# General

**URL:** https://discourse.nodered.org/c/general/7.md?page=658

[Latest](https://discourse.nodered.org/latest.md) · [Categories](https://discourse.nodered.org/categories.md) · [Tags](https://discourse.nodered.org/tags.md)

**Page:** 659

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## [Passive Notifications from Node-Red Dashboard](https://discourse.nodered.org/t/passive-notifications-from-node-red-dashboard/35396)

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**Author:** [@plefneski](https://discourse.nodered.org/u/plefneski)\
**Replies:** 0\
**Last updated:** [5 November 2020 19:44 UTC](https://discourse.nodered.org/t/passive-notifications-from-node-red-dashboard/35396 "2020-11-05T19:44:20Z")

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I have been trying to create passive notifications from node-red for quite some time now but I am not able to find a way to make it work. I am running on a raspberry pi 4 with buster. I was using the ui dashboard notifi…

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## [While Loop not shutting down](https://discourse.nodered.org/t/while-loop-not-shutting-down/35298)

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**Author:** [@RASelkirk](https://discourse.nodered.org/u/RASelkirk)\
**Replies:** 3\
**Last updated:** [5 November 2020 19:37 UTC](https://discourse.nodered.org/t/while-loop-not-shutting-down/35298 "2020-11-05T19:37:06Z")

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Hi All, Hoping someone will take a look, I'm trying to understand why my "while loop" nodes are acting...odd: \[{"id":"fc2942fb.cd18","type":"group","z":"c199b9b6.017a2","name":"Text Labels","style":{"stroke":"#92d04f",…

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## [Raspberry Pi Desktop Installation](https://discourse.nodered.org/t/raspberry-pi-desktop-installation/14778)

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**Author:** [@KoenWindey](https://discourse.nodered.org/u/KoenWindey)\
**Replies:** 6\
**Last updated:** [5 November 2020 18:57 UTC](https://discourse.nodered.org/t/raspberry-pi-desktop-installation/14778 "2020-11-05T18:57:21Z")

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Hi, I'm running Raspberry Pi Desktop (https://www.raspberrypi.org/downloads/) in a VirtualBox VM and was hoping to install Node Red using the Raspberry Pi script provided here: https://nodered.org/docs/getting-started/r…

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## [MQTT with node-red or home assistant](https://discourse.nodered.org/t/mqtt-with-node-red-or-home-assistant/35383)

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**Author:** [@jordan](https://discourse.nodered.org/u/jordan)\
**Replies:** 1\
**Last updated:** [5 November 2020 17:09 UTC](https://discourse.nodered.org/t/mqtt-with-node-red-or-home-assistant/35383 "2020-11-05T17:09:17Z")

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Hi guys, I would like to learn how to setup MQTT device with node-red or home assistant. My plan is to monitor different parts at home (temp, humidity etc.) so I thought sensors connected with MQTT and then MQTT would …

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## [Ascii codec can't encode character](https://discourse.nodered.org/t/ascii-codec-cant-encode-character/35370)

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**Author:** [@dclear](https://discourse.nodered.org/u/dclear)\
**Replies:** 1\
**Last updated:** [5 November 2020 16:47 UTC](https://discourse.nodered.org/t/ascii-codec-cant-encode-character/35370 "2020-11-05T16:47:02Z")

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Hi! I'm using a Python script which returns the currently playing/on air DJs on the BBC at the moment. Has worked well for months. Now I find it actually fails if there's an apostrophe in the output. Can I fix this some…

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## [Node-red-contrib-pcap installation failed](https://discourse.nodered.org/t/node-red-contrib-pcap-installation-failed/35368)

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**Author:** [@rparada](https://discourse.nodered.org/u/rparada)\
**Replies:** 5\
**Last updated:** [5 November 2020 16:04 UTC](https://discourse.nodered.org/t/node-red-contrib-pcap-installation-failed/35368 "2020-11-05T16:04:53Z")

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Hi, I've tried to install the node pcap " node-red-contrib-pcap" from node-red (palette) but installation fails. Then, I've installed it following the github steps through terminal. Still, I cannot see the pcap node in …

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## [Pulse counting energymeter](https://discourse.nodered.org/t/pulse-counting-energymeter/35334)

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**Author:** [@HDM](https://discourse.nodered.org/u/HDM)\
**Replies:** 4\
**Last updated:** [5 November 2020 13:56 UTC](https://discourse.nodered.org/t/pulse-counting-energymeter/35334 "2020-11-05T13:56:12Z")

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good day thank you in advance it is necessary to count the pulses at a time at a time can come and 0, 1, 2 different numbers how do I implement this

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## [Raspian Jessie not supported with latest bash script](https://discourse.nodered.org/t/raspian-jessie-not-supported-with-latest-bash-script/17617)

