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Can't save/create files using Store.js

So I wanted to save a file on the client storage using Store.js.
I can change the date using store.set and i can log it to console to see the change, but then it's supposed to be saved in app data where it's not created.
I tried to get the Path where it's being saved and it's :
C:\Users\USER\AppData\Roaming\stoma2/Categories.json
I noticed that there is a "/" so I tried :
C:\Users\USER\AppData\Roaming\stoma2\Categories.json
and :
C:/Users/USER/AppData/Roaming/stoma2/Categories.json
But all 3 of them didn't work.
This is my Store.js :
const fs = require('browserify-fs');
var fs2 = require('filereader'),Fs2 = new fs2();
const electron = window.require('electron');
const path = require('path');
class Store {
constructor(opts) {
// Renderer process has to get `app` module via `remote`, whereas the main process can get it directly
// app.getPath('userData') will return a string of the user's app data directory path.
//const userDataPath = (electron.app || electron.remote.app).getPath('userData');
var userDataPath = (electron.app || electron.remote.app).getPath('userData');
for(var i=0;i<userDataPath.length;i++){
if(userDataPath.charAt(i)=="\\"){
userDataPath = userDataPath.replace("\\","/");
}
}
// We'll use the `configName` property to set the file name and path.join to bring it all together as a string
this.path = path.join(userDataPath, opts.configName + '.json');
this.data = parseDataFile(this.path, opts.defaults);
console.log(this.path);
}
// This will just return the property on the `data` object
get(key) {
return this.data[key];
}
// ...and this will set it
set(key, val) {
this.data[key] = val;
// Wait, I thought using the node.js' synchronous APIs was bad form?
// We're not writing a server so there's not nearly the same IO demand on the process
// Also if we used an async API and our app was quit before the asynchronous write had a chance to complete,
// we might lose that data. Note that in a real app, we would try/catch this.
fs.writeFile(this.path, JSON.stringify(this.data));
}
}
function parseDataFile(filePath, data) {
// We'll try/catch it in case the file doesn't exist yet, which will be the case on the first application run.
// `fs.readFileSync` will return a JSON string which we then parse into a Javascript object
try {
return JSON.parse(Fs2.readAsDataURL(new File(filePath)));
} catch(error) {
// if there was some kind of error, return the passed in defaults instead.
return data;
}
}
// expose the class
export default Store;
There might be a probleme fith js.writeFile() (well that's the source of probleme).
and this is my call :
//creation
const storeDefCat = new Store({
configName: "Categories",
defaults: require("../data/DefaultCategorie.json")
})
//call for the save
storeDefCat.set('Pizza',{id:0,path:storeDefCat.get('Pizza').path});
For now if possible,I might need to find another way to save the file.
And i tried : fs : It doesn't work for me for some reason (I get strange errors that they don't want to be fixed..) .
If anyone has an Idea then please I would be grateful.

So I managed to fix the probleme, Why fs was sending me errors about undefined functions?Why file wasn't getting created ? It has NOTHING to do with the code it self, but the imports...
To clearify, I was using :
const fs = require('fs');
And the solution is to make it like :
const fs = window.require('fs');
Just adding window. fixed all the problems .Since it's my first time using electron I wasn't used to import from the window but it seems it's necessary.And more over...There was no posts saying this is the fix.

Unable to read config.json file in node.js

I am writing a unit test case for the , question is mentioned in the link How to stub/mock submodules of a require of nodejs using sinon
when I include a require
const index=require('./index.js');
It has a library require inside it
const library= require('./library.js');
the library.js file has a require which reads config.json file(this config file is also required inside above index.js) as below
const readConfig = require('read-config');
const config = readConfig('./config.json');
I have tried many ways as suggested in the above link but I am failing
const stubs = {
'./library': function (response) {
assert.equal(some, null);
return 'Some ' + argument;
},
'../library1.js': {
function(paths, opts){
var config='./config.json'
return config;
}
},
}
const index=proxyquire('./index.js',stubs)
When I run my unit test case I am still getting the below error
throw configNotFound(configPath);
^
ReadConfigError: Config file not found: ./config.json
I would like to know which part of the code I am missing badly that the code throws the error
I am trying to edit the index.js and all the related files where config is read with the below code
var path = require('path');
var pathToJson = path.resolve(__dirname, '../config.json');
// Load config
var config = fs.readFile(pathToJson , 'utf8', function (err, data) {
if (err) throw err;
config = JSON.parse(data);
});
Here challenge is that I cannot change the node code

You problem is likely to be path resolution. If ./config.json is relative to where you are running Node from (process.cwd()), then it'll work. If it's relative to your library module, then you can do something like:
// Works for JS and JSON
const configPath = require.resolve('./config.json');
// Works in general
const configPath = require('path').join(__dirname, 'config.json');
// Then
const readConfig = require('read-config');
const config = readConfig(configPath);
It's difficult to say if this is the case without knowing more about your project layout and how you're starting your app.

