feature: add memcache client with consistent hashring

[htbvo]

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[jchip]

nice! impressive work.

Can you point me to the tests that verifies retrieving the same data would go to the same server?

Also, is there a test that checks and verifies if a server goes down?

• Does it verify that some keys still go to remaining servers?
• Does it verify that the keys on the removed server get redistributed?

Is there a test that verify adding a new server?

• Does it verify that most existing keys remain as is?
• Does it verify that the new server gets distribution?

By the way, I was thinking of doing this back in 2017.

I actually found a hashring implemented in C++ but outdated and I updated it to work.

https://github.com/jchip/node-hash-ring

Why is the bad server tests removed?

This module is used by teams at WalmartLabs for biz critical apps, so as long as existing code and behaviors are left untouched, I am happy to merge and release.

[htbvo]

Hi! Thanks for the feedback, I'll add those test cases shortly. I just wanted to answer this question

Why is the bad server tests removed?

I wasn't able to get that test working node 8 and 10 just yet. As soon as I get that working again, I'll add it back. I created this PR a bit early to get feedback on the direction so far.

FYI, I had to change another test case too since the error that gets thrown is different depending on the version of node.

Were you able to run the tests on versions of node >= 8?