Add JSON, syslog, and Apache parsers

loglens/parsers/syslog_parser.py

@@ -1,92 +1,212 @@
+"""Syslog parser for RFC 3164 and RFC 5424 formats."""
+
 import re
 from datetime import datetime
-from typing import Optional
+from typing import Any, Optional
 
-from loglens.parsers.base import BaseParser, LogFormat, ParsedEntry
+from dateutil import parser as date_parser
+
+from loglens.parsers.base import LogParser, ParsedLogEntry
 
 
-class SyslogParser(BaseParser):
-    """Parser for syslog formats."""
+class SyslogParser(LogParser):
+    """Parser for syslog format (RFC 3164 and RFC 5424)."""
 
-    RFC5424_PATTERN = re.compile(
-        r'^<(?P<prival>[0-9]+)>(?P<version>[0-9]) (?P<timestamp>[-:T\.0-9Z+]+) (?P<hostname>[^\s]+) (?P<appname>[^\s]+) (?P<procid>[^\s]+) (?P<msgid>[^\s]+) (?P<msg>.*)$'
+    format_name = "syslog"
+
+    SYSLOG_RFC3164_PATTERN = re.compile(
+        r"^(?P<month>[A-Z][a-z]{2})\s+(?P<day>\d{1,2})\s+(?P<hour>\d{2}):(?P<minute>\d{2}):(?P<second>\d{2})\s+(?P<hostname>[\w.-]+)\s+(?P<process>[\w\[\]]+):\s*(?P<message>.*)$"
     )
 
-    RFC3164_PATTERN = re.compile(
-        r'^(?P<timestamp>[A-Z][a-z]{2}\s+[0-9]{1,2}\s+[0-9]{2}:[0-9]{2}:[0-9]{2}) (?P<hostname>[^\s]+) (?P<appname>[^\s]+)(?:\[(?P<procid>[0-9]+)\])?: (?P<msg>.*)$'
+    SYSLOG_RFC5424_PATTERN = re.compile(
+        r"^(?P<pri><\d+>)?(?P<version>\d+)\s+(?P<timestamp>\S+)\s+(?P<hostname>\S+)\s+(?P<process>\S+)\s+(?P<pid>\S+)\s+(?P<msgid>\S+)?\s*(?P<struct_data>-)\s*(?P<message>.*)$"
     )
 
