# Parsing an MQTT message in rules

**URL:** <https://community.openhab.org/t/parsing-an-mqtt-message-in-rules/98119>\
**Category:** Off-Topic\
**Tags:** beginners\
**Created:** [May 4, 2020, 6:18pm UTC](https://community.openhab.org/t/parsing-an-mqtt-message-in-rules/98119 "2020-05-04T18:18:38Z")\
**Posts on this page:** 1\
**Showing post:** 12

<div class="post-metadata">

**Author:** ![JimH](https://community.openhab.org/letter_avatar_proxy/v4/letter/j/a4c791/32.png) [@JimH](https://community.openhab.org/u/JimH)\
**Post date:** [May 6, 2020, 9:05pm UTC](https://community.openhab.org/t/parsing-an-mqtt-message-in-rules/98119/12 "2020-05-06T21:05:12Z")

</div>

> [@Alan\_79](#):
>
> figure out how checkKthBit is going to work

Once you have the value stored in an integer you might want to implement something like this in the rule instead of checkKthBit.

Items:

```csv
Switch Port8 "Port 8" 
Switch Port7 "Port 7" 
Switch Port6 "Port 6" 
Switch Port5 "Port 5" 
Switch Port4 "Port 4"   
Switch Port3 "Port 3" 
Switch Port2 "Port 2" 
Switch Port1 "Port 1"

```

Rule:

```php
// AllBits must be defined as an integer. The value from MQTT will be store here
var Integer AllBits  

when ???? changed 
then
    // Place the value from the REGEX in AllBits (possibly converting to an integer beforehand)
    
    if (AllBits >= 128 ) {
        Port8.postUpdate(ON)
        AllBits = AllBits - 128
    }
    else {
        Port8.postUpdate(OFF)
    }
    if (AllBits >= 64 ) {
        Port7.postUpdate(ON)
        AllBits = AllBits - 64
    }
    else {
        Port7.postUpdate(OFF)
    }
    if (AllBits >= 32 ) {
        Port6.postUpdate(ON)
        AllBits = AllBits - 32
    }
    else {
        Port6.postUpdate(OFF)
    }
    }if (AllBits >= 16 ) {
        Port5.postUpdate(ON)
        AllBits = AllBits - 16
    }
    else {
        Port5.postUpdate(OFF)
    }
    if (AllBits >= 8 ) {
        Port4.postUpdate(ON)
        AllBits = AllBits - 8
    }
    else {
        Port4.postUpdate(OFF)
    }
    if (AllBits >= 4 ) {
        Port3.postUpdate(ON)
        AllBits = AllBits - 4
    }
    else {
        Port3.postUpdate(OFF)
    }
    if (AllBits >= 2 ) {
        Port2.postUpdate(ON)
        AllBits = AllBits - 2
    }
    else {
        Port2.postUpdate(OFF)
    }
    if (AllBits >= 1 ) {
        Port1.postUpdate(ON)
        AllBits = AllBits - 1
    }
    else {
        Port1.postUpdate(OFF)
    }
end

```

I haven’t tested this but VSC shows no syntax errors. Its not as elegant as checkKthBit but easier to understand (IMO)

---

_[View the full topic](https://community.openhab.org/t/parsing-an-mqtt-message-in-rules/98119)._