Javascript SDK For Verifiable Credentials

At the moment, this library only contains a function to interact with an Identity Provider to get a credential presentation for a user.

The flow to request a credential is performed through a browser.

Installation

Install library

``bash
npm install @dfinity/verifiable-credentials
`

The bundle needs peer dependencies, be sure that following resources are available in your project as well.

`bash
npm install @dfinity/principal
`

Import per modules:

`javascript
// import * from '@dfinity/verifiable-credentials'; // Error: use sub-imports, to ensure small app size
import { requestVerifiablePresentation } from "@dfinity/verifiable-credentials/request-verifiable-presentation";
`

Relying Party: Request Credentials

Use the function requestVerifiablePresentation to request credentials from an issuer.

$3

The function performs the following steps:

- Open a new window or tab with the Identity Provider.
- Wait for a window post message from the Identity Provider.
- Send a request to the Identity Provider through the window post message.
- Wait for the response from the Identity Provider.
- Call onSuccess callback when the flow was successful. Not necessarily that the credential was received.
- Call onError callback when the flow has some technical error or the user closes the window.

More info in the Internet Identity Specification for Verifiable Credentials.

$3

To start a flow, call the function with the expected parameters:

`javascript
requestVerifiablePresentation({
onSuccess: async (verifiablePresentation: VerifiablePresentationResponse) => {
// Called when the flow finishes successfully.
},
onError() {
// Called when there is a technical error.
},
issuerData: {
origin: "",
canisterId: "",
},
credentialData: {
credentialSpec: {
credentialType: '',
arguments: {
// Arguments to verify with the credential
},
},
credentialSubject: "",
},
identityProvider: "",
derivationOrigin: "<[optional] origin for delegated identity>",
windowOpenerFeatures: "<[optional] window opener config string>",
});
`

$3

List of properties expected in the parameter when calling the function:

- onSuccess: Function that will be called when the flow finishes. Not necessarily with the credential. This is also called if the user doesn't have the credential.
- onError: Function that will be called when the flow failes due to a technical error. Also when the user interrupts the flow.
- issuerData: Object with the origin and canisterId of the issuer.
- credentialData: Object with the subbject and the credential requested.
- identityProvider: URL of the Identity Provider. Ex: new URL("https://identity.ic0.app/").
- derivationOrigin: Indicates an origin that should be used for principal derivation. It's the same value as the one used when logging in. More info.
- windowOpenerFeatures` The flow will open a new window or tab. Pass here a configuration string to customize it.