-    BSD_PATTERN = re.compile(
-        r'^(?P<timestamp>[A-Z][a-z]{2}\s+[0-9]{1,2}\s+[0-9]{2}:[0-9]{2}:[0-9]{2}) (?P<hostname>[^\s]+) (?P<appname>[^\s]+): (?P<msg>.*)$'
-    )
-
-    def get_format(self) -> LogFormat:
-        return LogFormat.SYSLOG
-
-    def parse(self, line: str) -> Optional[ParsedEntry]:
-        match = self.RFC5424_PATTERN.match(line)
-        if not match:
-            match = self.RFC3164_PATTERN.match(line)
-        if not match:
-            match = self.BSD_PATTERN.match(line)
-
-        if not match:
-            return None
-
-        timestamp = self._parse_timestamp(match.group("timestamp"), match.group("version") if "version" in match.groupdict() else None)
-
-        prival = match.group("prival") if "prival" in match.groupdict() else None
-        level = self._extract_severity(prival) if prival else None
-
-        return ParsedEntry(
-            raw_line=line,
-            format=self.get_format(),
-            timestamp=timestamp,
-            level=level,
-            message=match.group("msg"),
-            metadata={
-                "hostname": match.group("hostname"),
-                "appname": match.group("appname"),
-                "procid": match.group("procid") if "procid" in match.groupdict() else None,
-            },
-        )
-
-    def _parse_timestamp(self, timestamp_str: str, version: Optional[str] = None) -> Optional[str]:
-        if version == "1":
-            try:
-                dt = datetime.strptime(timestamp_str, "%Y-%m-%dT%H:%M:%S.%f%z")
-                return dt.isoformat()
-            except ValueError:
-                pass
-            try:
-                dt = datetime.strptime(timestamp_str, "%Y-%m-%dT%H:%M:%S%z")
-                return dt.isoformat()
-            except ValueError:
-                pass
-
-        for fmt in ["%b %d %H:%M:%S", "%b %d %H:%M:%S%z", "%Y-%m-%d %H:%M:%S"]:
-            try:
-                dt = datetime.strptime(timestamp_str, fmt)
-                return dt.isoformat()
-            except ValueError:
-                continue
-
-        return timestamp_str
-
-    def _extract_severity(self, prival: str) -> Optional[str]:
-        try:
-            code = int(prival)
-            severity = (code & 0x07)
-            severity_map = {
-                0: "critical",
-                1: "error",
-                2: "warning",
-                3: "info",
-                4: "debug",
-                5: "debug",
-                6: "debug",
+    PRIORITY_MAP = {
+        0: "emergency",
+        1: "alert",
+        2: "critical",
+        3: "error",
+        4: "warning",
+        5: "notice",
+        6: "info",
         7: "debug",
     }
-            return severity_map.get(severity)
-        except (ValueError, TypeError):
+
+    FACILITY_MAP = {
+        0: "kernel",
+        1: "user",
+        2: "mail",
+        3: "daemon",
+        4: "auth",
+        5: "syslog",
+        6: "lpr",
+        7: "news",
+        8: "uucp",
+        9: "clock",
+        10: "authpriv",
+        11: "ftp",
+        12: "ntp",
+        13: "logaudit",
+        14: "logalert",
+        15: "cron",
+        16: "local0",
+        17: "local1",
+        18: "local2",
+        19: "local3",
+        20: "local4",
+        21: "local5",
+        22: "local6",
+        23: "local7",
+    }
+
+    def __init__(self):
+        self.month_map = {
+            "Jan": 1,
+            "Feb": 2,
+            "Mar": 3,
+            "Apr": 4,
+            "May": 5,
+            "Jun": 6,
+            "Jul": 7,
+            "Aug": 8,
+            "Sep": 9,
+            "Oct": 10,
+            "Nov": 11,
+            "Dec": 12,
+        }
+
+    def can_parse(self, line: str) -> bool:
+        """Check if line matches syslog format."""
+        line = line.strip()
+        if not line:
+            return False
+
+        if line.startswith("<") and ">" in line:
+            parts = line.split(">", 1)
+            if parts[0][1:].isdigit():
+                return True
+
+        match = self.SYSLOG_RFC3164_PATTERN.match(line)
+        if match:
+            month = match.group("month")
+            if month in self.month_map:
+                return True
+
+        return False
+
+    def parse(self, line: str, line_number: int = 0) -> Optional[ParsedLogEntry]:
+        """Parse a syslog line."""
+        line = line.strip()
+        if not line:
+            return None
+
+        entry = ParsedLogEntry(raw_line=line, line_number=line_number)
+
+        if line.startswith("<"):
+            parsed = self._parse_rfc5424(line)
+        else:
+            parsed = self._parse_rfc3164(line)
+
+        if parsed:
+            entry.timestamp = parsed.get("timestamp")
+            entry.host = parsed.get("hostname")
+            entry.level = parsed.get("level")
+            entry.message = parsed.get("message", "")
+            entry.facility = parsed.get("facility")
+            entry.logger = parsed.get("process")
+
+        return entry
+
+    def _parse_rfc3164(self, line: str) -> Optional[dict[str, Any]]:
+        """Parse RFC 3164 syslog format."""
+        match = self.SYSLOG_RFC3164_PATTERN.match(line)
+        if not match:
+            return None
+
+        month = match.group("month")
+        day = int(match.group("day"))
+        hour = int(match.group("hour"))
+        minute = int(match.group("minute"))
+        second = int(match.group("second"))
+        hostname = match.group("hostname")
+        process = match.group("process")
+        message = match.group("message")
+
+        current_year = datetime.now().year
+        timestamp = datetime(current_year, self.month_map[month], day, hour, minute, second)
+
+        level = self._infer_level(message)
+
+        return {
+            "timestamp": timestamp,
+            "hostname": hostname,
+            "process": process,
+            "message": message,
+            "level": level,
+        }
+
+    def _parse_rfc5424(self, line: str) -> Optional[dict[str, Any]]:
+        """Parse RFC 5424 syslog format."""
+        match = self.SYSLOG_RFC5424_PATTERN.match(line)
+        if not match:
+            return None
+
+        raw_pri = match.group("pri")
+        _ = match.group("version")
+        timestamp_str = match.group("timestamp")
+        hostname = match.group("hostname")
+        process = match.group("process")
+        pid = match.group("pid")
+        _ = match.group("msgid")
+        _ = match.group("struct_data")
+        message = match.group("message")
+
+        try:
+            timestamp = date_parser.isoparse(timestamp_str)
+        except ValueError:
+            timestamp = datetime.now()
+
+        priority = None
+        facility = None
+        if raw_pri:
+            pri_num = int(raw_pri[1:-1])
+            priority = pri_num & 0x07
+            facility_num = pri_num >> 3
+            facility = self.FACILITY_MAP.get(facility_num)
+            level = self.PRIORITY_MAP.get(priority)
+
+        if not level:
+            level = self._infer_level(message)
+
+        return {
+            "timestamp": timestamp,
+            "hostname": hostname,
+            "process": f"{process}[{pid}]" if pid else process,
+            "message": message,
+            "level": level,
+            "facility": facility,
+        }
+
+    def _infer_level(self, message: str) -> Optional[str]:
+        """Infer log level from message content."""
+        message_lower = message.lower()
+
+        if any(kw in message_lower for kw in ["emerg", "panic", "critical system"]):
+            return "emergency"
+        elif any(kw in message_lower for kw in ["alert", "immediate action"]):
+            return "alert"
+        elif any(kw in message_lower for kw in ["critical", "fatal", "segfault"]):
+            return "critical"
+        elif any(kw in message_lower for kw in ["error", "exception", "failed", "failure"]):
+            return "error"
+        elif any(kw in message_lower for kw in ["warning", "warn", "deprecation"]):
+            return "warning"
+        elif any(kw in message_lower for kw in ["notice"]):
+            return "notice"
+        elif any(kw in message_lower for kw in ["info", "information"]):
+            return "info"
+        elif any(kw in message_lower for kw in ["debug", "trace"]):
+            return "debug"
+
         return None