Sending location data from Node-RED to Map widget

Need Help With My Project
1

I’m trying to send location data from Node-RED to Map widget, however, nothing shows up in the interface.

The function, which generates the message is:

msg.payload = [2,47.488,19.135,"may"];
msg.pin = 15;
return msg;'

The message then fed into an - otherwise working - Pin Dynamic Write node.

Anyone could help fo figure put the appropriate payload format, to get the map widget working?

Thanks,
regards,

András

2

I’m not sure that the standard write Node is capable of being used with the map widget.
Other widgets that need more complex data structures, such as Table & LCD have their own nodes.

@gab.lau should be able to tell you if it’s possible with the current ws contrib. if it’s not, then I guess it could be done using a Blynk API call from Node-Red.

Pete.

3

Hi András,
I’m not at home for next 3 weeks, so no test or debug sorry :grinning:

From the official docs it’s ok to use a write node to send data to map widget.

You can try to pass array of string, like this:
msg.payload = ["1","47.488","19.135","may"]; msg.pin = 15; return msg
The first parameter is an index, try to start from number 1.

Let me know

Best regards
Gabriele

1 Like
4

Hi Gabriele,

thank you for the fast reply, unfortunately, passing all parameters as string did not help. I’ll investigate the problem further in the following days.

Regards,
András

5

Ok,

so the trick is in the line 35 of blynk-ws-out-write.js:

var payload = Buffer.isBuffer(msg.payload) ? msg.payload : RED.util.ensureString(msg.payload);

This will stringify anything but buffers, changing it to:

var payload = msg.payload;

made things work instantly, while it may produce other conflicts. Creating the appropriate buffer is the other option, I have to look deeper into that.

Regards,
András

1 Like
6

You are right!

Change from this:
var payload = Buffer.isBuffer(msg.payload) ? msg.payload : RED.util.ensureString(msg.payload);

To this:
var payload = Array.isArray(msg.payload) ? msg.payload : [RED.util.ensureString(msg.payload)];

It is more correct that the payload variable is an array.

Let me know

Gabriele

7

For now, I can’t see any downside of not converting payloads at all. Will look deeper into that a bit later, I need some holiday now :wink:

András