Help with `delay` node set to `rate limit`

[Trying_to_learn]

Ok, so new problem.

I have a delay node set to rate limit.

Is there a way that if it has messages queued up (queueing up?) and the first one completes, can I send the node a signal to send the next message?
As in: not peek at it, but actually step to the next message.

Thanks.

[cymplecy]

I recommend node-red-contrib-queue-gate (node) - Node-RED when doing this sort of thing

[marcus-j-davies]

I’ll throw my hat in this one

@marcus-j-davies/node-red-semaphore-plus

May help you also, may not - but just in case

[Trying_to_learn]

@cymplecy
Thanks!

Forgot I had that.

Not to add more nodes, I'll use it.

Silly me for forgetting I had it.

[jbudd]

Does sending a message with no payload, and msg.flush = 1 not release the next message from the delay node?

[dceejay]

Sending in msg.flush set to a number will release that many right away. So msg.flush=1 will release the next message

[Trying_to_learn]

That's a point of contention.

FLUSH.....

So that sends the next message or PEEKS at it?

I seem to remember the latter.

That causes all sorts of trouble.

OK, I was wrong.

Thanks. That maybe nicer to apply.

[Colin]

Here is my standard flow, using a delay node, for handling messages sequentially. Open the comment node for full details of how to use it.

If you want to include a retry feature to retry messages that fail for some reason (for example sending email messages where the send may fail) then you can use @colinl/node-red-guaranteed-delivery.

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[Trying_to_learn]

Thanks.

Just completed something just like that.

[TotallyInformation]

You may already have this built-in but there should probably be some kind of limiter on the total number of messages queued? In theory, it would be possible to crash Node-RED without any limiter I think?