Node Js: How to catch a "No such file or directory" error in readline module

I'm working on a program that reads a file line by line with the readline module. First I get the file name by command line, but I want to check if the file actually exists. I have read about fs.stat() but I want to know if there is a way to catch the error directly with readline. So far I've tried this
try{
var line_reader = read_line.createInterface({
input: file_stream.createReadStream(file_name)
});
}catch(err){
console.log('Please insert a valid file name');
}
But I still get the message
Error: ENOENT: no such file or directory

The exception is thrown by createReadStream.
You need to add 'on error' case to createReadStream:
var fs = file_stream.createReadStream(file_name)
fs.on('error', function (err) {
// handle error here
});
var line_reader = read_line.createInterface({
input: fs
});

Miss read your question at the beginning and updated my answer.
A solution you could use fs.stat
Edit
// fs.stat is async
fs.stat(file_name, function(err,stat){
if (stat && stat.isFile() ) {
var line_reader = read_line.createInterface({
input: file_stream.createReadStream(file_name)
});
}
});

local PDF file scraping in node.js

I have uploaded a pdf via a MEAN stack web application using fs. I want to extract certain fields from the pdf and display them on the web app. I have looked at a couple npm packages like pdf.js, pdf2json. I can't figure out the documentation and javascript callbacks used in the examples available. Please help!

I hope I can help answer your question. Using pdf2json can be used to parse a pdf and extract the text. There are a couple of steps that need to be taken to get it working. I have adapted the example from https://github.com/modesty/pdf2json.
The setup is to install pdf2json in the node app, and also underscore. The example page didn't explain the need to define your own callback functions. It also used self instead of this to register them. So, with the appropriate changes the code to extract all the text from the pdf will be something like this:
// Get the dependencies that have already been installed
// to ./node_modules with `npm install <dep>`in the root director
// of your app
var _ = require('underscore'),
PDFParser = require('pdf2json');
var pdfParser = new PDFParser();
// Create a function to handle the pdf once it has been parsed.
// In this case we cycle through all the pages and extraxt
// All the text blocks and print them to console.
// If you do `console.log(JSON.stringify(pdf))` you will
// see how the parsed pdf is composed. Drill down into it
// to find the data you are looking for.
var _onPDFBinDataReady = function (pdf) {
console.log('Loaded pdf:\n');
for (var i in pdf.data.Pages) {
var page = pdf.data.Pages[i];
for (var j in page.Texts) {
var text = page.Texts[j];
console.log(text.R[0].T);
}
}
};
// Create an error handling function
var _onPDFBinDataError = function (error) {
console.log(error);
};
// Use underscore to bind the data ready function to the pdfParser
// so that when the data ready event is emitted your function will
// be called. As opposed to the example, I have used `this` instead
// of `self` since self had no meaning in this context
pdfParser.on('pdfParser_dataReady', _.bind(_onPDFBinDataReady, this));
// Register error handling function
pdfParser.on('pdfParser_dataError', _.bind(_onPDFBinDataError, this));
// Construct the file path of the pdf
var pdfFilePath = 'test3.pdf';
// Load the pdf. When it is loaded your data ready function will be called.
pdfParser.loadPDF(pdfFilePath);

I am running the code out of my server side controller.
module.exports = (function() {
return {
add: function(req, res) {
var tmp_path = req.files.pdf.path;
var target_path = './uploads/' + req.files.pdf.name;
fs.rename(tmp_path, target_path, function(err) {
if (err) throw err;
// delete the temporary file, so that the explicitly set temporary upload dir does not get filled with unwanted files
fs.unlink(tmp_path, function() {
if (err) throw err;
//edit here pdf parser
res.redirect('#/');
});
})
},
show: function(req, res) {
var pdfParser = new PDFParser();
var _onPDFBinDataReady = function (pdf) {
console.log('Loaded pdf:\n');
for (var i in pdf.data.Pages) {
var page = pdf.data.Pages[i];
// console.log(page.Texts);
for (var j in page.Texts) {
var text = page.Texts[j];
// console.log(text.R[0].T);
}
}
console.log(JSON.stringify(pdf));
};
// Create an error handling function
var _onPDFBinDataError = function (error) {
console.log(error);
};
pdfParser.on('pdfParser_dataReady', _.bind(_onPDFBinDataReady, this));
// Register error handling function
pdfParser.on('pdfParser_dataError', _.bind(_onPDFBinDataError, this));
// Construct the file path of the pdf
var pdfFilePath = './uploads/Invoice_template.pdf';
// Load the pdf. When it is loaded your data ready function will be called.
pdfParser.loadPDF(pdfFilePath);
},
//end controller
}

PhantomJS copy file with overwrite

Reading from their document:
copy(source, destination)
Currently, the way I cope with this is to check fs.exist('myfile') and manual delete it prior to copy:
var fs = require('fs');
var fileName = 'myfile-backup.txt';
if (fs.exists(fileName)) {
fs.remove(fileName);
}
fs.copy('myfile.txt', fileName);
phantom.exit();
I don't know if there is any better way to overwrite the file. Checking for existing file may have a potential problem when I can't remove the file. I will probably need to do more error handling with this approach. It seems to be a common task, so I would like to know what solution people come up with.

I have written a small extension to the fs module. If you try to overwrite a file with fs.copy it will throw an exception which you can catch to do some error handling like removing an existing file.
I also added an optional maxTrials argument if there is a problem that the file is created every time in between the copy trial and the remove.
var fs = require('fs');
fs.overwrite = function(source, destination, maxTrials){
var overwritten = false;
var trials = 0;
maxTrials = parseInt(maxTrials)
maxTrials = !!maxTrials ? maxTrials : null;
while(!overwritten) {
if (maxTrials && trials > maxTrials) {
return -1;
}
try {
this.copy(source, destination);
overwritten = true;
} catch(e) {
if (fs.exists(destination)) {
fs.remove(destination);
} else {
return -2;
}
}
trials++;
}
return trials;
};