Google Wave (sadly deprecated) has pioneered a lot of what drives modern-day Google Docs, Slides, etc. in terms of an OT framework – thankfully, the project has led to a series of whitepapers discussing the technologies present in Wave, and even more happily, the original source code was open-sourced.
Implementing Cormack’s 1995 paper was more straightforward than I anticipated; as per the previous discussion with the author, I went ahead and implemented the corrected dOPT algorithm for a tree topology. The source code at the time of this writing can be found on Github for reference; all tests are passing, and no known bugs exist. Any questions on the source code can be directed to me.Continue reading
In the process of implementing Cormack’s correction to the dOPT algorithm, I’ve come across several other papers which provide a more complete background of operational transforms and may be of use in the future. They are listed here for sake of documentation – a review of these papers will be provided once I read them carefully.
- A Calculus for Concurrent Update (Cormack 1995)
- Proof of Correctness of Ressel’s adOPTed Algorithm (Lushman and Cormack 2003)
- Transformation-Based Concurrency Control in Groupware Systems (Lushman 2002)