Autowire FeignClient across maven Project - spring

I have Projects built with Spring-boot, Maven and Kotlin.
I want to expose some Services and FeignClients in a maven Project, so others can use them.
For a class with Annotations like #Service that works well. But I need to expose also FeignClients, which are annotated with #FeignClient, but as it looks other Projects are not
able to inject those Clients. Do I have to configure something in my pom.xml?
Im using spring-cloud-starter-openfeign
Here is some Code.
My FeignClient looks like:
...
#FeignClient(name = "MyAPIClient", url = "\${url}", configuration = [MyApiClientConfiguration::class])
interface MyAPIClient {
...
And I try to inject that Client in another Project like this:
...
#Service
class MyService(val myAPIClient: MyAPIClient) {
...
The Error is pretty clear. It says, there is no bean with the name MyAPIClient. So it's not
visible or available. "Consider defining a bean of type 'com.mycomp.MyAPIClient' in your configuration."
Do I have to configure something explicitly to expose an OpenFeignClient to other projects in my pom.xml?
Thanks for your help

It would work automatically if you had the same package structure in both projects. See how the search for feign clients is performed by default.
In other cases, you need to specify basePackages of basePackageClasses attributes of #EnableFeignClients annotation (in the app where you need to inject your feign client). Note that if you do that, then the default behavior (scanning the current package where this annotation is placed) stops working, so you need to specify it manually too in this case.

Related

Springboot build not working because of test configuration

I have started a spring boot project using start.spring.io.
But I am getting this error-
I have read various articles on the internet about this issue and they all say about putting my tests in the same package as my Main class.
But I already have the same.
Could you point out what is wrong with my configuration?
The exception is pretty clear: You are missing a configuration for your spring context. What you need to do is to add the configuration classes for your context like so:
#SpringBootTest(classes = { TestConfiguration.class })
whereas your TestConfiguration class must be annotated with
#Configuration
and/or
#EnableAutoConfiguration
There you can add configurations to your liking. You can of course also use your DatabaseApplication class as Configuration although Im wouldn't recommend that.
The search algorithm works up from the package that contains the test until it finds a #SpringBootApplication or #SpringBootConfiguration annotated class. As long as you’ve structure your code in a sensible way your main configuration is usually found.
Make Sure your DatabaseApplication class is annotated with #SpringBootApplication .

Spring AOP aspect doesn't get applied if included from an external jar with different package name

I have a spring boot rest service that included an external project in pom as it's dependency. That external project is basically a jar that has spring AOP code.
The base package in my main application that includes this external jar with spring AOP code is x.y.z
The class in external jar where the #before advice is, is under the package a.b.c
With this class under a.b.c package, it doesn't get recognized by the main application where I want to use the spring aop implementation and apply the aspect. However, when I change it's package from a.b.c to x.y.z (which I really can't do in real life) it works fine.
I know that in spring boot service which happens to be the including service, it scans everything under root package given in the application class, x.y.z in this case and that is why aspect works fine if it's class is under x.y.z.
however, the problem is that this spring app jar will be used across multiple applications. So changing package name like this is not an option.
Is there a way to accomplish this without changing the package name of the class where spring app code is ?
Probably component scan is only activated for your application class packages by default. You can extend it to multiple packages, including the aspect package:
XML style configuration:
<context:component-scan base-package="x.y.z, a.b.c" />
Annotation style configuration:
#ComponentScan(basePackages = {"x.y.z", "a.b.c"})
Disclaimer: I am not a Spring user, only an AspectJ expert. I just knew that you can configure component scan, googled the syntax for you and hope it is correct.
Please define the bean (of jar project )inside main application. Give the #ComponentScan(basePackages = {"x.y.z", "a.b.c"}) as well as #EnableAspectJAutoProxy. Also include below piece of code.
ex:
` #Bean
public LoggingHandler loggingHandler()
{
return new LoggingHandler();
}`
Also annotate external jar code with:
`#Aspect
#Component
public class LoggingHandler {`
What #kriegaex suggests is correct. In addition to that, please make sure you are using #Component along with #Aspect. Since #Aspect is not a Spring annotation, Spring won't recognize it and hence your aspect won't be registered. So, using #Component is mandatory to getting aspects to work in Spring environment.

Can I start with a spring boot application without the annotations componentscan,autoconfiguration,configuration,springbootapplication?

I have written some code in order test integration with mongoDB. Please find the link to the main method for running this spring boot application below,
https://github.com/siva54/simpleusercontrol/blob/master/src/main/java/com/siva/UserManagementApplication.java
From what I have read, An application should contain any of the configurations from the following URL to declare how the applications manages the context,
http://docs.spring.io/autorepo/docs/spring-boot/current/reference/html/using-boot-using-springbootapplication-annotation.html
I haven't used any of those contexts, However my application works fine and I'm able to run it without any issues. Am I missing something here? Can you please help with the info of how my application is able to start and manage the context/dependencies automatically?
Thanks in advance
#SpringBootApplication is equivalent of #Configuration, #EnableAutoConfiguration and #ComponentScan. Let's consider why your application works without of any of this three annotations.
Why it works without #Configuration:
When Spring will scan packages, it will find all classes marked by #Configuration and will use them as part of configuration. But in next line you manually passed UserManagementApplication as configuration source:
SpringApplication.run(UserManagementApplication.class, args);
So spring doesn't need to find this class by scan. Therefor it is not necessary to mark it by #Configuration.
Why it works without #ComponentScan:
Class UserManagementApplication has #ImportResource("classpath:spring/application-context.xml") annotation. That means file spring/application-context.xml will be included into configuration. And this file contains next line:
<context:component-scan base-package="com.siva.*" />
So, you don't need use annotation for scan packages, because you already declared it in the xml file.
Why it works without #EnableAutoConfiguration:
This annotation allows to Spring to try guess and configure the components automatically. For example, if you include the following dependency in your build.gradle:
dependencies {
compile 'org.springframework.boot:spring-boot-starter-data-mongodb'
}
Spring configures all the components required to work with MongoDB automatically. And all you need just specify host and user/pass in the aplication.proprties file.
But you preferred to declare all needed beans manually in the spring/application-context.xml file. So, you simply don't need #EnableAutoConfiguration annotation at all.

Explicitly declaring service gateway in Java configuration

I have an application using Spring Integration where I have multiple handlers (strategies) for some service gateway methods, and I want the deployment launcher to be able to select which specific handlers are loaded. Since component scanning will pick up all of the handlers indiscriminately, I prefer to explicitly declare JavaConfig #Beans for them.
This works fine for the service objects themselves, but I can't find a way to load the service interface itself in Java without #IntegrationComponentScan. My current workaround is to include a "one-liner" XML file with an <int-gateway> tag and #ImportResource it, but I'd really prefer a more direct solution.
Is there any straightforward way in JavaConfig to tell Spring Integration to create a proxy service interface for a specific class?
GatewayProxyFactoryBean is for you.
This class is used to populate bean definition from <int:gateway> tag and from MessagingGateway annotation.
So, you can do like this:
#Bean
public GatewayProxyFactoryBean myGateway() {
GatewayProxyFactoryBean factoryBean = new GatewayProxyFactoryBean(YourServiceInterface.class);
factoryBean.setDefaultRequestChannel(gatewayRequestChannel());
return factoryBean;
}

Spring-data-mongo: MongoRepository not being wired unless I add #Component annotation

I am having a little weird behavior with my spring-data-mongo where my repository package is not being scanned by the <mongo:repositories/> tag. I am using spring 3.2.3.RELEASE with spring-data-mongo 1.2.1.RELEASE.
I have a project called edowmis and in it there are 2 maven modules, datalayer and web which a webapp.I am using the datalayer in isolation so the other module can be ignored. I have an application context for datalayer
So I wanted to test my setup by writing a small Unit/Integration test but I've noticed I can't autowire my UserRepository because It says there isn't such a bean
Since I am using IntelliJ I can see certain visuals when things are ok and not ok. I've addec <context:component-scan/> to my application context but no result.
But when I add the #Component annotation it has started identifying the Class.
all information you might need is on pastie.org
Is the #component or #Repository really necessary or something is wrong with my configuration?
Yes, the #Component or #Repository is necessary. The scan simply indicates that spring should look for classes identified via annotations (#Component, #Repository, #Service) and load them as beans. If you don't use repository or component scan, you would have to manually instantiate all spring-managed beans via XML configuration or Java configuration.
You have to tell spring which classes to turn into beans as it doesn't assume everything in the classpath is supposed to be a spring-managed bean, which is why you need to use the annotations.

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