A Node-RED node to create a counter with messages.
npm install node-red-contrib-counternode-red-contrib-counter
========================
A Node-RED node to create a counter with messages.
---
~/.node-red:
npm install node-red-contrib-counter
`
Usage
By default the counter will be incremented for every inbound message and append the current count to msg.count.
$3
- Initial Count: The initial count can be set in the configuration. By default it will be zero at start.
- Default Step: Default amount that will be incremented or decremented on every incoming message.
- Lower Limit: Optional limitation of the lower count limit. Will add countLowerLimitReached to msg if reached.
- Upper Limit: Optional limitation of the upper count limit. Will add countUpperLimitReached to msg if reached.
- Mode: Determine if count value should be incremented or decremented on every incoming message.
- Outputs: Selects the output format of the counter. _For more info read below._
$3
There are two output options for the counter value:
- single: The actual count will be appended to msg.count of the original msg.
- split: The node will become two outputs, first will return the count as msg.payload and possible limitation info, the second returns the untouched original msg.
$3
It's possible to control the counter with incoming msg properties:
- msg.increment: counter will be incremented by the given value.
- msg.decrement: counter will be decremented by the given value.
- msg.reset: resets the counter to it's initial count, or to the given value, when it's a number.
Example Flows
Simple example showing how to use the counter and it's output.
!example1.png
`JSON
[{"id":"25b6280d.1ecf6","type":"inject","z":"327d23e5.bb5924","name":"decrement","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":380,"y":160,"wires":[["8a41c1.6006b64"]]},{"id":"285e0e19.b9680a","type":"inject","z":"327d23e5.bb5924","name":"increment","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":380,"y":120,"wires":[["ce8d952f.18666"]]},{"id":"fda0a334.bc9588","type":"inject","z":"327d23e5.bb5924","name":"reset","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":370,"y":200,"wires":[["17cce981.975686"]]},{"id":"ce8d952f.18666","type":"function","z":"327d23e5.bb5924","name":"msg object","func":"msg.increment = 2;\nreturn msg;","outputs":1,"noerr":0,"x":550,"y":120,"wires":[["ac65bf94.6e609"]]},{"id":"17cce981.975686","type":"function","z":"327d23e5.bb5924","name":"msg object","func":"msg.reset = true;\nreturn msg;","outputs":1,"noerr":0,"x":550,"y":200,"wires":[["ac65bf94.6e609"]]},{"id":"8a41c1.6006b64","type":"function","z":"327d23e5.bb5924","name":"msg object","func":"msg.decrement = 1;\nreturn msg;","outputs":1,"noerr":0,"x":550,"y":160,"wires":[["ac65bf94.6e609"]]},{"id":"ac65bf94.6e609","type":"counter","z":"327d23e5.bb5924","name":"","init":"0","step":1,"lower":null,"upper":null,"mode":"increment","outputs":"1","x":740,"y":140,"wires":[["988afc3c.a08f98"]]},{"id":"370626a8.22216a","type":"inject","z":"327d23e5.bb5924","name":"normal msg without control parameter","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":470,"y":80,"wires":[["ac65bf94.6e609"]]},{"id":"988afc3c.a08f98","type":"debug","z":"327d23e5.bb5924","name":"message","active":true,"console":"false","complete":"true","x":900,"y":140,"wires":[]}]
`
!example2.png
`JSON
[{"id":"4f41c5a1.85426c","type":"inject","z":"327d23e5.bb5924","name":"decrement","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":380,"y":380,"wires":[["e9085587.2d19c"]]},{"id":"afb267a8.63739","type":"inject","z":"327d23e5.bb5924","name":"increment","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":380,"y":340,"wires":[["4a35e3c7.3dbd0c"]]},{"id":"f066adf1.21ba","type":"inject","z":"327d23e5.bb5924","name":"reset","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":370,"y":420,"wires":[["523f8e05.d5537"]]},{"id":"4a35e3c7.3dbd0c","type":"function","z":"327d23e5.bb5924","name":"msg object","func":"msg.increment = 3;\nreturn msg;","outputs":1,"noerr":0,"x":550,"y":340,"wires":[["f33ad4bd.777a5"]]},{"id":"523f8e05.d5537","type":"function","z":"327d23e5.bb5924","name":"msg object","func":"msg.reset = 10;\nreturn msg;","outputs":1,"noerr":0,"x":550,"y":420,"wires":[["f33ad4bd.777a5"]]},{"id":"e9085587.2d19c","type":"function","z":"327d23e5.bb5924","name":"msg object","func":"msg.decrement = 1;\nreturn msg;","outputs":1,"noerr":0,"x":550,"y":380,"wires":[["f33ad4bd.777a5"]]},{"id":"9b40b088.73732","type":"debug","z":"327d23e5.bb5924","name":"count","active":true,"console":"false","complete":"payload","x":890,"y":340,"wires":[]},{"id":"f33ad4bd.777a5","type":"counter","z":"327d23e5.bb5924","name":"","init":"100","step":"1","lower":null,"upper":null,"mode":"increment","outputs":"2","x":740,"y":360,"wires":[["9b40b088.73732"],["876cc69d.d4b438"]]},{"id":"99b73d63.9fdb","type":"inject","z":"327d23e5.bb5924","name":"normal msg without control parameter","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"x":470,"y":300,"wires":[["f33ad4bd.777a5"]]},{"id":"876cc69d.d4b438","type":"debug","z":"327d23e5.bb5924","name":"message","active":false,"console":"false","complete":"true","x":900,"y":380,"wires":[]}]
``