Node.js Stream readable.readableLength Property

The readable.readableLength property in a readable Stream that is used to check the number of bytes in the queue which is ready to be read. Syntax:

readable.readableLength

Return Values: It returns the number of bytes in the queue which are ready to be read. Below examples illustrate the use of readable.readableLength property in Node.js: Example 1:

JavaScript

// Node.js program to demonstrate the     
// readable.readableLength Property
 
// Accessing stream module
const stream = require('stream');
 
// Creating a Readable stream 
const readable = new stream.Readable("input.txt");
 
// Calling readable.readableLength 
// Property
readable.readableLength;

Output:

Example 2:

JavaScript

// Node.js program to demonstrate the     
// readable.readableLength property  
 
// Include fs module
const fs = require("fs");
 
// Constructing readable stream
const readable = fs.createReadStream("input.txt");
 
// Instructions for reading data
readable.on('readable', () => {
  let chunk;
 
  // Using while loop and calling
  // read method
  while (null !== (chunk = readable.read())) {
 
    // Displaying the chunk length
    console.log(`read: ${chunk.length}`);
     }
});

// Calling readableLength property
readable.readableLength;

Output:

0
read: 13

Reference: https://nodejs.org/api/stream.html#stream_readable_readablelength.

Node.js Stream readable.readableLength Property

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