Node JS - How to write stream big json data into json array file?
<p>I have difficult to write a json data into json file using <code>stream</code> module.
I learn about this from several blog tutorial, one of them is this <a href="https://www.sandersdenardi.com/readable-writable-transform-streams-node/" rel="noreferrer">page</a> </p>

<p>Let say i am working with big json data on a json file. I think it is not possible to store all json object inside my memory. So i decided to do it using stream module.</p>

<p>Here the codes i have done:</p>

<p>writeStream.js</p>

<pre><code>var Writable = require('stream').Writable,
util = require('util');

var WriteStream = function() {
    Writable.call(this, {
        objectMode: true
    });
};

util.inherits(WriteStream, Writable);

WriteStream.prototype._write = function(chunk, encoding, callback) {
    console.log('write            : ' + JSON.stringify(chunk));
    callback();
};

module.exports = WriteStream;
</code></pre>

<p>readStream.js</p>

<pre><code>var data = require('./test_data.json'),
Readable = require('stream').Readable,
util = require('util');

var ReadStream = function() {
    Readable.call(this, {
        objectMode: true
    });

    this.data = data;
    this.curIndex = 0;
};

util.inherits(ReadStream, Readable);

ReadStream.prototype._read = function() {
    if (this.curIndex === this.data.length) {
        return this.push(null);
    }

    var data = this.data[this.curIndex++];
    console.log('read             : ' + JSON.stringify(data));
    this.push(data);
};

module.exports = ReadStream;
</code></pre>

<p>Called with this code:</p>

<pre><code>var ReadStream = require('./readStream.js'),
WriteStream = require('./writeStream.js');

var rs = new ReadStream();
var ws = new WriteStream();
rs.pipe(ws);
</code></pre>

<p>Problem: I want to write it into different file, how is it possible?
Can you please help me?</p>