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Can't Discovery-Locate Config Upon Transition to Spring 2.4

Versions
Spring Parent: 2.7.4, Spring Cloud Version: 2021.0.4, Java Version: 11
Issue
My Spring service has been using Eureka to connect to the config server for a long time, but I want to upgrade to Spring 2.7.4. I understand that as of Spring 2.4, the bootstrap context has been deprecated (source) and I need to make some adjustments to the old bootstrap properties and move them over to application.properties.
The documentation for Spring Cloud specifies that in order for me to continue to use discovery-first config lookup, I need to define a spring.config.import property with an optional configserver entry (source). Since I'm also using Vault, I define the property as follows:
spring.config.import = optional:configserver:placeholder,vault://<my-generic-backend>/dev
Next, I need to define the following properties (source). These properties were already defined in my old bootstrap.properties, so all I need to do is copy and paste.
spring.cloud.config.discovery.enabled = true
spring.cloud.config.discovery.serviceId = config-server
eureka.client.serviceUrl.defaultZone = <my-eureka-url>
Unless I'm missing something, these are all the steps I need to take in order to upgrade to 2.7.4. However, when I run the Spring service, it complains that it can't find the config server (via Eureka, or via URL), then it registers successfully with Eureka, and then continues trying and failing to find the config server.
Here is some of the output of the program:
> Running with Spring Boot v2.7.4, Spring v5.3.23
> Could not locate configserver via discovery: No instances found of configserver (config-server)
> Could not locate PropertySource ([ConfigServerConfigDataResource#2aa6311a uris = array<String>['placeholder'], optional = true, profiles = list['local']]): Invalid URL: placeholder
...
> DiscoveryClient_<my-project-name>/local - registration status: 204
I understand why it's failing to find a config server at URL: placeholder since that's not a valid URL, but I don't understand how the service can successfully register with Eureka yet not be able to find the config server. I know the service is registered because the output of the program says it registered correctly (and I can see it in the registry), and I know that the config server has the correct entity ID (config-server) because it was copied and pasted from the old bootstrap (and I can see config-server in the registry).
Workaround with Hardcoded URL
When I hardcode the config server URL like this (and set spring.cloud.config.discovery.enabled to false), the config is loaded properly from the server:
spring.config.import=configserver:https://<my-hardcoded-config-url>.com,vault://<my-generic-backend>/dev
Workaround with Bootstrap
It's possible to return to using the bootstrap context and still use Spring 2.7.4 with discovery-first config lookup by adding the "spring-cloud-starter-bootstrap" dependency. So I added the dependency to my POM and moved these properties back to bootstrap.properties from application.properties.
spring.cloud.config.discovery.enabled=true
spring.cloud.config.discovery.service-id=config-server
I moved the Vault and Eureka properties back into bootstrap.properties as well. The new application.properties now contains no values relating to Eureka, Vault, and Cloud Config.
When I run the service, it does indeed find the address for the config server through Eureka, as expected (although it fails to connect because it's the internal address and I'm running locally).
Conclusion
While these are valid workarounds, it's frustrating to not be able to have a dynamic URL for the config server (as is the entire point of using Eureka). Right now, it looks like my choices are either to use a hard-coded URL and risk having to change every property file, or use a deprecated behavior that Spring documentation specifically disfavors (source).
I would appreciate any guidance you have on the issue, and I thank you in advance.

Vaadin 14 how to move the vaadin servlet to a different URL?

I have a pretty basic vaadin application running. The application is spring-boot backed and I defined some rest API.
I've added OpenAPI documentation using org.springdoc:springdoc-openapi-ui:1.4.4, which worked perfectly before adding vaadin.
After adding the vaadin dependencies as shown in the vaadin spring-boot tutorial, and creating a view (which works), the swagger UI is no longer reachable.
It seems to me that vaadin completely takes over all web requests. Digging deeper, I've found that vaadin registers a new servlet and catches all requests.
I don't find any docs on how to configure this -- I'd expect that one could configure vaadin such that it serves UI from a different path, say /ui or similar.
I've tried to set
vaadin:
url-mapping: "/ui/*"
in my application.yaml -- but this results in blank pages (no errors) for my vaadin views,
and the vaadin servlet does still take over /.
I use spring.boot 2.3.2.RELEASE, vaadin 14.3.1.

The value to override is (note the camelCase instead of the kebab-case):
vaadin:
urlMapping: /ui/*
Using the kebab-case did (does) not work. As expected, this is a bug. See https://github.com/vaadin/spring/issues/637
From the docs at the point of time:
You can set properties for Spring Boot in your application.properties file.
Example: Setting Spring URL mapping in application.properties.
vaadin.urlMapping=/my_mapping/*
By default, URL mapping is /*.
An additional servlet, such as /my_mapping/*, is required to handle the frontend resources for non-root servlets. The servlet can be defined in your application class. See this Application class for a example.
Source: https://vaadin.com/docs/v14/flow/spring/tutorial-spring-configuration.html#using-spring-boot-properties

How to make Sprint Boot 2 actuator path based on application properties?

