Develop Reference

Prevent Spring Boot Invoking EC2MetadataUtils.getItems on startup

I am having an issue where EC2MetaDataUtils.getItems is being invoked on application start up ( Spring boot app), we do not use EC2 and so the calls made to AWS to get Metadata always fail, the application attempts to get this data 3 times and so this is adding around 15 seconds to the start time of the application.
I have been searching high and low for solutions I found a promising solution would suggested the following #EnableAutoConfiguration(exclude = { ContextResourceLoaderAutoConfiguration.class, ContextResourceLoaderConfiguration.class, ContextInstanceDataAutoConfiguration.class })
However when I try to start up the application it complains that ContextResourceLoaderConfiguration.class cannot be excluded as it is not auto configuration; if I just exclude the other 2 the application still invokes the MetaDataUtils.
Has anyone experienced this in the past and managed to resolve it?
Thank you for your time.

Resolved with the following:
#EnableAutoConfiguration(exclude = {ContextInstanceDataAutoConfiguration.class, ContextStackAutoConfiguration.class, ContextResourceLoaderAutoConfiguration.class})

when running spring-boot-application with AWS dependencies ,
It invokes stack auto-configuration , you need to disable it ,
add following to application.yml
cloud.aws.stack.auto: false

SpringBoot application should not do any call to EC2. This mean your are using some AWS specific library/component/what ever and this library on startup do this call.
Please check your dependencies and context configuration. There are nothing about SpringBoot. There is something with your custom dependencies/components.

If you're not using EC2, you can try removing the spring-cloud-aws* libraries from your dependencies.

You can use Spring profiles to differentiate between cloud and default profiles. For cloud profile, you can use spring-cloud-aws artifact to get metadata about EC2 instance which you need EC2 read permission access from an attached IAM role whereas for default profile, you don't need to worry about cloud environment and disable the cloud configuration properties which should not cause an issue for the application startup.

Dynamically change application.properties values in spring boot

Currently i am working on a REST based project in Spring Boot.
I have added the api url in 'application.properties' file.
i.e.
application.properties
api-base-url=http://localhost:8080/RestServices/v1
And also this 'api-base-url' value access from java.
In some situations i need to change the 'api-base-url' dynamically.
I have change 'api-base-url' value dynamically & working fine.
But my problem is that
when wildfly restart then the configuration will be reset to default.
i.e
This is my default value
api-base-url=http://localhost:8080/RestServices/v1
dynamically change to
api-base-url=http://10.34.2.3:8080/RestServices/v1
when wildfly restart then the configuration will be reset to default.
i.e.
api-base-url=http://localhost:8080/RestServices/v1
Have any solution for this?

You might want to consider using a cloud config server to host your config. Two examples are Spring Cloud Config and Consul.
These servers will host your application's configuration and your spring boot application will make a call out to the config server on start up to get it's config.
spring-boot-actuator exposes the endpoint /refresh which forces the application to refresh it's configuration. In this case, it will call out to the config server to get the latest version.
This way you can change the config hosted in the config server then hit the /refresh endpoint and the changes will be picked up by your application.

As #moilejter suggests, one possible way is to persist in database table and at start time you simply read from that table instead of application.properties file. Your application.properties files can hold information necessary for database connection.
You would also need a JMX method or a REST API to trigger in your application that the url has changed and which inturn, would simply read from same table. This way you would be safe even if app restarts and you won't lose the override.
You can use BeanFactoryPostProcessor coupled with Environment bean to leverage spring placeholder concept.

#user2214646
Use spring expression language

Disable Redis AutoConfig in spring boot when testing

I am trying to disable Redis when I am testing with spring boot. I have disabled my configuration but the auto config created a default connection and fails because it can't connect to a non-existent service. For testing I am content to just use a basic in-memory cache or a no-op cache. That doesn't work either. Here is what I have tried:
per this issue I added said configuration to my test app properties
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration
But. That gets me a bit further. But ultimately I get a NoSuchBeanDefinitionException redisTemplate - this is because redisReferenceResolver is trying to look that up.
Looking at my debugger right now, the bean it's trying to hydrate is:
org.springframework.data.redis.core.convert.ReferenceResolverImpl which is coming from spring-data-redis:1.8.0.RELEASE which is coming from this dependency: compile('org.springframework.boot:spring-boot-starter-data-redis') . I admit, the bean name is a bit misleading. The type it actually resolves to is not
The only other reference to redis is in our hibernate support.
Can someone explain how to turn this off for testing?

Try excluding this two auto-configuration classes in your test properties file:
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration,org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration
or
exclude
org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration
and set: spring.data.redis.repositories.enabled=false

With YAML syntax (& Spring Boot):
spring.autoconfigure:
exclude:
- org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration
- org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration
If you have SystemEnvironmentPropertySource in you app context you can use environment variable SPRING_AUTOCONFIGURE_EXCLUDE separating items with comma:
SPRING_AUTOCONFIGURE_EXCLUDE=org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration,org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration
Also try #EnableAutoConfiguration(exclude = {...}) on a #TestConfiguration annotated class.

If you dont want to change any files/code, you can also do this with an environment variable:
SPRING_AUTOCONFIGURE_EXCLUDE=org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration,org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration

How to update configuration of SpringBoot application at runtime without reloading whole ApplicationContext

I am trying to figure out how can I dynamically update/reload externalized configuration in a Spring Boot application without restarting the whole application.
Most of the advice involves reloading ApplicationContext after changing the externalized configuration, but that is equivalent to restarting the entire application, so this is not really all that useful.
Reading through SpringBoot reference documentation, I found a chapter 23.7 Typesafe Configuration Properties.
If I understand it correctly, this allows to define simple POJO classes that will hold your application (externalized) configuration values as attributes.
In theory at least, this scheme could be used to bind beans only once to the required configuration POJO and upon configuration change just update the values in the POJO. Components could easily pick up the changes next time they access getters on the POJO...
However, I have yet not managed to figure out how to enable this type of behavior. Is there some glaringly obvious way to dynamically update components annotated with #ConfigurationProperties when relevant configuration has changed?

It sounds like you're looking for #RefreshScope which is provided by Spring Cloud. From the Spring Cloud documentation:
A Spring #Bean that is marked as #RefreshScope will get special treatment when there is a configuration change. This addresses the problem of stateful beans that only get their configuration injected when they are initialized. For instance if a DataSource has open connections when the database URL is changed via the Environment, we probably want the holders of those connections to be able to complete what they are doing. Then the next time someone borrows a connection from the pool he gets one with the new URL.

How do I test if EJB is running on JBoss AS 7 server

Again, many excellent answers from the fine folks here on SO. I am still unable to connect. But I believe Gimby might have had a good suggestion that there may be something wrong with the server or the beans. According to the log file generated when JBoss started, my beans have been deployed. The administrator of the server is unable to run the admin console for vulnerabilities reasons so there is no way to see if the beans are running. Is there a command line tool that I could point him to for testing? Is there a simple test I could write that would check the beans? I have tried most everything I have found and others have suggested and keep getting various errors. most times being:
javax.naming.CommunicationException: Could not obtain connection to any of these urls: remote://:4647
I've encountered other errors as I have made changes to various files and code but this one is the most frequent. If the call I make to the bean is right, and that is questionable, then how do I tell if the bean is even running or not>

There seems to be some uncleared situations here.
Still I want to ask you, if your bean got a remote interface.
You could use lookup to find your bean on this server.
You also could deploy for example a RESTservice on your jboss server, which look for your bean locally, so you dont have to specify any connection properties, but you would need the jndi name.
Hope this helps a bit, greets Jerome.