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
27 import traceback as _traceback
29 import logging as _logging
30 if _sys.version_info >= (3,3):
31 from collections import ChainMap as _ChainMap
32 from syslog import (LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR,
33 LOG_WARNING, LOG_NOTICE, LOG_INFO, LOG_DEBUG)
34 from ._journal import __version__, sendv, stream_fd
35 from ._reader import (_Reader, NOP, APPEND, INVALIDATE,
36 LOCAL_ONLY, RUNTIME_ONLY,
37 SYSTEM, SYSTEM_ONLY, CURRENT_USER,
39 from . import id128 as _id128
41 if _sys.version_info >= (3,):
42 from ._reader import Monotonic
46 def _convert_monotonic(m):
47 return Monotonic((_datetime.timedelta(microseconds=m[0]),
48 _uuid.UUID(bytes=m[1])))
50 def _convert_source_monotonic(s):
51 return _datetime.timedelta(microseconds=int(s))
53 def _convert_realtime(t):
54 return _datetime.datetime.fromtimestamp(t / 1000000)
56 def _convert_timestamp(s):
57 return _datetime.datetime.fromtimestamp(int(s) / 1000000)
59 def _convert_trivial(x):
62 if _sys.version_info >= (3,):
64 return _uuid.UUID(s.decode())
66 _convert_uuid = _uuid.UUID
68 DEFAULT_CONVERTERS = {
69 'MESSAGE_ID': _convert_uuid,
70 '_MACHINE_ID': _convert_uuid,
71 '_BOOT_ID': _convert_uuid,
75 'USERSPACE_USEC': int,
81 'SYSLOG_FACILITY': int,
83 '_AUDIT_SESSION': int,
84 '_AUDIT_LOGINUID': int,
85 '_SYSTEMD_SESSION': int,
86 '_SYSTEMD_OWNER_UID': int,
90 '_SOURCE_REALTIME_TIMESTAMP': _convert_timestamp,
91 '__REALTIME_TIMESTAMP': _convert_realtime,
92 '_SOURCE_MONOTONIC_TIMESTAMP': _convert_source_monotonic,
93 '__MONOTONIC_TIMESTAMP': _convert_monotonic,
94 '__CURSOR': _convert_trivial,
99 'COREDUMP_SESSION': int,
100 'COREDUMP_SIGNAL': int,
101 'COREDUMP_TIMESTAMP': _convert_timestamp,
104 _IDENT_LETTER = set('ABCDEFGHIJKLMNOPQRTSUVWXYZ_')
106 def _valid_field_name(s):
107 return not (set(s) - _IDENT_LETTER)
109 class Reader(_Reader):
110 """Reader allows the access and filtering of systemd journal
111 entries. Note that in order to access the system journal, a
112 non-root user must be in the `systemd-journal` group.
114 Example usage to print out all informational or higher level
115 messages for systemd-udevd for this boot:
117 >>> j = journal.Reader()
119 >>> j.log_level(journal.LOG_INFO)
120 >>> j.add_match(_SYSTEMD_UNIT="systemd-udevd.service")
122 ... print(entry['MESSAGE'])
124 See systemd.journal-fields(7) for more info on typical fields
125 found in the journal.
127 def __init__(self, flags=0, path=None, files=None, converters=None):
128 """Create an instance of Reader, which allows filtering and
129 return of journal entries.
131 Argument `flags` sets open flags of the journal, which can be one
132 of, or ORed combination of constants: LOCAL_ONLY (default) opens
133 journal on local machine only; RUNTIME_ONLY opens only
134 volatile journal files; and SYSTEM_ONLY opens only
135 journal files of system services and the kernel.
137 Argument `path` is the directory of journal files. Note that
138 `flags` and `path` are exclusive.
140 Argument `converters` is a dictionary which updates the
141 DEFAULT_CONVERTERS to convert journal field values. Field
142 names are used as keys into this dictionary. The values must
143 be single argument functions, which take a `bytes` object and
144 return a converted value. When there's no entry for a field
145 name, then the default UTF-8 decoding will be attempted. If
146 the conversion fails with a ValueError, unconverted bytes
147 object will be returned. (Note that ValueEror is a superclass
148 of UnicodeDecodeError).
150 Reader implements the context manager protocol: the journal
151 will be closed when exiting the block.
