Source code for airflow.contrib.hooks.aws_logs_hook

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"""
This module contains a hook (AwsLogsHook) with some very basic
functionality for interacting with AWS CloudWatch.
"""

from airflow.contrib.hooks.aws_hook import AwsHook


[docs]class AwsLogsHook(AwsHook): """ Interact with AWS CloudWatch Logs :param region_name: AWS Region Name (example: us-west-2) :type region_name: str """ def __init__(self, region_name=None, *args, **kwargs): self.region_name = region_name super(AwsLogsHook, self).__init__(*args, **kwargs)
[docs] def get_conn(self): """ Establish an AWS connection for retrieving logs. :rtype: CloudWatchLogs.Client """ return self.get_client_type('logs', region_name=self.region_name)
[docs] def get_log_events(self, log_group, log_stream_name, start_time=0, skip=0, start_from_head=True): """ A generator for log items in a single stream. This will yield all the items that are available at the current moment. :param log_group: The name of the log group. :type log_group: str :param log_stream_name: The name of the specific stream. :type log_stream_name: str :param start_time: The time stamp value to start reading the logs from (default: 0). :type start_time: int :param skip: The number of log entries to skip at the start (default: 0). This is for when there are multiple entries at the same timestamp. :type skip: int :param start_from_head: whether to start from the beginning (True) of the log or at the end of the log (False). :type start_from_head: bool :rtype: dict :return: | A CloudWatch log event with the following key-value pairs: | 'timestamp' (int): The time in milliseconds of the event. | 'message' (str): The log event data. | 'ingestionTime' (int): The time in milliseconds the event was ingested. """ next_token = None event_count = 1 while event_count > 0: if next_token is not None: token_arg = {'nextToken': next_token} else: token_arg = {} response = self.get_conn().get_log_events(logGroupName=log_group, logStreamName=log_stream_name, startTime=start_time, startFromHead=start_from_head, **token_arg) events = response['events'] event_count = len(events) if event_count > skip: events = events[skip:] skip = 0 else: skip = skip - event_count events = [] for ev in events: yield ev if 'nextForwardToken' in response: next_token = response['nextForwardToken'] else: return