License Server Administration

Shardian solvers validate license status at initialization against a secure licensing server. This page details the database schema, administrative API endpoints, systemd services, and the CLI key management tool.

1. Database Schema

The license server uses a lightweight, transactional SQLite database (licenses.db) located in the root of the server runtime path.

erDiagram
    LICENSES {
        string api_key PK
        string scope "both | aero | atmos"
        integer active "1 = active, 0 = revoked"
        datetime expires_at
        datetime created_at
    }

Table: `licenses`

api_key (TEXT, Primary Key): The cryptographically secure API key string prefixed with sk_live_shardian_.
scope (TEXT): Defines the products the license is authorized to run (aero, atmos, or both).
active (INTEGER): Actively toggled status. Set to 1 for active, 0 for revoked.
expires_at (DATETIME): Expiration timestamp. Pings after this time will return HTTP 401.
created_at (DATETIME): Registration timestamp.

2. API Endpoints

The license server exposes two primary groups of API endpoints:

A. Solver Verification (Public)

Used by OpenFOAM and WRF during boundary-layer/turbulence model initialization.

GET /v1/verify

Headers: Authorization: Bearer <api_key>

Response (200 OK):

{"status":"valid","key":"sk_live_shardian_...","scope":"both","expires_at":"2027-06-15T00:00:00Z"}

Response (401 Unauthorized):

{"status":"invalid","reason":"Key expired or does not exist"}

B. Administrative API (Private / Internal-Only)

Protected by basic authentication and restricted to loopback (127.0.0.1) or trusted internal networks.

POST /v1/admin/keys

Description: Creates and registers a new license key.
Body:
```
{"scope": "both", "days_valid": 180}
```

Response (200 OK):

{"key": "sk_live_shardian_aero_atmos_2026_eval_abcdef", "status": "active"}

DELETE /v1/admin/keys
- Description: Instantly revokes an active key.
- Body:
```
{"key": "sk_live_shardian_..."}
```

3. The CLI Key Management Tool

Developers can manage license keys on the VPS host using the compiled Go CLI utility license-cli:

Generating a New Key:

./license-cli create --scope both --days 365

Output:

License Key Generated Successfully!
Key:    sk_live_shardian_cfd_atmos_2026_eval_4a2c91
Scope:  both
Expiry: 2027-06-15 12:00:00 UTC
Status: Registered in licenses.db (active)

Revoking a Key:

./license-cli revoke --key sk_live_shardian_cfd_atmos_2026_eval_4a2c91