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Quick Start Guide

Try out blindnet devkit quickly and easily.


While reading this quickstart guide you can download and follow the source code for a simple React front-end app with integrated blindnet client SDK from here.

In this quickstart guide, you will learn how to encrypt and decrypt a file using the blindnet client SDK.
We assume two users exist - a user we know, Alice, and an anonymous user Bob. For the sake of simplicity we'll act as both Alice and Bob. We will register a known user Alice to blindnet, encrypt a file to her as an anonymous user Bob, and then decrypt the file as Alice.

You will learn how to:

  • set-up the blindnet devkit
  • register Alice to blindnet
  • encrypt a file as Bob
  • decrypt a file as Alice

Before you start

Obtain blindnet authentication data. To authenticate to blindnet, your application needs the application id and application key. Application key is a cryptographic secret key which is used to sign the authentication tokens and must be kept secret (and accessible by your server).

You can get the application id and application key using the blindnet dashboard after you create a new application.


For the sake of simplicity, you can skip creating a new application and just use the following application id and key

id: 3544e7cd-64a9-41b7-88dc-397bfdaeeaf3
key: zB5IiU0xzkVdsH4NMXxrF90ZISL5kJnTHlt7h/Wbi/qVhch7Fw8J5AQ5j2PazaG5q114uApZRH4X1/kTKVx0Cw==

Be sure not to use those in production environments!

STEP 1: Set-up the SDK

In this guide, only the client SDK is needed. To generate the authentication tokens, we will use a dedicated client library. In your production environment, you will need both client and server SDKs and generate the tokens on the server side.


To install the blindnet devkit and the token generator

npm i -S @blindnet/sdk-javascript @blindnet/token-generator


Import the library to your project with

import { Blindnet } from '@blindnet/sdk-javascript'
import { createTempUserToken, createUserToken } from '@blindnet/token-generator'

Generate a user token for Alice

Tokens are used to authenticate the users of your application to blindnet. They can be used multiple times and should be regenerated when they expire using the same method.


We use the token generation library to generate the tokens. It should be only used for testing purposes and tokens should be generated on the server in production environment, after your user is authenticated.

Use the application id and key you obtained in Before you start section.

const appId = 'your_application_id'
const appKey = 'your_application_key'
const aliceId = 'alice'
const groupId = 'test-group'
const token = await createUserToken(aliceId, groupId, appId, appKey)

Specify the testing endpoint and initialize the library for Alice

const endpoint = ''
const blindnet = Blindnet.init(token, endpoint)

Connect Alice to blindnet

Blindnet can encrypt files with a particular destination (list of users or a user group) in mind. So in order to start encrypting, you first need to have some users (Alice in this case) that you've connected to blindnet.

To connect a user to blindnet, a secret value has to be provided. That value must only be known by the user (e.g. user's password). In that case, it's important not to use the same value to log-into your system and connect to blindnet for which we provide a method deriveSecrets.

const { appSecret, blindnetSecret } = await Blindnet.deriveSecrets(secret)
await blindnet.connect(blindnetSecret)

You can use appSecret as a password for the user to log-into your system.

STEP 2: Encrypt a file

After Alice has connected to blindnet, data can be encrypted for her. We will simulate an anonymous user Bob encrypting a file for Alice.

Initialize SDK for Bob

You need to initialize the library with the temporary token in order to encrypt the data. Pass the id of the group Alice belongs to in order to give permission to encrypt data for her.

const token = await createTempUserToken(groupId, appId, appKey)
const blindnet = Blindnet.init(token, endpoint)

Encrypt a file

Obtain a file from the <input type="file" id="file-pick> HTML element and pass it to the encrypt method. Add Alice as a recipient.

const file = document.getElementById('file-pick').files[0]
const { encryptedData } = await blindnet.capture(data).forUser(aliceId).encrypt()

encryptedData should be stored by you.

STEP 3: Decrypt a file

To decrypt a file, you only need encryptedData.

const { data, metadata } = await blindnet.decrypt(encryptedData)

There is a convenient library to save files file-saver.