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 Reader implements the context manager protocol: the journal
142 will be closed when exiting the block.
144 super(Reader, self).__init__(flags, path)
145 if _sys.version_info >= (3,3):
146 self.converters = _ChainMap()
147 if converters is not None:
148 self.converters.maps.append(converters)
149 self.converters.maps.append(DEFAULT_CONVERTERS)
151 self.converters = DEFAULT_CONVERTERS.copy()
152 if converters is not None:
153 self.converters.update(converters)
155 def _convert_field(self, key, value):
156 """Convert value using self.converters[key]
158 If `key` is not present in self.converters, a standard unicode
159 decoding will be attempted. If the conversion (either
160 key-specific or the default one) fails with a ValueError, the
161 original bytes object will be returned.
163 convert = self.converters.get(key, bytes.decode)
165 return convert(value)
167 # Leave in default bytes
170 def _convert_entry(self, entry):
171 """Convert entire journal entry utilising _covert_field"""
173 for key, value in entry.items():
174 if isinstance(value, list):
175 result[key] = [self._convert_field(key, val) for val in value]
177 result[key] = self._convert_field(key, value)
180 def add_match(self, *args, **kwargs):
181 """Add one or more matches to the filter journal log entries.
182 All matches of different field are combined in a logical AND,
183 and matches of the same field are automatically combined in a
185 Matches can be passed as strings of form "FIELD=value", or
186 keyword arguments FIELD="value".
189 args.extend(_make_line(key, val) for key, val in kwargs.items())
191 super(Reader, self).add_match(arg)
193 def get_next(self, skip=1):
194 """Return the next log entry as a dictionary of fields.
196 Optional skip value will return the `skip`\-th log entry.
198 Entries will be processed with converters specified during
201 return self._convert_entry(
202 super(Reader, self).get_next(skip))
204 def query_unique(self, field):
205 """Return unique values appearing in the journal for given `field`.
207 Note this does not respect any journal matches.
209 Entries will be processed with converters specified during
212 return set(self._convert_field(field, value)
213 for value in super(Reader, self).query_unique(field))
215 def wait(self, timeout=None):
216 """Wait for a change in the journal. `timeout` is the maximum
217 time in seconds to wait, or None, to wait forever.
219 Returns one of NOP (no change), APPEND (new entries have been
220 added to the end of the journal), or INVALIDATE (journal files
221 have been added or removed).
223 us = -1 if timeout is None else int(timeout * 1000000)
224 return super(Reader, self).wait(timeout)
226 def seek_realtime(self, realtime):
227 """Seek to a matching journal entry nearest to `realtime` time.
229 Argument `realtime` must be either an integer unix timestamp
230 or datetime.datetime instance.
232 if isinstance(realtime, _datetime.datetime):
233 realtime = float(realtime.strftime("%s.%f")) * 1000000
234 return super(Reader, self).seek_realtime(int(realtime))
236 def seek_monotonic(self, monotonic, bootid=None):
237 """Seek to a matching journal entry nearest to `monotonic` time.
239 Argument `monotonic` is a timestamp from boot in either
240 seconds or a datetime.timedelta instance. Argument `bootid`
241 is a string or UUID representing which boot the monotonic time
242 is reference to. Defaults to current bootid.
244 if isinstance(monotonic, _datetime.timedelta):
245 monotonic = monotonic.totalseconds()
246 monotonic = int(monotonic * 1000000)
247 if isinstance(bootid, _uuid.UUID):
248 bootid = bootid.get_hex()
249 return super(Reader, self).seek_monotonic(monotonic, bootid)
251 def log_level(self, level):
252 """Set maximum log `level` by setting matches for PRIORITY.
255 for i in range(level+1):
256 self.add_match(PRIORITY="%d" % i)
258 raise ValueError("Log level must be 0 <= level <= 7")
260 def messageid_match(self, messageid):
261 """Add match for log entries with specified `messageid`.
263 `messageid` can be string of hexadicimal digits or a UUID
264 instance. Standard message IDs can be found in systemd.id128.
266 Equivalent to add_match(MESSAGE_ID=`messageid`).
268 if isinstance(messageid, _uuid.UUID):
269 messageid = messageid.get_hex()
270 self.add_match(MESSAGE_ID=messageid)
272 def this_boot(self, bootid=None):
273 """Add match for _BOOT_ID equal to current boot ID or the specified boot ID.
275 If specified, bootid should be either a UUID or a 32 digit hex number.
277 Equivalent to add_match(_BOOT_ID='bootid').
280 bootid = _id128.get_boot().hex
282 bootid = getattr(bootid, 'hex', bootid)
283 self.add_match(_BOOT_ID=bootid)
285 def this_machine(self, machineid=None):
286 """Add match for _MACHINE_ID equal to the ID of this machine.
288 If specified, machineid should be either a UUID or a 32 digit hex number.
290 Equivalent to add_match(_MACHINE_ID='machineid').
292 if machineid is None:
293 machineid = _id128.get_machine().hex
295 machineid = getattr(machineid, 'hex', machineid)
296 self.add_match(_MACHINE_ID=machineid)
299 def get_catalog(mid):
300 if isinstance(mid, _uuid.UUID):
302 return _get_catalog(mid)
304 def _make_line(field, value):
305 if isinstance(value, bytes):
306 return field.encode('utf-8') + b'=' + value
308 return field + '=' + value
310 def send(MESSAGE, MESSAGE_ID=None,
311 CODE_FILE=None, CODE_LINE=None, CODE_FUNC=None,
313 r"""Send a message to the journal.
315 >>> journal.send('Hello world')
316 >>> journal.send('Hello, again, world', FIELD2='Greetings!')
