Static data from SignalK

[kniven]

Hi all. I'm using the node-red  embedded in signalK.  All good. 
I will now try to experiment with/create an alternative "navigation Autopilot", following  a route with waypoints. Hopefully somewhat better than the OpenCPN version, which has a tendency to "cut corners" when approaching a waypoint. 
I will need (for now) three parameters to work with. Current position (updating 1Hz) , as well as two waypoints along the route (next, previous). 
For retrieving these input data I have installed the node-red-contrib-signalk v1.2.0

My initial problem is that the two (quasi) static WP are not updating in signalK, and the signalk-subscribe block in node-red only receives messages when the values change. The current position streams nicely into my stream, but the two waypoints do not even receive their initial value (apparently).

So my question is: In node-red; Is there a way to request the current value for all of these inputs, irrespective of whether they are changing or not?

Or alternatively. Is there a more clever way to handle tis in node-red? My only requirement is synchronized sets of the three positions, that I can send into my Python block for further processing...

Thanks in advance.
Leif

[saltwaterone]

Hi all. I'm using the node-red  embedded in signalK.  All good. 
I will now try to experiment with/create an alternative "navigation Autopilot", following  a route with waypoints. Hopefully somewhat better than the OpenCPN version, which has a tendency to "cut corners" when approaching a waypoint. 
I will need (for now) three parameters to work with. Current position (updating 1Hz) , as well as two waypoints along the route (next, previous). 
For retrieving these input data I have installed the node-red-contrib-signalk v1.2.0

My initial problem is that the two (quasi) static WP are not updating in signalK, and the signalk-subscribe block in node-red only receives messages when the values change. The current position streams nicely into my stream, but the two waypoints do not even receive their initial value (apparently).

So my question is: In node-red; Is there a way to request the current value for all of these inputs, irrespective of whether they are changing or not?

Or alternatively. Is there a more clever way to handle tis in node-red? My only requirement is synchronized sets of the three positions, that I can send into my Python block for further processing...

Thanks in advance.
Leif

***
Wouldn't the 'on delta' node do exactly that?

[PaddyB]

So my question is: In node-red; Is there a way to request the current value for all of these inputs, irrespective of whether they are changing or not?

This in a function node does that

Code:

let _ = global.get('lodash');
let app = global.get('app');
let radarArchCurrent = app.getSelfPath('electrical.solar.arch.chargingCurrent');
let railsCurrent = app.getSelfPath('electrical.solar.rails.dc.current');
let shuntCurrent = app.getSelfPath('electrical.batteries.house.current');
let houseCurrent =  shuntCurrent.value - railsCurrent.value - radarArchCurrent.value;
msg.rails = railsCurrent;
msg.shunt = shuntCurrent;
msg.arch = radarArchCurrent;
msg.payload = houseCurrent;
msg.topic = "electrical.house.current";
return msg;

For retrieving these input data I have installed the node-red-contrib-signalk v1.2.0 >>
Sounds odd, if you install the node-red signalk app that node should be there already. 

Does the signalk autopilot route plugin do what you want already? I use it with pypilot but just left it at the defaults, prefer the radius it takes round waypoints so not sure if it can steer very tight.