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 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 _IDENT_LETTER = set('ABCDEFGHIJKLMNOPQRTSUVWXYZ_')
101 def _valid_field_name(s):
102 return not (set(s) - _IDENT_LETTER)
104 class Reader(_Reader):
105 """Reader allows the access and filtering of systemd journal
106 entries. Note that in order to access the system journal, a
107 non-root user must be in the `systemd-journal` group.
109 Example usage to print out all informational or higher level
110 messages for systemd-udevd for this boot:
112 >>> j = journal.Reader()
114 >>> j.log_level(journal.LOG_INFO)
115 >>> j.add_match(_SYSTEMD_UNIT="systemd-udevd.service")
117 ... print(entry['MESSAGE'])
119 See systemd.journal-fields(7) for more info on typical fields
120 found in the journal.
122 def __init__(self, flags=0, path=None, converters=None):
123 """Create an instance of Reader, which allows filtering and
124 return of journal entries.
126 Argument `flags` sets open flags of the journal, which can be one
127 of, or ORed combination of constants: LOCAL_ONLY (default) opens
128 journal on local machine only; RUNTIME_ONLY opens only
129 volatile journal files; and SYSTEM_ONLY opens only
130 journal files of system services and the kernel.
132 Argument `path` is the directory of journal files. Note that
133 `flags` and `path` are exclusive.
135 Argument `converters` is a dictionary which updates the
136 DEFAULT_CONVERTERS to convert journal field values. Field
137 names are used as keys into this dictionary. The values must
138 be single argument functions, which take a `bytes` object and
139 return a converted value. When there's no entry for a field
140 name, then the default UTF-8 decoding will be attempted. If
141 the conversion fails with a ValueError, unconverted bytes
142 object will be returned. (Note that ValueEror is a superclass
143 of UnicodeDecodeError).
145 Reader implements the context manager protocol: the journal
146 will be closed when exiting the block.
148 super(Reader, self).__init__(flags, path)
149 if _sys.version_info >= (3,3):
150 self.converters = _ChainMap()
151 if converters is not None:
152 self.converters.maps.append(converters)
153 self.converters.maps.append(DEFAULT_CONVERTERS)
155 self.converters = DEFAULT_CONVERTERS.copy()
156 if converters is not None:
157 self.converters.update(converters)
159 def _convert_field(self, key, value):
160 """Convert value using self.converters[key]
162 If `key` is not present in self.converters, a standard unicode
163 decoding will be attempted. If the conversion (either
164 key-specific or the default one) fails with a ValueError, the
165 original bytes object will be returned.
167 convert = self.converters.get(key, bytes.decode)
169 return convert(value)
171 # Leave in default bytes
174 def _convert_entry(self, entry):
175 """Convert entire journal entry utilising _covert_field"""
177 for key, value in entry.items():
178 if isinstance(value, list):
179 result[key] = [self._convert_field(key, val) for val in value]
181 result[key] = self._convert_field(key, value)
185 """Part of iterator protocol.
190 if _sys.version_info >= (3,):
192 """Part of iterator protocol.
193 Returns self.get_next().
195 return self.get_next()
198 """Part of iterator protocol.
199 Returns self.get_next().
201 return self.get_next()
203 def add_match(self, *args, **kwargs):
204 """Add one or more matches to the filter journal log entries.
205 All matches of different field are combined in a logical AND,
206 and matches of the same field are automatically combined in a
208 Matches can be passed as strings of form "FIELD=value", or
209 keyword arguments FIELD="value".
212 args.extend(_make_line(key, val) for key, val in kwargs.items())
214 super(Reader, self).add_match(arg)
216 def get_next(self, skip=1):
217 """Return the next log entry as a mapping type, currently
218 a standard dictionary of fields.
220 Optional skip value will return the `skip`\-th log entry.
222 Entries will be processed with converters specified during
225 if super(Reader, self)._next(skip):
226 entry = super(Reader, self)._get_all()
228 entry['__REALTIME_TIMESTAMP'] = self._get_realtime()
229 entry['__MONOTONIC_TIMESTAMP'] = self._get_monotonic()
230 entry['__CURSOR'] = self._get_cursor()
231 return self._convert_entry(entry)
234 def get_previous(self, skip=1):
235 """Return the previous log entry as a mapping type,
236 currently a standard dictionary of fields.
238 Optional skip value will return the -`skip`\-th log entry.
240 Entries will be processed with converters specified during
243 Equivalent to get_next(-skip).
245 return self.get_next(-skip)
247 def query_unique(self, field):
248 """Return unique values appearing in the journal for given `field`.
250 Note this does not respect any journal matches.
252 Entries will be processed with converters specified during
255 return set(self._convert_field(field, value)
256 for value in super(Reader, self).query_unique(field))
258 def wait(self, timeout=None):
259 """Wait for a change in the journal. `timeout` is the maximum
260 time in seconds to wait, or None, to wait forever.
