Allow to prepare the pool

[goetas]

Hi, this is my first pull request / contribution to a Java project.

I have a need to prepare/warmup the connection pool in advance, and it seems that it was not possible before.

Would a pull request as this be accepted? If yes can can do all the needed adjustments (formatting, tests, documentation...)

This would instruct the LettucePoolingConnectionProvider to warmup the pool before returning the connection.

Thank you!

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[mp911de]

Thanks for reaching out. I would consider the missing call to GenericObjectPool.preparePool even a bug as we do not enforce midIdle. Have you tried calling always preparePool in computeIfAbsent(…) and see how tests behave?

[goetas]

@mp911de hi and thanks for answering so quickly. I have moved the pool preparation to computeIfAbsent. Tests seem green (at least locally for me), I have also adjusted the code style.
I did not add this feature/fix for getConnectionAsync as the AsyncPool seems totally different from the "sync pool" and I could not understand how it is supposed to work.

[goetas]

I would consider the missing call to GenericObjectPool.preparePool even a bug as we do not enforce midIdle

if this is a bug, then maybe i do not need to add an additional config? should i just call preparePool ?

[mp911de]

if this is a bug, then maybe i do not need to add an additional config?

That's how I see it as well.

should i just call preparePool ?

Yes, that should be sufficient.

[goetas]

All changes have been done as suggested