I’m using mongo watch() to subscribe to change stream events. I’ve noticed that the change stream events automatically stopped without throwing any specific error and become idle. Then have to restart the server to listen to the change stream again.
I’m not able to find out the specific reason for this strange behavior.
We are using Nodejs server. mongoose for db connection and watch.
If any one of you faced the same issue please guide me on that. We have 1 primary node and 2 secondary node cluster and hosted in mongodb atlas.
2
Answers
The
collection.watch(...)method has to be called on the collection on every server restart. Common mistake is to call it once upon the creation of the collection. However, the database does not maintain reference to the result of this call as it does for other calls such as thecollection.createIndexes(...).Change streams only notify on data changes that have persisted to a majority of data-bearing members in the replica set. This ensures that notifications are triggered only by majority-committed changes that are durable in failure scenarios.
Change stream events stop working when a node fails in a replica set