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**Author:** [@jsolderitsch](https://discourse.nodered.org/u/jsolderitsch)\
**Replies:** 35\
**Last updated:** [5 November 2020 13:40 UTC](https://discourse.nodered.org/t/raspian-jessie-not-supported-with-latest-bash-script/17617 "2020-11-05T13:40:36Z")

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The recommended bash script to install node-red into debian is: bash \<(curl -sL https://raw.githubusercontent.com/node-red/linux-installers/master/deb/update-nodejs-and-nodered) This worked last week or so but is broke…

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## [Palette Manager installation leave invalid tag in package.json](https://discourse.nodered.org/t/palette-manager-installation-leave-invalid-tag-in-package-json/35256)

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**Author:** [@Mling](https://discourse.nodered.org/u/Mling)\
**Replies:** 16\
**Last updated:** [5 November 2020 11:23 UTC](https://discourse.nodered.org/t/palette-manager-installation-leave-invalid-tag-in-package-json/35256 "2020-11-05T11:23:39Z")

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Node-red version 1.2.2 new Palette Manager installation leave invalid tag in package.json. This cause error on any further npm installation. 2020-11-03T05:04:29.804Z \[err\] ERR! Invalid tag name ""~"0.0.3": Tags may n…

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## [Optional chaining, nullish coalescing operators in function node](https://discourse.nodered.org/t/optional-chaining-nullish-coalescing-operators-in-function-node/35333)

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**Author:** [@PlkMarudny](https://discourse.nodered.org/u/PlkMarudny)\
**Replies:** 7\
**Last updated:** [5 November 2020 10:45 UTC](https://discourse.nodered.org/t/optional-chaining-nullish-coalescing-operators-in-function-node/35333 "2020-11-05T10:45:40Z")

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Hi, I try to use optional chaining operator in 'function' node, but I get "The workspace contains some nodes that are not properly configured" error. Node.js version is 14.x, so it should be supported. Am I missing some…

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## [Listen UDP flows](https://discourse.nodered.org/t/listen-udp-flows/35364)

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**Author:** [@rparada](https://discourse.nodered.org/u/rparada)\
**Replies:** 2\
**Last updated:** [5 November 2020 10:24 UTC](https://discourse.nodered.org/t/listen-udp-flows/35364 "2020-11-05T10:24:09Z")

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Hi, I'm trying to read UDP dataframes (below snap from WS): The private IP is from the running VB instance and the public one, an external PC. This is my flow: \[{"id":"96e009b8.b4f988","type":"tab","label":"Flow 1"…

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## [Using window-status in node-red](https://discourse.nodered.org/t/using-window-status-in-node-red/35190)

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**Author:** [@trombose009](https://discourse.nodered.org/u/trombose009)\
**Replies:** 9\
**Last updated:** [5 November 2020 07:49 UTC](https://discourse.nodered.org/t/using-window-status-in-node-red/35190 "2020-11-05T07:49:22Z")

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Hi everybody, after getting great help corresponding my last (and very first) topic, I have another two questions. My goal is to send mqtt messages from some kind of mcu (esp32/esp8266/etc) to node-red and write it int…

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## [Firefox not loading node-red web UI on LAN](https://discourse.nodered.org/t/firefox-not-loading-node-red-web-ui-on-lan/33417)

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**Author:** [@agt-theharles.me.uk](https://discourse.nodered.org/u/agt-theharles.me.uk)\
**Replies:** 5\
**Last updated:** [5 November 2020 07:47 UTC](https://discourse.nodered.org/t/firefox-not-loading-node-red-web-ui-on-lan/33417 "2020-11-05T07:47:06Z")

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Firefox browser just presented me with a blank page. So I have just wasted two hrs of my life, restoring a RPI image and copying nodes. After the restored from backup and problem was still there it was then I discovered…

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## [How to stop an exec Node, run another exec Node and when it's finished rerun the first](https://discourse.nodered.org/t/how-to-stop-an-exec-node-run-another-exec-node-and-when-its-finished-rerun-the-first/14416)

<div class="topic-metadata">

**Author:** [@HilalAlHakani1](https://discourse.nodered.org/u/HilalAlHakani1)\
**Replies:** 10\
**Last updated:** [5 November 2020 07:42 UTC](https://discourse.nodered.org/t/how-to-stop-an-exec-node-run-another-exec-node-and-when-its-finished-rerun-the-first/14416 "2020-11-05T07:42:55Z")

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Hello i'm new to Node Red , i'm working with a Lora Gps Hat. i have raspberry C code to send Data and another to receive data . the Lora hat can't be receiving and emitting at the same time i have tested the exec Node…

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## [How to extract images from PDF?](https://discourse.nodered.org/t/how-to-extract-images-from-pdf/16846)

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**Author:** [@softy2k](https://discourse.nodered.org/u/softy2k)\
**Replies:** 2\
**Last updated:** [5 November 2020 07:30 UTC](https://discourse.nodered.org/t/how-to-extract-images-from-pdf/16846 "2020-11-05T07:30:13Z")

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Hello I am looking for a way to extract (multiple) images from a pdf file. I don\`t want to convert, I need to extract. Thanks

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## [Barcode scanner output data](https://discourse.nodered.org/t/barcode-scanner-output-data/35268)

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**Author:** [@alex1](https://discourse.nodered.org/u/alex1)\
**Replies:** 3\
**Last updated:** [4 November 2020 23:47 UTC](https://discourse.nodered.org/t/barcode-scanner-output-data/35268 "2020-11-04T23:47:00Z")

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My connecting my usb wireless scanner with raspberry pi zero w then try to display data on nodered. However, the data i get is as shown in the picture. How can i convert it to readable number or string?

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## [Node-Red REST API Call](https://discourse.nodered.org/t/node-red-rest-api-call/35346)

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**Author:** [@GulamGaus](https://discourse.nodered.org/u/GulamGaus)\
**Replies:** 1\
**Last updated:** [4 November 2020 23:18 UTC](https://discourse.nodered.org/t/node-red-rest-api-call/35346 "2020-11-04T23:18:26Z")

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Hi, I am new to Node-Red and learning Node-Red. Received a requirement to connect with REST API with given user, Password and clientId. Any example around this? Thanks.

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## [I want to create my script on github and pull it to NodeRed ... Will it work?](https://discourse.nodered.org/t/i-want-to-create-my-script-on-github-and-pull-it-to-nodered-will-it-work/35232)

<div class="topic-metadata">

**Author:** [@ComboKnight](https://discourse.nodered.org/u/ComboKnight)\
**Replies:** 15\
**Last updated:** [4 November 2020 23:07 UTC](https://discourse.nodered.org/t/i-want-to-create-my-script-on-github-and-pull-it-to-nodered-will-it-work/35232 "2020-11-04T23:07:18Z")

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I created a test script on Github and want to pull that script on to nodered .... I know the vice-versa is possible i.e. pulling the script from local machine to NodeRed and then committing the changes to Github.

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## [Can't see more flows (after upgrade)](https://discourse.nodered.org/t/cant-see-more-flows-after-upgrade/35342)

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**Author:** [@GiovanniG](https://discourse.nodered.org/u/GiovanniG)\
**Replies:** 3\
**Last updated:** [4 November 2020 21:49 UTC](https://discourse.nodered.org/t/cant-see-more-flows-after-upgrade/35342 "2020-11-04T21:49:15Z")

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Hi, thanks for help, here is the story: I've got the SD corrupted, I bought a new one and I cloned there an old SD image I did last months. Node red 0,20 was working with the old flow. Then I start upgrade raspbian, nod…

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## [On smart speaker voice command collect retained topic value from MQTT server and speak it out](https://discourse.nodered.org/t/on-smart-speaker-voice-command-collect-retained-topic-value-from-mqtt-server-and-speak-it-out/34955)

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**Author:** [@kes](https://discourse.nodered.org/u/kes)\
**Replies:** 10\
**Last updated:** [4 November 2020 17:13 UTC](https://discourse.nodered.org/t/on-smart-speaker-voice-command-collect-retained-topic-value-from-mqtt-server-and-speak-it-out/34955 "2020-11-04T17:13:30Z")

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How do I collect a retained topic from the MQTT server and pass it to NORA. eg "Hey Google, what is the boiler pressure." I have the boiler pressure updated to the MQTT server every 2 mins. I had an extensive play las…

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## [Function node problem with ver 1.2.2](https://discourse.nodered.org/t/function-node-problem-with-ver-1-2-2/35320)

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**Author:** [@panmanjon](https://discourse.nodered.org/u/panmanjon)\
**Replies:** 4\
**Last updated:** [4 November 2020 15:20 UTC](https://discourse.nodered.org/t/function-node-problem-with-ver-1-2-2/35320 "2020-11-04T15:20:44Z")

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I developed a flow on a raspberry pi using version node-red 1.1.2 and node.js ver 14.6.0 which works fine. It takes in can data from a battery and serial data from a victron mppt 150¦70-tr. The battery and serial data ar…

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## [MQTT - full topic alias](https://discourse.nodered.org/t/mqtt-full-topic-alias/35255)

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**Author:** [@thalesmaoa](https://discourse.nodered.org/u/thalesmaoa)\
**Replies:** 8\
**Last updated:** [4 November 2020 12:41 UTC](https://discourse.nodered.org/t/mqtt-full-topic-alias/35255 "2020-11-04T12:41:55Z")

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Hi, I’m building a new server to run Emoncms and NodeRed with MQTT as base com protocol. I have, at least, 10 relay command to be executed in this system And more 20 sensors inside a container that will be send 500km a…

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## [Image analysis and comparison](https://discourse.nodered.org/t/image-analysis-and-comparison/20698)

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**Author:** [@hathemi](https://discourse.nodered.org/u/hathemi)\
**Replies:** 5\
**Last updated:** [4 November 2020 10:31 UTC](https://discourse.nodered.org/t/image-analysis-and-comparison/20698 "2020-11-04T10:31:30Z")

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i want to compare two images and detect the percentage difference between them. can this be done with node-red module?

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## [Change function to read .txt file for chart](https://discourse.nodered.org/t/change-function-to-read-txt-file-for-chart/35315)

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**Author:** [@rand](https://discourse.nodered.org/u/rand)\
**Replies:** 1\
**Last updated:** [4 November 2020 09:23 UTC](https://discourse.nodered.org/t/change-function-to-read-txt-file-for-chart/35315 "2020-11-04T09:23:07Z")

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Hi, I am having an issue trying to format my .txt to be able to display on my chart. Currently my .txt is displaying like this and I’m able to shore data on graph: 4,2020-11-02,18:28:37 However, my .txt is being chang…

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## [Install all project dependencies from command line](https://discourse.nodered.org/t/install-all-project-dependencies-from-command-line/16039)

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**Author:** [@corbosman](https://discourse.nodered.org/u/corbosman)\
**Replies:** 6\
**Last updated:** [4 November 2020 09:17 UTC](https://discourse.nodered.org/t/install-all-project-dependencies-from-command-line/16039 "2020-11-04T09:17:26Z")

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Hi all, if I have a local project, and move it to other installations, it there a way to install the project dependencies listed in the project package.json from the command line?

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## [AWS IoT Publishing duplicate msgs](https://discourse.nodered.org/t/aws-iot-publishing-duplicate-msgs/35009)

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**Author:** [@DizzyLurker](https://discourse.nodered.org/u/DizzyLurker)\
**Replies:** 10\
**Last updated:** [4 November 2020 09:07 UTC](https://discourse.nodered.org/t/aws-iot-publishing-duplicate-msgs/35009 "2020-11-04T09:07:52Z")

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Hi, I am having an issue where I am using Node-REDs input MQTT nodes to publish/subscribe to topics via the AWS IoT core broker. I am using QOS 0. The issue is when subscribed to the topics on Node-RED I will get dupl…

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## [Trigger dashboard notification based on chart data from .txt](https://discourse.nodered.org/t/trigger-dashboard-notification-based-on-chart-data-from-txt/35308)

<div class="topic-metadata">

**Author:** [@rand](https://discourse.nodered.org/u/rand)\
**Replies:** 1\
**Last updated:** [4 November 2020 09:03 UTC](https://discourse.nodered.org/t/trigger-dashboard-notification-based-on-chart-data-from-txt/35308 "2020-11-04T09:03:05Z")

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Hi so I am having an issue; I want a notification to appear on my dashboard based on the result on my chart. For example, if my total on my chart is above 42, a notification to be triggered. Here is my flow, please let…

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## [Trigger-empty node](https://discourse.nodered.org/t/trigger-empty-node/35201)

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**Author:** [@jordirt](https://discourse.nodered.org/u/jordirt)\
**Replies:** 5\
**Last updated:** [4 November 2020 07:39 UTC](https://discourse.nodered.org/t/trigger-empty-node/35201 "2020-11-04T07:39:11Z")

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good morning. I have a problem with the trigger-empty node: I send on or off and it gives me this error: TypeError: triggers.keys is not a function " A few weeks ago it worked correctly for me since it does not have muc…

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## [Alexa Home, need a skill?](https://discourse.nodered.org/t/alexa-home-need-a-skill/35301)

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**Author:** [@SteveMann](https://discourse.nodered.org/u/SteveMann)\
**Replies:** 0\
**Last updated:** [3 November 2020 23:18 UTC](https://discourse.nodered.org/t/alexa-home-need-a-skill/35301 "2020-11-03T23:18:08Z")

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I am using Alexa Home nodes to turn things on or off. Usually ESP-based stuff mostly flashed with Tasmota. All of my devices are defined on https://alexa-node-red.bm.hardill.me.uk/devices I have Alexa Auto in my car an…

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## [Stop executing the python code using "Python Shell" Node](https://discourse.nodered.org/t/stop-executing-the-python-code-using-python-shell-node/35194)

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**Author:** [@Sandy](https://discourse.nodered.org/u/Sandy)\
**Replies:** 7\
**Last updated:** [3 November 2020 21:30 UTC](https://discourse.nodered.org/t/stop-executing-the-python-code-using-python-shell-node/35194 "2020-11-03T21:30:02Z")

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Hi All, I executed a python script(taken locally) using a python shell node in node-red. But As I am running Infinite Loop code I was unable to stop the execution. Please Help me out..?

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