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Our recommended approach is to set an MQTT Engine custom namespace to parse the payload as a STRING and then use the Ignition scripting capabilities to parse out the required elements of the text string and write a Fully Qualified Value to a tag in a non managed tag provider.

Let say we have a publish received on the topic "test/data/point" with a payload "28;2023-07-11;16:09:33" . where the payload includes a value and timestamp.

MQTT Engine will create a two folders "test" and "data" and a tag "point" with the value of "28;2023-07-11;16:09:33".

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Code Block

language	py

from com.inductiveautomation.ignition.common.model.values import BasicQualifiedValue, QualityCode
from datetime import datetime

def convertString(string):
    value = int(string.split(";")[0])
    year = int(string.split(";")[1].split("-")[0])
    month = int(string.split(";")[1].split("-")[1])
    day = int(string.split(";")[1].split("-")[2])
    hours = int(string.split(";")[2].split(":")[0])
    mins = int(string.split(";")[2].split(":")[1])
    seconds = int(string.split(";")[2].split(":")[2])
    
    date = system.date.getDate(year,month-1,day)
    datedatetime = system.date.setTime(date,hours, mins, seconds)

    return value, datedatetime


#parse MQTT Engine string tag
path = "[MQTT Engine]test/data/point"
value,timestamp = convertString(system.tag.readBlocking([path])[0].value)

#set quality
quality = QualityCode.Good

#set Basic Qualified Value
bqv = BasicQualifiedValue(value,quality,timestamp)

#set new tag path
newpath = "[MQTT Tags]test/data/point"

#write Basic Qualified Value
system.tag.writeBlocking(newpath,bqv)

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