I have a microservice application with Spring Boot 2, which used my own library to propagate new endpoint to itself by using actuator functionality - my own actuator implemented an MvcEndpoint interface, and contained 'path' variable which got real API mapping from application.yml of microservice that used this library.
But after I recoded my library to spring boot 2, I have an issue - id property on #Endpoint annotation contains only constant value (as every annotation properties), and I haven't found way to change API path of my actuator endpoint to something like '/api/v1/my-service/my-actuator-endpoint'.
I tried to write this in my application.yml of microservice:
endpoints:
my-actuator-endpoint:
path: /api/v1/my-service/my-actuator-endpoint
But this endpoint still accessible only from /my-actuator-endpoint , which means only by its id.
How can I make this be accessible by custom path like /api/v1/my-service/my-actuator-endpoint, which will be configured in application.yml?

Problem solved, needed to add this property to application.yml:
management:
endpoints:
web:
path-mapping:
my-actuator-endpoint: api/v1/my-service/my-actuator-endpoint

you can expose actuator endpoints by setting configuration in property file like this
management.context-path=/manage

What is the right approach for extending Spring Cloud Config Client?

I want to replace Basic Authentication for Spring Cloud Config Server with oAuth implementation. Let's leave Config Server alone for now and focus on changes for Config Client. Obviously I don't want to write my own implementation for whole thing, but instead execute my own logic and fallback on standard Config Client. Also I have to pack my changes into library since I will use it in multiple micro-services.
Long story short I want to achieve following:
1a. Create custom Starter which will contain Spring Cloud Config Client as dependency. Is it even doable or necessary?
or
1b. Create custom Starter with only my custom logic which will be executed before Spring Cloud Config Client. In this case each micro-service will have Spring Cloud Config Client and custom Starter as dependencies. How can I manage execution order and inject custom logic results into Config Client?
2.Introduce new bootstrap settings. e.g. spring.cloud.config.custom.username and spring.cloud.config.custom.password (Optional).
3.Introduce custom annotation for custom Starter. e.g. #enableCustomConfigClient (Optional).
I started with building custom Starter with following code in /resources/META-INF/spring.factories:
# Bootstrap components
org.springframework.cloud.bootstrap.BootstrapConfiguration=\
com.example.greeter.config.ConfigClientBootstrapConfiguration
But this code invoked after profile is set, not the first thing like Config Client does.
Any suggestions and especially code samples are appreciated. Thanks!

Posting approach I chose for future reference.
Create new package which will be executed on top of / before Spring Cloud Config Client. Two main features here:
Create file src/main/resources/META-INF/spring.factories with org.springframework.cloud.bootstrap.BootstrapConfiguration={YOUR_CLASS}
In {YOUR_CLASS} apply custom logic. Don't forget to use #org.springframework.core.annotation.Order({YOUR_PRECEDENCE}) and fact that Ordered.LOWEST_PRECEDENCE will be executed first
Build jar from previous step and include it into your project (as local file or via artifactory)
Add Custom logic to Spring Cloud Config Server so it can use JWT.
Working example is here: https://github.com/ka4ok85/spring-cloud-config-client-jwt

Runtime loading of Controllers for Spring MVC and dynamically mapping requests/URLs

We are starting a new project using Spring MVC, and we would like to move away from annotation-driven request/url mapping. We wish to implement the following use case:
Use Case A
User enters a URL.
The request mapping handler retrieves a list of mappings (e.g. from the DB), and based on this dynamic list of mappings, it calls the relevant controller.
This is because we want to be able to do the following as well:
Use Case B
We want to load a new Controller (perhaps a new reports module) into the web app without having to redeploy or do a server restart.
We will map this new Controller to a URL and persist it somewhere (most likely the DB).
We would like the Controller to be registered in the Spring app context (managed by Spring).
We would then like to use this new Controller in the request mapping.
We've taken an initial look at the different ways we can implement this, but we are unsure of the best architecture/method to go about this route. A couple of questions:
For Use Case A, how do we implement this within the Spring MVC framework (or if it's possible)?
For Use Case B, is there a good framework or way to be able to do dynamically loading and registering of this for web applications? We've taken a cursory look at OSGI but it seems to be advisable for use in non-web applications.

For Use case A :
Instead of DB you can keep the url mappings in a property file and then use property place holder to initialize beans using xml configuration on context up. This way remaining inside the spring framework, you can avoid annotations.
For Use Case B :
Tomcat supports dynamic reloading of classes but that to of only non structural changes in class file. But this has memory leaks as well as it doesnt cleans up old instance of class loader rather it creates a new instance.

Its quite achievable using spring-mvc-router API.
Please check below link
url-action mapping & routing in Spring MVC 3.0
Here the URL can be configured to controller.method using .conf file, but this can be achievable using java configuration, and i haven't tried so far.
Also if xml configuration chosen, then check out the property 'autoReloadEnabled', but its not adviceable for production use.
Hope this helps!!!