlet.class)
.contextListenerClass(ContextLoaderListener.class)
.requestListenerClass(RequestContextListener.class).build();
}
#Test
#DatabaseSetup(FILE_DATASET)
public void test() throws UnsupportedEncodingException {
ClientResponse response = resource().path("student").path("getStudent")
.path("100500").accept(MediaType.APPLICATION_XML)
.get(ClientResponse.class);
Student student = (Student) response.getEntity(Student.class);
} }
I guees, that problem is in test class. Because, when I run my application not in test, I can directly request students and everything working fine. But when I test classes, internal field of Controller does not setted. How to fix this bug? Thanks for your answers.
This is in my config.xml
<context:component-scan base-package="com.example" />
<bean id="StudentResourse" class="com.example.servlet.StudentResourse">
<property name="service" ref="studentService" />
</bean>
<bean id="service" class="com.example.service.StudentServiceImpl" />

One issue may be that you're trying to configure your test application in constructor and in configure() method. Use one or another but not both because in this case your configure() method is not invoked and hence you may not be using SpringServlet and everything that is defined in this method.

Reference: https://github.com/jiunjiunma/spring-jersey-test and http://geek.riffpie.com/unit-testing-restful-jersey-services-glued-together-with-spring/
Idea is to get a hold of the application context inside jersey by using ApplicationContextAware interface. There after we can grab the exact bean already created by spring, in your case, StudentService. Below example shows a mocked version of the dependency, SampleService, used to test the resource layer apis.
Resource class delegating the processing to a service layer
#Component
#Path("/sample")
public class SampleResource {
#Autowired
private SampleService sampleService;
#GET
#Produces(MediaType.APPLICATION_JSON)
#Path ("/{id}")
public Sample getSample(#PathParam("id") int id) {
Sample sample = sampleService.getSample(id);
if (sample == null) {
throw new WebApplicationException(Response.Status.NOT_FOUND);
}
return sample;
}
}
Service layer encapsulating business logic
#Service
public class SampleService {
private static final Map<Integer, Sample> samples = new HashMap<>();
static {
samples.put(1, new Sample(1, "sample1"));
samples.put(2, new Sample(2, "sample2"));
}
public Sample getSample(int id) {
return samples.get(id);
}
}
Unit test for the above resource
public class SampleResourceTest extends SpringContextAwareJerseyTest {
private SampleService mockSampleService;
// create mock object for our test
#Bean
static public SampleService sampleService() {
return Mockito.mock(SampleService.class);
}
/**
* Create our own resource here so only the test resource is loaded. If
* we use #ComponentScan, the whole package will be scanned and more
* resources may be loaded (which is usually NOT what we want in a test).
*/
#Bean
static public SampleResource sampleResource() {
return new SampleResource();
}
// get the mock objects from the internal servlet context, because
// the app context may get recreated for each test so we have to set
// it before each run
#Before
public void setupMocks() {
mockSampleService = getContext().getBean(SampleService.class);
}
#Test
public void testMock() {
Assert.assertNotNull(mockSampleService);
}
#Test
public void testGetSample() {
// see how the mock object hijack the sample service, now id 3 is valid
Sample sample3 = new Sample(3, "sample3");
Mockito.when(mockSampleService.getSample(3)).thenReturn(sample3);
expect().statusCode(200).get(SERVLET_PATH + "/sample/3");
String jsonStr = get(SERVLET_PATH + "/sample/3").asString();
Assert.assertNotNull(jsonStr);
}
}
SpringContextAwareJerseyTest
#Configuration
public class SpringContextAwareJerseyTest extends JerseyTest {
protected static String SERVLET_PATH = "/api";
final private static ThreadLocal<ApplicationContext> context =
new ThreadLocal<>();
protected String getResourceLocation() {
return "example.rest";
}
protected String getContextConfigLocation() {
return getClass().getName();
}
static private String getContextHolderConfigLocation() {
return SpringContextAwareJerseyTest.class.getName();
}
protected WebAppDescriptor configure() {
String contextConfigLocation = getContextConfigLocation() + " " +
getContextHolderConfigLocation();
Map<String, String> initParams = new HashMap<>();
initParams.put("com.sun.jersey.config.property.packages",
getResourceLocation());
initParams.put("com.sun.jersey.api.json.POJOMappingFeature", "true");
return new WebAppDescriptor.Builder(initParams)
.servletClass(SpringServlet.class)
.contextParam(
"contextClass",
"org.springframework.web.context.support.AnnotationConfigWebApplicationContext")
.contextParam("contextConfigLocation", contextConfigLocation)
.servletPath(SERVLET_PATH) // if not specified, it set to root resource
.contextListenerClass(ContextLoaderListener.class)
.requestListenerClass(RequestContextListener.class)
.build();
}
protected final ApplicationContext getContext() {
return context.get();
}
#Bean
public static ContextHolder contextHolder() {
return new ContextHolder();
}
private static class ContextHolder implements ApplicationContextAware {
#Override
public void setApplicationContext(ApplicationContext applicationContext)
throws BeansException {
context.set(applicationContext);
}
}
}
Using the above with jersey 1.8