I'm playing around with Vaadin and Spring Boot, but at the moment I always see the following log output with every reload:
Storing non-serializable bean [com.vaadin.spring.internal.SpringViewDisplayRegistrationBean#561f1569] with name [com.vaadin.spring.internal.SpringViewDisplayRegistrationBean#0] in [UIBeanStore[id=225748b3, name=UI:0]]
I don't have any idea where to search, which class or which part of the code could cause that. Any idea where to start?
Related
This question asks for some specifics about more general topic regarding modularization of bean validation I asked before.
In question linked above, following this documentation and this post I split annotation and ConstraintValidator definition into 2 java modules, and linked them together using ServiceLoader as shown in documentation here. Works, mostly. But there is one unsolved issue, that it does not work for validation defined via XML, which I did according to documentation again. What does not work: The pairing between annotation and ConstraintValidator is not set, the service loader stuff is not used at all.
To recap: I have working setup using this ServiceLoader approach and it works when validating stuff coming through rest layer. All paired correctly.
BUT! We are getting these DTOs also through kafka. And here we have two different flows. There is some initialization of common ConstraintValidators on startup, and then:
if we first get REST message, ServiceLoader stuff is discovered only at this request time, some next initialization is done seemignly, and after that even kafka messages works, meaning pairing for custom validator is available everywhere. (Great!)
if kafka message arrives first though(typical), no service loader stuff is consulted and somehow it 'destroys' the configuration in way, that even if later rest request comes it won't work either, saying, that there is no ConstraintValidator for given annotation. The initialization is completed somehow defectively.
validation.xml is as easy as:
<validation-config
xmlns="http://xmlns.jcp.org/xml/ns/validation/configuration"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/validation/configuration validation-configuration-2.0.xsd"
version="2.0">
<constraint-mapping>/META-INF/validation-constraints.xml</constraint-mapping>
</validation-config>
notes:
2.0 version is because of hibernate-validator 6.2.0 which comes from spring dependency management.
Why not use annotation and dump this xml stuff altogether? Not mine file, unmodifiable.
If there is some trivial newbie mistake, please advise. Maybe there is some way how to kick in service loader functionality into action in validation.xml file, I'm not aware of and cannot find anywhere.
EDITS/suggestions:
A: try to inject validator on startup to make sure it's loaded:
#Autowired
private Validator validator;
#EventListener(ApplicationReadyEvent.class)
public void logReady() {
System.out.println(validator.toString());
}
did print initialized validator, did not help though.
Project structure:
Here is the repository (no class exceeds 20 lines of code): https://github.com/MoskovchenkoD/spring5-jokes
Here is the problem: Service implementation isn't used, and 'joke' attribute doesn't get printed on the page (just '123'). Controller's #RequestMapping method is simply ignored or bypassed.
How to fix it? I was following a step-by-step video from generating a project at start.spring.io to launching it.
Much appreciated!
Yet another childish error =(
I moved the Application class one level up and now it works fine.
In a Spring Boot application how do you register custom converts to be used when processing application configuration?
I have made a custom convert (org.springframework.core.convert.converter.Converter) so it can be used by the ApplicationConversionService/Binder to parse #ConfiguraitonProperties defined in application.properties and application.yaml configuration files but do not know how to register it.
I have tried the solution here https://stackoverflow.com/a/41205653/45708 but it creates an instance of my converter after the application configuration parameters have been processed.
I ran into this issue myself recently. From what I can tell, the key issue is that binding to configuration properties occurs very early in the Spring startup process, before the Application Context is fully initialized. Therefore the usual methods for registering a converter are not reliable. In fact the ConversionService used for configuration binding appear to be a one-off and not really connected to the ConversionService that is stored in the Application Context.
I was able to get something working but it feels like a hack, as it relies on internal implementation details that may work today but not tomorrow. In any case, this is the code I used:
((ApplicationConversionService) ApplicationConversionService.getSharedInstance()).addConverter(myCustomConverter);
The trick I found was to make sure this gets called as soon as possible at application startup so that it gets called before the configuration binding where it's needed. I put it in a #PostConstruct block inside my main #SpringBootApplication class as this seemed to get invoked early on, at least in my case.
I am having circular dependency in my application. I did not get any circular dependency issue while server startup on my local setup or other 3 setups I was working on.
But, I was getting circular dependency error on server startup on production environment.
Below was the error :
Error creating bean with name 'someBean': Bean with name 'someBean' has been injected into other beans [someOtherBean] in its raw version as part of a circular reference, but has eventually been wrapped. This means that said other beans do not use the final version of the bean. This is often the result of over-eager type matching - consider using 'getBeanNamesOfType' with the 'allowEagerInit' flag turned off, for example.
when I added default-lazy-init = "true" in my application_context.xml file, error got resolved.
My question is, how come I wasn't getting any such error on my local or other setup even though I wasn't having default-lazy-init = "true" in my application_context.xml file. I came to know that the problem can be solved in several ways. But I would like to know the root cause of how spring differs in bean creation from one system to another. Or is it specific to OS or Tomcat server.
I am trying to implement a function where a admin user can terminate another user's session. I followed the official Spring Security documentation here: http://docs.spring.io/spring-security/site/docs/current/reference/htmlsingle/#list-authenticated-principals and started with getting all currently logged in users through sessionRegistry.getAllPrincipals(), but it always returned an empty list.
I set a breakpoint in SessionRegistryImpl.registerNewSession() and could see it did indeed get invoked and it did add the UserDetails (my own implementation with both equals() and hashCode() implemented) to the hashmap principals. But when I access sessionRegistry bean from a Spring MVC controller, the list is always empty.
My configuration looks pretty much the same as the documentation.
How to fix this? Did anyone successfully get SessionRegistry to work with Spring Security 4? I remember I made it work with Spring Security 3 by following these intructions(enter link description here)
OK, so I fixed the issue by cleaning up the Spring configuration files, as suggested by the comments. Someone messed up with the web.xml - he added a reference to the context XML that is already referenced by the Spring's DispatcherServlet, causing it to be loaded twice. He didn't know it, because Spring references the file implicitly.
P.S.
I learned my lessons, but 2 things the Spring folks could do better (maybe in Spring 5?):
There shouldn't be implicit context file loading. Currently, the framework will try to load the application context from a file named [servlet-name]-servlet.xml located in the application's WebContent/WEB-INF directory. Convention over configuration fails in this case.
There should be warning when a bean is loaded twice, if someone need to override a bean definition, he must declare explicitly. Otherwise it would take a lot of time to debug the kind of error this mistake will cause.