Browser DNA Express Tables is a tool for consuming DNA Express Fingerprint objects and storing them in SQL database

Usage no npm install needed!

<script type="module">
  import ch1BrowserDnaExpressTables from 'https://cdn.skypack.dev/@ch1/browser-dna-express-tables';


CH1 Browser DNA Express Tables


This is not well maintained


yarn add @ch1/browser-dna-express-tables

What is This

Fingerprinting middleware for express. This middleware works with @ch1/browser-dna-express and stores its fingerpritns in a sql database

Morality of Browser Fingerprinting

Fingerprinting can be a hot button topic and for good reason. Privacy on the internet is an illusion. We should expect some modicum of privacy but we should also be aware of the limitations of the tools we use. This library and other - more robust - libraries like Panopticlick show just how much trivial seeming data we give away that actually "marks" us.

Ultimately your fingerprint from a library like this, in combination with an IP address is not really enough to uniquely identify most people but it really shrinks the pool, especially in certain areas.

Why Would We Want This?

While we want and should have privacy there is a strong use case for having our connections be semi-identifiable.

Consider the following:

  • You run a web service of some sort
  • You're getting a lot of connections from one IP
  • The IP represents a huge institution that has a lot of legitimate users but due to NAT they all appear as one user

This is where at least fingerprinting headers and connection detail server side helps.

Another case would be implementing an app that uses semi-anonymous sharing having a JS + server side fingerprint would allow the app to somewhat distinguish anonymous connections for the purpose of say short term chat.


Use at the top level of an express app

import { fingerprint } from '@ch1/browser-dna-express';
import { fingerprintStore, schema } from '@ch1/browser-dna-express-tables';
import { create as createSql } from '@ch1/sql-tables';

const sql = createSql(/* db connection config */, {
  /* custom schema here */

// where app is your express app

This should store fingerprint data on every request, which is really expensive.