Output component doesn't print when following MsgFlo tutorial

[d-e-h-i-o]

Hi,

I am following the MsgFlo tutorial and the core/Output component does not print the message on console, even though it receives it.

I did some debugging at it looks like the component receives the IP, but returns at Output.js:36 at the statement:
if (input.attached('options').length && !input.hasData('options')) { return; }
The line was added in 9b83e7c.

I don't really understand what the purpose of this line is.

Debugging information is:
noflo-runtime-msgflo:newrelic Transaction.open 1 +1s
noflo:component null port 'in' entered auto-ordering mode +0ms
noflo:component null packet on 'in' didn't match preconditions: data +3ms
noflo:component null packet on 'in' didn't match preconditions: closeBracket +1ms

I also printed out the IP buffer as it is at component level, and there are both opening and cloing bracket IPs present. Reading the error messages, it seems that the IPs did not cause the component to activate.

Also only one message gets delivered. When I restart the component, the next one gets delivered. Does it not acknowledge the messages?

Does anyone has an idea what is going on?

[d-e-h-i-o]

So it seems that the Output only prints when it receives data at the OPTIONS port, and the tutorial was not designed in a way. that such an IP will be send. I submitted a pull request for the msgflo usage tutorial, which should fix this issue.