Real-World Examples

Scenario: You have a daily backup script that runs at 2 AM and should complete within 30 minutes.

Setup:

• Interval: 1440 minutes (24 hours)
• Grace Period: 30 minutes
• Expected check-in: Around 2:30 AM daily

Implementation:

#!/bin/bash
# backup_script.sh
rsync -av /data/ /backup/
if [ $? -eq 0 ]; then
    curl -X POST "https://silentcanary.com/checkin/YOUR_TOKEN" \
         -d "message=Backup completed successfully - $(du -sh /backup/ | cut -f1) backed up"
else
    # Backup failed - don't check in, let SilentCanary alert
    echo "Backup failed"
    exit 1
fi

Scenario: Monitor a critical web service that should be checked every 5 minutes.

Setup:

• Interval: 5 minutes
• Grace Period: 2 minutes
• Smart Alerts: Enabled with high sensitivity

Implementation (Python):

import requests
import time
import json

def health_check():
    try:
        # Check your service
        response = requests.get('https://your-service.com/health', timeout=10)
        if response.status_code == 200:
            # Service is healthy, check in with status
            check_in_data = {
                "message": f"Service healthy - Response time: {response.elapsed.total_seconds():.2f}s"
            }
            requests.post('https://silentcanary.com/checkin/YOUR_TOKEN', 
                         json=check_in_data)
        else:
            # Service returned error - don't check in
            print(f"Service unhealthy: {response.status_code}")
    except Exception as e:
        print(f"Health check failed: {e}")

# Run every 5 minutes
while True:
    health_check()
    time.sleep(300)  # 5 minutes

Scenario: Weekly database cleanup that runs every Sunday at 3 AM.

Setup:

• Interval: 10080 minutes (7 days)
• Grace Period: 60 minutes
• Alert Type: Email + Slack

Implementation (SQL + curl):

-- db_cleanup.sql
DELETE FROM logs WHERE created_at < DATE_SUB(NOW(), INTERVAL 90 DAY);
DELETE FROM temp_files WHERE created_at < DATE_SUB(NOW(), INTERVAL 7 DAY);
OPTIMIZE TABLE logs, temp_files;

-- Shell script
#!/bin/bash
ROWS_DELETED=$(mysql -u user -p database < db_cleanup.sql 2>&1 | grep -o '[0-9]* rows affected' | head -1)

curl -X POST "https://silentcanary.com/checkin/YOUR_TOKEN" \
     -H "Content-Type: application/json" \
     -d "{\"message\": \"DB cleanup completed - $ROWS_DELETED\"}"

Scenario: Monitor IoT sensors that should report data every 10 minutes.

Setup:

• Interval: 10 minutes
• Grace Period: 5 minutes
• Smart Alerts: Enabled to detect irregular patterns

Implementation (Arduino/ESP32):

#include <WiFi.h>
#include <HTTPClient.h>

void sendSensorData() {
  float temperature = readTemperature();
  float humidity = readHumidity();
  
  HTTPClient http;
  http.begin("https://silentcanary.com/checkin/YOUR_TOKEN");
  http.addHeader("Content-Type", "application/json");
  
  String message = "Temp: " + String(temperature) + "°C, Humidity: " + String(humidity) + "%";
  String payload = "{\"message\":\"" + message + "\"}";
  
  int httpResponseCode = http.POST(payload);
  
  if (httpResponseCode > 0) {
    Serial.println("Check-in successful");
  } else {
    Serial.println("Check-in failed");
  }
  
  http.end();
}

void loop() {
  sendSensorData();
  delay(600000); // 10 minutes
}

Different ways to send messages:

1. Simple GET request with message:

curl "https://silentcanary.com/checkin/YOUR_TOKEN?message=Task completed successfully"

2. POST with form data:

curl -X POST https://silentcanary.com/checkin/YOUR_TOKEN \
     -d "message=Processed 1,234 records in 5.2 seconds"

3. POST with JSON:

curl -X POST https://silentcanary.com/checkin/YOUR_TOKEN \
     -H "Content-Type: application/json" \
     -d '{"message": "System status: All services operational"}'

4. From JavaScript/Node.js:

fetch('https://silentcanary.com/checkin/YOUR_TOKEN', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    message: `Processed ${recordCount} records, ${errorCount} errors`
  })
});