| # |
| # Licensed to the Apache Software Foundation (ASF) under one or more |
| # contributor license agreements. See the NOTICE file distributed with |
| # this work for additional information regarding copyright ownership. |
| # The ASF licenses this file to You under the Apache License, Version 2.0 |
| # (the "License"); you may not use this file except in compliance with |
| # the License. You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| # |
| |
| ''' |
| Methods that will be used to process and prepare dns data, before being sent to |
| Kafka cluster. |
| ''' |
| |
| import logging |
| import re |
| import sys |
| import tempfile |
| |
| from common.utils import Util |
| from datetime import datetime |
| |
| COMMAND = 'tshark -r {0} {1} > {2}' |
| EPOCH = datetime(1970, 1, 1) |
| |
| def convert(pcap, tmpdir, opts='', prefix=None): |
| ''' |
| Convert `pcap` file to a comma-separated output format. |
| |
| :param pcap : Path of binary file. |
| :param tmpdir : Path of local staging area. |
| :param opts : A set of options for `tshark` command. |
| :param prefix : If `prefix` is specified, the file name will begin with that; |
| otherwise, a default `prefix` is used. |
| :returns : Path of CSV-converted file. |
| :rtype : ``str`` |
| :raises OSError: If an error occurs while executing the `tshark` command. |
| ''' |
| logger = logging.getLogger('SPOT.INGEST.DNS.PROCESS') |
| |
| with tempfile.NamedTemporaryFile(prefix=prefix, dir=tmpdir, delete=False) as fp: |
| command = COMMAND.format(pcap, opts, fp.name) |
| |
| logger.debug('Execute command: {0}'.format(command)) |
| Util.popen(command, raises=True) |
| |
| return fp.name |
| |
| def prepare(csvfile, max_req_size): |
| ''' |
| Prepare text-formatted data for transmission through the Kafka cluster. |
| |
| This method takes a CSV file and groups it into segments, according to the |
| pattern '%Y%m%d%h'. If the size of each segment is greater than the maximum size |
| of a request, then divides each segment into smaller ones so that they can be |
| transmitted. |
| |
| :param csvfile : Path of CSV-converted file; result of `convert` method. |
| :param max_req_size: The maximum size of a request. |
| :returns : A generator which yields the timestamp (in milliseconds) and a |
| list of lines from the CSV-converted file. |
| :rtype : :class:`types.GeneratorType` |
| :raises IOError : If the given file has no any valid line. |
| ''' |
| msg_list = [] |
| msg_size = segmentid = 0 |
| logger = logging.getLogger('SPOT.INGEST.DNS.PROCESS') |
| partition = timestamp = None |
| pattern = re.compile('[0-9]{10}.[0-9]{9}') |
| |
| with open(csvfile, 'r') as fp: |
| for line in fp: |
| value = line.strip() |
| if not value: continue |
| |
| match = pattern.search(value.split(',')[2]) |
| if not match: continue |
| |
| size = sys.getsizeof(value) |
| # .........................assume the first 15 characters of the line, as |
| # the `partition` - and not the result of `search` - e.g. 'Sep 8, 2017 11' |
| if value[:15] == partition and (msg_size + size) < max_req_size: |
| msg_list.append(value) |
| msg_size += size |
| continue |
| |
| # .........................if the hour is different or the message size is |
| # above the maximum, then yield existing list and continue with an empty one |
| if timestamp: |
| logger.debug('Yield segment-{0}: {1} lines, {2} bytes'.format(segmentid, |
| len(msg_list), msg_size)) |
| segmentid += 1 |
| |
| yield (int(timestamp.total_seconds() * 1000), msg_list) |
| |
| msg_list = [value] |
| msg_size = size |
| partition = value[:15] |
| timestamp = datetime.fromtimestamp(float(match.group())) - EPOCH |
| |
| # .................................send the last lines from the file. The check of |
| # `timestamp` is in case the file is empty and `timestamp` is still ``None``. |
| if not timestamp: |
| raise IOError('CSV-converted file has no valid lines.') |
| |
| logger.debug('Yield segment-{0}: {1} lines, {2} bytes'.format(segmentid, |
| len(msg_list), msg_size)) |
| |
| yield (int(timestamp.total_seconds() * 1000), msg_list) |