ula-vc-data-management


A ULA Holder plugin, responsible for storing and retrieving Verifiable Credentials and address data from a self defined data source.
This plugin also translates Verifiable Credentials to the shared data model.

Installation

In an existing project (with package.json), install ula-vc-data-management

``bash
npm install ula-vc-data-management --save
`

Usage

The following data-storage interface must be implemented to store the data on the medium of your choice:

`typescript
interface DataStorage {
get (key: string): Promise
set (key: string, value: any): Promise
remove (key: string): Promise
}
`

Currently the vcDataManagement plugin accepts the following message types:

- save-vcs: Store Verified Credentials
- get-vcs-by-context: Retrieve Verified Credentials based on a regular expression matching the context field
- get-vcs-by-subject: Retrieve Verified Credentials based on a regular expression matching the CredentialSubject key
- save-address: Store an address and its details (accountId, keyId, predicate)
- save-vc-transaction: Save a VC transaction object
- get-address-details: Get the address details (accountId, keyId, predicate)
- get-attestations: Get all attestations (conform the shared data model)
- get-attestors: Get all attestors (conform the shared data model)
- get-transactions: Get all transaction (conform the shared data model)
- get-new-key-id: Receive a unique unused keyId (to create a unique address)
- data-clear-all: Clear all Verifiable Credentials

`typescript
import {
AddressRepository,
VcDataManagement,
VerifiableCredentialRepository
} from 'ula-vc-data-management'
import {
EventHandler,
Message
} from 'universal-ledger-agent'

// Assume an implementation of DataStorage at 'my-data-storage'
import { MyDataStorage } from 'my-data-storage'
const myDataStorage = new MyDataStorage()

// Create instances for the address - and VC repositories
const addressRepo = new AddressRepository(myDataStorage)
const vcRepo = new VerifiableCredentialRepository(myDataStorage)

// Create the vcDataManagement instance
let vcDataManagement = new VcDataManagement(vcRepo, addressRepo)

// Create an array of plugins, now it's only vcDataManagement
const plugins = [ vcDataManagement ]

// Initialize the ULA with the plugins
const eventHandler = new EventHandler(plugins)

// Example: Store an address
const testAddress = {
address: '0x3f8C962eb167aD2f80C72b5F933511CcDF0719D4',
accountId: 101,
keyId: 532,
predicate: 'https://schema.org/givenName'
}

// define the ULA message, to save address details
const message = new Message({
type: 'save-address',
address: testAddress
})

// Offer the message to the ULA. For this message implementation,
// no callback is used in this case so the parameter undefined
eventHandler.processMessage(message, undefined)
`

Running tests

Besides unit testing with Mocha, the effectivity of all tests are also measured with the Stryker mutation testing framework.

`bash
npm run test
npm run stryker
``

We aim to achieve a coverage of 100%. Stryker and/or mocha test scores below 80% will fail the build.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

License and disclaimer

apache-2.0 with a notice.

We discourage the use of this work in production environments as it is in active development and not mature enough.