feat: Refactor log-alert application into modular structure

- Introduced alerters package with base Alerter class and implementations for LogAlerter and GotifyAlerter.
- Created fetchers package with abstract LogFetcher class and implementations for FileLogFetcher, LokiLogFetcher, and ParseableLogFetcher.
- Added filters package with base Filter class and implementations for RegexpFilter and GeolocationFilter.
- Implemented rules package with base AlertRule class and SimpleAlertRule for alerting logic.
- Enhanced configuration handling with utilities for loading and validating JSON configuration.
- Updated logging setup for better logging management.
- Modified main application logic to utilize the new modular structure, improving maintainability and readability.
- Updated config.json and config.schema.json to reflect changes in alerting and fetching configurations.
- Added python-dateutil to requirements for date parsing functionality.

log-alert/alerters/gotify.py

@@ -0,0 +1,30 @@
+"""Gotify alerter implementation."""
+
+import logging
+import requests
+from typing import Dict, Any
+
+from .base import Alerter
+
+logger = logging.getLogger("log-alert")
+
+
+class GotifyAlerter(Alerter):
+    """Concrete implementation for Gotify alert manager."""
+
+    def __init__(self, config: Dict[str, Any]):
+        self.url = config["url"]
+        self.token = config.get("token")
+
+    def send_alert(self, title: str, message: str) -> None:
+        """Send an alert to Gotify."""
+        payload = {
+            "title": title,
+            "message": message,
+            "priority": 5
+        }
+        try:
+            response = requests.post(f"{self.url}?token={self.token}", json=payload)
+            response.raise_for_status()
+        except requests.exceptions.RequestException as e:
+            logger.error(f"Error sending alert to Gotify: {e}")