How to Access JSON Data in Node.js Server Memory?

Accessing JSON Data in Node.js Server Memory

In the realm of Node.js development, it often becomes necessary to access JSON objects residing in external files into server memory for quick retrieval.

To accomplish this task, you have two primary options: reading from a text file or a JS file. The choice between the two depends on your specific needs and preferences.

To read a JSON object from a text file into server memory using JavaScript/Node, follow these steps:

Synchronous Approach:

1. Require the 'fs' (file system) module: var fs = require('fs');
2. Utilize the fs.readFileSync() method to retrieve the file's contents: var data = fs.readFileSync('file', 'utf8');
3. Parse the retrieved data into a JavaScript object using JSON.parse(): var obj = JSON.parse(data);

Asynchronous Approach:

1. Still require the 'fs' module: var fs = require('fs');
2. Use the fs.readFile() method to asynchronously read the file: fs.readFile('file', 'utf8', function (err, data) {});
3. Inside the callback function, parse the data into a JSON object: JSON.parse(data);

For your convenience, here are code snippets for both approaches:

Synchronous:

var fs = require('fs');
var obj = JSON.parse(fs.readFileSync('file', 'utf8'));

Asynchronous:

var fs = require('fs');
var obj;
fs.readFile('file', 'utf8', function (err, data) {
  if (err) throw err;
  obj = JSON.parse(data);
});

Once you have loaded the JSON object into memory, you can access its properties and values directly from your JavaScript code, enabling efficient data retrieval and processing within your Node.js server.

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