simple-datastore simplifies complex business data models to be stored on Google Datastore
We develop and operate an important quantity of massive games, having +16M users. Every game has a complex and always-changing data model, such as any complex application has.
Major problems that simple-datastore addresses are:
| Challenge | How |
|---|---|
| Feature changing is usual. They impact in the data model and they have to be deployed very quickly | Adding a new attribute requires adding it to a Java object: no mapping is required, no "ALTER TABLE" scripts, no migration of old rows |
| Downtime should be avoided as much as possible | No need to stop a running app. Deploying a new version automatically deploys a new model. The migration occurs when the entity is loader, with no overhead |
| Reducing Google Datastore paradigm learning curve | Because of even higher abstraction level when modeling |
| Achieving very high performance | Little reflection usage, very little extra steps on entity convertion to model |
- Complex business object data model conversion to single Google Datastore Entity
- Automatic migration of models versions
- Handy data access methods for common DatastoreService features (Queries, CRUD on both synchronous and asynchronous model)
- JSON based fast Java objects serialization
- Easy, declarative way to model
- Very low overhead, extreme reduction of queries when materializing a persisted model
- Support for massive, parallel data access outside of Google App Engine
- Useful MemCache strategies on data access
- Retrying algorithms for all Google App Engine calls
- Data access logging for performance tuning
- Common business object behaviour: equals/hashcode, lastUpdateTimestamp, several helper for getting information about update events on the Entity and toString showing entity data
- Audit hooks for data change
- Easy and transparent way to store and retrieve complex app parameters
- It works! simple-datastore concepts are a part of our architecture core for running games with tons of users
- Check some examples
- Follow the Starting Guide to include simple-datastore in your project
- Check other advanced examples
The following simplified class diagram shows a little part of our always changing game model for one game:
The idea behind simple-datastore is to persist those object instances in just one Datastore Entity but allowing the program to deal with the same class diagram shown above.
Why simple-datastore is different to objectify-appengine
Objectify is a very nice and mature project. I believe simple-datastore is different because of simplicity:
- The main idea behind simple-datastore is to keep most of the model in just one Entity
- simple-datastore doesn't have entities relations and doesn't expose Key and other JPA/JDO features
- You could say simple-datastore is less powerful but simpler.
- Even though the simplicity, this is still being the core of our complex model for massive games
We would love to get your contributions! If you spot a bug, then please raise an issue in our main GitHub project; likewise if you have developed a cool new feature or improvement in your simple-datastore fork, then send us a pull request!
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0