How can I do Base64 encoding in Node.js?

Question

Does Node.js have built-in Base64 encoding yet?

The reason why I ask this is that final() from crypto can only output hexadecimal, binary or ASCII data. For example:

var cipher = crypto.createCipheriv('des-ede3-cbc', encryption_key, iv);
var ciph = cipher.update(plaintext, 'utf8', 'hex');
ciph += cipher.final('hex');

var decipher = crypto.createDecipheriv('des-ede3-cbc', encryption_key, iv);
var txt = decipher.update(ciph, 'hex', 'utf8');
txt += decipher.final('utf8');

According to the documentation, update() can output Base64-encoded data. However, final() doesn't support Base64. I tried and it will break.

If I do this:

var ciph = cipher.update(plaintext, 'utf8', 'base64');
    ciph += cipher.final('hex');

Then what should I use for decryption? Hexadecimal or Base64?

Therefore, I'm looking for a function to Base64-encode my encrypted hexadecimal output.

Abstention

For someone looking for this problem in/after 2016 cipher.final('base64') works – Yellowknife

try base122 github.com/kevinAlbs/Base122 – Ado

Answer 1

Buffers can be used for taking a string or piece of data and doing Base64 encoding of the result. For example:

> console.log(Buffer.from("Hello World").toString('base64'));
SGVsbG8gV29ybGQ=
> console.log(Buffer.from("SGVsbG8gV29ybGQ=", 'base64').toString('ascii'))
Hello World

The Buffer constructor is a global object, so no require is needed. Buffers created with strings can take an optional encoding parameter to specify what encoding the string is in. The available toString and Buffer constructor encodings are as follows:

'ascii' - for 7 bit ASCII data only. This encoding method is very fast, and will strip the high bit if set.

'utf8' - Multi byte encoded Unicode characters. Many web pages and other document formats use UTF-8.

'ucs2' - 2-bytes, little endian encoded Unicode characters. It can encode only BMP(Basic Multilingual Plane, U+0000 - U+FFFF).

'base64' - Base64 string encoding.

'binary' - A way of encoding raw binary data into strings by using only the first 8 bits of each character. This encoding method is deprecated and should be avoided in favor of Buffer objects where possible. This encoding will be removed in future versions of Node.

Fire

const atob = (data) => Buffer.from(data, 'base64').toString('ascii'); – Karns

that should be .toString("binary") (atob stands for ascii(base64) to binary, after all) – Futility

@Futility I thought it stood for ascii to base64? – Suffragette

@DavidCallanan atob() converts from base64 – Futility

I got this warning after Buffer.from (node:13765) [DEP0005] DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead. – Trombley

I have a related question that I think you'll know the answer to. I appreciate your help! https://mcmap.net/q/46653/-buffer-from-base64encodedstring-39-base64-39-tostring-39-binary-39-vs-39-utf8-39/470749 – Flibbertigibbet

"Buffers are a global object, so no require is needed." The NodeJS docs recommend "to explicitly reference it via an import or require statement." – Stormy

Answer 2

The accepted answer previously contained new Buffer(), which is considered a security issue in Node.js versions greater than 6 (although it seems likely for this use case that the input can always be coerced to a string).

The Buffer constructor is deprecated according to the documentation.

The code snippets should read:

console.log(Buffer.from("Hello World").toString('base64'));
console.log(Buffer.from("SGVsbG8gV29ybGQ=", 'base64').toString('ascii'));

After this answer was written, it has been updated and now matches this.

Lavabo

When I try to use your first line, Node returns: [TypeError: this is not a typed array.] – Impish

This error happens on node versions older than v6. In these versions you'll need to use the constructor (new Buffer) rather than Buffer.from. – Lavabo

Buffer.from() was added in v4.5.0. – Guidotti

Just to save you few minutes that I lost trying to see difference between this example and the one in the accepted answer, the accepted answer is now updated to what this answer suggests. – Artima

What is the "ws" library? Can you add a reference to? But without "Edit:", "Update:", or similar - the answer should appear as if it was written today. – Tankoos

Answer 3

crypto now supports Base64 (reference):

cipher.final('base64')

So you could simply do:

var cipher = crypto.createCipheriv('des-ede3-cbc', encryption_key, iv);
var ciph = cipher.update(plaintext, 'utf8', 'base64');
ciph += cipher.final('base64');

var decipher = crypto.createDecipheriv('des-ede3-cbc', encryption_key, iv);
var txt = decipher.update(ciph, 'base64', 'utf8');
txt += decipher.final('utf8');

Rhombencephalon

Any reason to use this over NotJavanese's answer? – Tribute

Had to match encryptions between Node and Python and this answer saved me a question! Thanks :) – Woodwork

This is incorrect since you can't just append multiple base64 strings and get a correctly concatenated base64 string. This only works if the update function returns chunks of length divisible by 4, of which there is no guarantee. – Insincerity

Answer 4

Buffers can be used for taking a string or piece of data and doing Base64 encoding of the result. For example:

You can install Buffer via npm like: npm i buffer --save

You can use this in your js file like this:

var buffer = require('buffer/').Buffer;

