@madelson Thank you for the links. What I found interesting about this specific library was support for Azure, MySql, SQL Server, Local (File, Wait Handle), and Oracle. My employer uses all all of those and Mongo, and a few other NoSql stores.

I've spent the last two days, trying to get my head around how the library works, so I could implement a Mongo provider. Conceptually it all makes sense. Understanding the actual implementation is not going well. All the interfaces are a bit overwhelming.

When I dig into implementation specifics, I get total confused with all the interfaces and the use of internal classes. Having a reference implementation, even if it a duplicate of an existing one, that just uses the public interfaces/classes would make it easier to build a Mongo implementation.

Talking Mongo specific, depending upon the version of the server there are different ways to achieve the same result. Using a BSON document with a two phase approach works on all versions.

The collection for the locks would have a unique index on the lock name field. The document that represents the lock would have several fields including lock name, id, lock state, etc.

When a lock is requested I plan on inserting a document with the lock name, unique id and an initial state of "initializing". If successful, I can then finalize the lock by setting lock state to "acquired", duration to expiration, last renewal time and a few other fields.

If there is already a document for the lock, a duplicate key error will be thrown. Then I could figure out if the existing lock is valid or expired and handle appropriately.

I haven't come to a decision on whether to use a separate sweep task to manage lock expiration.

As for contributing, that might be an issue. I have certain constraints from my employer. We are not prevented from using Open Source, At the same time, code I develop as part of my job is not mine to contribute.

End result, I'm really interested in seeing a reference implementation that doesn't rely on internals.

Cheers.

MongoDB Implementation? #121

Description

Metadata

Metadata

Assignees

Labels

Projects

Milestone

Relationships

Development

Issue actions