# Python Weather App

This utility fetches current weather data for a specific city using the OpenWeatherMap API. It demonstrates how to make API calls with parameters, handle JSON responses, and manage HTTP errors.

**Modules Used:**
*   [[programming/python/modules/requests-module|requests]]: To send HTTP requests to the weather API.
*   [[programming/python/modules/argparse-module|argparse]]: To handle city input and API key from the command line.
*   [[programming/python/modules/json-module|json]]: Implicitly used by `requests` to parse the response.

## Prerequisites

You need a free API key from OpenWeatherMap.

## The Code

Save this as `weather.py`.

```python
import argparse
import requests
import sys

def get_weather(city, api_key):
    # OpenWeatherMap API endpoint
    url = "http://api.openweathermap.org/data/2.5/weather"
    
    params = {
        'q': city,
        'appid': api_key,
        'units': 'metric' # Use 'imperial' for Fahrenheit
    }
    
    try:
        print(f"Fetching weather for {city}...")
        response = requests.get(url, params=params)
        response.raise_for_status() # Raise exception for 4xx/5xx errors
        
        data = response.json()
        
        # Extract relevant info
        weather_desc = data['weather'][0]['description']
        temp = data['main']['temp']
        humidity = data['main']['humidity']
        wind_speed = data['wind']['speed']
        city_name = data['name']
        country = data['sys']['country']
        
        print(f"\n--- Weather in {city_name}, {country} ---")
        print(f"Condition:   {weather_desc.capitalize()}")
        print(f"Temperature: {temp}°C")
        print(f"Humidity:    {humidity}%")
        print(f"Wind Speed:  {wind_speed} m/s")
        
    except requests.exceptions.HTTPError as e:
        if response.status_code == 404:
            print(f"Error: City '{city}' not found.")
        elif response.status_code == 401:
            print("Error: Invalid API Key. Please check your credentials.")
        else:
            print(f"HTTP Error: {e}")
    except requests.exceptions.RequestException as e:
        print(f"Connection Error: {e}")

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="CLI Weather App")
    parser.add_argument("city", help="Name of the city")
    parser.add_argument("--api-key", required=True, help="Your OpenWeatherMap API Key")
    
    args = parser.parse_args()
    
    get_weather(args.city, args.api_key)
```

## Usage

```bash
python weather.py London --api-key YOUR_ACTUAL_API_KEY
```

[[programming/python/python]]