_{観察する ・ 構築する ・ 応答する}

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THE RESPONSE SYSTEM KYŪKYŪ — EMERGENCY RESPONSE Where technology meets urgency. Where every second becomes a decision. A production-ready emergency dispatch platform that connects citizens, ambulance drivers, hospitals, dispatchers and administrators through real-time coordination. → ENTER THE SYSTEM

01 — 観察する OBSERVE See the emergency as it unfolds. 02 — 構築する BUILD Route, dispatch and coordinate. 03 — 研究する RESEARCH Measure what the system is doing. 04 — 応答する RESPOND Move the right resource, fast. 05 — 余白 BEYOND Design for the failure nobody planned for.

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01 · 観察する · OBSERVE

Understand the emergency before the system responds.

What is this?

The Emergency Response System (ERS) is a real-time dispatch platform designed to reduce the time between an emergency request and coordinated medical response.

The platform supports one-click emergency requests, GPS-based ambulance discovery, automated dispatch, real-time tracking, ETA updates, hospital coordination, medical records, notifications and operational analytics.

The response loop

┌──────────┐       ┌────────────┐       ┌────────────┐
│  CITIZEN │ ───→  │   DISPATCH │ ───→  │  AMBULANCE │
└──────────┘       └────────────┘       └─────┬──────┘
      ↑                    │                  │
      │                    ↓                  ↓
      │             ┌────────────┐      ┌────────────┐
      └──────────── │  HOSPITAL  │ ←─── │ REAL-TIME  │
                    └────────────┘      │  TRACKING  │
                                        └────────────┘

Core capabilities

System	Capability
SOS	Create and manage emergency requests
DISPATCH	Priority-based ambulance allocation
GPS	Live ambulance location and distance calculation
ETA	Road-network ETA with routing fallback
TRACKING	Real-time status and location updates
HOSPITAL	Request acceptance and patient coordination
MEDICAL	Secure medical record upload and sharing
ANALYTICS	Performance, latency and operational metrics
ALERTING	Slack, email and webhook system alerts

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02 · 構築する · BUILD

Engineering the path from SOS to care.

Architecture

                         ┌──────────────────────┐
                         │       CLIENTS        │
                         │ Citizen · Driver     │
                         │ Hospital · Admin     │
                         └──────────┬───────────┘
                                    │
                              HTTP / WebSocket
                                    │
                         ┌──────────▼───────────┐
                         │   EXPRESS / NODE.JS  │
                         │  Auth · Routes · API │
                         └──────────┬───────────┘
                                    │
              ┌─────────────────────┼─────────────────────┐
              │                     │                     │
       ┌──────▼──────┐      ┌──────▼──────┐      ┌──────▼──────┐
       │  DISPATCH   │      │   REALTIME  │      │  ANALYTICS  │
       │ Engine/Queue│      │ Socket.IO   │      │ Metrics     │
       └──────┬──────┘      └──────┬──────┘      └──────┬──────┘
              │                     │                     │
              └─────────────────────┼─────────────────────┘
                                    │
                    ┌───────────────┼───────────────┐
                    │                               │
             ┌──────▼──────┐                 ┌──────▼──────┐
             │   MongoDB   │                 │    Redis    │
             │ Persistence │                 │ Queue/Cache │
             └─────────────┘                 └─────────────┘

Project structure

Ambulance/
├── controllers/          # Auth, emergency, dispatch, ambulance, admin, analytics
├── middleware/           # JWT, RBAC, validation, sessions, uploads, errors
├── models/               # User, Ambulance, EmergencyRequest, Hospital, MedicalRecord
├── routes/               # Domain-specific API routers
├── utils/                # Dispatch engine, ETA, queues, caching, monitoring
├── public/                # Citizen, driver, hospital and admin interfaces
├── tests/                 # Unit, integration, security and system tests
├── scripts/               # Load tests, migrations and validation utilities
├── config/                # Swagger and application configuration
├── server.js              # Application/server integration
├── index.js               # Application bootstrap
├── docker-compose.yml     # Container orchestration
├── dockerfile             # Production container image
└── README.md              # You are here

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03 · 研究する · RESEARCH

Measure the system. Find the bottleneck. Improve the response.

Technology stack

Layer	Technologies
Runtime	Node.js 18+
API	Express.js
Database	MongoDB · Mongoose
Realtime	Socket.IO
Cache / Queue	Redis · BullMQ
Authentication	JWT · httpOnly cookies · bcrypt
Routing	OSRM · Haversine fallback
Uploads	Multer · Cloudinary
Notifications	Nodemailer · Twilio · Slack/Webhooks
Observability	Winston · Prometheus metrics
Security	Helmet · CORS · MongoDB sanitization · rate limiting
Testing	Jest · Supertest · MongoDB Memory Server
Deployment	Docker · Nginx · Render-ready configuration

Dispatch intelligence

The dispatch layer combines distance, availability, priority and ambulance state to determine an appropriate response path. Geospatial calculations use the Haversine formula, while ETA calculation can use road-network routing and fall back when routing is unavailable.

Resilience by design

           NORMAL LOAD
               │
               ▼
        ┌──────────────┐
        │ Dispatch     │
        │ Queue        │
        └──────┬───────┘
               │
        ┌──────▼───────┐
        │ Available    │
        │ Ambulance    │
        └──────────────┘

        HIGH LOAD / FAILURE
               │
        ┌──────▼────────┐
        │ Rate Limiter  │
        ├───────────────┤
        │ Load Shedder  │
        ├───────────────┤
        │ Circuit Break │
        ├───────────────┤
        │ Retry / Queue │
        └───────────────┘

Security model

• JWT authentication with revocation support
• httpOnly + SameSite: Strict cookies
• Role-based access control across protected routes
• Password hashing with bcrypt
• Helmet security headers
• CORS controls
• Input and coordinate validation
• Pagination limits and analytics export caps
• Rate limiting against abusive request volume
• Immutable audit logging for sensitive operations

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04 · 応答する · RESPOND

From a citizen's SOS to a completed emergency request.

01 · REQUEST

A citizen creates an emergency request through the public interface.

02 · LOCATE

The system receives the emergency coordinates and evaluates available response resources.

03 · DISPATCH

The dispatch engine and queue determine an appropriate ambulance response.

04 · ACCEPT

The driver receives the assignment and can accept or reject the response.

05 · TRACK

Ambulance location and response state can be updated in real time through Socket.IO-backed coordination.

06 · ARRIVE

The patient is transported while ETA and emergency state remain visible to the relevant roles.

07 · COMPLETE

The driver completes the request and the system retains operational history for later analysis.

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Role matrix

Role	Responsibility
CITIZEN	Create emergencies, track requests, view history and manage own medical records
DRIVER	Receive assignments, update ambulance status and GPS location
HOSPITAL	Accept emergency requests and access shared patient records
DISPATCHER	Monitor requests and ambulances, manage dispatch operations
ADMIN	User management, system oversight and analytics

CITIZEN, DRIVER and HOSPITAL can self-register. DISPATCHER and ADMIN roles require administrative assignment.

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API surface

Authentication · /api/auth

Method	Endpoint	Purpose
POST	/register	Register user
POST	/login	Login with email or phone
GET	/me	Current user
POST	/logout	Revoke session
POST	/refresh	Refresh JWT

Emergency · /api/emergency

Method	Endpoint	Purpose
POST	/	Create SOS request
GET	/	List role-filtered requests
GET	/history	Citizen request history
GET	/:id	Retrieve emergency
PUT	/:id/accept	Hospital accepts request
PUT	/:id/complete	Driver completes request

Dispatch · /api/dispatch

Method	Endpoint	Purpose
POST	/request	Create and auto-dispatch emergency
GET	/active	Current active request
GET	/assignments	Driver assignments
PUT	/:id/response	Accept/reject assignment
PATCH	/:id/track	Update location/status
DELETE	/:id	Cancel request

Ambulances · /api/ambulances

Method	Endpoint	Purpose
POST	/	Register/update ambulance
GET	/	List ambulances
GET	/:id	Retrieve ambulance
PATCH	/:id/status	Update ambulance status
PATCH	/:id/location	Update GPS location

Admin · /api/admin

Method	Endpoint	Purpose
GET	/users	List users
GET	/users/:id	Retrieve user
PUT	/users/:id/role	Change role
DELETE	/users/:id	Delete user
GET	/ambulances	List ambulances
GET	/stats	System statistics

Analytics · /api/analytics

Method	Endpoint	Purpose
GET	/latency	Response latency
GET	/performance	Daily performance
GET	/export	JSON/CSV export with row cap

Medical Records · /api/medical

Method	Endpoint	Purpose
POST	/upload	Upload medical file
GET	/:userId	Retrieve records
GET	/record/:id	Retrieve one record
DELETE	/record/:id	Delete record
POST	/share/:recordId	Share with hospital

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05 · 余白 · BEYOND

The system should remain useful when the situation stops being predictable.

Production observability

REQUEST RATE ────────┐
ERROR RATE ──────────┤
P50 / P95 / P99 ─────┤
QUEUE DEPTH ─────────┼──→ METRICS DASHBOARD
MEMORY / CPU ────────┤
DB HEALTH ───────────┘

Live metrics are available at:

/metrics-dashboard

Health and readiness endpoints:

curl http://localhost:3000/health
curl http://localhost:3000/ready

Load testing

# Default load test
npm run test:load

# 100 simulated users · 60 seconds
npm run test:load:quick

# 1000 simulated users · 5 minutes
npm run test:load:full

Tests

The repository includes unit, integration, system and security coverage.

npm test
npm run test:integration
npm run test:all
npm run test:cov
npm run lint

Deployment

# Install
npm install

# Development
npm run dev

# Production
npm start

Docker:

docker build -t ers:latest .
docker-compose up -d

Environment

Variable	Required	Purpose
MONGODB_URI	✅	MongoDB connection
JWT_SECRET	✅	JWT signing secret
JWT_EXPIRE	—	Token lifetime; defaults to 7d
PORT	—	HTTP port; defaults to 3000
NODE_ENV	—	development / production
REDIS_URL	—	Redis connection for multi-instance operation
CLOUDINARY_CLOUD_NAME	—	Medical file storage
CLOUDINARY_API_KEY	—	Cloudinary authentication
CLOUDINARY_API_SECRET	—	Cloudinary authentication
OSRM_ROUTING_URL	—	Road-network routing endpoint
FRONTEND_URL	—	CORS origin

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SYSTEM NOTES

Additional engineering documentation lives in:

• SYSTEM_VISION.md — system mission and scale blueprint
• API_DOCS.md — API documentation
• REALTIME_TRACKING.md — real-time tracking architecture
• PERFORMANCE_OPTIMIZATIONS.md — performance work
• PRODUCTION_AUDIT.md — production audit and hardening
• DEPLOYMENT_GUIDE.md — deployment guidance

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現在観察中 · NOW OBSERVING

Emergency response is not just about speed.
It is about making the right decision when time is disappearing.

_{救急 · 構築する · 観察する · 応答する}

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