# Formatting MQTT-output
**URL:** https://community.influxdata.com/t/formatting-mqtt-output/32110
**Category:** Systems
**Tags:** telegraf
**Created:** [November 11, 2023, 1:17pm UTC](https://community.influxdata.com/t/formatting-mqtt-output/32110 "2023-11-11T13:17:23Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Koenraad](https://community.influxdata.com/u/Koenraad)
#### Post date: [November 11, 2023, 1:17pm UTC](https://community.influxdata.com/t/formatting-mqtt-output/32110/1 "2023-11-11T13:17:23Z")
Hi,
Rather new with telegraf and I’m having a problem.
I’m reading data from modbus, that’s OK.
My problem is that I need some of that data sent to MQTT in JSON-format. That works, but only partially.
The data I need to send to MQTT is like this :
```auto
{
"Pac" : 175.0,
"E-Total" : 40834.27
}
```
What I succeeded to do is this :
```auto
{
"fields" : {
"E-Total" : 58343,
"Pac" : 330
},
"name" : "modbus",
"tags" : {
"dc" : "server1",
"host" : "server1",
"name" : "SMA-inverter1",
"slave_id" : "3",
"type" : "holding_register"
},
"timestamp" : 1699707510
}
```
The device that is subscribed to the topic can’t handle this.
How do I remove those “superfluous” items ?
I tried using `layout = "field"`, but then, the data is not JSON-formatted, it’s just two new topics.
I was suggested to read [this](https://community.influxdata.com/t/problems-with-json-transformation-in-telegraf-outputs-mqtt/31751). Is that the way to go ? If yes, where can I find the documentation (plugins ?) ?
Thanks.
---
### Author:  [@Koenraad](https://community.influxdata.com/u/Koenraad)
#### Post date: [November 11, 2023, 2:02pm UTC](https://community.influxdata.com/t/formatting-mqtt-output/32110/2 "2023-11-11T14:02:51Z")
Replying to my own post 🥶
After reading/searching more I found this :
```auto
json_transformation = '''
$merge([fields])
'''
```
Now it works.
---
### Author:  [@Anaisdg](https://community.influxdata.com/u/Anaisdg)
#### Post date: [November 16, 2023, 7:49am UTC](https://community.influxdata.com/t/formatting-mqtt-output/32110/3 "2023-11-16T07:49:06Z")
Hello @Koenraad,
Thank you for including a solution to your answer!