Spring-WebFlux | Spring Reactive - Handling Errors at a Functional Level | Architecture library

It seems this is a well-documented issue here on Stackoverflow but it seems non of the solutions are working for me (if I am wrong I'd be glad if someone pointed me to a solution). I was following this tutorial on how to test Webflux controllers in Spring boot. I did what I believe is exactly what is in the tutorial but for some reason, I am getting the error below:

So I have a old working application which uses Spring MVC and not spring boot. I have added gradle dependency of spring-webflux in my project and start using webclient for calling external APIs from my project. This is my webclient handler class:

A normal spring-web application can be deployed to tomcat standalone as war file as follows:

I have a super simple Spring Boot app with Spring Security 5 that authenticates over OAuth2 with a Keycloak 17 instance running in Docker.

Everything works fine when I start the app locally from Intellij.

But when I run the app from a Docker container with docker-compose I get:

[invalid_token_response] An error occurred while attempting to retrieve the OAuth 2.0 Access Token Response: I/O error on POST request for "http://localhost:80/realms/Demo/protocol/openid-connect/token": Connection refused (Connection refused); nested exception is java.net.ConnectException: Connection refused (Connection refused)

when I input the credentials on the keycloak login page. But there is a session created for that user in keycloak.

System:

• MacBook with Monteray 12.0.1
• Docker Desktop 4.5 with Kubernetes 1.22.5

docker-compose.yml

I need to write some code to manage files for a spring-webflux service. The first instinct is to use File/Files which work fine in a regular app, but they're blocking.

So, I googled most of all criterias I imagined but all results were mostly related to uploading/downloading files.

My question is - is there any way to manage files (delete,copy,move) in a non-blocking fashion under spring-webflux? Even a 3rd party lib?

I am working on a project and trying to use the GraphQL backend server in my SpringBoot application. I have written a client which connects to graphQL backend and creates/fetches the data but when I am trying to pass the variable from the application and pass with a query then it's throwing an error. But it's working fine if I just comment the variable part and hardcode the value directly in query.

Mutation Query- mutation($names: String!) { createList (name: $names){ updated listId name } }

Variable - { "names" : "bagName" }

Java Client -

'''

I am using Java 17, spring-boot 2.6.3 with spring-webflux and spring-consul dependencies and I have the following class:

I'm trying to set up security for Webflux with OAuth2 to use it as a gateway. On the other hand I have my own Authorization Server. We can say that this is the structure I want to achieve:

The configuration is as follows:

WebFluxSecurityConfig.java

I mimic tutorial at https://howtodoinjava.com/spring-webflux/spring-webflux-tutorial/ . My MongoDB (My version https://fastdl.mongodb.org/windows/mongodb-windows-x86_64-5.0.5-signed.msi). Postman v9.8.0 , Windows 10 x64.

My controller