fix: Connection Instability with socketTimeout Parameter

[pinkiesky]

This PR is fixing redis/ioredis#1919 issue (When setting the socketTimeout parameter to a non-zero value, the Redis connection becomes unstable after startup)

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The problem is that the auth command is sent before DataHandler is created on connection startup. This ruins the correct listener orders--the parser listener shall execute before the other ones.

To avoid this, I replaced on with prependListener to ensure the correct order.

[mcollina]

Thanks for opening a PR! Can you please add a unit test?

[alzinin]

Sure, no problem

[pinkiesky]

I just added the small unit for the changed subscribe logic, but I also noted that we missed commits that add "socketTimeout" to the lib. It happened because the socketTimeout was added after the fork was created

• redis/ioredis@673ac77
• redis/ioredis@558497c

I can propose merging this PR (if you don't mind), and later, we will copy these missed commits to the repo. @mcollina
is it a good way to handle this?

[mcollina]

Can you open a separate PR with those two commits? We'll land that before this.

[mcollina]

lgtm

[mcollina]

The test does not really cover the use case of the bug. Can you add a test that actually reproduce the loop?

[pinkiesky]

The test does not really cover the use case of the bug. Can you add a test that actually reproduce the loop?

The best idea I got is to create functional one for the case. Yes, I will

[pinkiesky]

A functional test for socketTimeout was just added

@mcollina, could you check it and provide feedback please?

[mcollina]

lgtm