I'm keen to hear other people's thoughts on the choice of an event store for Akka Persistence for doing CQRS.
As mentioned in my other post, I believe that Akka Persistence only provides part of the story for CQRS (but a very important part) and that other stores will most likely be needed for query models (both SQL and NOSQL stores). Since they are project specific I would like to focus here on what store is "best" for Akka Persistence for CQRS. Right now my leading contenders are Kafka and Event Store (but I haven't thought too much about Cassandra or MongoDB etc). My knowledge of all of these is limited so please excuse and correct me if any of my statements are wrong. KAFKA: Apache Kafka is publish-subscribe messaging rethought as a distributed commit log. Persistent topics for publishing and subscribing Highly scalable and distributed Need to manually create topics for projections Each topic has own copy of events Writing to multiple topics is not atomic Allows logs to be kept for different amounts of time Battle tested technology from LinkedIn Not generally used a lifetime store for events http://kafka.apache.org https://github.com/krasserm/akka-persistence-kafka/ EVENT STORE: The open-source, functional database with Complex Event Processing in JavaScript. Built specifically for storing and projecting events Store event once and create virtual projection streams Journal plugin at early stage in development Projections are still beta but finalising soon JSON serialisation (which has +ve and -ve points) Javascript for projection stream specification Atom interface helps with debugging Not as distributed or scalable? Includes temporal criteria for streams http://geteventstore.com https://github.com/EventStore/EventStore.Akka.Persistence Personally, I like the potential Kafka has to be the event store / log for CQRS but also the store for logs in big data processing and analytics. However, the fact that events need to be manually replicated to different topics and problems that would be caused if this wasn't consistent is a worry. On the other hand, Event Store has been specifically designed and built for event store and projection processing by a leader in the field of CQRS. However, it uses a unique set of technologies and I am not sure of it has been battle tested by many or its long term viability. What do others think? What are your thoughts of and has your experience been with other stores? MONGODB: ? CASSANDRA: ? As mentioned, I can definitely see the use of the last two for query models in addition to one of the event persistence and projection stream store but have not really considered them for the latter myself. Of course, enormous kudos and no disrespect to any of these fantastic free and open-source projects Thanks in advance for sharing any thoughts / experiences. Cheers, Ashley. -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
