Operational Transformation library?

Question

I'm looking for a library that would allow me to synchronize text in real-time between multiple users (ala Google Docs).

I've stumbled upon Operational Transformation, which seems to fit my needs. Having said that, I understand the gist of OT, but not the math nor implementation of OT.

Thus, I was wondering if there was a drag'n'drop Javascript library that would hook into a text area, generate the transforms, then allow me to apply those transformations onto another client?

(I've gotten the Etherpad source, but I can't make head or tails out of it. If anyone could point out how to leverage on Etherpad's OT implementation, that'll be great too!)

Answer 1

I think that parts of Google Wave's OT implementation are Open Source (and more parts are coming).

I'm not sure if this is what you are looking for:

• Google-Diff-Match-Patch - Diff, Match and Patch libraries for Plain Text: "The Diff Match and Patch libraries offer robust algorithms to perform the operations required for synchronizing plain text."
• Google-MobWrite - Real-time Synchronization and Collaboration Service: "MobWrite converts forms and web applications into collaborative environments. Create a simple single-user system, add one line of JavaScript, and instantly get a collaborative system." (Uses Google-Diff-Match-Patch.)

Answer 2

Try beWeeVee http://www.beWeeVee.com Is a framework based in .NET that you can freely use for non-commercial use, although there are some partnership agreements for commercial. Good luck!

Answer 3

Execuse me that this post is not an answer, but another question based on the original one.

I am also using Google-Diff-Match-Patch to implement OT, which works greatly for plain text. But when try to support rick texts, sth like making texts bold or italic, google-diff-match not works as expectedly, for example when embedded styles like <b> and <i>, the diff results messed up.

Not sure should go on with google-diff-match algorithms or try something else, but really no better one so far than this library. Could anyone tell some direction what to do next? Thanks in advance.

Regards,

Steve

Answer 4

You could talk to the guys at Cedanet. Though Ceda is closed source and no free trial is available on their web site. I have been involved in the development of Ceda and continue to work with it in commercial projects, so I might be able to provide some feedback/advice if you head down this path.