personal/weather-server: weather_server/logfile.py annotate

annotate weather_server/logfile.py @ 21:beb42c835c52

Make weather server handle arbitrary data: - Make logfile record arbitrary BSONs - Make server handlers OK with same - Make location type a normal class rather than attrs; have it handle its own logger. - Bump version number.

author	Paul Fisher <paul@pfish.zone>
date	Sat, 19 Oct 2019 18:40:48 -0400
parents	efe7a1eff167
children	20c8ec56e447

rev	line source
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	1 """The part which handles writing things out and reading things in from CSV.
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	2 """
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	3
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	4 import concurrent.futures as futures
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	5 import contextlib
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	6 import fcntl
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	7 import os
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	8 import queue
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	9 import threading
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	10 import typing as t
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	11
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	12 import bson
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	13
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	14 from . import common
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	15
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	16
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	17 class _WriteRequest:
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	18
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	19 def __init__(self, entries: t.Iterable[t.Dict[str, t.Any]]):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	20 """Creates a request to write the given data to the log."""
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	21 # The data to be written. We take ownership of all the dicts!
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	22 self.entries = entries
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	23 # Once written, a future that will resolve to None if successful.
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	24 self.future = futures.Future()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	25
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	26
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	27 class _ReadRequest:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	28
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	29 def __init__(self):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	30 # The future that will be set with the log's contnets.
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	31 self.future = futures.Future()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	32
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	33
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	34 # probably handle file-writing with a queue that reports back its progress
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	35
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	36 class Logger:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	37 """Logger which handles reading/writing a temperature log for one process.
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	38 """
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	39
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	40 instance_lock = threading.Lock()
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	41 instances: t.Dict[str, 'Logger'] = {}
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	42
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	43 @classmethod
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	44 def create(
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	45 cls,
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	46 filename: str,
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	47 *,
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	48 sample_field: str,
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	49 ) -> 'Logger':
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	50 """Creates a single shared instance of a logger for the given file."""
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	51 try:
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	52 instance = cls.instances[filename]
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	53 except KeyError:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	54 with cls.instance_lock:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	55 try:
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	56 instance = cls.instances[filename]
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	57 except KeyError:
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	58 cls.instances[filename] = Logger(
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	59 filename,
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	60 sample_field=sample_field)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	61 instance = cls.instances[filename]
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	62 if instance._sample_field != sample_field:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	63 raise ValueError(
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	64 'Existing instance has different sample field: '
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	65 '{!r} != {!r}'.format(instance._sample_field, sample_field))
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	66 return instance
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	67
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	68 def __init__(self, filename: str, *, sample_field: str):
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	69 """You should probably call .create() instead."""
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	70 self._sample_field = sample_field
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	71 self._file = _open_or_create(filename)
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	72 self._data: t.List[t.Dict[str, t.Any], ...] = []
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	73 self._queue = queue.SimpleQueue()
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	74 self._last_size = 0
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	75 self._lock_status: t.Optional[int] = None
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	76 self._writer_thread = threading.Thread(target=self._writer)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	77 self._writer_thread.start()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	78
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	79 @property
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	80 def data(self) -> t.Tuple[t.Dict[str, t.Any], ...]:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	81 req = _ReadRequest()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	82 self._queue.put(req)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	83 return req.future.result()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	84
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	85 def write_rows(self, entries: t.Iterable[t.Dict[str, t.Any]]):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	86 req = _WriteRequest(entries)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	87 self._queue.put(req)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	88 return req.future.result()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	89
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	90 _POISON = object()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	91
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	92 def close(self):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	93 self._queue.put(self._POISON)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	94 self._writer_thread.join()
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	95
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	96 def _writer(self) -> None:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	97 running = True
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	98 while running:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	99 item = self._queue.get()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	100 if item is self._POISON:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	101 # None is the poison pill that makes us stop.
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	102 running = False
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	103 elif isinstance(item, _ReadRequest):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	104 if not item.future.set_running_or_notify_cancel():
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	105 continue
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	106 try:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	107 with self._file_lock(fcntl.LOCK_SH):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	108 self._catch_up()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	109 except BaseException as x:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	110 item.future.set_exception(x)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	111 else:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	112 item.future.set_result(tuple(self._data))
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	113 elif isinstance(item, _WriteRequest):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	114 if not item.future.set_running_or_notify_cancel():
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	115 continue
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	116 try:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	117 with self._file_lock(fcntl.LOCK_EX):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	118 self._catch_up()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	119 # Since we're at the last good point, truncate after.
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	120 self._file.truncate(self._file.tell())
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	121 if not self._data:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	122 last = None
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	123 else:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	124 last = self._data[-1][self._sample_field]
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	125 for entry in item.entries:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	126 entry_key = entry[self._sample_field]
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	127 if last is None or last < entry_key:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	128 self._file.write(common.bson_encode(entry))
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	129 self._data.append(entry)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	130 last = entry_key
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	131 self._file.flush()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	132 self._last_size = self._file.tell()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	133 except BaseException as x:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	134 item.future.set_exception(x)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	135 else:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	136 item.future.set_result(None)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	137 else:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	138 raise AssertionError(
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	139 'Unexpected item {!r} in the queue'.format(item))
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	140 self._file.close()
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	141
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	142 def _catch_up(self) -> None:
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	143 """Reads data and advances the file pointer to the end of the file."""
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	144 assert self._lock_status is not None, 'The lock must be held.'
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	145 size = self._size()
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	146 if size == self._last_size:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	147 return
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	148 last_good = self._file.tell()
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	149 try:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	150 items = bson.decode_file_iter(
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	151 self._file, codec_options=common.BSON_OPTIONS)
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	152 for item in items:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	153 last_good = self._file.tell()
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	154 self._data.append(item)
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	155 except bson.InvalidBSON:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	156 pass # We have reached the last valid document. Bail.
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	157 # Seek back to immediately after the end of the last valid doc.
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	158 self._last_size = last_good
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	159 self._file.seek(last_good, os.SEEK_SET)
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	160
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	161 def fileno(self) -> int:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	162 return self._file.fileno()
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	163
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	164 def _size(self) -> int:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	165 return os.stat(self.fileno()).st_size
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	166
21 beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	167 @contextlib.contextmanager
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	168 def _file_lock(self, operation: int):
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	169 assert operation in (fcntl.LOCK_SH, fcntl.LOCK_EX), 'Invalid operation.'
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	170 fcntl.flock(self, operation)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	171 self._lock_status = operation
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	172 try:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	173 yield
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	174 finally:
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	175 self._lock_status = None
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	176 fcntl.flock(self, fcntl.LOCK_UN)
beb42c835c52 Make weather server handle arbitrary data: Paul Fisher <paul@pfish.zone> parents: 0 diff changeset	177
0 efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	178
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	179 def _open_or_create(path: str) -> t.BinaryIO:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	180 while True:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	181 try:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	182 return open(path, 'r+b')
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	183 except FileNotFoundError:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	184 pass
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	185 try:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	186 return open(path, 'x+b')
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	187 except FileExistsError:
efe7a1eff167 Create initial logger for weather server. Paul Fisher <paul@pfish.zone> parents: diff changeset	188 pass

Mercurial > personal > weather-server

annotate weather_server/logfile.py @ 21:beb42c835c52