Problem with "require" in custom module

Wappler General How To
#1

Still no expert on custom modules but trying my hardest!!

Decided to take a quick look at an Paypal IPN solution for Node after noticing an npm “paypal-ipn”

So i installed with

npm install paypal-ipn

I can see it installed:

image
typing into terminal

npm ls

shows it installed:

image

and checking package-lock.json correctly shows its presence and version

image

however when i try to use it

image

I get a not found error

image
image704×517 16.4 KB

Anyone any ideas where things are going wrong?

#2

If you are using a Docker development environment with Node try reinstalling all packages

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#3

node local server, made not difference

#4 
const ipn = require('paypal-ipn);

module.exports = {
    yourIPNfunction: function(options) {
        //options contains the input data you use in the UI for this SC action. You will probably pass the params that the IPN verify function needs via a binding in the UI. 
        ipn.verify(params, function callback(err, msg) {
            if (err) {
                console.error(err);
            } else {
               // Do stuff with original params here
               if (params.payment_status == 'Completed') {
               // Payment has been confirmed as completed, return something
                   return true
               }
               else { 
                   return false
               }
            }
        });
    }
}

In the hsjon file the action key needs to have the value yourIPNfunction

#5

Out of curiosity I did a test:
Wappler 4.9.1
MacOS Monterey
Local docker + node

I installed npm paypal-ipn from the wappler terminal
when i try to run the script it returns the same error as you.

I tried to reinstall the node modules but it still doesn’t work

In my case the solution is this:

In the Docker desktop application window go to Containers and then click on CLI,

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from here a terminal window will open, launch the command npm install paypal-ipn and finally restart all Docker services

now the script does not return any errors

Wappler 4.9.1
MacOS Monterey
Local node

I installed npm paypal-ipn from the wappler terminal

No problems found

#6

Thanks a lot for the code tidy up @JonL , much appreciated. You are a great help to this community. Unfortunately the “require” issue remained HOWEVER also thanks to @Pier, your solution worked perfectly i.e. installing npm via docker container. Starting to wonder is all it may have needed was a simple deploy to local target?, i can remember if i did or not

#7

If you are using a local server an npm install in the project folder and a require should be more than enough. Installing the module in a docker container shouldn’t make a difference at all given that you are not using docker to develop your app.

Something is wrong here.

#8

Yes, me! Thought my testbed was set up to use inbuild node server (that’s my normal setup) but for some strange reason i had set this one up in docker local.
Only when I saw Pier’s post did I check and realise what i had done
My Bad

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