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,):
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 sendv, stream_fd
35 from ._reader import (_Reader, NOP, APPEND, INVALIDATE,
36 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 / 1000000)
55 def _convert_timestamp(s):
56 return _datetime.datetime.fromtimestamp(int(s) / 1000000)
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 `systemd-journal` 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=0, 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 `flags` and `path` are exclusive.
130 Argument `converters` is a dictionary which updates the
131 DEFAULT_CONVERTERS to convert journal field values. Field
132 names are used as keys into this dictionary. The values must
133 be single argument functions, which take a `bytes` object and
134 return a converted value. When there's no entry for a field
135 name, then the default UTF-8 decoding will be attempted. If
136 the conversion fails with a ValueError, unconverted bytes
137 object will be returned. (Note that ValueEror is a superclass
138 of UnicodeDecodeError).
140 Reader implements the context manager protocol: the journal
141 will be closed when exiting the block.
143 super(Reader, self).__init__(flags, path)
144 if _sys.version_info >= (3,3):
145 self.converters = _ChainMap()
146 if converters is not None:
147 self.converters.maps.append(converters)
148 self.converters.maps.append(DEFAULT_CONVERTERS)
150 self.converters = DEFAULT_CONVERTERS.copy()
151 if converters is not None:
152 self.converters.update(converters)
154 def _convert_field(self, key, value):
155 """Convert value using self.converters[key]
157 If `key` is not present in self.converters, a standard unicode
158 decoding will be attempted. If the conversion (either
159 key-specific or the default one) fails with a ValueError, the
160 original bytes object will be returned.
162 convert = self.converters.get(key, bytes.decode)
164 return convert(value)
166 # Leave in default bytes
169 def _convert_entry(self, entry):
170 """Convert entire journal entry utilising _covert_field"""
172 for key, value in entry.items():
173 if isinstance(value, list):
174 result[key] = [self._convert_field(key, val) for val in value]
176 result[key] = self._convert_field(key, value)
180 """Part of iterator protocol.
185 if _sys.version_info >= (3,):
187 """Part of iterator protocol.
188 Returns self.get_next().
190 return self.get_next()
193 """Part of iterator protocol.
194 Returns self.get_next().
196 return self.get_next()
198 def add_match(self, *args, **kwargs):
199 """Add one or more matches to the filter journal log entries.
200 All matches of different field are combined in a logical AND,
201 and matches of the same field are automatically combined in a
203 Matches can be passed as strings of form "FIELD=value", or
204 keyword arguments FIELD="value".
207 args.extend(_make_line(key, val) for key, val in kwargs.items())
209 super(Reader, self).add_match(arg)
211 def get_next(self, skip=1):
212 """Return the next log entry as a mapping type, currently
213 a standard dictionary of fields.
215 Optional skip value will return the `skip`\-th log entry.
217 Entries will be processed with converters specified during
220 if super(Reader, self)._next(skip):
221 entry = super(Reader, self)._get_all()
223 entry['__REALTIME_TIMESTAMP'] = self._get_realtime()
224 entry['__MONOTONIC_TIMESTAMP'] = self._get_monotonic()
225 entry['__CURSOR'] = self._get_cursor()
226 return self._convert_entry(entry)
229 def get_previous(self, skip=1):
230 """Return the previous log entry as a mapping type,
231 currently a standard dictionary of fields.
233 Optional skip value will return the -`skip`\-th log entry.
235 Entries will be processed with converters specified during
238 Equivilent to get_next(-skip).
240 return self.get_next(-skip)
242 def query_unique(self, field):
243 """Return unique values appearing in the journal for given `field`.
245 Note this does not respect any journal matches.
247 Entries will be processed with converters specified during
250 return set(self._convert_field(field, value)
251 for value in super(Reader, self).query_unique(field))
253 def wait(self, timeout=None):
254 """Wait for a change in the journal. `timeout` is the maximum
255 time in seconds to wait, or None, to wait forever.
257 Returns one of NOP (no change), APPEND (new entries have been
258 added to the end of the journal), or INVALIDATE (journal files
259 have been added or removed).
261 us = -1 if timeout is None else int(timeout * 1000000)
262 return super(Reader, self).wait(us)
264 def seek_realtime(self, realtime):
265 """Seek to a matching journal entry nearest to `realtime` time.
267 Argument `realtime` must be either an integer unix timestamp
268 or datetime.datetime instance.
270 if isinstance(realtime, _datetime.datetime):
271 realtime = float(realtime.strftime("%s.%f")) * 1000000
272 return super(Reader, self).seek_realtime(int(realtime))
274 def seek_monotonic(self, monotonic, bootid=None):
275 """Seek to a matching journal entry nearest to `monotonic` time.
277 Argument `monotonic` is a timestamp from boot in either
278 seconds or a datetime.timedelta instance. Argument `bootid`
279 is a string or UUID representing which boot the monotonic time
280 is reference to. Defaults to current bootid.
282 if isinstance(monotonic, _datetime.timedelta):
283 monotonic = monotonic.totalseconds()
284 monotonic = int(monotonic * 1000000)
285 if isinstance(bootid, _uuid.UUID):
286 bootid = bootid.get_hex()
287 return super(Reader, self).seek_monotonic(monotonic, bootid)
289 def log_level(self, level):
290 """Set maximum log `level` by setting matches for PRIORITY.
293 for i in range(level+1):
294 self.add_match(PRIORITY="%d" % i)
296 raise ValueError("Log level must be 0 <= level <= 7")
298 def messageid_match(self, messageid):
299 """Add match for log entries with specified `messageid`.
301 `messageid` can be string of hexadicimal digits or a UUID
302 instance. Standard message IDs can be found in systemd.id128.
304 Equivalent to add_match(MESSAGE_ID=`messageid`).
306 if isinstance(messageid, _uuid.UUID):
307 messageid = messageid.get_hex()
308 self.add_match(MESSAGE_ID=messageid)
310 def this_boot(self, bootid=None):
311 """Add match for _BOOT_ID equal to current boot ID or the specified boot ID.
313 If specified, bootid should be either a UUID or a 32 digit hex number.
315 Equivalent to add_match(_BOOT_ID='bootid').
318 bootid = _id128.get_boot().hex
320 bootid = getattr(bootid, 'hex', bootid)
321 self.add_match(_BOOT_ID=bootid)
323 def this_machine(self, machineid=None):
324 """Add match for _MACHINE_ID equal to the ID of this machine.
326 If specified, machineid should be either a UUID or a 32 digit hex number.
328 Equivalent to add_match(_MACHINE_ID='machineid').
330 if machineid is None:
331 machineid = _id128.get_machine().hex
333 machineid = getattr(machineid, 'hex', machineid)
334 self.add_match(_MACHINE_ID=machineid)
337 def get_catalog(mid):
338 if isinstance(mid, _uuid.UUID):
340 return _get_catalog(mid)
342 def _make_line(field, value):
343 if isinstance(value, bytes):
344 return field.encode('utf-8') + b'=' + value
346 return field + '=' + value
348 def send(MESSAGE, MESSAGE_ID=None,
349 CODE_FILE=None, CODE_LINE=None, CODE_FUNC=None,
351 r"""Send a message to the journal.
353 >>> journal.send('Hello world')
354 >>> journal.send('Hello, again, world', FIELD2='Greetings!')
355 >>> journal.send('Binary message', BINARY=b'\xde\xad\xbe\xef')
357 Value of the MESSAGE argument will be used for the MESSAGE=
358 field. MESSAGE must be a string and will be sent as UTF-8 to
361 MESSAGE_ID can be given to uniquely identify the type of
362 message. It must be a string or a uuid.UUID object.
364 CODE_LINE, CODE_FILE, and CODE_FUNC can be specified to
365 identify the caller. Unless at least on of the three is given,
366 values are extracted from the stack frame of the caller of
367 send(). CODE_FILE and CODE_FUNC must be strings, CODE_LINE
370 Additional fields for the journal entry can only be specified
371 as keyword arguments. The payload can be either a string or
372 bytes. A string will be sent as UTF-8, and bytes will be sent
373 as-is to the journal.
375 Other useful fields include PRIORITY, SYSLOG_FACILITY,
376 SYSLOG_IDENTIFIER, SYSLOG_PID.
379 args = ['MESSAGE=' + MESSAGE]
381 if MESSAGE_ID is not None:
382 id = getattr(MESSAGE_ID, 'hex', MESSAGE_ID)
383 args.append('MESSAGE_ID=' + id)
385 if CODE_LINE == CODE_FILE == CODE_FUNC == None:
386 CODE_FILE, CODE_LINE, CODE_FUNC = \
387 _traceback.extract_stack(limit=2)[0][:3]
388 if CODE_FILE is not None:
389 args.append('CODE_FILE=' + CODE_FILE)
390 if CODE_LINE is not None:
391 args.append('CODE_LINE={:d}'.format(CODE_LINE))
392 if CODE_FUNC is not None:
393 args.append('CODE_FUNC=' + CODE_FUNC)
395 args.extend(_make_line(key, val) for key, val in kwargs.items())
398 def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
399 r"""Return a file object wrapping a stream to journal.
401 Log messages written to this file as simple newline sepearted
402 text strings are written to the journal.
404 The file will be line buffered, so messages are actually sent
405 after a newline character is written.
407 >>> stream = journal.stream('myapp')
409 <open file '<fdopen>', mode 'w' at 0x...>
410 >>> stream.write('message...\n')
412 will produce the following message in the journal::
415 SYSLOG_IDENTIFIER=myapp
418 Using the interface with print might be more convinient:
420 >>> from __future__ import print_function
421 >>> print('message...', file=stream)
423 priority is the syslog priority, one of `LOG_EMERG`,
424 `LOG_ALERT`, `LOG_CRIT`, `LOG_ERR`, `LOG_WARNING`,
425 `LOG_NOTICE`, `LOG_INFO`, `LOG_DEBUG`.
427 level_prefix is a boolean. If true, kernel-style log priority
428 level prefixes (such as '<1>') are interpreted. See
429 sd-daemon(3) for more information.
432 fd = stream_fd(identifier, priority, level_prefix)
433 return _os.fdopen(fd, 'w', 1)
435 class JournalHandler(_logging.Handler):
436 """Journal handler class for the Python logging framework.
438 Please see the Python logging module documentation for an
439 overview: http://docs.python.org/library/logging.html.
441 To create a custom logger whose messages go only to journal:
443 >>> log = logging.getLogger('custom_logger_name')
444 >>> log.propagate = False
445 >>> log.addHandler(journal.JournalHandler())
446 >>> log.warn("Some message: %s", detail)
448 Note that by default, message levels `INFO` and `DEBUG` are
449 ignored by the logging framework. To enable those log levels:
451 >>> log.setLevel(logging.DEBUG)
453 To attach journal MESSAGE_ID, an extra field is supported:
456 >>> mid = uuid.UUID('0123456789ABCDEF0123456789ABCDEF')
457 >>> log.warn("Message with ID", extra={'MESSAGE_ID': mid})
459 To redirect all logging messages to journal regardless of where
460 they come from, attach it to the root logger:
462 >>> logging.root.addHandler(journal.JournalHandler())
464 For more complex configurations when using `dictConfig` or
465 `fileConfig`, specify `systemd.journal.JournalHandler` as the
466 handler class. Only standard handler configuration options
467 are supported: `level`, `formatter`, `filters`.
469 The following journal fields will be sent:
470 `MESSAGE`, `PRIORITY`, `THREAD_NAME`, `CODE_FILE`, `CODE_LINE`,
471 `CODE_FUNC`, `LOGGER` (name as supplied to getLogger call),
472 `MESSAGE_ID` (optional, see above).
475 def emit(self, record):
476 """Write record as journal event.
478 MESSAGE is taken from the message provided by the
479 user, and PRIORITY, LOGGER, THREAD_NAME,
480 CODE_{FILE,LINE,FUNC} fields are appended
481 automatically. In addition, record.MESSAGE_ID will be
485 msg = self.format(record)
486 pri = self.mapPriority(record.levelno)
487 mid = getattr(record, 'MESSAGE_ID', None)
490 PRIORITY=format(pri),
492 THREAD_NAME=record.threadName,
493 CODE_FILE=record.pathname,
494 CODE_LINE=record.lineno,
495 CODE_FUNC=record.funcName)
497 self.handleError(record)
500 def mapPriority(levelno):
501 """Map logging levels to journald priorities.
503 Since Python log level numbers are "sparse", we have
504 to map numbers in between the standard levels too.
506 if levelno <= _logging.DEBUG:
508 elif levelno <= _logging.INFO:
510 elif levelno <= _logging.WARNING:
512 elif levelno <= _logging.ERROR:
514 elif levelno <= _logging.CRITICAL: