RPi 3 - Sending back boolean value to Losant API


#1

I have been having some trouble following the tutorials present on the website. Basically what I would like to do is: after the RPi 3 checks if the sensor value matches the correct number, it should send either a 0 if there’s no match or 1 if there’s a match, back to the Losant API. How can I retrieve this value and what http request would I use in my web app? I would really appreciate an example or some directions on how to go about this. Thank you so much in advance!


#2

What is the sensor and how are you reading the data off of it now? If it’s a Python script, you could use our Python SDK to send the data to Losant given the condition you describe. We also have a JavaScript SDK in case you’re reading the data in a Node.js application.

As for reading the data, there are a number of ways you could do that:

If you can provide more specifics about your particular use case, I may be of more help.


#3

Thank you for your prompt reply! So for the application I have an NFC reader module connected to RPi 3, and I want it to just check the NFC cards and check whether the values match some pre defined values. If the UID matches, the script outputs a 1 but if it doesn’t then it outputs a 0. So far I have implemented the workflows in Losant to control the GPIO pins on the RPi from a web application on a smartphone using an HTTP GET request. Now I just want the web application to retrieve whether the RPi’s NFC reader outputs a 0 or 1 when scanning an NFC card. What do you think is the best direction to go with this?


#4

If I’m understanding your setup correctly, then I would suggest you register the RPi as a device in your Losant application, and give it a single attribute (call it “nfcReading”) of the type Number (or boolean if you prefer).

Then, every time your script on the Pi outputs a 1 or a 0, send that state to Losant through our REST API (or one of the clients I mentioned previously).

Finally, when you wish to retrieve that value in your web application, you can retrieve it not from the Pi itself, but from the Losant platform – again, using our API directly or through one of our client libraries.

Let me know if this helps!