TypeScript/JavaScript SDK

[sunilp]

Summary

LDP needs a TypeScript/JavaScript SDK for the web and Node.js ecosystem. This is the second most important SDK after Python.

What to do

1. Create sdk/typescript/ with a proper npm package structure
2. Implement TypeScript types for all protocol types (matching Python SDK 1:1):
   • LdpIdentityCard, LdpCapability, QualityMetrics
   • PayloadMode, TrustDomain, Provenance
   • LdpEnvelope, LdpMessageBody
   • SessionConfig, LdpSession
3. Implement LdpClient with fetch-based HTTP client
4. Implement LdpRouter with quality/cost/latency/balanced strategies
5. Add tests with vitest or jest

Package structure

sdk/typescript/
├── package.json
├── tsconfig.json
├── src/
│   ├── index.ts
│   ├── types/
│   │   ├── identity.ts
│   │   ├── capability.ts
│   │   ├── messages.ts
│   │   ├── payload.ts
│   │   ├── provenance.ts
│   │   ├── session.ts
│   │   └── trust.ts
│   ├── client.ts
│   └── router.ts
└── tests/

Why this matters

The web/Node.js ecosystem is huge. A TypeScript SDK unlocks: browser-based LDP clients, Next.js/Express server delegates, Cloudflare Worker delegates, and Deno/Bun compatibility.

References

• Python SDK (reference): sdk/python/src/ldp_protocol/
• A2A's TypeScript SDK: https://github.com/a2aproject/a2a-js (480 stars)

Acceptance criteria

• Types match the Python SDK 1:1
• LdpClient with discover, session management, submit_task
• LdpRouter with 4 routing strategies
• Published to npm as ldp-protocol
• Tests passing