To achieve horizontal scalability, I created a cluster using Node.js cluster module + express and it generally worked well. But when I click on "deploy" button after editing a flow, I don't know where my change was deployed to. It seems the changes are active only after I restart the runtime process. Is there a way to deploy changes from editor to multiple node-red runtime?
No. If you've created a cluster of runtimes you need to figure out how to update them all when the editor deploys changes.
For example, a custom storage plugin that notifies all your instances when it receives new flows.
Thanks a lot for the immediate advice.
So, after I receive the new flow, is there a API to add the new flow into the runtime or I should just restart myself to apply the new flow?
How can I make sure my current messages get processed completely when I restart my process? Will my message dead in the middle of the flow?
Hi Fangzhu, Were you able to fix this issue ?
@divyanshverma I couldn't find a straightforward way. Instead I let the flow to be deployed first, save the JSON on disk, then restart all processed using the JSON.
We are still doing evaluation to deploy to multiple processes under a express cluster without restarting process. I am thinking to let the cluster master to pend request to processes one by one then send deploy request and resume.
Thanks for getting back, so here what I have done so far. I was not sure if this is the best way 
- Emit an event when the flow is saved to the database (Using mongodb)
- Broadcast the event to the other processes via pm2 messaging
- On the other process, recieve the event and then call the red api "/flow" to reload/restart the changed flow only.
