Known Issuer Registry Client (@digitalcredentials/issuer-registry-client)

Isomorphic client for fetching Known Issuer/Known Verifier registries for Node, browser and React Native.

Table of Contents

• Background
• Security
• Install
• Usage
• Contribute
• License

Background

This is a client library for loading Known Issuer or Known Verifier Registries, which are essentially dictionaries of DIDs, containing information on known issuers and verifiers.

The format of these registries is temporary, while the Verifiable Issuers and Verifiers spec is being incubated in the W3C CCG.

Security

Assumes the loaded registries are public, accessible via https.

Note that an individual DID can appear in multiple registries. Because of that, the order of registries loaded matters. For example, given a registry:

const knownRegistries = [{
    "name": "DCC Pilot Registry",
    "url": "https://digitalcredentials.github.io/issuer-registry/registry.json"
  },
  {
    "name": "DCC Sandbox Registry",
    "url": "https://digitalcredentials.github.io/sandbox-registry/registry.json"
  }]

If an issuer DID is contained in both of those registries, the issuer entry (that contains the issuer name and URL) will come from the first registry, "DCC Pilot Registry".

In other words, verifiers and other implementers must order the registries in order of most authoritative to least.

Install

• Node.js 18+ is recommended.

NPM

To install via NPM:

npm install @digitalcredentials/issuer-registry-client

Development

To install locally (for development):

git clone https://github.com/digitalcredentials/issuer-registry-client.git
cd issuer-registry-client
npm install

Usage

First, put together an array of known issuer and verifier registries you would like to check against:

const knownRegistries = [
  {
    "name": "DCC Pilot Registry",
    "url": "https://digitalcredentials.github.io/issuer-registry/registry.json"
  },
  {
    "name": "DCC Sandbox Registry",
    "url": "https://digitalcredentials.github.io/sandbox-registry/registry.json"
  },
  {
    "name": "DCC Community Registry",
    "url": "https://digitalcredentials.github.io/community-registry/registry.json"
  },
  {
    "name": "DCC Registry",
    "url": "https://digitalcredentials.github.io/dcc-registry/registry.json"
  }
]

You can now:

import { RegistryClient } from '@digitalcredentials/issuer-registry-client'

const registries = new RegistryClient()

// Load the registries from the web (typically done at app startup).
await registries.load({ config: knownRegistries })

// You can now query to see if a DID is known in any registry
console.log(registries.didEntry('did:key:z6MkpLDL3RoAoMRTwTgo3rs39ZwssfaPKtGdZw7AGRN7CK4W'))
/**
DidMapRegistryEntry {
  name: 'My University',
  url: 'https://digitalcredentials.mit.edu',
  location: 'Cambridge, MA, USA',
  inRegistries: Set(2) {
    {
      name: 'DCC Community Registry',
      url: 'https://digitalcredentials.github.io/community-registry/registry.json',
      rawContents: [Object]
    },
    {
      name: 'DCC Sandbox Registry',
      url: 'https://digitalcredentials.github.io/sandbox-registry/registry.json',
      rawContents: [Object]
    }
  }
}
 */

registries.didEntry('did:example:does-not-exist')
// undefined

Contribute

PRs accepted.

If editing the Readme, please conform to the standard-readme specification.

License

MIT License © 2022 Digital Credentials Consortium.