1 # -*- Mode: python; coding:utf-8; indent-tabs-mode: nil -*- */
3 # This file is part of systemd.
5 # Copyright 2012 David Strauss <david@davidstrauss.net>
6 # Copyright 2012 Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
7 # Copyright 2012 Marti Raudsepp <marti@juffo.org>
9 # systemd is free software; you can redistribute it and/or modify it
10 # under the terms of the GNU Lesser General Public License as published by
11 # the Free Software Foundation; either version 2.1 of the License, or
12 # (at your option) any later version.
14 # systemd is distributed in the hope that it will be useful, but
15 # WITHOUT ANY WARRANTY; without even the implied warranty of
16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 # Lesser General Public License for more details.
19 # You should have received a copy of the GNU Lesser General Public License
20 # along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 from __future__ import division
25 import datetime as _datetime
26 import functools as _functools
28 import traceback as _traceback
30 import logging as _logging
31 if _sys.version_info >= (3,):
32 from collections import ChainMap as _ChainMap
33 from syslog import (LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR,
34 LOG_WARNING, LOG_NOTICE, LOG_INFO, LOG_DEBUG)
35 from ._journal import sendv, stream_fd
36 from ._reader import (_Reader, NOP, APPEND, INVALIDATE,
37 LOCAL_ONLY, RUNTIME_ONLY, SYSTEM_ONLY)
38 from . import id128 as _id128
40 if _sys.version_info >= (3,):
41 from ._reader import Monotonic
45 def _convert_monotonic(m):
46 return Monotonic((_datetime.timedelta(microseconds=m[0]),
47 _uuid.UUID(bytes=m[1])))
49 def _convert_source_monotonic(s):
50 return _datetime.timedelta(microseconds=int(s))
52 def _convert_realtime(t):
53 return _datetime.datetime.fromtimestamp(t / 1E6)
55 def _convert_timestamp(s):
56 return _datetime.datetime.fromtimestamp(int(s) / 1E6)
58 if _sys.version_info >= (3,):
60 return _uuid.UUID(s.decode())
62 _convert_uuid = _uuid.UUID
64 DEFAULT_CONVERTERS = {
65 'MESSAGE_ID': _convert_uuid,
66 '_MACHINE_ID': _convert_uuid,
67 '_BOOT_ID': _convert_uuid,
71 'USERSPACE_USEC': int,
77 'SYSLOG_FACILITY': int,
79 '_AUDIT_SESSION': int,
80 '_AUDIT_LOGINUID': int,
81 '_SYSTEMD_SESSION': int,
82 '_SYSTEMD_OWNER_UID': int,
86 '_SOURCE_REALTIME_TIMESTAMP': _convert_timestamp,
87 '__REALTIME_TIMESTAMP': _convert_realtime,
88 '_SOURCE_MONOTONIC_TIMESTAMP': _convert_source_monotonic,
89 '__MONOTONIC_TIMESTAMP': _convert_monotonic,
94 'COREDUMP_SESSION': int,
95 'COREDUMP_SIGNAL': int,
96 'COREDUMP_TIMESTAMP': _convert_timestamp,
99 class Reader(_Reader):
100 """Reader allows the access and filtering of systemd journal
101 entries. Note that in order to access the system journal, a
102 non-root user must be in the `adm` group.
104 Example usage to print out all informational or higher level
105 messages for systemd-udevd for this boot:
107 >>> j = journal.Reader()
109 >>> j.log_level(journal.LOG_INFO)
110 >>> j.add_match(_SYSTEMD_UNIT="systemd-udevd.service")
112 ... print(entry['MESSAGE'])
114 See systemd.journal-fields(7) for more info on typical fields
115 found in the journal.
117 def __init__(self, flags=LOCAL_ONLY, path=None, converters=None):
118 """Create an instance of Reader, which allows filtering and
119 return of journal entries.
121 Argument `flags` sets open flags of the journal, which can be one
122 of, or ORed combination of constants: LOCAL_ONLY (default) opens
123 journal on local machine only; RUNTIME_ONLY opens only
124 volatile journal files; and SYSTEM_ONLY opens only
125 journal files of system services and the kernel.
127 Argument `path` is the directory of journal files. Note that
128 currently flags are ignored when `path` is present as they are
129 currently not relevant.
131 Argument `converters` is a dictionary which updates the
132 DEFAULT_CONVERTERS to convert journal field values. Field
133 names are used as keys into this dictionary. The values must
134 be single argument functions, which take a `bytes` object and
135 return a converted value. When there's no entry for a field
136 name, then the default UTF-8 decoding will be attempted. If
137 the conversion fails with a ValueError, unconverted bytes
138 object will be returned. (Note that ValueEror is a superclass
139 of UnicodeDecodeError).
141 super(Reader, self).__init__(flags, path)
142 if _sys.version_info >= (3,3):
143 self.converters = _ChainMap()
144 if converters is not None:
145 self.converters.maps.append(converters)
146 self.converters.maps.append(DEFAULT_CONVERTERS)
148 self.converters = DEFAULT_CONVERTERS.copy()
149 if converters is not None:
150 self.converters.update(converters)
152 def _convert_field(self, key, value):
153 """Convert value using self.converters[key]
155 If `key` is not present in self.converters, a standard unicode
156 decoding will be attempted. If the conversion (either
157 key-specific or the default one) fails with a ValueError, the
158 original bytes object will be returned.
