Parsing sensor data to a JSON file through MQTT Broker

Question

Hi Dev team, 
 I am working on a nrf9160DK and transmitting my sensor data to a MQTT Client. I tested this through an application : MQTT.fx (Using mqtt.eclipse.org as open source broker) and I was able to get my data published. 
 Now, I need to parse my sensor data to a JSON file using the same broker : mqtt.eclipse.org on topic : my/publish/topic. 
 I have attached the JSON file where my data needs to be passed. 
 8867.config.rar 
 I would like to know the steps that would be required to parse data from my code to a JSON file. 
 I used the mqtt_simple client example in NCS v1.3.0 to publish the data outside. Can it be modified to parse the data to a JSON file. 
 Regards, 
 Adeel.

JONATHAN LL · Accepted Answer

Hi Addel, There si no need send the broker info in JSON format. The MQTT example is setting up a MQTT client on the nrf9160 much like the MQTT.fx does on your computer. First the client tries to connect to the server(broker), and when it achieves a connection it will subscribe to a topic (my/publish/topic). Then there is no need to send the broker port and topic together with the message(sensor data). You can do it but since it the broker and topic info is all ready known it should be no use to send it as well. You can also test the mqtt_simple example with HIVE mqtt websocket . Here is a link to a extra cJSON Devzone case . 
 Adeel said: I also needed to segregate different data in a JSON format like how it is in the attached JSON file and send out. So, I think cJSON library is a good starting point for this 
 Yes, cJSON will work for this. Regards, Jonathan

Parsing sensor data to a JSON file through MQTT Broker

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