[Feature] Allow modules to extend Dubbo application configuration

[walklown]

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Apache Dubbo Component

Java SDK (apache/dubbo)

Descriptions

Allow modules to extend Dubbo application configuration to support custom configuration in other modules. For example, I expect to define MetricsConfig in the dubbo-metrics module and PromethusConfig in the dubbo-metrics-promethus module. And in the future, I expect to define OtlpConfig in dubbo-metrics-export-otlp.

Related issues

Separate the code for indicator monitoring Refector Metric export

Are you willing to submit a pull request to fix on your own?

• [X] Yes I am willing to submit a pull request on my own!

Code of Conduct

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[walklown]

Example : https://github.com/walklown/dubbo-pr/commit/043561fe9fb79c762876f89cd6e428a8a4f12b39

Question :

1. AbstractConfig can be removed so that the Config class will be more generic . Is this improvement necessary? I hope to get some suggestions
2. Is SPI a good way to implement extended configuration classes? Any better suggestions?

[AlbumenJ]

@chickenlj @CrazyHZM @icodening @EarthChen @oxsean PTAL