->> console.log(buffer.from("Hello Vishal Thakur").toString('base64'));
SGVsbG8gVmlzaGFsIFRoYWt1cg==  // Result

->> console.log(buffer.from("SGVsbG8gVmlzaGFsIFRoYWt1cg==", 'base64').toString('ascii'))
Hello Vishal Thakur   // Result

Crabtree

buffer should be capitalized to Buffer – Gloriagloriana

@RedwolfPrograms as you can see i have imported this require('buffer/').Buffer; at last, you can see Buffer. – Crabtree

Answer 5

I am using the following code to decode a Base64 string in the Node.js API, Node.js version 10.7.0:

let data = 'c3RhY2thYnVzZS5jb20=';  // Base64 string
let buff = new Buffer(data, 'base64');  //Buffer
let text = buff.toString('ascii');  // This is the data type that you want your Base64 data to convert to
console.log('"' + data + '" converted from Base64 to ASCII is "' + text + '"');

Please don't try to run the above code in the console of the browser. It won't work. Put the code in the server-side files of Node.js. I am using the above line code in API development.

Plead

Answer 6

Try doing this :

console.log(Buffer.from("Hello World").toString('base64'));
console.log(Buffer.from("SGVsbG8gV29ybGQ=", 'base64').toString('ascii'));

This will convert a string into base64 encoded string i.e. SGVsbG8gV29ybGQ= and then you can decode it back to Hello World

Crosslegged

Answer 7

I have created an ultimate small JavaScript npm library for the Base64 encode/decode conversion in Node.js.

Installation

npm install nodejs-base64-converter --save

Usage

var nodeBase64 = require('nodejs-base64-converter');

console.log(nodeBase64.encode("test text")); //dGVzdCB0ZXh0
console.log(nodeBase64.decode("dGVzdCB0ZXh0")); //test text

Donetta

no need to install an extra plugin when it is natively supported by nodejs – Frigg

Answer 8

You can do Base64 encoding and decoding with simple JavaScript.

$("input").keyup(function () {
    var value = $(this).val(),
        hash = Base64.encode(value);
    $(".test").html(hash);

    var decode = Base64.decode(hash);

    $(".decode").html(decode);
});

var Base64 = {_keyStr:"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",encode:function(e){var t="";var n,r,i,s,o,u,a;var f=0;e=Base64._utf8_encode(e);while(f<e.length){n=e.charCodeAt(f++);r=e.charCodeAt(f++);i=e.charCodeAt(f++);s=n>>2;o=(n&3)<<4|r>>4;u=(r&15)<<2|i>>6;a=i&63;if(isNaN(r)){u=a=64}else if(isNaN(i)){a=64}t=t+this._keyStr.charAt(s)+this._keyStr.charAt(o)+this._keyStr.charAt(u)+this._keyStr.charAt(a)}return t},decode:function(e){var t="";var n,r,i;var s,o,u,a;var f=0;e=e.replace(/[^A-Za-z0-9+/=]/g,"");while(f<e.length){s=this._keyStr.indexOf(e.charAt(f++));o=this._keyStr.indexOf(e.charAt(f++));u=this._keyStr.indexOf(e.charAt(f++));a=this._keyStr.indexOf(e.charAt(f++));n=s<<2|o>>4;r=(o&15)<<4|u>>2;i=(u&3)<<6|a;t=t+String.fromCharCode(n);if(u!=64){t=t+String.fromCharCode(r)}if(a!=64){t=t+String.fromCharCode(i)}}t=Base64._utf8_decode(t);return t},_utf8_encode:function(e){e=e.replace(/rn/g,"n");var t="";for(var n=0;n<e.length;n++){var r=e.charCodeAt(n);if(r<128){t+=String.fromCharCode(r)}else if(r>127&&r<2048){t+=String.fromCharCode(r>>6|192);t+=String.fromCharCode(r&63|128)}else{t+=String.fromCharCode(r>>12|224);t+=String.fromCharCode(r>>6&63|128);t+=String.fromCharCode(r&63|128)}}return t},_utf8_decode:function(e){var t="";var n=0;var r=c1=c2=0;while(n<e.length){r=e.charCodeAt(n);if(r<128){t+=String.fromCharCode(r);n++}else if(r>191&&r<224){c2=e.charCodeAt(n+1);t+=String.fromCharCode((r&31)<<6|c2&63);n+=2}else{c2=e.charCodeAt(n+1);c3=e.charCodeAt(n+2);t+=String.fromCharCode((r&15)<<12|(c2&63)<<6|c3&63);n+=3}}return t}}

// Define the string
var string = 'Hello World!';

// Encode the string
var encodedString = Base64.encode(string);
console.log(encodedString); // Outputs: "SGVsbG8gV29ybGQh"

// Decode the string
var decodedString = Base64.decode(encodedString);
console.log(decodedString); // Outputs: "Hello World!"</script></div>

This is implemented in this Base64 encoder decoder.

Bonnie

Perhaps update it for "Hello, World!" (not "Hello World!")? – Tankoos