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/fetchers/parseable.py

@@ -0,0 +1,64 @@
+"""Parseable log fetcher implementation."""
+
+import datetime
+import logging
+from time import time
+import requests
+from typing import Dict, Any, List
+
+from .base import LogFetcher
+
+logger = logging.getLogger("log-alert")
+
+
+class ParseableLogFetcher(LogFetcher):
+    """Concrete implementation for fetching logs from Parseable."""
+
+    def __init__(self, config: Dict[str, Any]):
+        self.url = config["url"]
+        self.dataset = config["dataset"]
+        self.user = config.get("user")
+        self.password = config.get("password")
+        self.last_fetched_time = int(time())  # Initialize with current time
+
+    def fetch_logs(self, filters: Dict[str, Any]) -> List[Dict[str, Any]]:
+        """Fetch logs from Parseable without time range."""
+        old_time = self.last_fetched_time
+        self.last_fetched_time = int(time())
+        return self.fetch_logs_time_range(filters, old_time, self.last_fetched_time)
+
+    def fetch_logs_time_range(self, filters: Dict[str, Any], start_time: int, end_time: int) -> List[Dict[str, Any]]:
+        """Fetch logs from Parseable within the specified time range."""
+        query = 'SELECT * FROM \''
+        query += f'{self.dataset}\' WHERE '
+        labelNum = 0
+        for label in filters.get("labels", {}):
+            if labelNum > 0:
+                query += ' AND '
+            query += f'{label}=\'{filters["labels"][label]}\''
+            labelNum += 1
+        if "text" in filters:
+            if labelNum > 0:
+                query += ' AND '
+            query += f'log LIKE \'%{filters["text"]}%\''
+        logger.debug(f"Executing Parseable query: {query}")
+        payload = {
+            "query": query,
+            "startTime": datetime.datetime.fromtimestamp(start_time).strftime("%Y-%m-%dT%H:%M:%SZ"),
+            "endTime": datetime.datetime.fromtimestamp(end_time).strftime("%Y-%m-%dT%H:%M:%SZ")
+        }
+        try:
+            response = requests.post(f"{self.url}/api/v1/query", json=payload, auth=(self.user, self.password), headers = { "Content-Type": "application/json" })
+            response.raise_for_status()
+            data = response.json()
+            logs = []
+            for item in data:
+                logs.append({
+                    "timestamp": item.get("p_timestamp"),
+                    "log": item.get("log"),
+                    "labels": {k: v for k, v in item.items() if k not in ["p_timestamp", "log"]}
+                })
+            return logs
+        except requests.exceptions.RequestException as e:
+            logger.error(f"Error fetching logs from Parseable: {e}")
+            return []