Json Custom Parsing Assist

Ignition
1

Hi There,

I need some guidance as to whether the following is even possible. - We have a system where we get the following JSON message:
{
"type" : "DeviceCommand",
"sessionId" : "86a624c5-fa85-4e82-8c5b-0c09774139a3",
"controllerId" : "PLC_NAME",
"devices" : [ {
"moduleType" : "Custom",
"deviceId" : "g_ASOUTBOUNDPORT220READY",
"command" : ""
} ]
}

The INTENT of the message is to request the current value of "g_ASOUTBOUNDPORT220READY" from "PLC_NAME" (which can be any of a number of PLC's connected to Ignition)

The EXPECTED response message we need to generate SHOULD look like:
{
"type" : "DeviceStatus",
"sessionId" : "86a624c5-fa85-4e82-8c5b-0c09774139a3",
"controllerId" : "PLC_NAME",
"devices" : [ {
"moduleType" : "Custom",
"deviceId" : "g_ASOUTBOUNDPORT220READY",
"command" : "TRUE"
} ]
}

Thank You for any feedback

2

How is this message delivered? Are you using the WebDev module to handle an incoming API request? WebDev will handle json for you, converting to/from jython dictionaries and lists.

3

Hi Phil,

We were actually doing this using CirrusLink MQTT and connection to an AMQ (Apache) server that acts like the broker. So the "interfacing" was done via that. - THere was some scripting around "message received / populate response / send the response" items.

However we have since started looking at the WebDev module (still learning) and are busy exploring this. - We are at this moment still thinking to "subscribe" to the AMQ topics and process replies to the relevant "return topic".