160 convert = self.converters.get(key, bytes.decode)
162 return convert(value)
164 # Leave in default bytes
167 def _convert_entry(self, entry):
168 """Convert entire journal entry utilising _covert_field"""
170 for key, value in entry.items():
171 if isinstance(value, list):
172 result[key] = [self._convert_field(key, val) for val in value]
174 result[key] = self._convert_field(key, value)
177 def add_match(self, *args, **kwargs):
178 """Add one or more matches to the filter journal log entries.
179 All matches of different field are combined in a logical AND,
180 and matches of the same field are automatically combined in a
182 Matches can be passed as strings of form "FIELD=value", or
183 keyword arguments FIELD="value".
186 args.extend(_make_line(key, val) for key, val in kwargs.items())
188 super(Reader, self).add_match(arg)
190 def get_next(self, skip=1):
191 """Return the next log entry as a dictionary of fields.
193 Optional skip value will return the `skip`\-th log entry.
195 Entries will be processed with converters specified during
198 return self._convert_entry(
199 super(Reader, self).get_next(skip))
201 def query_unique(self, field):
202 """Return unique values appearing in the journal for given `field`.
204 Note this does not respect any journal matches.
206 Entries will be processed with converters specified during
209 return set(self._convert_field(field, value)
210 for value in super(Reader, self).query_unique(field))
212 def seek_realtime(self, realtime):
213 """Seek to a matching journal entry nearest to `realtime` time.
215 Argument `realtime` must be either an integer unix timestamp
216 or datetime.datetime instance.
218 if isinstance(realtime, _datetime.datetime):
219 realtime = float(realtime.strftime("%s.%f"))
220 return super(Reader, self).seek_realtime(realtime)
222 def seek_monotonic(self, monotonic, bootid=None):
223 """Seek to a matching journal entry nearest to `monotonic` time.
225 Argument `monotonic` is a timestamp from boot in either
226 seconds or a datetime.timedelta instance. Argument `bootid`
227 is a string or UUID representing which boot the monotonic time
228 is reference to. Defaults to current bootid.
230 if isinstance(monotonic, _datetime.timedelta):
231 monotonic = monotonic.totalseconds()
232 if isinstance(bootid, _uuid.UUID):
233 bootid = bootid.get_hex()
234 return super(Reader, self).seek_monotonic(monotonic, bootid)
236 def log_level(self, level):
237 """Set maximum log `level` by setting matches for PRIORITY.
240 for i in range(level+1):
241 self.add_match(PRIORITY="%d" % i)
243 raise ValueError("Log level must be 0 <= level <= 7")
245 def messageid_match(self, messageid):
246 """Add match for log entries with specified `messageid`.
248 `messageid` can be string of hexadicimal digits or a UUID
249 instance. Standard message IDs can be found in systemd.id128.
251 Equivalent to add_match(MESSAGE_ID=`messageid`).
253 if isinstance(messageid, _uuid.UUID):
254 messageid = messageid.get_hex()
255 self.add_match(MESSAGE_ID=messageid)
257 def this_boot(self, bootid=None):
258 """Add match for _BOOT_ID equal to current boot ID or the specified boot ID.
260 If specified, bootid should be either a UUID or a 32 digit hex number.
262 Equivalent to add_match(_BOOT_ID='bootid').
265 bootid = _id128.get_boot().hex
267 bootid = getattr(bootid, 'hex', bootid)
268 self.add_match(_BOOT_ID=bootid)
270 def this_machine(self, machineid=None):
271 """Add match for _MACHINE_ID equal to the ID of this machine.
273 If specified, machineid should be either a UUID or a 32 digit hex number.
275 Equivalent to add_match(_MACHINE_ID='machineid').
277 if machineid is None:
278 machineid = _id128.get_machine().hex
280 machineid = getattr(machineid, 'hex', machineid)
281 self.add_match(_MACHINE_ID=machineid)
284 def _make_line(field, value):
285 if isinstance(value, bytes):
286 return field.encode('utf-8') + b'=' + value
288 return field + '=' + value
290 def send(MESSAGE, MESSAGE_ID=None,
291 CODE_FILE=None, CODE_LINE=None, CODE_FUNC=None,
293 r"""Send a message to the journal.
295 >>> journal.send('Hello world')
296 >>> journal.send('Hello, again, world', FIELD2='Greetings!')
297 >>> journal.send('Binary message', BINARY=b'\xde\xad\xbe\xef')
299 Value of the MESSAGE argument will be used for the MESSAGE=
300 field. MESSAGE must be a string and will be sent as UTF-8 to
303 MESSAGE_ID can be given to uniquely identify the type of
304 message. It must be a string or a uuid.UUID object.
306 CODE_LINE, CODE_FILE, and CODE_FUNC can be specified to
307 identify the caller. Unless at least on of the three is given,
308 values are extracted from the stack frame of the caller of
309 send(). CODE_FILE and CODE_FUNC must be strings, CODE_LINE
312 Additional fields for the journal entry can only be specified
313 as keyword arguments. The payload can be either a string or
314 bytes. A string will be sent as UTF-8, and bytes will be sent
315 as-is to the journal.
317 Other useful fields include PRIORITY, SYSLOG_FACILITY,
318 SYSLOG_IDENTIFIER, SYSLOG_PID.
321 args = ['MESSAGE=' + MESSAGE]
323 if MESSAGE_ID is not None:
324 id = getattr(MESSAGE_ID, 'hex', MESSAGE_ID)
325 args.append('MESSAGE_ID=' + id)
327 if CODE_LINE == CODE_FILE == CODE_FUNC == None:
328 CODE_FILE, CODE_LINE, CODE_FUNC = \
329 _traceback.extract_stack(limit=2)[0][:3]
330 if CODE_FILE is not None:
331 args.append('CODE_FILE=' + CODE_FILE)
332 if CODE_LINE is not None:
333 args.append('CODE_LINE={:d}'.format(CODE_LINE))
334 if CODE_FUNC is not None:
335 args.append('CODE_FUNC=' + CODE_FUNC)
337 args.extend(_make_line(key, val) for key, val in kwargs.items())
340 def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
341 r"""Return a file object wrapping a stream to journal.
343 Log messages written to this file as simple newline sepearted
344 text strings are written to the journal.
346 The file will be line buffered, so messages are actually sent
347 after a newline character is written.
349 >>> stream = journal.stream('myapp')
351 <open file '<fdopen>', mode 'w' at 0x...>
352 >>> stream.write('message...\n')
354 will produce the following message in the journal::
357 SYSLOG_IDENTIFIER=myapp
360 Using the interface with print might be more convinient:
362 >>> from __future__ import print_function
363 >>> print('message...', file=stream)
365 priority is the syslog priority, one of `LOG_EMERG`,
366 `LOG_ALERT`, `LOG_CRIT`, `LOG_ERR`, `LOG_WARNING`,
367 `LOG_NOTICE`, `LOG_INFO`, `LOG_DEBUG`.
369 level_prefix is a boolean. If true, kernel-style log priority
370 level prefixes (such as '<1>') are interpreted. See
371 sd-daemon(3) for more information.
374 fd = stream_fd(identifier, priority, level_prefix)
375 return _os.fdopen(fd, 'w', 1)
377 class JournalHandler(_logging.Handler):
378 """Journal handler class for the Python logging framework.
380 Please see the Python logging module documentation for an
381 overview: http://docs.python.org/library/logging.html.
383 To create a custom logger whose messages go only to journal:
385 >>> log = logging.getLogger('custom_logger_name')
386 >>> log.propagate = False
387 >>> log.addHandler(journal.JournalHandler())
388 >>> log.warn("Some message: %s", detail)
390 Note that by default, message levels `INFO` and `DEBUG` are
391 ignored by the logging framework. To enable those log levels:
393 >>> log.setLevel(logging.DEBUG)
395 To attach journal MESSAGE_ID, an extra field is supported:
398 >>> mid = uuid.UUID('0123456789ABCDEF0123456789ABCDEF')
399 >>> log.warn("Message with ID", extra={'MESSAGE_ID': mid})
401 To redirect all logging messages to journal regardless of where
402 they come from, attach it to the root logger:
404 >>> logging.root.addHandler(journal.JournalHandler())
406 For more complex configurations when using `dictConfig` or
407 `fileConfig`, specify `systemd.journal.JournalHandler` as the
408 handler class. Only standard handler configuration options
409 are supported: `level`, `formatter`, `filters`.
411 The following journal fields will be sent:
412 `MESSAGE`, `PRIORITY`, `THREAD_NAME`, `CODE_FILE`, `CODE_LINE`,
413 `CODE_FUNC`, `LOGGER` (name as supplied to getLogger call),
414 `MESSAGE_ID` (optional, see above).
417 def emit(self, record):
418 """Write record as journal event.
420 MESSAGE is taken from the message provided by the
421 user, and PRIORITY, LOGGER, THREAD_NAME,
422 CODE_{FILE,LINE,FUNC} fields are appended
423 automatically. In addition, record.MESSAGE_ID will be
427 msg = self.format(record)
428 pri = self.mapPriority(record.levelno)
429 mid = getattr(record, 'MESSAGE_ID', None)
432 PRIORITY=format(pri),
434 THREAD_NAME=record.threadName,
435 CODE_FILE=record.pathname,
436 CODE_LINE=record.lineno,
437 CODE_FUNC=record.funcName)
439 self.handleError(record)
442 def mapPriority(levelno):
443 """Map logging levels to journald priorities.
445 Since Python log level numbers are "sparse", we have
446 to map numbers in between the standard levels too.
448 if levelno <= _logging.DEBUG:
450 elif levelno <= _logging.INFO:
452 elif levelno <= _logging.WARNING:
454 elif levelno <= _logging.ERROR:
456 elif levelno <= _logging.CRITICAL: