@learncard/core NPM

@learncard/core

The LearnCard Core is a pluggable, open-source, universal digital wallet to enable any individual or organization to seamlessly issue, earn, store, share, and spend currency and credentials built for the future of education and work.

Documentation

All LearnCard documentation can be found at: https://docs.learncard.com

Install

pnpm i @learncard/core

Usage

Instantiation

Instantiate a wallet using initLearnCard. This method accepts a unique identifier string that is up to 64 characters long. If it is less than 64 characters, initLearnCard will pad the start of the string with 0's until it is 64 characters long.

import { initLearnCard } from "@learncard/core";

const wallet = await initLearnCard({ seed: 'a'.repeat(64) });

Issuing/Verifying Credentials and Presentations

Issue a credential

// Grab a test VC, or create your own!
const unsignedVc = await wallet.invoke.getTestVc();

const vc = await wallet.invoke.issueCredential(unsignedVc);

Verify a credential

const result = await wallet.invoke.verifyCredential(vc, {}, true);

if (result.warnings.length > 0) console.error('Verification warnings:', result.warnings);

if (result.errors.length > 0) console.error('This credential is not valid!', result.errors);
else console.log('This credential is valid!');

Issue a presentation

const vp = await wallet.invoke.issuePresentation(vc);

Verify a presentation

const result = await wallet.invoke.verifyPresentation(vp);

if (result.warnings.length > 0) console.error('Verification warnings:', result.warnings);

if (result.errors.length > 0) console.error('This presentation is not valid!', result.errors);
else console.log('This presentation is valid!');

Storing/Retrieving/Publishing Credentials with LearnCloud

To maintain co-ownership of credentials, it is best to store credentials in a public place, and then store references to that public place. While this is not the only way to store credentials (and is also definitely not a silver bullet! E.g. credentials containing private data), it is the opinion of this library that it should be used by default.

Publish Credential

After signing a VC, you may choose to publish that credential to Ceramic. Doing so will return a stream ID, which you may share to the recipient. That stream ID can then be used to resolve the issued credential. This means both the issuer and recipient may store the stream ID instead of the credential itself.

// Issuer

const holderDid = 'did:key:z6MknqnHBn4Rx64gH4Dy1qjmaHjxFjaNG1WioKvQuXKhEKL5'
const uvc = learnCard.invoke.newCredential({ subject: holderDid });
const vc = await learnCard.invoke.issueCredential(uvc);
const uri = await learnCard.store.LearnCloud.upload(vc);

// Holder

const credential = await learnCard.read.get(uri);
const result = await learnCard.invoke.verifyCredential(credential);

if (result.errors.length == 0) {
    await learnCard.index.LearnCloud.add({ uri, id: 'test' });
}

Reading From LearnCloud

const records = await learnCard.index.LearnCloud.get();
const record = records.find(({ id }) => id === 'test');
const storedCredential = await learnCard.read.get(record.uri);

Adding a Credential to a Wallet

After receiving a streamID, you can persist that streamID by calling addCredential, and giving the credential a bespoke title

await wallet.index.LearnCloud.add({ uri, id: 'Test VC' });

This will add the streamId, which can be used to resolve the verifiable credential to IDX using the wallet's secret key. You can think of this as acting like the wallet's personal storage.

Getting a credential from the Wallet

After calling addCredential, you can use the bespoke title to retrieve that credential at any time

const record = (await wallet.index.LearnCloud.get()).find(record => record.id === 'Test VC');
const vcFromIdx = await wallet.read.get(record.uri);

Alternatively, you can get an array of all credentials you have added using getCredentials

const uris = (await wallet.index.LearnCloud.get()).map(record => record.uri);
const vcs = await Promise.all(uris.map(async uri => wallet.read.get(uri)));

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.

Who is Learning Economy Foundation?

Learning Economy Foundation (LEF) is a 501(c)(3) non-profit organization leveraging global standards and web3 protocols to bring quality skills and equal opportunity to every human on earth, and address the persistent inequities that exist around the globe in education and employment. We help you build the future of education and work with: