I have seen many great workarounds to create Flyway JavaMigrations and injecting Spring Beans using #DependsOn and ApplicationContextAware (e.g. https://stackoverflow.com/a/48242865/5244937).
However a part of the Flyway 6 documentation claims Dependency Injection would be possible natively for Spring Beans:
https://flywaydb.org/documentation/api/hooks#java-based-migrations-as-spring-beans
https://github.com/flyway/flyway/issues/1062
Is is true? How would this work?
Mark your migrations as #Component and put them in a folder that is scanned by spring (e.g. within your application package and not in db.migrations). This will ensure #Autowired can be used because the bean is instantiated by spring. (The migrations in db.migrations will be scanned by flyway automatically and are not instantiated by spring.)
Then implement a FlywayConfigurationCustomizer to add the migrations by loading them from the spring context:
#Configuration
class FlywayConfiguration implements FlywayConfigurationCustomizer {
#Autowired
private ApplicationContext applicationContext;
#Override
public void customize(FluentConfiguration configuration) {
JavaMigration[] migrationBeans = applicationContext
.getBeansOfType(JavaMigration.class)
.values().toArray(new JavaMigration[0]);
configuration.javaMigrations(migrationBeans);
}
}
Related
I asked a question more specific to my case about 2 hours ago, but I realised I'm not really addressing my problem at the root cause.
I have a Spring application that uses Spring Security. Throughout my application, (Controllers, service classes etc) I'm using dependency injection and it all works fine. However, I recently started configuring Spring Security, and I can't inject any dependencies inside the classes in my "security" package. Online I read somewhere: "Also when you use #Autowired in the class of which you created a new instance, the Spring context will not be known to it and thus most likely this will also fail" and I was wondering if this maybe had something to do with my issue. My spring configuration basically has one "starting-point", that is the following class:
#Component
#Service
public class AppInitializer implements WebApplicationInitializer {
#Override
public void onStartup(ServletContext sc) throws ServletException {
AnnotationConfigWebApplicationContext root = new AnnotationConfigWebApplicationContext();
root.register(SecSecurityConfig.class);
sc.addListener(new ContextLoaderListener(root));
sc.addFilter("securityFilter", new DelegatingFilterProxy("springSecurityFilterChain"))
.addMappingForUrlPatterns(null, false, "/*");
}
}
This code is run on startup. As you can see, it is registering the SecSecurityConfig.class which is where I configure Spring Security. Inside of that class and onwards (all classes it uses and all classes that those classes use) I can't inject any dependencies. I was wondering if anyone could tell me what the problem could be. Sorry if I'm unclear or incorrect - please tell me so, I find the concept of DI somewhat hard to grasp. My component-scan in XML is: <context:component-scan base-package="com.qars"/> which is the package that my security package is also in.
Also all my classes are annotated with #Component or #Service
Is ApplicationContext automatically instantiated in Spring?
If I have my bean defined like this
#Component
public class Car{
...
}
and then I have my config class which tells Spring container where to look for beans through the annotation #ComponentScan
#Configuration
#ComponentScan
public class AppConfig {
...
}
Is Spring automatically creating a context loading all my beans? Or do I have to create it programmatically? If so how do I do it, with something like this?
#Configuration
#ComponentScan
public class AppConfig {
ApplicationContext context = new AnnotationConfigApplicationContext(AppConfig.class);
context.getBean(Car.class);
...
}
Even doing this, there may be a problem, because every time I need the context I have to call new AnnotationConfigApplicationContext...
what is the recommended way to instantiate the context and making him available inside the whole project, maybe as a bean like inside Spring boot app where i can just autowire it.
How Spring Boot can initialize it, load all the beans and let the context available as a bean, ready to be autowired?
No, Application Context isn't automatically instantiated, if you're having a simple and basic Spring Core application. Moreover, your #Configuration class won't scan anything and won't create any beans, if you don't create your Spring Container/Context explicitly with that #Configuration class.
There are several ways of creating Application Context, but the most popular and traditional ones are:
ApplicationContext context = new ClassPathXmlApplicationContext(applicationContext.xml) - implying, that you have your container configuration in the applicationContext.xml file;
ApplicationContext context = new AnnotationConfigApplicationContext(ConfigClass.class); - implying, that your ConfigClass is the #Configuration class.
However, if you have the Spring Boot application annotated with #SpringBootApplication, then the Application Context will be automatically instantiated for you, because:
#SpringBootApplication annotation consists of:
#EnableAutoConfiguration - which enables Spring Boot’s auto-configuration mechanism;
#ComponentScan - which enable #Component scan on the package where the application is located;
#Configuration - allows to register extra beans in the context or import additional configuration classes.
and this will spin up the context for you.
