Operator: do
The synchronous version of actuator() api. The actSync function does not take a callback function as argument. Its return value will be injected to signal’s __result__ field.
Signature
NS.do(comment : string, inputs : map, outputs : map, actSync : function) : Node
Arguments
| Arguement | Type | Description |
|---|---|---|
| comment | string | optional, the comment of the actuator |
| inputs | map | optional, the input description |
| outputs | map | optional, the output description |
| actSync | function | optional, the act function, it throws Error or returns the result. If an error is threw, an error signal will be sent, otherwise, the return value will be injected to the signal as __result__ field |
actSync function signature:
function actSync(signal : Signal) : any
If error is threw, an ERROR signal is sent to stream, otherwise the return value is injected to the signal with a special name : __result__. You can access it with signal.getResult()
Return
| Type | Description |
|---|---|
| Node | the actuator node |
Create a sync actuator
const ns = collar.ns('collarjs.demo.actuatorSync');
const input = ns.input('input');
input
.do("print data", signal => { // print signal data
console.log(signal.get("data"));
});
input.push({data : "Hello World"});