ExternalConfig Array Merging Issue in Kubernetes vs Local Environment

[vineeth-au]

I've been troubleshooting a configuration merging issue for the past few days without success, so I'm hoping someone here can help.

Environment Details:

spring-boot-dependencies: 3.3.12
spring-cloud-starter-bootstrap: 4.1.4
spring-cloud-dependencies: 2023.0.3

Deployment: Kubernetes cluster

Configuration Setup:
I'm using environment-specific YAML files: application.yaml, application-dev.yaml, application-staging.yaml, and application-prod.yaml.

application.yaml (base configuration):

my-application-name:
  action1:
    - "Item 1"
    - "Item 2"
    - "Item 3"
    - "Item 4"
    - "Item 5"

application-dev.yaml (environment override):

my-application-name:
  action1:
    - "Item 1"
    - "Item 6"
    - "Item 7"

The Problem:

When running locally, the configuration behaves as expected. However, when deployed to Kubernetes, the action1 array becomes: ["Item 1", "Item 6", "Item 7", "Item 4", "Item 5"].

This appears to be merging arrays rather than completely overriding them, but only in the Kubernetes environment. This is quite similar to the issue mentioned here.

[wind57]

can you provide a sample to re-produce this issue please? If I can see it in action, I can take a closer look on what is going on. thank you

[vineeth-au]

Fair enough. I saw this behaviour in our cluster, but unfortunately not when running locally. Give me couple of days and I'll try to make up a hello-world example (I'm thinking minikube) where this behaviour can be replicated. Is that ok?

[wind57]

that would be perfect

[vineeth-au]

Morning, @wind57 ... Hope you are doing good. Did not get a lot of time to work on this during the weekend and before I can submit any code I will need to check my company policies. Can I have until the end of this week to get back to you?

[wind57]

no worries at all, take your time

[vineeth-au]

Figured I'd give you an update. I was able to reproduce the issue on minikube!!! We are in the process of getting clearance from legal. Will keep you updated.

[vineeth-au]

Hey @wind57 , how are you doing? We got the all clear!!! Here is a hello-world example with the issue being reproduced. Let me know what you think. If you have any questions, feel free to ping me and we can sync up...

[vineeth-au]

FYI: We are using SpringBoot 3.3.12 (with compatible dependencies), however in this example I've used the latest version(3.5.0), for couple of reasons:

• To verify & validate this issue is present in the latest version.
• Make your life easier 😃 (hopefully)

[wind57]

Thank you. I will take a look next week, since Im on vacation.