You can obtain the reference to the Spring Context created by Spring Boot, by the factory method you have in your main method: SpringApplication.run(MainClass.class, args);
This returns the reference to the Application Context and you can assign it to variable like this:
ApplicationContext context = SpringApplication.run(MainClass.class, args)
I have some experience with spring dependency injection and transaction management but I am new to spring security. When i was reading an article related to spring security, I found that #Configuration annotation is used in an example but there were no bean definitions to be found.
According to my understanding, #Configuration annotation is used in classes which contain bean definitions. I need to know that what does the #Configuration annotation do in this example.
#Configuration
public class ApplicationSecurity extends WebSecurityConfigurerAdapter {
#Autowired
DataSource dataSource;
... // web stuff here
#Override
public configure(AuthenticationManagerBuilder builder) {
builder.jdbcAuthentication().dataSource(dataSource).withUser("dave")
.password("secret").roles("USER");
}
}
Thank you
It's not mandatory to have Bean definitions in Spring managed classes.
In this case #Configuration (which wraps #Component) is used to indicate to Spring that this class should be instantiated and all it's dependencies should be injected - in this case that's DataSource and AuthenticationManagerBuilder. This is an example of Inversion of Control principle.
Spring also provides these ConfigurerAdapter hook points, where you can tweak the default configuration of an already instantiated component.
This is exactly what is happening in your Configuration class.
I have a Spring App that uses JPA repositories (CrudRepository interfaces). When I try to test my controller using the new Spring test syntax #WebMvcTest(MyController.class), it fails coz it tries to instantiate one of my service class that uses JPA Repository, does anyone has any clues on how to fix that? The app works when I run it.
Here is the error:
***************************
APPLICATION FAILED TO START
***************************
Description:
Parameter 0 of constructor in com.myapp.service.UserServiceImpl required a bean of type 'com.myapp.repository.UserRepository' that could not be found.
Action:
Consider defining a bean of type 'com.myapp.repository.UserRepository' in your configuration.
According to the doc
Using this annotation will disable full auto-configuration and instead apply only configuration relevant to MVC tests (i.e. #Controller, #ControllerAdvice, #JsonComponent Filter, WebMvcConfigurer and HandlerMethodArgumentResolver beans but not #Component, #Service or #Repository beans).
This annotion only apply on the Spring MVC components.
If you are looking to load your full application configuration and use MockMVC, you should consider #SpringBootTest combined with #AutoConfigureMockMvc rather than this annotation.
I was able to unit test a Rest Controller by implementing junit 5 and using #SpringJUnitConfig along with #WebMvcTest. I am using Spring Boot 2.4.5 and this is my example:
#SpringJUnitConfig
#WebMvcTest(controllers = OrderController.class)
class OrderControllerTest {
#Autowired
private MockMvc mockMvc;
// This is a Mock bean of a Spring Feign client that calls an external Rest Api
#MockBean
private LoginServiceClient loginServiceClient;
// This is a Mock for a class which has several Spring Jpa repositories classes as dependencies
#MockBean
private OrderService orderService;
#DisplayName("should create an order")
#Test
void createOrder() throws Exception {
OrderEntity createdOrder = new OrderEntity("123")
when(orderService.createOrder(any(Order.class))).thenReturn(createdOrder);
mockMvc.perform(post("/api/v1/orders").contentType(MediaType.APPLICATION_JSON).content("{orderId:123}"))
.andExpect(status().isCreated())
.andExpect(content().contentType(MediaType.APPLICATION_JSON_UTF8))TODO: here it will go the correlationId
.andExpect(jsonPath("$.orderId").value("123"));
}
}
Please only use #SpringBootTest when you are implementing integration tests.
I faced this same problem. Using #SpringBootTest and #AutoConfigureMockMvc worked perfectly for me.
I have a new CDI Java EE application running on WebSphere. Now I want to use an existing module (.jar) in my CDI project, however the existing module uses Spring with Spring annotations and an Spring XML configuration file with additional bean definitions in it. Normally I would just import the Spring XML in my project, but in the CDI application this will not work.
I tried to load the Spring XML using JBoss Seam, like so:
#Produces
#SpringContext
#Configuration(locations = "classpath*:external-spring--context.xml")
ApplicationContext context;
But the context is null? I cannot realy find good examples on how to do this, help is much appreciated :)
I solved it by adding an CDI producer that will create the Spring context using the spring XML file:
public class SpringBeansFactory {
#Inject
ApplicationContext context;
#Produces
public BusinesService getBusinessService() {
return context.getBean(BusinesService.class);
}
}
class SpringContextFactory {
#Produces
public ApplicationContext getApplicationContext() {
return new ClassPathXmlApplicationContext("classpath:spring-context.xml");
}
}