317 >>> journal.send('Binary message', BINARY=b'\xde\xad\xbe\xef')
319 Value of the MESSAGE argument will be used for the MESSAGE=
320 field. MESSAGE must be a string and will be sent as UTF-8 to
323 MESSAGE_ID can be given to uniquely identify the type of
324 message. It must be a string or a uuid.UUID object.
326 CODE_LINE, CODE_FILE, and CODE_FUNC can be specified to
327 identify the caller. Unless at least on of the three is given,
328 values are extracted from the stack frame of the caller of
329 send(). CODE_FILE and CODE_FUNC must be strings, CODE_LINE
332 Additional fields for the journal entry can only be specified
333 as keyword arguments. The payload can be either a string or
334 bytes. A string will be sent as UTF-8, and bytes will be sent
335 as-is to the journal.
337 Other useful fields include PRIORITY, SYSLOG_FACILITY,
338 SYSLOG_IDENTIFIER, SYSLOG_PID.
341 args = ['MESSAGE=' + MESSAGE]
343 if MESSAGE_ID is not None:
344 id = getattr(MESSAGE_ID, 'hex', MESSAGE_ID)
345 args.append('MESSAGE_ID=' + id)
347 if CODE_LINE == CODE_FILE == CODE_FUNC == None:
348 CODE_FILE, CODE_LINE, CODE_FUNC = \
349 _traceback.extract_stack(limit=2)[0][:3]
350 if CODE_FILE is not None:
351 args.append('CODE_FILE=' + CODE_FILE)
352 if CODE_LINE is not None:
353 args.append('CODE_LINE={:d}'.format(CODE_LINE))
354 if CODE_FUNC is not None:
355 args.append('CODE_FUNC=' + CODE_FUNC)
357 args.extend(_make_line(key, val) for key, val in kwargs.items())
360 def stream(identifier, priority=LOG_DEBUG, level_prefix=False):
361 r"""Return a file object wrapping a stream to journal.
363 Log messages written to this file as simple newline sepearted
364 text strings are written to the journal.
366 The file will be line buffered, so messages are actually sent
367 after a newline character is written.
369 >>> stream = journal.stream('myapp')
371 <open file '<fdopen>', mode 'w' at 0x...>
372 >>> stream.write('message...\n')
374 will produce the following message in the journal::
377 SYSLOG_IDENTIFIER=myapp
380 Using the interface with print might be more convinient:
382 >>> from __future__ import print_function
383 >>> print('message...', file=stream)
385 priority is the syslog priority, one of `LOG_EMERG`,
386 `LOG_ALERT`, `LOG_CRIT`, `LOG_ERR`, `LOG_WARNING`,
387 `LOG_NOTICE`, `LOG_INFO`, `LOG_DEBUG`.
389 level_prefix is a boolean. If true, kernel-style log priority
390 level prefixes (such as '<1>') are interpreted. See
391 sd-daemon(3) for more information.
394 fd = stream_fd(identifier, priority, level_prefix)
395 return _os.fdopen(fd, 'w', 1)
397 class JournalHandler(_logging.Handler):
398 """Journal handler class for the Python logging framework.
400 Please see the Python logging module documentation for an
401 overview: http://docs.python.org/library/logging.html.
403 To create a custom logger whose messages go only to journal:
405 >>> log = logging.getLogger('custom_logger_name')
406 >>> log.propagate = False
407 >>> log.addHandler(journal.JournalHandler())
408 >>> log.warn("Some message: %s", detail)
410 Note that by default, message levels `INFO` and `DEBUG` are
411 ignored by the logging framework. To enable those log levels:
413 >>> log.setLevel(logging.DEBUG)
415 To attach journal MESSAGE_ID, an extra field is supported:
418 >>> mid = uuid.UUID('0123456789ABCDEF0123456789ABCDEF')
419 >>> log.warn("Message with ID", extra={'MESSAGE_ID': mid})
421 To redirect all logging messages to journal regardless of where
422 they come from, attach it to the root logger:
424 >>> logging.root.addHandler(journal.JournalHandler())
426 For more complex configurations when using `dictConfig` or
427 `fileConfig`, specify `systemd.journal.JournalHandler` as the
428 handler class. Only standard handler configuration options
429 are supported: `level`, `formatter`, `filters`.
431 The following journal fields will be sent:
432 `MESSAGE`, `PRIORITY`, `THREAD_NAME`, `CODE_FILE`, `CODE_LINE`,
433 `CODE_FUNC`, `LOGGER` (name as supplied to getLogger call),
434 `MESSAGE_ID` (optional, see above).
437 def emit(self, record):
438 """Write record as journal event.
440 MESSAGE is taken from the message provided by the
441 user, and PRIORITY, LOGGER, THREAD_NAME,
442 CODE_{FILE,LINE,FUNC} fields are appended
443 automatically. In addition, record.MESSAGE_ID will be
447 msg = self.format(record)
448 pri = self.mapPriority(record.levelno)
449 mid = getattr(record, 'MESSAGE_ID', None)
452 PRIORITY=format(pri),
454 THREAD_NAME=record.threadName,
455 CODE_FILE=record.pathname,
456 CODE_LINE=record.lineno,
457 CODE_FUNC=record.funcName)
459 self.handleError(record)
462 def mapPriority(levelno):
463 """Map logging levels to journald priorities.
465 Since Python log level numbers are "sparse", we have
466 to map numbers in between the standard levels too.
468 if levelno <= _logging.DEBUG:
470 elif levelno <= _logging.INFO:
472 elif levelno <= _logging.WARNING:
474 elif levelno <= _logging.ERROR:
476 elif levelno <= _logging.CRITICAL: