# Developing Nodes **URL:** https://discourse.nodered.org/c/developing-nodes/15.md?page=33 [Latest](https://discourse.nodered.org/latest.md) · [Categories](https://discourse.nodered.org/categories.md) · [Tags](https://discourse.nodered.org/tags.md) **Page:** 34 --- ## [Help with creating a new node with c++](https://discourse.nodered.org/t/help-with-creating-a-new-node-with-c/41713)
**Author:** [@theo481](https://discourse.nodered.org/u/theo481)\ **Replies:** 3\ **Last updated:** [27 February 2021 14:09 UTC](https://discourse.nodered.org/t/help-with-creating-a-new-node-with-c/41713 "2021-02-27T14:09:36Z")
Hi everyone, Still being quite new ( with node-red, node.js and javascript in general) so understanding code online is not easy; I was therefore hoping to find some help over her. I wrote some code in c++, that I manag… --- ## [Creating custom node and the getting accesstoken and then making api call on single custom node](https://discourse.nodered.org/t/creating-custom-node-and-the-getting-accesstoken-and-then-making-api-call-on-single-custom-node/41605)
**Author:** [@Sudthakur](https://discourse.nodered.org/u/Sudthakur)\ **Replies:** 4\ **Last updated:** [26 February 2021 21:14 UTC](https://discourse.nodered.org/t/creating-custom-node-and-the-getting-accesstoken-and-then-making-api-call-on-single-custom-node/41605 "2021-02-26T21:14:46Z")
Hello, I created the custom node called getMachines where I will be supplying the ClientId and ClientSecret in input of the node. And after that i will be accessing the accessToken to get the API data. After that on … --- ## [Custom node-red logger- show line numbers](https://discourse.nodered.org/t/custom-node-red-logger-show-line-numbers/17924)
**Author:** [@uma](https://discourse.nodered.org/u/uma)\ **Replies:** 8\ **Last updated:** [25 February 2021 12:08 UTC](https://discourse.nodered.org/t/custom-node-red-logger-show-line-numbers/17924 "2021-02-25T12:08:49Z")
Hi I am trying to debug an error in my custom node. I get something like this in the console: 14 Nov 16:28:44 - \[error\] \[test-validation:d5746feb.8c06d\] TypeError: Cannot read property 'undefined' of undefined Though… --- ## [Add Docs on VS Code to debug Node-RED and nodes](https://discourse.nodered.org/t/add-docs-on-vs-code-to-debug-node-red-and-nodes/11891)
**Author:** [@tree-frog](https://discourse.nodered.org/u/tree-frog)\ **Replies:** 13\ **Last updated:** [24 February 2021 18:17 UTC](https://discourse.nodered.org/t/add-docs-on-vs-code-to-debug-node-red-and-nodes/11891 "2021-02-24T18:17:34Z")
For those who are beginning Node-RED and running into some problems with particular nodes, Can someone please post a typical configuration in order to run Node-RED in VS Code in order to facilitate finding problems with… --- ## [Missing node error on "npm install" of custom node](https://discourse.nodered.org/t/missing-node-error-on-npm-install-of-custom-node/41309)
**Author:** [@jtaylor](https://discourse.nodered.org/u/jtaylor)\ **Replies:** 15\ **Last updated:** [24 February 2021 07:16 UTC](https://discourse.nodered.org/t/missing-node-error-on-npm-install-of-custom-node/41309 "2021-02-24T07:16:42Z")
When I do an npm command to install/update a custom node, I'm getting an error regarding a missing node. I created and installed the sample red-contrib-example-lower-case node. I have subsequently removed that node, bu… --- ## [forwardInputMessages in UI node](https://discourse.nodered.org/t/forwardinputmessages-in-ui-node/41513)
**Author:** [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\ **Replies:** 7\ **Last updated:** [23 February 2021 22:21 UTC](https://discourse.nodered.org/t/forwardinputmessages-in-ui-node/41513 "2021-02-23T22:21:30Z")
Hi folks, I'm wondering how forwardInputMessages in a UI node works. The dashboard Switch-node has following setting: By looking at the Switch-node (code), it is being used like this: forwardInputMessages: config.p… --- ## [Node-Red don´t set node properties default values on load](https://discourse.nodered.org/t/node-red-don-t-set-node-properties-default-values-on-load/41343)
**Author:** [@iiot2k](https://discourse.nodered.org/u/iiot2k)\ **Replies:** 8\ **Last updated:** [21 February 2021 11:56 UTC](https://discourse.nodered.org/t/node-red-don-t-set-node-properties-default-values-on-load/41343 "2021-02-21T11:56:39Z")
I have a question to Node properties default value: My frist version of node html file: defaults: { val1: { value: 10, required: true, validate: RED.validators.number() }, }, I add new node propert… --- ## [Filtering a config object within a node that uses it](https://discourse.nodered.org/t/filtering-a-config-object-within-a-node-that-uses-it/41357)
**Author:** [@Achronite](https://discourse.nodered.org/u/Achronite)\ **Replies:** 3\ **Last updated:** [21 February 2021 10:25 UTC](https://discourse.nodered.org/t/filtering-a-config-object-within-a-node-that-uses-it/41357 "2021-02-21T10:25:07Z")
I have a config object that is used to store/select a list of different types of IoT devices. I also have a set of specific nodes for each type of IoT device I would like to know, is it possible to filter the devices d… --- ## [Modify the node instance definition from the runtime?](https://discourse.nodered.org/t/modify-the-node-instance-definition-from-the-runtime/41274)
**Author:** [@zachowj](https://discourse.nodered.org/u/zachowj)\ **Replies:** 4\ **Last updated:** [19 February 2021 21:07 UTC](https://discourse.nodered.org/t/modify-the-node-instance-definition-from-the-runtime/41274 "2021-02-19T21:07:27Z")
Can you update the values of a node instance from the runtime? I am looking to run data migration on existing nodes when they are loaded. --- ## [Data-template and data-help script type: text/x-red or text/html?](https://discourse.nodered.org/t/data-template-and-data-help-script-type-text-x-red-or-text-html/41256)
**Author:** [@drmibell](https://discourse.nodered.org/u/drmibell)\ **Replies:** 1\ **Last updated:** [18 February 2021 18:43 UTC](https://discourse.nodered.org/t/data-template-and-data-help-script-type-text-x-red-or-text-html/41256 "2021-02-18T18:43:50Z")
Some time ago (I can't remember exactly), the recommended type for these scripts was changed from text/x-red to text/html. Should I bother to go back and change my older nodes? Will this matter in the future? --- ## [Clear configuration node property/flow json properties](https://discourse.nodered.org/t/clear-configuration-node-property-flow-json-properties/40455)
**Author:** [@justin](https://discourse.nodered.org/u/justin)\ **Replies:** 2\ **Last updated:** [18 February 2021 15:19 UTC](https://discourse.nodered.org/t/clear-configuration-node-property-flow-json-properties/40455 "2021-02-18T15:19:14Z")
I have created some custom nodes that are used to connect to other servers, proxies, etc. All that works fine but what bothers me is that if a user inputs an api key/secret values into the configuration server form, thos… --- ## [Is a ds3231 rtc Node-Red node useful?](https://discourse.nodered.org/t/is-a-ds3231-rtc-node-red-node-useful/41124)
**Author:** [@iiot2k](https://discourse.nodered.org/u/iiot2k)\ **Replies:** 7\ **Last updated:** [17 February 2021 16:27 UTC](https://discourse.nodered.org/t/is-a-ds3231-rtc-node-red-node-useful/41124 "2021-02-17T16:27:44Z")
I have got a ds3231 rtc module. When I look in Node-Red nodes library, there isn´t a ds3231 node. The system time on Raspberry pi is set by ntp server. If internet isn´t avaible, you can configure hwclock for time bac… --- ## [Aqara Oppel Switch (3 keys) - node](https://discourse.nodered.org/t/aqara-oppel-switch-3-keys-node/40861)
**Author:** [@tomg1970](https://discourse.nodered.org/u/tomg1970)\ **Replies:** 2\ **Last updated:** [17 February 2021 12:01 UTC](https://discourse.nodered.org/t/aqara-oppel-switch-3-keys-node/40861 "2021-02-17T12:01:59Z")
First of all, I want to say "Hello" here. I have a node-red problem. I need a control for "Aqara Oppel 3gang switch" which Buttons. It is best to switch this on / off in the "Toogle" function (device on IoBroker) o… --- ## [Knx-ultimate to UDP-out](https://discourse.nodered.org/t/knx-ultimate-to-udp-out/41097)
**Author:** [@ewgeo](https://discourse.nodered.org/u/ewgeo)\ **Replies:** 4\ **Last updated:** [17 February 2021 10:44 UTC](https://discourse.nodered.org/t/knx-ultimate-to-udp-out/41097 "2021-02-17T10:44:47Z")
I installed KNX-Ultimate and inserted my ESF File from ETS5 (the CSV did not work). In the debug flow with complete msg I can see all I need. I want to send all data to an UDP-Out Flow and there I always can send only on… --- ## [Node for communicating with Stellar Blockchain](https://discourse.nodered.org/t/node-for-communicating-with-stellar-blockchain/41131)
**Author:** [@BlockShangerous](https://discourse.nodered.org/u/BlockShangerous)\ **Replies:** 0\ **Last updated:** [17 February 2021 00:52 UTC](https://discourse.nodered.org/t/node-for-communicating-with-stellar-blockchain/41131 "2021-02-17T00:52:42Z")
I am new to node red and trying to use it to communicate with the Stellar Blockchain. Stellar already has an existing JS SDK So I am wondering what the best way to go about this is? I have tried following tutorials wi… --- ## [More ways to provide help for your custom node](https://discourse.nodered.org/t/more-ways-to-provide-help-for-your-custom-node/41127)
**Author:** [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\ **Replies:** 0\ **Last updated:** [17 February 2021 00:03 UTC](https://discourse.nodered.org/t/more-ways-to-provide-help-for-your-custom-node/41127 "2021-02-17T00:03:27Z")
Just wanted to share a quick tip for people writing custom nodes, especially if the are getting a bit more complex and needing more help space than is convenient in the Node-RED info panel. uibuilder is now getting quit… --- ## [How to create dashboard node for toast popups?](https://discourse.nodered.org/t/how-to-create-dashboard-node-for-toast-popups/41090)
**Author:** [@clickworkorange](https://discourse.nodered.org/u/clickworkorange)\ **Replies:** 4\ **Last updated:** [16 February 2021 14:01 UTC](https://discourse.nodered.org/t/how-to-create-dashboard-node-for-toast-popups/41090 "2021-02-16T14:01:54Z")
Trying to build a simple node to show "mdToast" popups on incoming messages. Looking at the existing "Notification" node I see it uses ui.add to insert itself, and not ui.addWidget (like "normal" widgets which belong to … --- ## [Best Practice to import an ES6 Module in a node for Node-RED](https://discourse.nodered.org/t/best-practice-to-import-an-es6-module-in-a-node-for-node-red/41014)
**Author:** [@chunyianliew](https://discourse.nodered.org/u/chunyianliew)\ **Replies:** 2\ **Last updated:** [15 February 2021 15:44 UTC](https://discourse.nodered.org/t/best-practice-to-import-an-es6-module-in-a-node-for-node-red/41014 "2021-02-15T15:44:57Z")
I am looking for the best practice to import an ES6 module in a node for Node-Red. I would appreciate it if someone can provide me with some guidance here. Here is some additional background information: There is an li… --- ## [Web Relay Dual Control 8in/8out Ethernet RJ45](https://discourse.nodered.org/t/web-relay-dual-control-8in-8out-ethernet-rj45/40658)
**Author:** [@Baxe](https://discourse.nodered.org/u/Baxe)\ **Replies:** 21\ **Last updated:** [14 February 2021 19:25 UTC](https://discourse.nodered.org/t/web-relay-dual-control-8in-8out-ethernet-rj45/40658 "2021-02-14T19:25:49Z")
Hi, know nothing about Node red , but would like to get so you could control this relay via NodRed, send with some instructions ... Relay on Ebay On this forum they get it to work Loxforum --- ## [Syntax command control nextion display](https://discourse.nodered.org/t/syntax-command-control-nextion-display/40936)
**Author:** [@pinie\_pinie](https://discourse.nodered.org/u/pinie_pinie)\ **Replies:** 10\ **Last updated:** [13 February 2021 17:56 UTC](https://discourse.nodered.org/t/syntax-command-control-nextion-display/40936 "2021-02-13T17:56:12Z")
Hi, I would like to control a text field in a Nextion display with a variable text. The command must be at the end: NEXTION, t1.txt = "Hello" "Hello" should correspond to the payload. But it is imperative that the Qu… --- ## [Help from model and robot making professionals](https://discourse.nodered.org/t/help-from-model-and-robot-making-professionals/40881)
**Author:** [@iiot2k](https://discourse.nodered.org/u/iiot2k)\ **Replies:** 4\ **Last updated:** [12 February 2021 21:56 UTC](https://discourse.nodered.org/t/help-from-model-and-robot-making-professionals/40881 "2021-02-12T21:56:43Z")
Hi, I start to write two nodes for pca9685 pwm chip. One node is for normal pwm output. And other one is special for robot and model making hobbist. My question is how control the servos on pca9685 output. I read on… --- ## [Can you check the number of active nodes connected to the current node?](https://discourse.nodered.org/t/can-you-check-the-number-of-active-nodes-connected-to-the-current-node/40871)
**Author:** [@Norberg95](https://discourse.nodered.org/u/Norberg95)\ **Replies:** 1\ **Last updated:** [12 February 2021 18:30 UTC](https://discourse.nodered.org/t/can-you-check-the-number-of-active-nodes-connected-to-the-current-node/40871 "2021-02-12T18:30:26Z")
I would like to check the number of connected enabled (or disabled) nodes to to current node ONLY on the input. Possibly to check the type of node connected. --- ## [Read and Write .dat files](https://discourse.nodered.org/t/read-and-write-dat-files/40774)
**Author:** [@hederson2801](https://discourse.nodered.org/u/hederson2801)\ **Replies:** 6\ **Last updated:** [12 February 2021 17:04 UTC](https://discourse.nodered.org/t/read-and-write-dat-files/40774 "2021-02-12T17:04:00Z")
Hello guys, I need to read and write information in the .dat file. This file has a programming in C language. In it I have variables and logic. I would like to know if there is a way to read this file from a location on … --- ## [Thermostat in function node](https://discourse.nodered.org/t/thermostat-in-function-node/40577)
**Author:** [@lundig](https://discourse.nodered.org/u/lundig)\ **Replies:** 16\ **Last updated:** [11 February 2021 20:52 UTC](https://discourse.nodered.org/t/thermostat-in-function-node/40577 "2021-02-11T20:52:34Z")
Hello, Let me start with informing that i am a supernoob in programming JSON. I am trying to setup a thermostat function in node-red. The idea is to control my heatpump´s temperature, and fanspeed settings based on a … --- ## [Node.send direct/broadcast to LinkIn type of receiver instead of port out](https://discourse.nodered.org/t/node-send-direct-broadcast-to-linkin-type-of-receiver-instead-of-port-out/40786)
**Author:** [@justin](https://discourse.nodered.org/u/justin)\ **Replies:** 0\ **Last updated:** [10 February 2021 22:14 UTC](https://discourse.nodered.org/t/node-send-direct-broadcast-to-linkin-type-of-receiver-instead-of-port-out/40786 "2021-02-10T22:14:49Z")
Is it possible to pass a callback into a node that redirects the port out to another node (like a IinkIn event receiver)? I don't mean create a LinkOut that takes the message from the node, or a switch that routes it exp… --- ## [Creation of Catalog](https://discourse.nodered.org/t/creation-of-catalog/9722)
**Author:** [@Devbrat](https://discourse.nodered.org/u/Devbrat)\ **Replies:** 25\ **Last updated:** [8 February 2021 15:53 UTC](https://discourse.nodered.org/t/creation-of-catalog/9722 "2021-02-08T15:53:19Z")
Hi all, I have developed one repository for nodes, For that, I also wanted to allow the user to install via palette manager in Node-RED. To Do so I followed below link to add catalog. But I do not have any Idea about… --- ## [Question about Function Node and Topic syntax](https://discourse.nodered.org/t/question-about-function-node-and-topic-syntax/40274)
**Author:** [@Trinican](https://discourse.nodered.org/u/Trinican)\ **Replies:** 13\ **Last updated:** [6 February 2021 16:24 UTC](https://discourse.nodered.org/t/question-about-function-node-and-topic-syntax/40274 "2021-02-06T16:24:15Z")
This is my first post on this forum and I am very new to Node Red. It seems very exciting and I have already developed a very nice home automation application which has encouraged me to explore and develop more complex … --- ## [Units Testing on a Node](https://discourse.nodered.org/t/units-testing-on-a-node/40359)
**Author:** [@jeevan900929](https://discourse.nodered.org/u/jeevan900929)\ **Replies:** 6\ **Last updated:** [4 February 2021 13:17 UTC](https://discourse.nodered.org/t/units-testing-on-a-node/40359 "2021-02-04T13:17:29Z")
Hi, How does one set a configuration node values in a unit test? Thank you --- ## [Node Button Event](https://discourse.nodered.org/t/node-button-event/40313)
**Author:** [@jeevan900929](https://discourse.nodered.org/u/jeevan900929)\ **Replies:** 6\ **Last updated:** [4 February 2021 10:19 UTC](https://discourse.nodered.org/t/node-button-event/40313 "2021-02-04T10:19:24Z")
I have a node with a button that has an onClick event \