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)
179 def add_match(self, *args, **kwargs):
180 """Add one or more matches to the filter journal log entries.
181 All matches of different field are combined in a logical AND,
182 and matches of the same field are automatically combined in a
184 Matches can be passed as strings of form "FIELD=value", or
185 keyword arguments FIELD="value".
188 args.extend(_make_line(key, val) for key, val in kwargs.items())
190 super(Reader, self).add_match(arg)
192 def get_next(self, skip=1):
193 """Return the next log entry as a dictionary of fields.
195 Optional skip value will return the `skip`\-th log entry.
197 Entries will be processed with converters specified during
200 return self._convert_entry(
201 super(Reader, self).get_next(skip))
203 def query_unique(self, field):
204 """Return unique values appearing in the journal for given `field`.
206 Note this does not respect any journal matches.
208 Entries will be processed with converters specified during
211 return set(self._convert_field(field, value)
212 for value in super(Reader, self).query_unique(field))
214 def wait(self, timeout=None):
215 """Wait for a change in the journal. `timeout` is the maximum
216 time in seconds to wait, or None, to wait forever.
218 Returns one of NOP (no change), APPEND (new entries have been
219 added to the end of the journal), or INVALIDATE (journal files
220 have been added or removed).
222 us = -1 if timeout is None else int(timeout * 1000000)
223 return super(Reader, self).wait(us)
225 def seek_realtime(self, realtime):
226 """Seek to a matching journal entry nearest to `realtime` time.
228 Argument `realtime` must be either an integer unix timestamp
229 or datetime.datetime instance.
231 if isinstance(realtime, _datetime.datetime):
232 realtime = float(realtime.strftime("%s.%f")) * 1000000
233 return super(Reader, self).seek_realtime(int(realtime))
235 def seek_monotonic(self, monotonic, bootid=None):
236 """Seek to a matching journal entry nearest to `monotonic` time.
238 Argument `monotonic` is a timestamp from boot in either
239 seconds or a datetime.timedelta instance. Argument `bootid`
240 is a string or UUID representing which boot the monotonic time
241 is reference to. Defaults to current bootid.
243 if isinstance(monotonic, _datetime.timedelta):
244 monotonic = monotonic.totalseconds()
245 monotonic = int(monotonic * 1000000)
246 if isinstance(bootid, _uuid.UUID):
247 bootid = bootid.get_hex()
248 return super(Reader, self).seek_monotonic(monotonic, bootid)
250 def log_level(self, level):
251 """Set maximum log `level` by setting matches for PRIORITY.
254 for i in range(level+1):
255 self.add_match(PRIORITY="%d" % i)
257 raise ValueError("Log level must be 0 <= level <= 7")
259 def messageid_match(self, messageid):
260 """Add match for log entries with specified `messageid`.
262 `messageid` can be string of hexadicimal digits or a UUID
263 instance. Standard message IDs can be found in systemd.id128.
265 Equivalent to add_match(MESSAGE_ID=`messageid`).
267 if isinstance(messageid, _uuid.UUID):
268 messageid = messageid.get_hex()
269 self.add_match(MESSAGE_ID=messageid)
271 def this_boot(self, bootid=None):
272 """Add match for _BOOT_ID equal to current boot ID or the specified boot ID.
274 If specified, bootid should be either a UUID or a 32 digit hex number.
276 Equivalent to add_match(_BOOT_ID='bootid').
279 bootid = _id128.get_boot().hex
281 bootid = getattr(bootid, 'hex', bootid)
282 self.add_match(_BOOT_ID=bootid)
284 def this_machine(self, machineid=None):
285 """Add match for _MACHINE_ID equal to the ID of this machine.
287 If specified, machineid should be either a UUID or a 32 digit hex number.
289 Equivalent to add_match(_MACHINE_ID='machineid').
291 if machineid is None:
292 machineid = _id128.get_machine().hex
294 machineid = getattr(machineid, 'hex', machineid)
295 self.add_match(_MACHINE_ID=machineid)
298 def get_catalog(mid):
299 if isinstance(mid, _uuid.UUID):
301 return _get_catalog(mid)
303 def _make_line(field, value):
304 if isinstance(value, bytes):
305 return field.encode('utf-8') + b'=' + value
307 return field + '=' + value
309 def send(MESSAGE, MESSAGE_ID=None,
310 CODE_FILE=None, CODE_LINE=None, CODE_FUNC=None,
312 r"""Send a message to the journal.
314 >>> journal.send('Hello world')
315 >>> journal.send('Hello, again, world', FIELD2='Greetings!')
316 >>> journal.send('Binary message', BINARY=b'\xde\xad\xbe\xef')
318 Value of the MESSAGE argument will be used for the MESSAGE=
319 field. MESSAGE must be a string and will be sent as UTF-8 to
322 MESSAGE_ID can be given to uniquely identify the type of
323 message. It must be a string or a uuid.UUID object.
325 CODE_LINE, CODE_FILE, and CODE_FUNC can be specified to
326 identify the caller. Unless at least on of the three is given,
327 values are extracted from the stack frame of the caller of
328 send(). CODE_FILE and CODE_FUNC must be strings, CODE_LINE
331 Additional fields for the journal entry can only be specified
332 as keyword arguments. The payload can be either a string or
333 bytes. A string will be sent as UTF-8, and bytes will be sent
334 as-is to the journal.
336 Other useful fields include PRIORITY, SYSLOG_FACILITY,
337 SYSLOG_IDENTIFIER, SYSLOG_PID.
340 args = ['MESSAGE=' + MESSAGE]
342 if MESSAGE_ID is not None:
343 id = getattr(MESSAGE_ID, 'hex', MESSAGE_ID)
344 args.append('MESSAGE_ID=' + id)
346 if CODE_LINE == CODE_FILE == CODE_FUNC == None:
347 CODE_FILE, CODE_LINE, CODE_FUNC = \
348 _traceback.extract_stack(limit=2)[0][:3]
349 if CODE_FILE is not None:
350 args.append('CODE_FILE=' + CODE_FILE)
351 if CODE_LINE is not None:
352 args.append('CODE_LINE={:d}'.format(CODE_LINE))
353 if CODE_FUNC is not None:
354 args.append('CODE_FUNC=' + CODE_FUNC)
356 args.extend(_make_line(key, val) for key, val in kwargs.items())
359 def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
360 r"""Return a file object wrapping a stream to journal.
362 Log messages written to this file as simple newline sepearted
363 text strings are written to the journal.
365 The file will be line buffered, so messages are actually sent
366 after a newline character is written.
368 >>> stream = journal.stream('myapp')
370 <open file '<fdopen>', mode 'w' at 0x...>
371 >>> stream.write('message...\n')
373 will produce the following message in the journal::
376 SYSLOG_IDENTIFIER=myapp
379 Using the interface with print might be more convinient:
381 >>> from __future__ import print_function
382 >>> print('message...', file=stream)
384 priority is the syslog priority, one of `LOG_EMERG`,
385 `LOG_ALERT`, `LOG_CRIT`, `LOG_ERR`, `LOG_WARNING`,
386 `LOG_NOTICE`, `LOG_INFO`, `LOG_DEBUG`.
388 level_prefix is a boolean. If true, kernel-style log priority
389 level prefixes (such as '<1>') are interpreted. See
390 sd-daemon(3) for more information.
393 fd = stream_fd(identifier, priority, level_prefix)
394 return _os.fdopen(fd, 'w', 1)
396 class JournalHandler(_logging.Handler):
397 """Journal handler class for the Python logging framework.
399 Please see the Python logging module documentation for an
400 overview: http://docs.python.org/library/logging.html.
402 To create a custom logger whose messages go only to journal:
404 >>> log = logging.getLogger('custom_logger_name')
405 >>> log.propagate = False
406 >>> log.addHandler(journal.JournalHandler())
407 >>> log.warn("Some message: %s", detail)
409 Note that by default, message levels `INFO` and `DEBUG` are
410 ignored by the logging framework. To enable those log levels:
412 >>> log.setLevel(logging.DEBUG)
414 To attach journal MESSAGE_ID, an extra field is supported:
417 >>> mid = uuid.UUID('0123456789ABCDEF0123456789ABCDEF')
418 >>> log.warn("Message with ID", extra={'MESSAGE_ID': mid})
420 To redirect all logging messages to journal regardless of where
421 they come from, attach it to the root logger:
423 >>> logging.root.addHandler(journal.JournalHandler())
425 For more complex configurations when using `dictConfig` or
426 `fileConfig`, specify `systemd.journal.JournalHandler` as the
427 handler class. Only standard handler configuration options
428 are supported: `level`, `formatter`, `filters`.
430 The following journal fields will be sent:
431 `MESSAGE`, `PRIORITY`, `THREAD_NAME`, `CODE_FILE`, `CODE_LINE`,
432 `CODE_FUNC`, `LOGGER` (name as supplied to getLogger call),
433 `MESSAGE_ID` (optional, see above).
436 def emit(self, record):
437 """Write record as journal event.
439 MESSAGE is taken from the message provided by the
440 user, and PRIORITY, LOGGER, THREAD_NAME,
441 CODE_{FILE,LINE,FUNC} fields are appended
442 automatically. In addition, record.MESSAGE_ID will be
446 msg = self.format(record)
447 pri = self.mapPriority(record.levelno)
448 mid = getattr(record, 'MESSAGE_ID', None)
451 PRIORITY=format(pri),
453 THREAD_NAME=record.threadName,
454 CODE_FILE=record.pathname,
455 CODE_LINE=record.lineno,
456 CODE_FUNC=record.funcName)
458 self.handleError(record)
461 def mapPriority(levelno):
462 """Map logging levels to journald priorities.
464 Since Python log level numbers are "sparse", we have
465 to map numbers in between the standard levels too.
467 if levelno <= _logging.DEBUG:
469 elif levelno <= _logging.INFO:
471 elif levelno <= _logging.WARNING:
473 elif levelno <= _logging.ERROR:
475 elif levelno <= _logging.CRITICAL: