Source code for evennia.utils.logger

"""
Logging facilities

These are thin wrappers on top of Twisted's logging facilities; logs
are all directed either to stdout (if Evennia is running in
interactive mode) or to $GAME_DIR/server/logs.

The log_file() function uses its own threading system to log to
arbitrary files in $GAME_DIR/server/logs.

Note: All logging functions have two aliases, log_type() and
log_typemsg(). This is for historical, back-compatible reasons.

"""

import os
import time
from datetime import datetime
from traceback import format_exc

from twisted import logger as twisted_logger
from twisted.internet.threads import deferToThread
from twisted.python import logfile
from twisted.python import util as twisted_util

log = twisted_logger.Logger()

_LOGDIR = None
_LOG_ROTATE_SIZE = None
_TIMEZONE = None
_CHANNEL_LOG_NUM_TAIL_LINES = None

_TIME_FORMAT = "%Y-%m-%d %H:%M:%S"


def _log(msg, logfunc, prefix="", **kwargs):
    try:
        msg = str(msg)
    except Exception as err:
        msg = str(err)
    if kwargs:
        logfunc(msg, **kwargs)
    else:
        try:
            for line in msg.splitlines():
                logfunc("{line}", prefix=prefix, line=line)
        except Exception as err:
            log.error("Log failure: {err}", err=err)


# log call functions (each has legacy aliases)


[docs]def log_info(msg, **kwargs): """ Logs any generic debugging/informative info that should appear in the log. Args: msg: (string) The message to be logged. **kwargs: If given, The `msg` is parsed as a format string with `{..}` formatting markers that should match the keywords. """ _log(msg, log.info, **kwargs)
info = log_info log_infomsg = log_info log_msg = log_info
[docs]def log_warn(msg, **kwargs): """ Logs warnings that aren't critical but should be noted. Args: msg (str): The message to be logged. **kwargs: If given, The `msg` is parsed as a format string with `{..}` formatting markers that should match the keywords. """ _log(msg, log.warn, **kwargs)
warn = log_warn warning = log_warn log_warnmsg = log_warn
[docs]def log_err(msg, **kwargs): """ Logs an error message to the server log. Args: msg (str): The message to be logged. **kwargs: If given, The `msg` is parsed as a format string with `{..}` formatting markers that should match the keywords. """ _log(msg, log.error, **kwargs)
error = log_err err = log_err log_errmsg = log_err
[docs]def log_trace(msg=None, **kwargs): """ Log a traceback to the log. This should be called from within an exception. Args: msg (str, optional): Adds an extra line with added info at the end of the traceback in the log. **kwargs: If given, The `msg` is parsed as a format string with `{..}` formatting markers that should match the keywords. """ tracestring = format_exc() if tracestring: _log(tracestring, log.error, prefix="!!", **kwargs) if msg: _log(msg, log.error, prefix="!!", **kwargs)
log_tracemsg = log_trace exception = log_trace critical = log_trace trace = log_trace
[docs]def log_dep(msg, **kwargs): """ Prints a deprecation message. Args: msg (str): The deprecation message to log. **kwargs: If given, The `msg` is parsed as a format string with `{..}` formatting markers that should match the keywords. """ _log(msg, log.warn, prefix="DP", **kwargs)
dep = log_dep deprecated = log_dep log_depmsg = log_dep
[docs]def log_sec(msg, **kwargs): """ Prints a security-related message. Args: msg (str): The security message to log. **kwargs: If given, The `msg` is parsed as a format string with `{..}` formatting markers that should match the keywords. """ _log(msg, log.info, prefix="SS", **kwargs)
sec = log_sec security = log_sec log_secmsg = log_sec
[docs]def log_server(msg, **kwargs): """ This is for the Portal to log captured Server stdout messages (it's usually only used during startup, before Server log is open) Args: msg (str): The message to be logged. **kwargs: If given, The `msg` is parsed as a format string with `{..}` formatting markers that should match the keywords. """ _log(msg, log.info, prefix="Server", **kwargs)
[docs]class GetLogObserver: """ Sets up how the system logs are formatted. """ component_prefix = "" event_levels = { twisted_logger.LogLevel.debug: "??", twisted_logger.LogLevel.info: "..", twisted_logger.LogLevel.warn: "WW", twisted_logger.LogLevel.error: "EE", twisted_logger.LogLevel.critical: "!!", }
[docs] def format_log_event(self, event): """ By assigning log_system here, we skip the spammy display of namespace/level in the default log output. [component_prefix] [date] [system/lvl] [msg] """ # setting log_system fills the [..] block after the time stamp prefix = event.get("prefix", "") if prefix: event["log_system"] = prefix else: lvl = event.get("log_level", twisted_logger.LogLevel.info) event["log_system"] = self.event_levels.get(lvl, "-") event["log_format"] = str(event.get("log_format", "")) component_prefix = self.component_prefix or "" log_msg = twisted_logger.formatEventAsClassicLogText( event, formatTime=lambda e: twisted_logger.formatTime(e, _TIME_FORMAT) ) return f"{component_prefix}{log_msg}"
def __call__(self, outfile): return twisted_logger.FileLogObserver(outfile, self.format_log_event)
# Called by server/portal on startup
[docs]class GetPortalLogObserver(GetLogObserver): component_prefix = "|Portal| "
[docs]class GetServerLogObserver(GetLogObserver): component_prefix = ""
# logging overrides
[docs]def timeformat(when=None): """ This helper function will format the current time in the same way as the twisted logger does, including time zone info. Only difference from official logger is that we only use two digits for the year and don't show timezone for GMT times. Args: when (int, optional): This is a time in POSIX seconds on the form given by time.time(). If not given, this function will use the current time. Returns: timestring (str): A formatted string of the given time. """ when = when if when else time.time() # time zone offset: UTC - the actual offset tz_offset = datetime.utcfromtimestamp(when) - datetime.fromtimestamp(when) tz_offset = tz_offset.days * 86400 + tz_offset.seconds # correct given time to utc when = datetime.utcfromtimestamp(when - tz_offset) if tz_offset == 0: tz = "" else: tz_hour = abs(int(tz_offset // 3600)) tz_mins = abs(int(tz_offset // 60 % 60)) tz_sign = "-" if tz_offset >= 0 else "+" tz = "%s%02d%s" % (tz_sign, tz_hour, (":%02d" % tz_mins if tz_mins else "")) return "%d-%02d-%02d %02d:%02d:%02d%s" % ( when.year - 2000, when.month, when.day, when.hour, when.minute, when.second, tz, )
[docs]class WeeklyLogFile(logfile.DailyLogFile): """ Log file that rotates once per week by default. Overrides key methods to change format. """
[docs] def __init__(self, name, directory, defaultMode=None, day_rotation=7, max_size=1000000): """ Args: name (str): Name of log file. directory (str): Directory holding the file. defaultMode (str): Permissions used to create file. Defaults to current permissions of this file if it exists. day_rotation (int): How often to rotate the file. max_size (int): Max size of log file before rotation (regardless of time). Defaults to 1M. """ self.day_rotation = day_rotation self.max_size = max_size self.size = 0 logfile.DailyLogFile.__init__(self, name, directory, defaultMode=defaultMode)
def _openFile(self): logfile.DailyLogFile._openFile(self) self.size = self._file.tell()
[docs] def shouldRotate(self): """Rotate when the date has changed since last write""" # all dates here are tuples (year, month, day) now = self.toDate() then = self.lastDate return ( now[0] > then[0] or now[1] > then[1] or now[2] > (then[2] + self.day_rotation) or self.size >= self.max_size )
[docs] def suffix(self, tupledate): """Return the suffix given a (year, month, day) tuple or unixtime. Format changed to have 03 for march instead of 3 etc (retaining unix file order) If we get duplicate suffixes in location (due to hitting size limit), we append __1, __2 etc. Examples: server.log.2020_01_29 server.log.2020_01_29__1 server.log.2020_01_29__2 """ suffix = "" copy_suffix = 0 while True: try: suffix = "_".join(["{:02d}".format(part) for part in tupledate]) except Exception: # try taking a float unixtime suffix = "_".join(["{:02d}".format(part) for part in self.toDate(tupledate)]) suffix += f"__{copy_suffix}" if copy_suffix else "" if os.path.exists(f"{self.path}.{suffix}"): # Append a higher copy_suffix to try to break the tie (starting from 2) copy_suffix += 1 else: break return suffix
[docs] def rotate(self): try: super().rotate() except Exception: log_trace(f"Could not rotate the log file {self.name}.")
[docs] def write(self, data): """ Write data to log file """ logfile.BaseLogFile.write(self, data) self.lastDate = max(self.lastDate, self.toDate()) self.size += len(data)
# Arbitrary file logger
[docs]class EvenniaLogFile(logfile.LogFile): """ A rotating logfile based off Twisted's LogFile. It overrides the LogFile's rotate method in order to append some of the last lines of the previous log to the start of the new log, in order to preserve a continuous chat history for channel log files. """ # we delay import of settings to keep logger module as free # from django as possible. global _CHANNEL_LOG_NUM_TAIL_LINES if _CHANNEL_LOG_NUM_TAIL_LINES is None: from django.conf import settings _CHANNEL_LOG_NUM_TAIL_LINES = settings.CHANNEL_LOG_NUM_TAIL_LINES num_lines_to_append = max(1, _CHANNEL_LOG_NUM_TAIL_LINES)
[docs] def rotate(self, num_lines_to_append=None): """ Rotates our log file and appends some number of lines from the previous log to the start of the new one. """ append_tail = ( num_lines_to_append if num_lines_to_append is not None else self.num_lines_to_append ) if not append_tail: logfile.LogFile.rotate(self) return lines = tail_log_file(self.path, 0, self.num_lines_to_append) super().rotate() for line in lines: self.write(line)
[docs] def seek(self, *args, **kwargs): """ Convenience method for accessing our _file attribute's seek method, which is used in tail_log_function. Args: *args: Same args as file.seek **kwargs: Same kwargs as file.seek """ return self._file.seek(*args, **kwargs)
[docs] def readlines(self, *args, **kwargs): """ Convenience method for accessing our _file attribute's readlines method, which is used in tail_log_function. Args: *args: same args as file.readlines **kwargs: same kwargs as file.readlines Returns: lines (list): lines from our _file attribute. """ lines = [] for line in self._file.readlines(*args, **kwargs): try: lines.append(line.decode("utf-8")) except UnicodeDecodeError: try: lines.append(str(line)) except Exception: lines.append("") return lines
_LOG_FILE_HANDLES = {} # holds open log handles _LOG_FILE_HANDLE_COUNTS = {} _LOG_FILE_HANDLE_RESET = 500 def _open_log_file(filename): """ Helper to open the log file (always in the log dir) and cache its handle. Will create a new file in the log dir if one didn't exist. To avoid keeping the filehandle open indefinitely we reset it every _LOG_FILE_HANDLE_RESET accesses. This may help resolve issues for very long uptimes and heavy log use. """ # we delay import of settings to keep logger module as free # from django as possible. global _LOG_FILE_HANDLES, _LOG_FILE_HANDLE_COUNTS, _LOGDIR, _LOG_ROTATE_SIZE if not _LOGDIR: from django.conf import settings _LOGDIR = settings.LOG_DIR _LOG_ROTATE_SIZE = max(1000, settings.CHANNEL_LOG_ROTATE_SIZE) filename = os.path.join(_LOGDIR, filename) if filename in _LOG_FILE_HANDLES: _LOG_FILE_HANDLE_COUNTS[filename] += 1 if _LOG_FILE_HANDLE_COUNTS[filename] > _LOG_FILE_HANDLE_RESET: # close/refresh handle _LOG_FILE_HANDLES[filename].close() del _LOG_FILE_HANDLES[filename] else: # return cached handle return _LOG_FILE_HANDLES[filename] try: filehandle = EvenniaLogFile.fromFullPath(filename, rotateLength=_LOG_ROTATE_SIZE) # filehandle = open(filename, "a+") # append mode + reading _LOG_FILE_HANDLES[filename] = filehandle _LOG_FILE_HANDLE_COUNTS[filename] = 0 return filehandle except IOError: log_trace() return None
[docs]def log_file(msg, filename="game.log"): """ Arbitrary file logger using threads. Args: msg (str): String to append to logfile. filename (str, optional): Defaults to 'game.log'. All logs will appear in the logs directory and log entries will start on new lines following datetime info. """ def callback(filehandle, msg): """Writing to file and flushing result""" msg = "\n%s [-] %s" % (timeformat(), msg.strip()) filehandle.write(msg) # since we don't close the handle, we need to flush # manually or log file won't be written to until the # write buffer is full. filehandle.flush() def errback(failure): """Catching errors to normal log""" log_trace() # save to server/logs/ directory filehandle = _open_log_file(filename) if filehandle: deferToThread(callback, filehandle, msg).addErrback(errback)
[docs]def log_file_exists(filename="game.log"): """ Determine if a log-file already exists. Args: filename (str): The filename (within the log-dir). Returns: bool: If the log file exists or not. """ global _LOGDIR if not _LOGDIR: from django.conf import settings _LOGDIR = settings.LOG_DIR filename = os.path.join(_LOGDIR, filename) return os.path.exists(filename)
[docs]def rotate_log_file(filename="game.log", num_lines_to_append=None): """ Force-rotate a log-file, without Args: filename (str): The log file, located in settings.LOG_DIR. num_lines_to_append (int, optional): Include N number of lines from previous file in new one. If `None`, use default. Set to 0 to include no lines. """ if log_file_exists(filename): file_handle = _open_log_file(filename) if file_handle: file_handle.rotate(num_lines_to_append=num_lines_to_append)
[docs]def delete_log_file(filename): """ Delete a log file Args: filename(str): The name of the log file, located in settings.LOG_DIR """ if log_file_exists(filename): global _LOGDIR if not _LOGDIR: from django.conf import settings _LOGDIR = settings.LOG_DIR filename = os.path.join(_LOGDIR, filename) os.remove(filename)
[docs]def tail_log_file(filename, offset, nlines, callback=None): """ Return the tail of the log file. Args: filename (str): The name of the log file, presumed to be in the Evennia log dir. offset (int): The line offset *from the end of the file* to start reading from. 0 means to start at the latest entry. nlines (int): How many lines to return, counting backwards from the offset. If file is shorter, will get all lines. callback (callable, optional): A function to manage the result of the asynchronous file access. This will get a list of lines. If unset, the tail will happen synchronously. Returns: lines (deferred or list): This will be a deferred if `callable` is given, otherwise it will be a list with The nline entries from the end of the file, or all if the file is shorter than nlines. """ def seek_file(filehandle, offset, nlines, callback): """step backwards in chunks and stop only when we have enough lines""" lines_found = [] buffer_size = 4098 block_count = -1 while len(lines_found) < (offset + nlines): try: # scan backwards in file, starting from the end filehandle.seek(block_count * buffer_size, os.SEEK_END) except IOError: # file too small for this seek, take what we've got filehandle.seek(0) lines_found = filehandle.readlines() break lines_found = filehandle.readlines() block_count -= 1 # return the right number of lines lines_found = lines_found[-nlines - offset : -offset if offset else None] if callback: callback(lines_found) return None else: return lines_found def errback(failure): """Catching errors to normal log""" log_trace() filehandle = _open_log_file(filename) if filehandle: if callback: return deferToThread(seek_file, filehandle, offset, nlines, callback).addErrback( errback ) else: return seek_file(filehandle, offset, nlines, callback) else: return None