262 Returns one of NOP (no change), APPEND (new entries have been
263 added to the end of the journal), or INVALIDATE (journal files
264 have been added or removed).
266 us = -1 if timeout is None else int(timeout * 1000000)
267 return super(Reader, self).wait(us)
269 def seek_realtime(self, realtime):
270 """Seek to a matching journal entry nearest to `realtime` time.
272 Argument `realtime` must be either an integer unix timestamp
273 or datetime.datetime instance.
275 if isinstance(realtime, _datetime.datetime):
276 realtime = float(realtime.strftime("%s.%f")) * 1000000
277 return super(Reader, self).seek_realtime(int(realtime))
279 def seek_monotonic(self, monotonic, bootid=None):
280 """Seek to a matching journal entry nearest to `monotonic` time.
282 Argument `monotonic` is a timestamp from boot in either
283 seconds or a datetime.timedelta instance. Argument `bootid`
284 is a string or UUID representing which boot the monotonic time
285 is reference to. Defaults to current bootid.
287 if isinstance(monotonic, _datetime.timedelta):
288 monotonic = monotonic.totalseconds()
289 monotonic = int(monotonic * 1000000)
290 if isinstance(bootid, _uuid.UUID):
291 bootid = bootid.get_hex()
292 return super(Reader, self).seek_monotonic(monotonic, bootid)
294 def log_level(self, level):
295 """Set maximum log `level` by setting matches for PRIORITY.
298 for i in range(level+1):
299 self.add_match(PRIORITY="%d" % i)
301 raise ValueError("Log level must be 0 <= level <= 7")
303 def messageid_match(self, messageid):
304 """Add match for log entries with specified `messageid`.
306 `messageid` can be string of hexadicimal digits or a UUID
307 instance. Standard message IDs can be found in systemd.id128.
309 Equivalent to add_match(MESSAGE_ID=`messageid`).
311 if isinstance(messageid, _uuid.UUID):
312 messageid = messageid.get_hex()
313 self.add_match(MESSAGE_ID=messageid)
315 def this_boot(self, bootid=None):
316 """Add match for _BOOT_ID equal to current boot ID or the specified boot ID.
318 If specified, bootid should be either a UUID or a 32 digit hex number.
320 Equivalent to add_match(_BOOT_ID='bootid').
323 bootid = _id128.get_boot().hex
325 bootid = getattr(bootid, 'hex', bootid)
326 self.add_match(_BOOT_ID=bootid)
328 def this_machine(self, machineid=None):
329 """Add match for _MACHINE_ID equal to the ID of this machine.
331 If specified, machineid should be either a UUID or a 32 digit hex number.
333 Equivalent to add_match(_MACHINE_ID='machineid').
335 if machineid is None:
336 machineid = _id128.get_machine().hex
338 machineid = getattr(machineid, 'hex', machineid)
339 self.add_match(_MACHINE_ID=machineid)
342 def get_catalog(mid):
343 if isinstance(mid, _uuid.UUID):
345 return _get_catalog(mid)
347 def _make_line(field, value):
348 if isinstance(value, bytes):
349 return field.encode('utf-8') + b'=' + value
351 return field + '=' + value
353 def send(MESSAGE, MESSAGE_ID=None,
354 CODE_FILE=None, CODE_LINE=None, CODE_FUNC=None,
356 r"""Send a message to the journal.
358 >>> journal.send('Hello world')
359 >>> journal.send('Hello, again, world', FIELD2='Greetings!')
360 >>> journal.send('Binary message', BINARY=b'\xde\xad\xbe\xef')
362 Value of the MESSAGE argument will be used for the MESSAGE=
363 field. MESSAGE must be a string and will be sent as UTF-8 to
366 MESSAGE_ID can be given to uniquely identify the type of
367 message. It must be a string or a uuid.UUID object.
369 CODE_LINE, CODE_FILE, and CODE_FUNC can be specified to
370 identify the caller. Unless at least on of the three is given,
371 values are extracted from the stack frame of the caller of
372 send(). CODE_FILE and CODE_FUNC must be strings, CODE_LINE
375 Additional fields for the journal entry can only be specified
376 as keyword arguments. The payload can be either a string or
377 bytes. A string will be sent as UTF-8, and bytes will be sent
378 as-is to the journal.
380 Other useful fields include PRIORITY, SYSLOG_FACILITY,
381 SYSLOG_IDENTIFIER, SYSLOG_PID.
384 args = ['MESSAGE=' + MESSAGE]
386 if MESSAGE_ID is not None:
387 id = getattr(MESSAGE_ID, 'hex', MESSAGE_ID)
388 args.append('MESSAGE_ID=' + id)
390 if CODE_LINE == CODE_FILE == CODE_FUNC == None:
391 CODE_FILE, CODE_LINE, CODE_FUNC = \
392 _traceback.extract_stack(limit=2)[0][:3]
393 if CODE_FILE is not None:
394 args.append('CODE_FILE=' + CODE_FILE)
395 if CODE_LINE is not None:
396 args.append('CODE_LINE={:d}'.format(CODE_LINE))
397 if CODE_FUNC is not None:
398 args.append('CODE_FUNC=' + CODE_FUNC)
400 args.extend(_make_line(key, val) for key, val in kwargs.items())
403 def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
404 r"""Return a file object wrapping a stream to journal.
406 Log messages written to this file as simple newline sepearted
407 text strings are written to the journal.
409 The file will be line buffered, so messages are actually sent
410 after a newline character is written.
412 >>> stream = journal.stream('myapp')
414 <open file '<fdopen>', mode 'w' at 0x...>
415 >>> stream.write('message...\n')
417 will produce the following message in the journal::
420 SYSLOG_IDENTIFIER=myapp
423 Using the interface with print might be more convinient:
425 >>> from __future__ import print_function
426 >>> print('message...', file=stream)
428 priority is the syslog priority, one of `LOG_EMERG`,
429 `LOG_ALERT`, `LOG_CRIT`, `LOG_ERR`, `LOG_WARNING`,
430 `LOG_NOTICE`, `LOG_INFO`, `LOG_DEBUG`.
432 level_prefix is a boolean. If true, kernel-style log priority
433 level prefixes (such as '<1>') are interpreted. See
434 sd-daemon(3) for more information.
437 fd = stream_fd(identifier, priority, level_prefix)
438 return _os.fdopen(fd, 'w', 1)
440 class JournalHandler(_logging.Handler):
441 """Journal handler class for the Python logging framework.
443 Please see the Python logging module documentation for an
444 overview: http://docs.python.org/library/logging.html.
446 To create a custom logger whose messages go only to journal:
448 >>> log = logging.getLogger('custom_logger_name')
449 >>> log.propagate = False
450 >>> log.addHandler(journal.JournalHandler())
451 >>> log.warn("Some message: %s", detail)
453 Note that by default, message levels `INFO` and `DEBUG` are
454 ignored by the logging framework. To enable those log levels:
456 >>> log.setLevel(logging.DEBUG)
458 To redirect all logging messages to journal regardless of where
459 they come from, attach it to the root logger:
461 >>> logging.root.addHandler(journal.JournalHandler())
463 For more complex configurations when using `dictConfig` or
464 `fileConfig`, specify `systemd.journal.JournalHandler` as the
465 handler class. Only standard handler configuration options
466 are supported: `level`, `formatter`, `filters`.
468 To attach journal MESSAGE_ID, an extra field is supported:
471 >>> mid = uuid.UUID('0123456789ABCDEF0123456789ABCDEF')
472 >>> log.warn("Message with ID", extra={'MESSAGE_ID': mid})
474 Fields to be attached to all messages sent through this
475 handler can be specified as keyword arguments. This probably
476 makes sense only for SYSLOG_IDENTIFIER and similar fields
477 which are constant for the whole program:
479 >>> journal.JournalHandler(SYSLOG_IDENTIFIER='my-cool-app')
481 The following journal fields will be sent:
482 `MESSAGE`, `PRIORITY`, `THREAD_NAME`, `CODE_FILE`, `CODE_LINE`,
483 `CODE_FUNC`, `LOGGER` (name as supplied to getLogger call),
484 `MESSAGE_ID` (optional, see above), `SYSLOG_IDENTIFIER` (defaults
488 def __init__(self, level=_logging.NOTSET, **kwargs):
489 super(JournalHandler, self).__init__(level)
492 if not _valid_field_name(name):
493 raise ValueError('Invalid field name: ' + name)
494 if 'SYSLOG_IDENTIFIER' not in kwargs:
495 kwargs['SYSLOG_IDENTIFIER'] = _sys.argv[0]
498 def emit(self, record):
499 """Write record as journal event.
501 MESSAGE is taken from the message provided by the
502 user, and PRIORITY, LOGGER, THREAD_NAME,
503 CODE_{FILE,LINE,FUNC} fields are appended
504 automatically. In addition, record.MESSAGE_ID will be
508 msg = self.format(record)
509 pri = self.mapPriority(record.levelno)
510 mid = getattr(record, 'MESSAGE_ID', None)
513 PRIORITY=format(pri),
515 THREAD_NAME=record.threadName,
516 CODE_FILE=record.pathname,
517 CODE_LINE=record.lineno,
518 CODE_FUNC=record.funcName,
521 self.handleError(record)
524 def mapPriority(levelno):
525 """Map logging levels to journald priorities.
527 Since Python log level numbers are "sparse", we have
528 to map numbers in between the standard levels too.
530 if levelno <= _logging.DEBUG:
532 elif levelno <= _logging.INFO:
534 elif levelno <= _logging.WARNING:
536 elif levelno <= _logging.ERROR:
538 elif levelno <= _logging.CRITICAL: