I calculate the cost for my power consumption each hour and I put the different values into a Sum-node. This works fine, but I have noticed that if the flows restart the sum-node is empty. Is it possible to make a function node to store the value and reinsert it into the sum-node if the flows restar…

Isn't it better to have a look why the flow restarts.

I assumed that @FSHelgeland was referring to normal reboot, deploys etc rather than unexpected restarts. Certainly if it is restarting for unknown reasons then that should be addressed.

Colin is absolutely correct, I seldom have to restart my Node Red do to faults or unexpected things. But since I am still pretty new programming and since I am still testing a lot of stuff I do some reebooting and deploys from time to time. And I think it is a good thing to know how to do a memory i…

I understand that i have to uncomment some lines in the settings.js to get to work with context it that correct? And when I try to enter my settings.js it looks like it is read only, at least I can not gett access to it.

[image] FSHelgeland: And when I try to enter my settings.js it looks like it is read only What environment? If linux try "sudo nano...."

It is on a raspberry pi. What should I type then? Just sudo nano?

If you did not get that hint, I have to encourage you to read up a bit more on Node-RED and settings.js etc

Find out where you have the settings.js file located As example in /home/pi/.node-red So you would type "sudo nano /home/pi/.node-red/settings.js" and there you go and can make the edits you need

Node-RED

Node-RED Forum

Store a value and reinsert it when flows start

General

zenofmud 10 July 2022 15:16 16

Here is a topic I wrote (quite awhile ago) that may help you out

Topic		Replies	Views
How do I set flow variables to preserve their value over a restart? General	6	788	9 December 2022
Saving context - advice requested! FAQs	20	1814	4 July 2020
A guide to understanding 'Persistent Context' General	87	46496	4 January 2022
ContextStorage: saving to USB SSD General	10	427	23 November 2022
contextStorage in later versions of NR. Confused General	11	817	25 October 2020

Copyright OpenJS Foundation and Node-RED contributors. All rights reserved. The OpenJS Foundation has registered trademarks and uses trademarks. For a list of trademarks of the OpenJS Foundation, please see our Trademark Policy and Trademark List. Trademarks and logos not indicated on the list of OpenJS Foundation trademarks are trademarks™ or registered® trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.

Store a value and reinsert it when flows start

Related topics