Chapter 5

Phase 2: API Interface

RESTful APIs enable programmatic access to fusion data, AI predictions, and control optimization across all compliant systems.

API Overview

The WIA-FUSION API provides a standardized interface for accessing fusion data, running AI predictions, and optimizing control parameters. The API uses REST principles with JSON payloads, JWT authentication, and WebSocket streaming for real-time data.

Core Endpoints

Plasma State API

// Request
POST /api/v1/plasma/state
Content-Type: application/json
Authorization: Bearer <token>

{
  "plasma_state": {
    "shot_id": "KSTAR-20240415-001",
    "timestamp": "2024-04-15T10:30:00Z",
    "reactor": "KSTAR",
    "core_parameters": {
      "temperature_keV": { "ion": 10, "electron": 10 },
      "density_m3": { "value": 1.0, "unit": "1e20/m3" }
    }
  }
}

// Response 201 Created
{
  "success": true,
  "shot_id": "KSTAR-20240415-001",
  "recorded_at": "2024-04-15T10:30:00.150Z"
}

Disruption Prediction API

// Request
POST /api/v1/fusion/predict/disruption
{
  "plasma_state": {
    "temperature_keV": 10,
    "density_m3": 1.0,
    "plasma_current_ma": 15,
    "beta_percent": 2.5
  },
  "diagnostics": {
    "mhd_amplitude": 0.3,
    "locked_mode_indicator": false
  }
}

// Response
{
  "prediction": {
    "disruption_probability": 0.15,
    "time_to_disruption_s": null,
    "confidence": 0.92,
    "risk_factors": [
      { "factor": "mhd_activity", "contribution": 0.08 },
      { "factor": "density_limit", "contribution": 0.05 }
    ],
    "recommended_actions": [
      { "action": "monitor_mhd", "priority": "medium" }
    ]
  }
}

Control Optimization API

// Request
POST /api/v1/plasma/control/optimize
{
  "current_state": {
    "temperature_keV": 10,
    "heating_power_mw": { "nbi": 30, "icrh": 10, "ecrh": 5 }
  },
  "target": {
    "q_factor": 10,
    "steady_state_duration_s": 300
  },
  "constraints": {
    "max_heating_power_mw": 50,
    "max_divertor_heat_mw_m2": 10
  }
}

// Response
{
  "optimized_control": {
    "heating_power_mw": { "nbi": 33, "icrh": 10, "ecrh": 7 },
    "predicted_performance": { "q_factor": 10.2 },
    "confidence": 0.88
  }
}

Real-time Streaming

For real-time plasma monitoring, the API provides WebSocket streaming:

// Connect to WebSocket
const ws = new WebSocket('wss://api.fusion.wia.live/v1/stream/plasma?token=<jwt>');

// Subscribe to channels
ws.send(JSON.stringify({
  action: 'subscribe',
  channels: ['plasma_state', 'stability', 'control'],
  reactor: 'KSTAR',
  sample_rate_hz: 100
}));

// Receive data
ws.onmessage = (event) => {
  const data = JSON.parse(event.data);
  console.log(`Q-factor: ${data.plasma_state.q_factor}`);
};

SDK Usage

Official SDKs are available for TypeScript, Python, and other languages:

// TypeScript SDK
import { FusionClient } from '@wia/fusion-sdk';

const client = new FusionClient({
  apiKey: process.env.WIA_FUSION_API_KEY,
  reactor: 'KSTAR'
});

// Record plasma state
await client.plasma.recordState({
  temperature_keV: { ion: 10, electron: 10 },
  density_m3: 1.0
});

// Get disruption prediction
const prediction = await client.fusion.predictDisruption({
  beta_percent: 2.5,
  mhd_amplitude: 0.3
});

console.log(`Risk: ${prediction.probability * 100}%`);