How to edit server stored JSON file with NodeJS - angularjs

Question

I have a web server hosting over localhost. The website I am accessing is a "Todo list app" written with AngularJS. To load the todo's, the browser gets a JSON file with the information. An example of this:
[
{"name":"Clean the house"},
{"name":"Water the dog"},
{"name":"Feed the lawn"},
{"name":"Pay dem bills"},
{"name":"Run"},
{"name":"Swim"}
]
It then loops through all the items and "prints" them out onto the website. I have various options like "Save" and "Delete". They work client-side, but that way does not allow me to properly save them, as when the browser is refreshed, all the content is reset with the server's static JSON file.
I was wondering if there was some way of using NodeJs to host the website and listen for incoming AJAX request and edit the content in the file based off that.

Answer 1

Writing a file asynchronously in nodejs can be done as follows.
var fs = require('fs');
var fileName = './file.json';
var file = require(fileName);
file.key = "new value"; // This will be coming as a http POST method from your view
fs.writeFile(fileName, JSON.stringify(file), function (err) {
if (err) return console.log(err);
console.log(JSON.stringify(file));
console.log('writing to ' + fileName);
});
The caveat is that json is written to the file on one line and not prettified. ex:
{
"key": "value"
}
will be...
{"key": "value"}
To avoid this, simply add these two extra arguments to JSON.stringify
JSON.stringify(file, null, 2)
null - represents the replacer function. (in this case we don't want to alter the process)
2 - represents the spaces to indent.

Answer 2

NodeJS does not persist data out of the box.
You want something like NodeJS + Express and special CRUD routes like POST for creating items or DELETE for deleting them.
In this routes you have to add a data persistance layer like mongoose if you want to use MongoDB or Sequelize if you want to add a SQL database behind it.
Each of this ORM requires to specify a Datamodel which can be saved.
Here an example for a mongoose implementation:
'use strict';
/**
* Module dependencies.
*/
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var plugins = require('./model.server.plugins');
/**
* Customer Schema
*/
var CustomerSchema = new Schema({
name: {
type: String,
default: '',
required: 'Please fill a name',
trim: true
},
created: {
type: Date,
default: Date.now
}
});
mongoose.model('Customer', CustomerSchema);
Here is the controller
'use strict';
/**
* Module dependencies.
*/
var mongoose = require('mongoose'),
errorHandler = require('./errors.server.controller'),
Customer = mongoose.model('Customer'),
_ = require('lodash');
/**
* Create a Customer
*/
exports.create = function(req, res) {
var customer = new Customer(req.depopulated);
customer.user = req.user;
customer.save(function(err) {
if (err) {
return res.status(400).send({
message: errorHandler.getErrorMessage(err)
});
} else {
res.jsonp(customer);
}
});
};
Here the route
router.route('/')
.post(customers.create);