[WIP][mysql] Add ExternalSystemListener to notify user about the status of connector.

[lvyanquan]

this closes #2520

Try to support notification about the status of connector, since it may be a common demand from community.
However, I met some problem when add a preliminary implementation, want to get some advice from yours.

1. When I try to define an enum of ExternalSystemEvent, I found that it's similar to AssignerStatus, can we reuse it?
2. Should we send information about finished splits to listener? then it would be very similar to checkpoint.
3. Should we add a default implement like KafkaListener?

[lvyanquan]

Hi, @ruanhang1993
Not sure if my design and confusion are reasonable, Looking forward to your advice. 😊

[SML0127]

@lvyanquan
Wow..
First of all, Thank you for implementing this function I was hoping for.

I've been so busy at work and was just about to implement it, but you've already implemented it! 🤣🤣🤣

Can I run this pr with our company in-house notification tools and give you some comment??🙇🏻‍♂️🙇🏻‍♂️

[SML0127]

@lvyanquan Wow.. First of all, Thank you for implementing this function I was hoping for.

I've been so busy at work and was just about to implement it, but you've already implemented it! 🤣🤣🤣

Can I run this pr with our company in-house notification tools and give you some comment??🙇🏻‍♂️🙇🏻‍♂️

I added some information (e.g. startupMode, gtids) for notification message and created PR.

As our team implemented and used this notification feature, we realized that the startupMode and gtids information was really useful. So I added it.

I hope you give it a try, and thanks for any comments!! 😄🙇🏻‍♂️

[lvyanquan]

It makes sense to me, and I create an abstract class AbstractListenerMessage since there are other datasources like oracle、postgreSQL.

[SML0127]

It makes sense to me, and I create an abstract class AbstractListenerMessage since there are other datasources like oracle、postgreSQL.

LGTM!
I learn a lot from your implementation😃

[whhe]

This field 'properties' is for?

[yuxiqian]

Is there any progress on this PR? cc @lvyanquan

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This pull request has been automatically marked as stale because it has not had recent activity for 60 days. It will be closed in 30 days if no further activity occurs.

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity for 60 days. It will be closed in 30 days if no further activity occurs.

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity for 60 days. It will be closed in 30 days if no further activity occurs.

[github-actions]

This pull request has been closed because it has not had recent activity. You could reopen it if you try to continue your work, and anyone who are interested in it are encouraged to continue work on this pull request.