adding credentials package to web5-js

[nitro-neal]

Summary

Integrate pex SSI objects within the credentials package of web5 and provide an SSI SDK

The types.ts file in the credential package exports web5 objects as wrapped pex objects
This allows users to only need to import web5 and not pex, and we can add abstractions around pex lib as needed.

Credentials

VerifiableCredential Creation and Verification

The VerifiableCredential class provides methods for the creation, handling, and signing of Verifiable Credentials (VCs) in JWT format.

• VerifiableCredential.create: Creates a Verifiable Credential (VC) in JWT format.
• VerifiableCredential.validatePayload: Validates the structure and integrity of a Verifiable Credential payload.
• VerifiableCredential.verify: Verifies the integrity of a VC JWT.
• VerifiableCredential.decode: Decodes a VC JWT into its constituent parts: header, payload, and signature.

VP Creation and Verification

The VerifiablePresentation class provides utility methods for creation and handling Verifiable Presentations (VPs) in JWT format.

• VerifiablePresentation.create: Creates a Verifiable Presentation (VP) in JWT format from a presentation definition and set of credentials.
• VerifiablePresentation.verify: Verifies the integrity of a VP JWT.
• VerifiablePresentation.validatePayload: Validates the structure and integrity of a Verifiable Presentation payload.
• VerifiablePresentation.decode: Decodes a VP JWT into its constituent parts: header, payload, and signature.

Presentation Exchange Helpers

These methods assist in evaluating verifiable credentials and presentations against specified presentation definitions.

• VerifiableCredential.evaluateCredentials: Evaluates a set of verifiable credentials against a specified presentation definition.
• VerifiablePresentation.evaluatePresentation: Evaluates a given Verifiable Presentation against a specified presentation definition.

Verifiable Credentials and Presentations Library

Note: you do not have to use the functions to create SSI objects, you can instead create them yourselves with the boilerplate types in types.ts

      const vc: VerifiableCredentialV1 = {
        '@context'          : ['https://www.w3.org/2018/credentials/v1'],
        'id'                : 'my-cred',
        'type'              : ['VerifiableCredential'],
        'issuer'            : 'did:key:123',
        'issuanceDate'      : getCurrentXmlSchema112Timestamp(),
        'credentialSubject' : {
          'btcAddress': 'btcAddress123'
        }
      };

Signer Options Object

The Signer represents a function that takes a byte array as input and returns a promise that resolves to a byte array, representing the signature of the input data.

Type Definition

type Signer = (data: Uint8Array) => Promise<Uint8Array>;

This change also allows a full PE by users using boilerplate ssi objects. A full Presentation Exchange is available as a new unit test presentationexchange.spec.ts

[nitro-neal]

Tests Passing

[codecov]

Codecov Report

Merging #175 (15154b6) into main (150b419) will increase coverage by 0.11%.
The diff coverage is 92.77%.

@@            Coverage Diff             @@
##             main     #175      +/-   ##
==========================================
+ Coverage   89.42%   89.53%   +0.11%     
==========================================
  Files          64       67       +3     
  Lines       12399    12828     +429     
  Branches     1188     1238      +50     
==========================================
+ Hits        11088    11486     +398     
- Misses       1291     1319      +28     
- Partials       20       23       +3     

Components	Coverage Δ
api	94.32% <ø> (ø)
common	95.00% <ø> (ø)
credentials	92.77% <92.77%> (∅)
crypto	94.87% <ø> (ø)
dids	92.16% <ø> (ø)
agent	87.80% <ø> (ø)
identity-agent	59.05% <ø> (ø)
proxy-agent	58.59% <ø> (ø)
user-agent	57.36% <ø> (ø)

[frankhinek]

Notes:

• Switched to using Convert utility from the @web5/common package instead of Encoder from @tbd54566975/dwn-sdk-js.
• A devDependency on @tbd54566975/dwn-sdk-js was added to the PresentationExchange test but not added to package.json. Doesn't need to be fixed since it was swapped for Convert but something to keep an eye on.

And a a few minor changes:

• Added comments to the newly added utility functions. @nitro-neal double-check that the explanations and usage examples are accurate.
• Used exact dependency version for @sphereon/pex.
• Updated formatting, word wrap, and code style to match SDK conventions.

[mistermoe]

🎖️ 💯 🍖 🌞

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