fs.readFile, fs.writeFile, fs.readdir

General
1

Hi all,
I'm writing a node-red function and I would like read and write files inside a function using fs module. I correctly imported it but when I tried to read a file the following message appears:
"TypeError: Cannot read properties of undefined (reading 'readFileSync')" (the same with fs.readFile)

PS. When I use writeFile the same error appears but it create and write file and I don't understand why.

can someone help me?
many thanks

2

How did you import fs?
Can you show us your code?
What's wrong with using the built in file nodes?

3 
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4

The main problem is you are trying to use msg.fs from one path and msg.payload from a different path. The most important principle to understand with node-red is that messages from different wires will NEVER arrive at the input of a node at the same time.

Next, i see no reason to use the require node if you have node-red v2+ - as you can import fs using the setup tab on a function node.

Lastly, i see zero reason to actually use fs - you can simply use the built in read file and write file nodes to achieve this in a more graphical / low code manner.

5

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