Message Payload Limitations

[ghayne]

In a change node try JSONata using $substring().

Like this:

[
    {
        "id": "65f4413785b287b6",
        "type": "change",
        "z": "2f55b30644be1197",
        "name": "",
        "rules": [
            {
                "t": "set",
                "p": "payload",
                "pt": "msg",
                "to": "$substring(payload, start, length)",
                "tot": "jsonata"
            }
        ],
        "action": "",
        "property": "",
        "from": "",
        "to": "",
        "reg": false,
        "x": 340,
        "y": 240,
        "wires": [
            []
        ]
    }
]

The "Length" parameter is optional!

[StevenMurray2022]

Hi Garry,

Do I just put the start and length values to say 7 and 160 to miss out the first 6 characters?

[ghayne]

Start would be 6! first element is 0. omit the length, you'll get the rest of the string

$substring(payload,6)

Should do it!

[StevenMurray2022]

@ghayne

[
    {
        "id": "2f55b30644be1197",
        "type": "tab",
        "label": "Flow 2",
        "disabled": false,
        "info": "",
        "env": []
    },
    {
        "id": "10b71daa4f1b1bb0",
        "type": "inject",
        "z": "2f55b30644be1197",
        "name": "",
        "props": [
            {
                "p": "payload"
            }
        ],
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "topic": "",
        "payload": "Message1",
        "payloadType": "str",
        "x": 100,
        "y": 100,
        "wires": [
            [
                "9e773d118fa24bdc"
            ]
        ]
    },
    {
        "id": "9e773d118fa24bdc",
        "type": "join",
        "z": "2f55b30644be1197",
        "name": "",
        "mode": "custom",
        "build": "string",
        "property": "payload",
        "propertyType": "msg",
        "key": "topic",
        "joiner": "",
        "joinerType": "str",
        "accumulate": false,
        "timeout": "",
        "count": "2",
        "reduceRight": false,
        "reduceExp": "",
        "reduceInit": "",
        "reduceInitType": "",
        "reduceFixup": "",
        "x": 330,
        "y": 100,
        "wires": [
            [
                "521b3db1a5d220e2"
            ]
        ]
    },
    {
        "id": "fbe2a05264d45f1f",
        "type": "inject",
        "z": "2f55b30644be1197",
        "name": "",
        "props": [
            {
                "p": "payload"
            }
        ],
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "topic": "",
        "payload": "Message2",
        "payloadType": "str",
        "x": 100,
        "y": 140,
        "wires": [
            [
                "9e773d118fa24bdc"
            ]
        ]
    },
    {
        "id": "521b3db1a5d220e2",
        "type": "debug",
        "z": "2f55b30644be1197",
        "name": "",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "false",
        "statusVal": "",
        "statusType": "auto",
        "x": 610,
        "y": 100,
        "wires": []
    }
]

That's it. Thanks Garry.