Update fact during runtime (OPC UA), then trigger rule evaluation

[mikakaraila]

I would like to use OPC UA and as I got new value I am trying to update fact first.

Then I want to run actual rules. So it will be more event based.

For some reason this snippet does not call actual addFact:

monitoredItemGroup.on("changed", (monitoredItem, dataValue, index) => {
          var tag = items[index].nodeId.toString();
          var val = dataValue.value.value.toString();
          if (dataValue.value.dataType === 10) {
              val = dataValue.value.value.toFixed(2).toString();
          }
          // update facts!!
          console.log("update facts:" + tag + " value: " + val);
          engine.addFact('pump-information', function (params, almanac) {
            console.log('Updating live values...' + JSON.stringify(params) + " " + JSON.stringify(almanac));
            return almanac.factValue('nodeId')
              .then((tag) => {
                console.log("Updating facts for nodeId: " + tag + " value:" + val);
                return { value: val }
              })
          });
      });

[CacheControl]

hey @mikakaraila sorry you're having problems. I wasn't familiar with OPC UA, it looks really neat.

I assume this is on node-red? We did have one issue filed a few years back on node-red, in which the following was mentioned:

Node-Red runs user-supplied code inside a JavaScript VM which upsets json-rules-engine in a few ways. The solution is to use a third-party unsafe code node for rules engine ops.

Any chance that means anything to you? Sorry, I can't be much use here. If you're able to zero in on what's going on, I'm happy to accept a PR.

[mikakaraila]

I am not using node-red, this is just small experiment how to bind real-time data to facts.
I will refactor code and try other way. I will keep you updated as I found a way or propose PR.

[mikakaraila]

I started to read code. Do you have example how to use runtimeFacts?
It is in the Almanac constructor. I suppose I need to turn on also allowUndefined facts.

[mikakaraila]

OK, problem seems to be missing contructor for Almanac.

// Just to make instance is not working (cannot be constructed):
let testFact = new Fact({factId: "ns=1;s=TEST", value:{} });
let almanac = new Almanac( new Map(), testFact, {allowUndefinedFacts: true} );

Usage to update fact value:
// update facts!!
console.log("update facts:" + nodeId + " value: " + value);
almanac.addRuntimeFact({factId: nodeId, value: value});

[mikakaraila]

I took copy and modified code a bit, now I have DYNAMIC facts. Have to study bit more how to use these:

[CacheControl]

Closing due to inactivity