SSI Types

The ssi-types package provides foundational TypeScript types and interfaces for Self-Sovereign Identity (SSI) systems. It defines common data structures, cryptographic interfaces, and type definitions used across the SSI SDK ecosystem.

Installation

Install the package via NPM:

npm install @blockialabs/ssi-types

Key Components

Core Types

• KeyFormat: Supported key formats ('JWK' | 'Raw')
• KeyType: Supported cryptographic key types ('JsonWebKey' | 'Ed25519' | 'Secp256k1')
• Signature: Union type for signature representations
• JWK: JSON Web Key format specification

Interfaces

• ISignatureProvider: Interface for cryptographic signing and verification operations

Basic Usage

Implementing ISignatureProvider

import { ISignatureProvider } from '@blockialabs/ssi-types';

class CustomSignatureProvider implements ISignatureProvider {
  async sign(
    message: Uint8Array | string,
    publicKey: Uint8Array | string | bigint,
    options?: Record<string, unknown>,
  ): Promise<string> {
    // Custom signing implementation
    // Return signature as string (base64/hex)
    return 'signature-string';
  }

  async verify(
    signature: Uint8Array,
    message: Uint8Array,
    publicKey: Uint8Array,
    options?: Record<string, unknown>,
  ): Promise<boolean> {
    // Custom verification implementation
    // Return true if signature is valid
    return true;
  }
}

Using Signature Providers

// Create provider instance
const provider = new CustomSignatureProvider();

// Sign a message
const message = new TextEncoder().encode('Hello, World!');
const signature = await provider.sign(message, privateKey);

// Verify a signature
const isValid = await provider.verify(signature, message, publicKey);

Integration Examples

With SSI Credentials

import { ISignatureProvider } from '@blockialabs/ssi-types';
import { CredentialProcessor } from '@blockialabs/ssi-credentials';

// Configure credential processor with signature providers
const processor = new CredentialProcessor({
  // ... other config
  signatureProviders: {
    customProvider: CustomSignatureProvider,
  },
});

With SSI DID

import { ISignatureProvider } from '@blockialabs/ssi-types';
import { DIDOrchestrator } from '@blockialabs/ssi-did';

// Configure DID orchestrator with signature providers
const orchestrator = new DIDOrchestrator({
  methodRegistry,
  resolverRegistry,
  signatureProviders: {
    customProvider: CustomSignatureProvider,
  },
});

Building

Run nx build ssi-types to build the library.

Running unit tests

Run nx test ssi-types to execute the unit tests via Jest.

Running lint

Run nx lint ssi-types to check if there are lint errors.

See LICENSE.