Weather Notifier — Real-Time Shell Scripting Exercise

weather-notifier.md

🌤️ Weather Notifier — Real-Time Shell Scripting Exercise

⏱ Duration: 30 minutes

📍 Location: Pune

🧪 Tools: Bash, curl, awk, cron, Open Source API (wttr.in)

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🎯 Exercise Goal

Write a Bash script that:

• Fetches current weather in Pune from a public API
• Extracts the weather condition and temperature
• Logs personalized advice (e.g., “Carry umbrella ☔” or “Wear sunscreen 😎”)
• Runs every hour automatically using cron

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🛠 How to Run the Script

1. Make the script executable:

   chmod +x weather_notify.sh

2. Run it manually:

   ./weather_notify.sh

3. Check the weather log:

   cat ~/weather.log

4. Schedule it to run every hour using cron:

   crontab -e

   Add this line:

   0 * * * * /full/path/to/weather_notify.sh

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🧪 Sample Log Output

[2025-07-12 13:00] Pune: Sunny +34°C — Wear sunglasses 😎 and sunscreen 🧴
[2025-07-12 14:00] Pune: Light rain +28°C — Carry an umbrella ☔

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📚 Learning Outcomes

Feature	Real-Life Use Case
curl	Consuming APIs in scripts
awk, case	Text parsing + conditional logic
cron	Background scheduling for automation
Logging	Creating traceable audit reports

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💡 Optional Extensions

• Monitor weather in multiple cities with a loop
• Use notify-send for desktop notifications (Linux GUI)
• Send messages via Telegram bot or Slack webhook
• Add sound alerts for rain using aplay or mpg123

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✅ Why This Matters

This script introduces you to API integration and job scheduling — two key building blocks in automation, DevOps, and real-time alerting systems.

“The same tools used to monitor a Kubernetes cluster can help you decide when to carry a raincoat.” ☔

weather_notify.sh

#!/bin/bash
# weather_notify.sh — logs weather advice based on real Pune weather

CITY="Pune"
DATA=$(curl -s "wttr.in/$CITY?format=%C+%t")

# Extract weather condition and temperature
CONDITION=$(echo "$DATA" | awk '{$NF=""; print $0}' | sed 's/ *$//')
TEMP=$(echo "$DATA" | awk '{print $NF}')

# Create advice based on condition
if [[ "$CONDITION" == *"Rain"* || "$CONDITION" == *"Shower"* || "$CONDITION" == *"Thunder"* ]]; then
  ADVICE="Carry an umbrella ☔"
elif [[ "$CONDITION" == *"Sunny"* || "$CONDITION" == *"Clear"* ]]; then
  ADVICE="Wear sunglasses 😎 and sunscreen 🧴"
elif [[ "$CONDITION" == *"Cloudy"* || "$CONDITION" == *"Overcast"* ]]; then
  ADVICE="A bit gloomy – light jacket maybe? 🧥"
else
  ADVICE="Be weather-wise! 📡"
fi

# Log to file
echo "[$(date '+%Y-%m-%d %H:%M')] $CITY: $CONDITION $TEMP — $ADVICE" >> ~/weather.log