Add support for Tablestore from Alicloud as the new storage backend

[opan]

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[porunov]

Thank you @opan for the contribution!

It's always great to see new storage implementations. However, usually adding storage implementation directly into JanusGraph adds some burden if there are no active contributors for such storage implementations.
Thus, JanusGraph supports storage adapters which can be developed outside on the main JanusGraph code base and they work as plug-in systems.
For example, we have FoundationDB storage adapter located here: https://github.com/JanusGraph/janusgraph-foundationdb
There are also other storage adapter like:
Aerospike: https://github.com/PlaytikaOSS/aerospike-janusgraph-storage-backend
DynamoDB: https://github.com/amazon-archives/dynamodb-janusgraph-storage-backend

Would you consider converting your storage implementation into a storage adapter? If community wants and there are people willing to maintain it then we can also onboard this storage adapter under a separate repository hosted inside JanusGraph organization for wider adoption.

Btw. we have janusgraph-dev mailing list where we usually discuss such contributions.

Let me know what you think about it.

[opan]

Hi @porunov , thank you for the response! I think I'll have to discuss this with my team first and after that will get back here with some updates whether we are going to pursue merging this with janusgraph code base or follows the plug-in systems like those samples you have shared.

[opan]

btw, forgot to ask, is there any docs or guides on how to create plug-in for a new storage backend in janusgraph?