153 super(Reader, self).__init__(flags, path, files)
154 if _sys.version_info >= (3,3):
155 self.converters = _ChainMap()
156 if converters is not None:
157 self.converters.maps.append(converters)
158 self.converters.maps.append(DEFAULT_CONVERTERS)
160 self.converters = DEFAULT_CONVERTERS.copy()
161 if converters is not None:
162 self.converters.update(converters)
164 def _convert_field(self, key, value):
165 """Convert value using self.converters[key]
167 If `key` is not present in self.converters, a standard unicode
168 decoding will be attempted. If the conversion (either
169 key-specific or the default one) fails with a ValueError, the
170 original bytes object will be returned.
172 convert = self.converters.get(key, bytes.decode)
174 return convert(value)
176 # Leave in default bytes
179 def _convert_entry(self, entry):
180 """Convert entire journal entry utilising _covert_field"""
182 for key, value in entry.items():
183 if isinstance(value, list):
184 result[key] = [self._convert_field(key, val) for val in value]
186 result[key] = self._convert_field(key, value)
190 """Part of iterator protocol.
196 """Part of iterator protocol.
197 Returns self.get_next() or raises StopIteration.
199 ans = self.get_next()
203 raise StopIteration()
205 if _sys.version_info < (3,):
208 def add_match(self, *args, **kwargs):
209 """Add one or more matches to the filter journal log entries.
210 All matches of different field are combined in a logical AND,
211 and matches of the same field are automatically combined in a
213 Matches can be passed as strings of form "FIELD=value", or
214 keyword arguments FIELD="value".
217 args.extend(_make_line(key, val) for key, val in kwargs.items())
219 super(Reader, self).add_match(arg)
221 def get_next(self, skip=1):
222 """Return the next log entry as a mapping type, currently
223 a standard dictionary of fields.
225 Optional skip value will return the `skip`\-th log entry.
227 Entries will be processed with converters specified during
230 if super(Reader, self)._next(skip):
231 entry = super(Reader, self)._get_all()
233 entry['__REALTIME_TIMESTAMP'] = self._get_realtime()
234 entry['__MONOTONIC_TIMESTAMP'] = self._get_monotonic()
235 entry['__CURSOR'] = self._get_cursor()
236 return self._convert_entry(entry)
239 def get_previous(self, skip=1):
240 """Return the previous log entry as a mapping type,
241 currently a standard dictionary of fields.
243 Optional skip value will return the -`skip`\-th log entry.
245 Entries will be processed with converters specified during
248 Equivalent to get_next(-skip).
250 return self.get_next(-skip)
252 def query_unique(self, field):
253 """Return unique values appearing in the journal for given `field`.
255 Note this does not respect any journal matches.
257 Entries will be processed with converters specified during
260 return set(self._convert_field(field, value)
261 for value in super(Reader, self).query_unique(field))
263 def wait(self, timeout=None):
264 """Wait for a change in the journal. `timeout` is the maximum
265 time in seconds to wait, or None, to wait forever.
267 Returns one of NOP (no change), APPEND (new entries have been
268 added to the end of the journal), or INVALIDATE (journal files
269 have been added or removed).
271 us = -1 if timeout is None else int(timeout * 1000000)
272 return super(Reader, self).wait(us)
274 def seek_realtime(self, realtime):
275 """Seek to a matching journal entry nearest to `realtime` time.
277 Argument `realtime` must be either an integer unix timestamp
278 or datetime.datetime instance.
280 if isinstance(realtime, _datetime.datetime):
281 realtime = float(realtime.strftime("%s.%f")) * 1000000
282 return super(Reader, self).seek_realtime(int(realtime))
284 def seek_monotonic(self, monotonic, bootid=None):
285 """Seek to a matching journal entry nearest to `monotonic` time.
287 Argument `monotonic` is a timestamp from boot in either
288 seconds or a datetime.timedelta instance. Argument `bootid`
289 is a string or UUID representing which boot the monotonic time
290 is reference to. Defaults to current bootid.
292 if isinstance(monotonic, _datetime.timedelta):
293 monotonic = monotonic.totalseconds()
294 monotonic = int(monotonic * 1000000)
295 if isinstance(bootid, _uuid.UUID):
296 bootid = bootid.get_hex()
297 return super(Reader, self).seek_monotonic(monotonic, bootid)
299 def log_level(self, level):
300 """Set maximum log `level` by setting matches for PRIORITY.
303 for i in range(level+1):
304 self.add_match(PRIORITY="%d" % i)
306 raise ValueError("Log level must be 0 <= level <= 7")
308 def messageid_match(self, messageid):
309 """Add match for log entries with specified `messageid`.
311 `messageid` can be string of hexadicimal digits or a UUID
312 instance. Standard message IDs can be found in systemd.id128.
314 Equivalent to add_match(MESSAGE_ID=`messageid`).
316 if isinstance(messageid, _uuid.UUID):
317 messageid = messageid.get_hex()
318 self.add_match(MESSAGE_ID=messageid)
320 def this_boot(self, bootid=None):
321 """Add match for _BOOT_ID equal to current boot ID or the specified boot ID.
323 If specified, bootid should be either a UUID or a 32 digit hex number.
325 Equivalent to add_match(_BOOT_ID='bootid').
328 bootid = _id128.get_boot().hex
330 bootid = getattr(bootid, 'hex', bootid)
331 self.add_match(_BOOT_ID=bootid)
333 def this_machine(self, machineid=None):
334 """Add match for _MACHINE_ID equal to the ID of this machine.
336 If specified, machineid should be either a UUID or a 32 digit hex number.
338 Equivalent to add_match(_MACHINE_ID='machineid').
340 if machineid is None:
341 machineid = _id128.get_machine().hex
343 machineid = getattr(machineid, 'hex', machineid)
344 self.add_match(_MACHINE_ID=machineid)
347 def get_catalog(mid):
348 if isinstance(mid, _uuid.UUID):
350 return _get_catalog(mid)
352 def _make_line(field, value):
353 if isinstance(value, bytes):
354 return field.encode('utf-8') + b'=' + value
355 elif isinstance(value, int):
356 return field + '=' + str(value)
358 return field + '=' + value
360 def send(MESSAGE, MESSAGE_ID=None,
361 CODE_FILE=None, CODE_LINE=None, CODE_FUNC=None,
363 r"""Send a message to the journal.
365 >>> journal.send('Hello world')
366 >>> journal.send('Hello, again, world', FIELD2='Greetings!')
367 >>> journal.send('Binary message', BINARY=b'\xde\xad\xbe\xef')
369 Value of the MESSAGE argument will be used for the MESSAGE=
370 field. MESSAGE must be a string and will be sent as UTF-8 to
373 MESSAGE_ID can be given to uniquely identify the type of
374 message. It must be a string or a uuid.UUID object.
376 CODE_LINE, CODE_FILE, and CODE_FUNC can be specified to
377 identify the caller. Unless at least on of the three is given,
378 values are extracted from the stack frame of the caller of
379 send(). CODE_FILE and CODE_FUNC must be strings, CODE_LINE
382 Additional fields for the journal entry can only be specified
383 as keyword arguments. The payload can be either a string or
384 bytes. A string will be sent as UTF-8, and bytes will be sent
385 as-is to the journal.
387 Other useful fields include PRIORITY, SYSLOG_FACILITY,
388 SYSLOG_IDENTIFIER, SYSLOG_PID.
391 args = ['MESSAGE=' + MESSAGE]
393 if MESSAGE_ID is not None:
394 id = getattr(MESSAGE_ID, 'hex', MESSAGE_ID)
395 args.append('MESSAGE_ID=' + id)
397 if CODE_LINE == CODE_FILE == CODE_FUNC == None:
398 CODE_FILE, CODE_LINE, CODE_FUNC = \
399 _traceback.extract_stack(limit=2)[0][:3]
400 if CODE_FILE is not None:
401 args.append('CODE_FILE=' + CODE_FILE)
402 if CODE_LINE is not None:
403 args.append('CODE_LINE={:d}'.format(CODE_LINE))
404 if CODE_FUNC is not None:
405 args.append('CODE_FUNC=' + CODE_FUNC)
407 args.extend(_make_line(key, val) for key, val in kwargs.items())
410 def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
411 r"""Return a file object wrapping a stream to journal.
413 Log messages written to this file as simple newline sepearted
414 text strings are written to the journal.
416 The file will be line buffered, so messages are actually sent
417 after a newline character is written.
419 >>> stream = journal.stream('myapp')
421 <open file '<fdopen>', mode 'w' at 0x...>
422 >>> stream.write('message...\n')
424 will produce the following message in the journal::
427 SYSLOG_IDENTIFIER=myapp
430 Using the interface with print might be more convinient:
432 >>> from __future__ import print_function
433 >>> print('message...', file=stream)
435 priority is the syslog priority, one of `LOG_EMERG`,
436 `LOG_ALERT`, `LOG_CRIT`, `LOG_ERR`, `LOG_WARNING`,
437 `LOG_NOTICE`, `LOG_INFO`, `LOG_DEBUG`.
439 level_prefix is a boolean. If true, kernel-style log priority
440 level prefixes (such as '<1>') are interpreted. See
441 sd-daemon(3) for more information.
444 fd = stream_fd(identifier, priority, level_prefix)
445 return _os.fdopen(fd, 'w', 1)
447 class JournalHandler(_logging.Handler):
448 """Journal handler class for the Python logging framework.
450 Please see the Python logging module documentation for an
451 overview: http://docs.python.org/library/logging.html.
453 To create a custom logger whose messages go only to journal:
455 >>> log = logging.getLogger('custom_logger_name')
456 >>> log.propagate = False
457 >>> log.addHandler(journal.JournalHandler())
458 >>> log.warn("Some message: %s", detail)
460 Note that by default, message levels `INFO` and `DEBUG` are
461 ignored by the logging framework. To enable those log levels:
463 >>> log.setLevel(logging.DEBUG)
465 To redirect all logging messages to journal regardless of where
466 they come from, attach it to the root logger:
468 >>> logging.root.addHandler(journal.JournalHandler())
470 For more complex configurations when using `dictConfig` or
471 `fileConfig`, specify `systemd.journal.JournalHandler` as the
472 handler class. Only standard handler configuration options
473 are supported: `level`, `formatter`, `filters`.
475 To attach journal MESSAGE_ID, an extra field is supported:
478 >>> mid = uuid.UUID('0123456789ABCDEF0123456789ABCDEF')
479 >>> log.warn("Message with ID", extra={'MESSAGE_ID': mid})
481 Fields to be attached to all messages sent through this
482 handler can be specified as keyword arguments. This probably
483 makes sense only for SYSLOG_IDENTIFIER and similar fields
484 which are constant for the whole program:
486 >>> journal.JournalHandler(SYSLOG_IDENTIFIER='my-cool-app')
488 The following journal fields will be sent:
489 `MESSAGE`, `PRIORITY`, `THREAD_NAME`, `CODE_FILE`, `CODE_LINE`,
490 `CODE_FUNC`, `LOGGER` (name as supplied to getLogger call),
491 `MESSAGE_ID` (optional, see above), `SYSLOG_IDENTIFIER` (defaults
495 def __init__(self, level=_logging.NOTSET, **kwargs):
496 super(JournalHandler, self).__init__(level)
499 if not _valid_field_name(name):
500 raise ValueError('Invalid field name: ' + name)
501 if 'SYSLOG_IDENTIFIER' not in kwargs:
502 kwargs['SYSLOG_IDENTIFIER'] = _sys.argv[0]
505 def emit(self, record):
506 """Write record as journal event.
508 MESSAGE is taken from the message provided by the
509 user, and PRIORITY, LOGGER, THREAD_NAME,
510 CODE_{FILE,LINE,FUNC} fields are appended
511 automatically. In addition, record.MESSAGE_ID will be
515 msg = self.format(record)
516 pri = self.mapPriority(record.levelno)
517 mid = getattr(record, 'MESSAGE_ID', None)
520 PRIORITY=format(pri),
522 THREAD_NAME=record.threadName,
523 CODE_FILE=record.pathname,
524 CODE_LINE=record.lineno,
525 CODE_FUNC=record.funcName,
528 self.handleError(record)
531 def mapPriority(levelno):
532 """Map logging levels to journald priorities.
534 Since Python log level numbers are "sparse", we have
535 to map numbers in between the standard levels too.
537 if levelno <= _logging.DEBUG:
539 elif levelno <= _logging.INFO:
541 elif levelno <= _logging.WARNING:
543 elif levelno <= _logging.ERROR:
545 elif levelno <= _logging.CRITICAL: