Mongo Replicator is a real-time replication tool for MongoDB replica set. It use Change Streams to fetch real-time data changes, with which users can sync data to other containers in real time.
Change Stream require 3.6 or higher version of MongoDB, and is only available for replica set.
For watch scope, deployment or database level is available for 4.0 or higher version of MongoDB.
For ChangeStreamOptions, startAtOperationTime require MongoDB 4.0, and startAfter require MongoDB 4.2.
Mongo Replicator consists of Collector, Replicator and Operator.
Collector represents the data source to watch.
You can set the watch scope when creating a Collector instance. According to the params, the data source can be a deployment (either a replica set or a sharded cluster), several databases or collections.
NewCollector(uri string, databases []string, collections []string) *Collector Collector has a Collect method to perform the watch action.
(c *Collector) Collect(opts ...*options.ChangeStreamOptions) (*mongo.ChangeStream, error)See ChangeStreamOptions to customize your change streams.
Replicator is the unified interface to perform the replication. It is initialized by an Operator and has only one method Replicate.
func (r *Replicator) Replicate(e model.ChangeEvent) error Operator interface defined the methods need to be implemented for the target container to deal with change event documents.
type Operator interface {
Insert(model.ChangeEvent) error
Delete(model.ChangeEvent) error
Replace(model.ChangeEvent) error
Update(model.ChangeEvent) error
Drop(model.ChangeEvent) error
Rename(model.ChangeEvent) error
DropDatabase(model.ChangeEvent) error
Invalidate(model.ChangeEvent) error
}You can implement your own Operator to customize the replication logic.