CHLOM License Exchange (LEX) — API Design Specification (Phase 3→4)

Owner: CrownThrive, LLC Date: 2025-08-08 Classification: Internal — API Design, Endpoints, and Integration Standards

1. Purpose

This document defines the REST and gRPC API design for the CHLOM License Exchange (LEX), ensuring interoperability between on-chain smart contracts, off-chain compliance services, marketplaces, and DAO governance systems. It provides endpoint definitions, request/response schemas, authentication mechanisms, and developer integration guidelines.

2. API Gateway Overview

  • Protocol Support: HTTPS (REST), HTTP/2 (gRPC), WebSockets for event streams.
  • Gateway Location:
  • API Versioning:
  • Load Balancing: NGINX with Envoy proxy for routing and rate limiting.

3. Core API Modules

  • License Management API — Issue, renew, revoke, transfer, and query licenses.
  • Compliance API — Fetch compliance scores, run real-time checks, and verify ZKPs.
  • Marketplace API — List, search, and settle license trades.
  • Governance API — Submit proposals, vote, and query DAO state.
  • Treasury API — Query balances, transaction history, and staking rewards.

4. REST Endpoints (Sample)

POST /v1/licenses/issue
POST /v1/licenses/renew/{licenseId}
POST /v1/licenses/revoke/{licenseId}
GET  /v1/licenses/{licenseId}
POST /v1/compliance/score
POST /v1/compliance/verify-zkp
GET  /v1/marketplace/listings
POST /v1/marketplace/create
POST /v1/governance/proposals
POST /v1/governance/vote
GET  /v1/treasury/balance

5. gRPC Service Definitions

service LicenseService {
  rpc IssueLicense (IssueLicenseRequest) returns (LicenseResponse);
  rpc RenewLicense (RenewLicenseRequest) returns (LicenseResponse);
  rpc RevokeLicense (RevokeLicenseRequest) returns (LicenseResponse);
  rpc GetLicense (GetLicenseRequest) returns (LicenseResponse);
}

service ComplianceService {
  rpc GetComplianceScore (ComplianceScoreRequest) returns (ComplianceScoreResponse);
  rpc VerifyZKP (ZKPVerifyRequest) returns (ZKPVerifyResponse);
}

6. Authentication & Authorization

  • OAuth 2.0 Client Credentials for trusted apps.
  • mTLS for issuer-to-API secure connections.
  • JWT Claims for fine-grained permissions.
  • Rate Limits: Default 1000 req/min per API key, adjustable by DAO governance.

7. Event Streaming

  • WebSockets/SSE for license lifecycle events.
  • Event Types:

8. Error Handling

  • Standardized error codes:
  • JSON error structure: 
{
  "error_code": "LEX-ERR-1001",
  "message": "License not found",
  "details": {}
}

9. Developer Guidelines

  • SDKs: Available in Rust, Python, JavaScript.
  • Testing Sandbox:
  • Monitoring: API metrics exposed via

This API design ensures seamless integration between CHLOM's on-chain and off-chain components, enabling rapid development and secure, scalable access to all LEX services.

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CHLOM License Exchange (LEX) — Compliance & Regulatory Integration Module Specification (Phase 3→4)