ssh2-sftp-client get() request giving 'denied permission - error' - node.js

Question

I am using this code in my electron app to connect to an sftp server where I need to collect some data. I have no problem listing the files in the /out folder, but it fails to get the sftp file with 'deined permission' error. Ideally I would like to be able get() file and access the text data within directly in the function without storing to a file.
let Client = require('ssh2-sftp-client');
let sftp = new Client();
var root = '/out';
var today = new Date();
var mon = ((today.getMonth()+1) < 10)? "0" + (today.getMonth()+1) : (today.getMonth()+1);
var date = (today.getDate() < 10)? "0" + today.getDate() : today.getDate();
var fileDate = mon + date;
sftp.connect({
host: '<server-address>',
port: 2222,
username: 'XXXXXXXX',
password: 'xxxxxxxx',
privateKey: fs.readFileSync(path.join(__dirname, '../rsa/<file-name-here>.pem'))
})
.then(() => {
return sftp.list(root, 'SN5M' + fileDate);
})
.then((fileInfo) => {
if (fileInfo) {
var filePath = root + '/' + fileInfo[fileInfo.length - 1].name;
return sftp.get(filePath).then((file) => {
console.log(file);
event.returnValue = file;
sftp.end();
})
.catch((err) => {
console.log('File get error', err);
event.returnValue = err;
sftp.end();
});
}
})
.catch((err) => {
console.log('File info error', err);
event.returnValue = err;
sftp.end();
});

Answer 1

Try this and see if it works or not
'get' returns (String|Stream|Buffer).
let dst = fs.createWriteStream('/local/file/path/data.txt');
sftp.get(filePath,dst)
Refer https://www.npmjs.com/package/ssh2-sftp-client#orga0dfcd5

Answer 2

Looking at your code, you have two problems.
If you call get() with only 1 argument, it returns a buffer, not a file. To get the file, just do
client.get(sourceFilePath, localFilePath)
and the file will be saved locally as localFilePath. Both arguments are strings and need to be full paths i.e. include the filename, not just the directory. The filename for the second argument can be different from the first. However, if all you want is to retrieve the file, you are better off using fastGet() rather than get(). The get() method is good for when you want to do something in the code with the data e.g. a buffer or write stream piping/processing. The fastGet() method is faster than get() as it does the transfer using concurrent processes, but does not permit use of buffers or streams for further processing.
The error message you are seeing is either due to the way you are calling get() or it is an indication you don't have permission to read the file your trying to access (as the user your connected with). Easiest way to check this is to use the openSSH sftp program (available on Linux, mac and windows) and the key your using (use the -i switch) to try and download the file. If it fails with a permission error, then you know it is a permission error and not a problem with your code or ssh2-sftp-client module.
EDIT: I just noticed you are also using both a password and a key file. You don't need both - either one will work, but you don't need to use both. I tend to use a keyfile when possible as it avoids having to have a password stored somewhere. Make sure not to add a passphrase to your key. Alternatively, you can use something like the dotenv module and store your credentials and other config in a .env file which you do not check into version control.