Msg.topic = "X" in a if/else function

[finch6]

Hi all,

I'm having trouble with a flow I'm trying to create - I'm sure there is an easier way of doing this whole flow, if so, please let me know...

I have a "collection" of a few pictures that I want to send to a telegram bot in a random order triggered by an MQTT message.
Attached to these pictures, as captions, I want to have text - also attached randomly.
The format of the last send function node is correct for the Telegram node.

The issue I'm having is with the "Caption Picker" function node. I tried using msg.topic = "Caption" so the join node could get the info, but I can't seem to get it right... I'm assuming the if/else function node isn't formatted correctly or something is not allowing the msg.topic = "Caption" to be sent on...

I want different combinations of picture/text for the messages - as not to have the same old picture/text combo all the time. What would be great would be a random node that output predefined text
I did search the Node Library, but couldn't find anything...

Like I say, if I can do this in a simpler way please let me know.
Thanks in advance everyone

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\"1\") {\n    return {payload: msg1}\n} else if (msg.payload == \"2\") {\n    return {payload: msg2}\n} else if (msg.payload == \"3\") {\n    return {payload: msg3}\n} else {\n    return {payload:msg4}\n}\n\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":460,"y":270,"wires":[["bfe136ab82242bcf"]]}]

[rko]

I think you forgot to add the topic in your Caption Picker function. Try something like

return {payload: msg1, topic: msg.topic }

However, you could just use the msg and add the needed payload to it instead of creating new msg objects:

// ...
if (msg.payload == "1") {
   msg.payload = msg1;
}
// ...
return msg;

Maybe the whole thing can be done easier and more flexible .. but if it works for you ...

[E1cid]

@finch6

What would be great would be a random node that output predefined text

You could define arrays of pics and captions, even load them from a text file if you wanted.

Here is a simple example using a change node. i define the captions and photos there, but you could also feed the predefined payloads in.

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The final JSONata expression will output the formatted payload. The input arrays can be any length.

[finch6]

@rko, thank you so much!!!

@rko

However, you could just use the msg and add the needed payload to it instead of creating new msg objects:

// ...
if (msg.payload == "1") {
   msg.payload = msg1;
}
// ...
return msg;

This worked like a charm!!!

I think something in my IF/ELSE was "kicking" the msg.topic = "Caption" out... At least I think (with my VERY limited knowledge!) But you just showed that a IF/ELSE wasn't necessary, just a IF!!!

I understand there are MANY ways to skin a cat...! And I like learning new ways...
So thank you!!

[finch6]

@E1cid, I like the look of this too
Looks complicated but when you break it down slowly it isn't... Definitely going to explore this avenue too. Thanks so much!!!

[rko]

You're very welcome.

The msg.topic is actually being kicked out because by using return {payload: msg1} you are sending a new message object which only contains a payload variable which is set to msg1.

Have a look at this slightly improved version (similar to what @E1cid suggested):

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The random number is treated as index of an array which contains your texts.

The cat is not skinny skinned yet but we're getting there
(no animals being harmed by running this flow)

[finch6]

@rko, I will take a look in the morning..

I now understand why the msg.topic was being omitted, makes perfect sense when it's explained.

Looking forward to seeing your flow, will check it out tomorrow.

@rko

The cat is not skinny skinned yet but we're getting there

That we are!!!

[finch6]

@rko, thanks so much... I just had a look at your flow above!
Everything is so much clearer wjhen you have direction

I also found this node - random-generator_node-red-contrib - that I could have used... But now I have 3 different ways of doing the same thing..! And I bet I'll use each one in a different project in the future, so thank you @rko & @E1cid, I appreciate it greatly..!

Stay safe everyone!!