| 1 | # -*- coding: utf-8 -*- |
| 2 | # Description: |
| 3 | # SPDX-License-Identifier: GPL-3.0-or-later |
| 4 | |
| 5 | from glob import glob |
| 6 | import sys |
| 7 | import os |
| 8 | |
| 9 | from bases.FrameworkServices.SimpleService import SimpleService |
| 10 | |
| 11 | |
| 12 | class LogService(SimpleService): |
| 13 | def __init__(self, configuration=None, name=None): |
| 14 | SimpleService.__init__(self, configuration=configuration, name=name) |
| 15 | self.log_path = self.configuration.get('path') |
| 16 | self.__glob_path = self.log_path |
| 17 | self._last_position = 0 |
| 18 | self.__re_find = dict(current=0, run=0, maximum=60) |
| 19 | self.__open_args = {'errors': 'replace'} if sys.version_info[0] > 2 else {} |
| 20 | |
| 21 | def _get_raw_data(self): |
| 22 | """ |
| 23 | Get log lines since last poll |
| 24 | :return: list |
| 25 | """ |
| 26 | lines = list() |
| 27 | try: |
| 28 | if self.__re_find['current'] == self.__re_find['run']: |
| 29 | self._find_recent_log_file() |
| 30 | size = os.path.getsize(self.log_path) |
| 31 | if size == self._last_position: |
| 32 | self.__re_find['current'] += 1 |
| 33 | return list() # return empty list if nothing has changed |
| 34 | elif size < self._last_position: |
| 35 | self._last_position = 0 # read from beginning if file has shrunk |
| 36 | |
| 37 | with open(self.log_path, **self.__open_args) as fp: |
| 38 | fp.seek(self._last_position) |
| 39 | for line in fp: |
| 40 | lines.append(line) |
| 41 | self._last_position = fp.tell() |
| 42 | self.__re_find['current'] = 0 |
| 43 | except (OSError, IOError) as error: |
| 44 | self.__re_find['current'] += 1 |
| 45 | self.error(str(error)) |
| 46 | |
| 47 | return lines or None |
| 48 | |
| 49 | def _find_recent_log_file(self): |
| 50 | """ |
| 51 | :return: |
| 52 | """ |
| 53 | self.__re_find['run'] = self.__re_find['maximum'] |
| 54 | self.__re_find['current'] = 0 |
| 55 | self.__glob_path = self.__glob_path or self.log_path # workaround for modules w/o config files |
| 56 | path_list = glob(self.__glob_path) |
| 57 | if path_list: |
| 58 | self.log_path = max(path_list) |
| 59 | return True |
| 60 | return False |
| 61 | |
| 62 | def check(self): |
| 63 | """ |
| 64 | Parse basic configuration and check if log file exists |
| 65 | :return: boolean |
| 66 | """ |
| 67 | if not self.log_path: |
| 68 | self.error('No path to log specified') |
| 69 | return None |
| 70 | |
| 71 | if self._find_recent_log_file() and os.access(self.log_path, os.R_OK) and os.path.isfile(self.log_path): |
| 72 | return True |
| 73 | self.error('Cannot access {0}'.format(self.log_path)) |
| 74 | return False |
| 75 | |
| 76 | def create(self): |
| 77 | # set cursor at last byte of log file |
| 78 | self._last_position = os.path.getsize(self.log_path) |
| 79 | status = SimpleService.create(self) |
| 80 | return status |