Docker platform

[gsvarovsky]

m-ld for Docker is coming soon. Please +1 this issue to vote for it.

m-ld for Docker bundles the Java m-ld engine with a REST API, so that it can be used in microservice architectures. For example it can be used as a backup clone in scenarios that require a high degree of data safety.

[gsvarovsky]

Additional motivation: using a backend m-ld engine as an interim measure when developing the idiomatic API for new platforms. E.g. 👇

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The core m-ld protocol is still in motion, so our idea here is to learn as much as we can with a simulated engine before diving into a full implementation. However, the simulation itself should be as useful as possible right from the start!

We can learn a lot with a local un-synced JSON-file backend, but we should move as fast as possible to something with some sync, to shake out how the API behaves with concurrent changes.

So one idea is to implement a back-end sync service, deployable locally with Docker and also on the cloud. This service would use m-ld-js internally and expose the clone JSON API via HTTP. Since this introduces the possibility of concurrent clients, we'd implement some naive optimistic locking just to ensure data integrity. So some transaction commits may incur a lock violation; which you wouldn't see if you used a local m-ld engine.

Originally posted by @gsvarovsky in #97 (comment)

[mcalligator]

Having containerised the timeld time-tracking application for Docker, the ground is now prepared for generalising this to m-ld itself.

[gsvarovsky]

Repository created: https://github.com/m-ld/m-ld-gateway

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UPDATE: The Gateway is now deployed on the cloud using Docker! @mcalligator : we just need to apply your security goodness, test it for use as a 'sidecar' container, and push it to DockerHub!