Weather Demo Application

A GraphQL-based weather application that provides weather forecasts and travel packing tips for cities. This application uses gRPC for communication between its microservices.

Quick Start

1. Copy the environment configuration:

   cp .env.example .env

2. Start the application:

   docker-compose up

The application will run with mocked weather data and mocked assistance tips. The GraphQL endpoint will be available at http://localhost:4000.

The stream-consumer server will output console updates for specific cities to demonstrate gRPC streaming functionality.

GraphQL API

The API provides two main queries:

Query Weather Only

query Weather($city: String!) {
  weather(city: $city) {
    current {
      temperature
      condition
    }
    forecast {
      date
      maxTemp
      minTemp
      condition
    }
  }
}

Query Trip Briefing Only

query TripBriefing($city: String!) {
  tripBriefing(city: $city) {
    pack
    tips
  }
}

Query Both Weather and Trip Briefing

query Weather($city: String!) {
  tripBriefing(city: $city) {
    pack
    tips
  }
  weather(city: $city) {
    current {
      temperature
      condition
    }
    forecast {
      date
      maxTemp
      minTemp
      condition
    }
  }
}

Configuration Options

Enable Real Weather Data

To use real weather data from Open-Meteo API, uncomment the following line in your .env file:

USE_OPEN_METEO=true

Enable OpenAI Integration

To get real packing recommendations and tips powered by OpenAI, add your API key to the .env file:

OPENAI_API_KEY=your_openai_api_key_here

You can also customize the OpenAI model by setting the OPENAI_API_MODEL environment variable (defaults to gpt-5-mini):

OPENAI_API_MODEL=gpt-5

What else should be done to make an app better

To make this weather app production-ready, several improvements should be implemented:

Code Quality & Testing

• Unit Tests - Test individual functions and components
• Integration Tests - Test API endpoints and data flow
• End-to-End Tests - Test complete user workflows
• Linter + Prettier - Enforce consistent code style and catch errors
• Type Safety - Use TypeScript for better type checking
• Code Coverage - Ensure adequate test coverage

Error Handling & Validation

• Input Validation - Validate and sanitize all incoming parameters
• API Error Handling - Gracefully handle external API failures
• Rate Limiting - Prevent API abuse and respect third-party limits
• Timeout Handling - Handle slow or unresponsive external services
• Fallback Mechanisms - Use mock data when APIs fail

Security & Performance

• CORS Configuration - Proper cross-origin request handling
• Caching Strategy - Implement Redis/memory caching for API responses

Monitoring & Operations

• Logger - Integrate winston to better log output
• Health Checks - Endpoint to verify service availability