Tag Archives: Node-Red Debugging

To Weather or not to Weather

That’s it – I’m giving up with OpenWeatherMap. I’ve been having trouble recently with it accepting Hexham,UK some days and not others and it is getting worse – when you look at it’s search list it says Hexham,GB (despite the fact that I have to put in UK and not GB for it to work at all) – then sometimes it can’t find it at all. Someone is having a laugh. Secondly for 2 days it was MISERABLE here in Bellingham just a few miles North of Hexham – and OpenWeatherMap said it was “clear skies” – I’ve not seen blue sky since Thursday until today.

Meanwhile, forecast.io is spot on – see above. See this blog item for how to extract data - https://tech.scargill.net/the-weather/

So you will have noted that I’ve been messing with weather for some time and one of the issues I’ve had is debugging! The standard debug tool that comes with Node-Red is fine but has limited capacity and has no processing capability – for example if you fire a bunch of JSON at it, it looks HORRIBLE (for those not in the know, JSON is a standard, like XML but in most cases very simple, for sending data – simple text).

And it was with that in mind, when mindlessly trawling the web that I stumbled on a reference to a debugging FLOW for Node-Red which would treat text as text and would format JSON – but more’s the point – in a separate browser window – THAT caught my attention.

So – here is the article that started it all off for me this evening…  http://flows.nodered.org/flow/b0fcb7b72fc05a30e55b

Take PARTICULAR notice of Julian’s “Configuration” notes which came about as I completely messed things up and Julian very kindly helped me and then updated his documentation accordingly.

So what we’re doing here is sending debug info to a Node-Red web page – a great idea – but it involves having access to a static library…. /js/mqttws31.js and Julian in his debug notes now tells you how to ensure that Node-Red knows where to look – I would imagine that this info is also awfully useful for node-red-config-ui if you’re planning on adding libraries!!! Certainly added to my knowledge.

And so NOW when I fire out debug info from forecast.IO…..


Using the debugger

“Debugger” is the sub-flow that Julian has created (I just renamed it and stored it all in one sub-flow) and “readable debug” is this…

return msg;

The timestamp just triggers an action every 5 minutes and at power up – sensibly every 15 minutes is actually enough. Then there is the grabbing of data from forecast.io where xxxx  is your API key – freely supplied – and note I output as a “parsed JSON object”.

HTTP node setup


Then I bang the stuff into a global variable for later use.


and finally I add a topic for the new debug

return msg;

And so now instead of garbage coming out of the regular debug when I’m testing the weather I get….. wait for it – in the new debugger…. perfectly readable English!!!

Debugger output

Isn’t that wonderful – and as you have the source you could imagine all sorts of variations on this. I am SO chuffed about this – a genuine reason to buy MORE MONITORS!!

Here’s what the debugger sub-flow looks like…

Debugger subflow