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,
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 if _sys.version_info >= (3,):
61 return _uuid.UUID(s.decode())
63 _convert_uuid = _uuid.UUID
65 DEFAULT_CONVERTERS = {
66 'MESSAGE_ID': _convert_uuid,
67 '_MACHINE_ID': _convert_uuid,
68 '_BOOT_ID': _convert_uuid,
72 'USERSPACE_USEC': int,
78 'SYSLOG_FACILITY': int,
80 '_AUDIT_SESSION': int,
81 '_AUDIT_LOGINUID': int,
82 '_SYSTEMD_SESSION': int,
83 '_SYSTEMD_OWNER_UID': int,
87 '_SOURCE_REALTIME_TIMESTAMP': _convert_timestamp,
88 '__REALTIME_TIMESTAMP': _convert_realtime,
89 '_SOURCE_MONOTONIC_TIMESTAMP': _convert_source_monotonic,
90 '__MONOTONIC_TIMESTAMP': _convert_monotonic,
95 'COREDUMP_SESSION': int,
96 'COREDUMP_SIGNAL': int,
97 'COREDUMP_TIMESTAMP': _convert_timestamp,
100 class Reader(_Reader):
101 """Reader allows the access and filtering of systemd journal
102 entries. Note that in order to access the system journal, a
103 non-root user must be in the `systemd-journal` group.
105 Example usage to print out all informational or higher level
106 messages for systemd-udevd for this boot:
108 >>> j = journal.Reader()
110 >>> j.log_level(journal.LOG_INFO)
111 >>> j.add_match(_SYSTEMD_UNIT="systemd-udevd.service")
113 ... print(entry['MESSAGE'])
115 See systemd.journal-fields(7) for more info on typical fields
116 found in the journal.
118 def __init__(self, flags=0, path=None, converters=None):
119 """Create an instance of Reader, which allows filtering and
120 return of journal entries.
122 Argument `flags` sets open flags of the journal, which can be one
123 of, or ORed combination of constants: LOCAL_ONLY (default) opens
124 journal on local machine only; RUNTIME_ONLY opens only
125 volatile journal files; and SYSTEM_ONLY opens only
126 journal files of system services and the kernel.
128 Argument `path` is the directory of journal files. Note that
129 `flags` and `path` are exclusive.
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 wait(self, timeout=None):
213 """Wait for a change in the journal. `timeout` is the maximum
214 time in seconds to wait, or None, to wait forever.
216 Returns one of NOP (no change), APPEND (new entries have been
217 added to the end of the journal), or INVALIDATE (journal files
218 have been added or removed).
220 us = -1 if timeout is None else int(timeout * 1000000)
221 return super(Reader, self).wait(timeout)
223 def seek_realtime(self, realtime):
224 """Seek to a matching journal entry nearest to `realtime` time.
226 Argument `realtime` must be either an integer unix timestamp
227 or datetime.datetime instance.
229 if isinstance(realtime, _datetime.datetime):
230 realtime = float(realtime.strftime("%s.%f")) * 1000000
231 return super(Reader, self).seek_realtime(int(realtime))
233 def seek_monotonic(self, monotonic, bootid=None):
234 """Seek to a matching journal entry nearest to `monotonic` time.
236 Argument `monotonic` is a timestamp from boot in either
237 seconds or a datetime.timedelta instance. Argument `bootid`
238 is a string or UUID representing which boot the monotonic time
239 is reference to. Defaults to current bootid.
241 if isinstance(monotonic, _datetime.timedelta):
242 monotonic = monotonic.totalseconds()
243 monotonic = int(monotonic * 1000000)
244 if isinstance(bootid, _uuid.UUID):
245 bootid = bootid.get_hex()
246 return super(Reader, self).seek_monotonic(monotonic, bootid)
248 def log_level(self, level):
249 """Set maximum log `level` by setting matches for PRIORITY.
252 for i in range(level+1):
253 self.add_match(PRIORITY="%d" % i)
255 raise ValueError("Log level must be 0 <= level <= 7")
257 def messageid_match(self, messageid):
258 """Add match for log entries with specified `messageid`.
260 `messageid` can be string of hexadicimal digits or a UUID
261 instance. Standard message IDs can be found in systemd.id128.
263 Equivalent to add_match(MESSAGE_ID=`messageid`).
265 if isinstance(messageid, _uuid.UUID):
266 messageid = messageid.get_hex()
267 self.add_match(MESSAGE_ID=messageid)
269 def this_boot(self, bootid=None):
270 """Add match for _BOOT_ID equal to current boot ID or the specified boot ID.
272 If specified, bootid should be either a UUID or a 32 digit hex number.
274 Equivalent to add_match(_BOOT_ID='bootid').
277 bootid = _id128.get_boot().hex
279 bootid = getattr(bootid, 'hex', bootid)
280 self.add_match(_BOOT_ID=bootid)
282 def this_machine(self, machineid=None):
283 """Add match for _MACHINE_ID equal to the ID of this machine.
285 If specified, machineid should be either a UUID or a 32 digit hex number.
287 Equivalent to add_match(_MACHINE_ID='machineid').
289 if machineid is None:
290 machineid = _id128.get_machine().hex
292 machineid = getattr(machineid, 'hex', machineid)
293 self.add_match(_MACHINE_ID=machineid)
296 def _make_line(field, value):
297 if isinstance(value, bytes):
298 return field.encode('utf-8') + b'=' + value
300 return field + '=' + value
302 def send(MESSAGE, MESSAGE_ID=None,
303 CODE_FILE=None, CODE_LINE=None, CODE_FUNC=None,
305 r"""Send a message to the journal.
307 >>> journal.send('Hello world')
308 >>> journal.send('Hello, again, world', FIELD2='Greetings!')
309 >>> journal.send('Binary message', BINARY=b'\xde\xad\xbe\xef')
311 Value of the MESSAGE argument will be used for the MESSAGE=
312 field. MESSAGE must be a string and will be sent as UTF-8 to
315 MESSAGE_ID can be given to uniquely identify the type of
316 message. It must be a string or a uuid.UUID object.
318 CODE_LINE, CODE_FILE, and CODE_FUNC can be specified to
319 identify the caller. Unless at least on of the three is given,
320 values are extracted from the stack frame of the caller of
321 send(). CODE_FILE and CODE_FUNC must be strings, CODE_LINE
324 Additional fields for the journal entry can only be specified
325 as keyword arguments. The payload can be either a string or
326 bytes. A string will be sent as UTF-8, and bytes will be sent
327 as-is to the journal.
329 Other useful fields include PRIORITY, SYSLOG_FACILITY,
330 SYSLOG_IDENTIFIER, SYSLOG_PID.
333 args = ['MESSAGE=' + MESSAGE]
335 if MESSAGE_ID is not None:
336 id = getattr(MESSAGE_ID, 'hex', MESSAGE_ID)
337 args.append('MESSAGE_ID=' + id)
339 if CODE_LINE == CODE_FILE == CODE_FUNC == None:
340 CODE_FILE, CODE_LINE, CODE_FUNC = \
341 _traceback.extract_stack(limit=2)[0][:3]
342 if CODE_FILE is not None:
343 args.append('CODE_FILE=' + CODE_FILE)
344 if CODE_LINE is not None:
345 args.append('CODE_LINE={:d}'.format(CODE_LINE))
346 if CODE_FUNC is not None:
347 args.append('CODE_FUNC=' + CODE_FUNC)
349 args.extend(_make_line(key, val) for key, val in kwargs.items())
352 def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
353 r"""Return a file object wrapping a stream to journal.
355 Log messages written to this file as simple newline sepearted
356 text strings are written to the journal.
358 The file will be line buffered, so messages are actually sent
359 after a newline character is written.
361 >>> stream = journal.stream('myapp')
363 <open file '<fdopen>', mode 'w' at 0x...>
364 >>> stream.write('message...\n')
366 will produce the following message in the journal::
369 SYSLOG_IDENTIFIER=myapp
372 Using the interface with print might be more convinient:
374 >>> from __future__ import print_function
375 >>> print('message...', file=stream)
377 priority is the syslog priority, one of `LOG_EMERG`,
378 `LOG_ALERT`, `LOG_CRIT`, `LOG_ERR`, `LOG_WARNING`,
379 `LOG_NOTICE`, `LOG_INFO`, `LOG_DEBUG`.
381 level_prefix is a boolean. If true, kernel-style log priority
382 level prefixes (such as '<1>') are interpreted. See
383 sd-daemon(3) for more information.
386 fd = stream_fd(identifier, priority, level_prefix)
387 return _os.fdopen(fd, 'w', 1)
389 class JournalHandler(_logging.Handler):
390 """Journal handler class for the Python logging framework.
392 Please see the Python logging module documentation for an
393 overview: http://docs.python.org/library/logging.html.
395 To create a custom logger whose messages go only to journal:
397 >>> log = logging.getLogger('custom_logger_name')
398 >>> log.propagate = False
399 >>> log.addHandler(journal.JournalHandler())
400 >>> log.warn("Some message: %s", detail)
402 Note that by default, message levels `INFO` and `DEBUG` are
403 ignored by the logging framework. To enable those log levels:
405 >>> log.setLevel(logging.DEBUG)
407 To attach journal MESSAGE_ID, an extra field is supported:
410 >>> mid = uuid.UUID('0123456789ABCDEF0123456789ABCDEF')
411 >>> log.warn("Message with ID", extra={'MESSAGE_ID': mid})
413 To redirect all logging messages to journal regardless of where
414 they come from, attach it to the root logger:
416 >>> logging.root.addHandler(journal.JournalHandler())
418 For more complex configurations when using `dictConfig` or
419 `fileConfig`, specify `systemd.journal.JournalHandler` as the
420 handler class. Only standard handler configuration options
421 are supported: `level`, `formatter`, `filters`.
423 The following journal fields will be sent:
424 `MESSAGE`, `PRIORITY`, `THREAD_NAME`, `CODE_FILE`, `CODE_LINE`,
425 `CODE_FUNC`, `LOGGER` (name as supplied to getLogger call),
426 `MESSAGE_ID` (optional, see above).
429 def emit(self, record):
430 """Write record as journal event.
432 MESSAGE is taken from the message provided by the
433 user, and PRIORITY, LOGGER, THREAD_NAME,
434 CODE_{FILE,LINE,FUNC} fields are appended
435 automatically. In addition, record.MESSAGE_ID will be
439 msg = self.format(record)
440 pri = self.mapPriority(record.levelno)
441 mid = getattr(record, 'MESSAGE_ID', None)
444 PRIORITY=format(pri),
446 THREAD_NAME=record.threadName,
447 CODE_FILE=record.pathname,
448 CODE_LINE=record.lineno,
449 CODE_FUNC=record.funcName)
451 self.handleError(record)
454 def mapPriority(levelno):
455 """Map logging levels to journald priorities.
457 Since Python log level numbers are "sparse", we have
458 to map numbers in between the standard levels too.
460 if levelno <= _logging.DEBUG:
462 elif levelno <= _logging.INFO:
464 elif levelno <= _logging.WARNING:
466 elif levelno <= _logging.ERROR:
468 elif levelno <= _logging.CRITICAL: