Scrapy-Redis-BloomFilter
This is a package for supporting BloomFilter of Scrapy-Redis.
Installation
You can easily install this package with pip:
pip install scrapy-redis-bloomfilter
Dependency:
- Scrapy-Redis >= 0.6.8
Usage
Add this settings to settings.py:
# Use this Scheduler, if your scrapy_redis version is <= 0.7.1
SCHEDULER = "scrapy_redis_bloomfilter.scheduler.Scheduler"
# Ensure all spiders share same duplicates filter through redis
DUPEFILTER_CLASS = "scrapy_redis_bloomfilter.dupefilter.RFPDupeFilter"
# Redis URL
REDIS_URL = 'redis://localhost:6379'
# Number of Hash Functions to use, defaults to 6
BLOOMFILTER_HASH_NUMBER = 6
# Redis Memory Bit of Bloom Filter Usage, 30 means 2^30 = 128MB, defaults to 30
BLOOMFILTER_BIT = 10
# Persist
SCHEDULER_PERSIST = TrueTest
Here is a test of this project, usage:
git clone https://github.com/Python3WebSpider/ScrapyRedisBloomFilter.git
cd ScrapyRedisBloomFilter/test
scrapy crawl test
Note: please change REDIS_URL in settings.py.
Spider like this:
from scrapy import Request, Spider
class TestSpider(Spider):
name = 'test'
base_url = 'https://www.baidu.com/s?wd='
def start_requests(self):
for i in range(10):
url = self.base_url + str(i)
yield Request(url, callback=self.parse)
# Here contains 10 duplicated Requests
for i in range(100):
url = self.base_url + str(i)
yield Request(url, callback=self.parse)
def parse(self, response):
self.logger.debug('Response of ' + response.url)Result like this:
{'bloomfilter/filtered': 10, # This is the number of Request filtered by BloomFilter
'downloader/request_bytes': 34021,
'downloader/request_count': 100,
'downloader/request_method_count/GET': 100,
'downloader/response_bytes': 72943,
'downloader/response_count': 100,
'downloader/response_status_count/200': 100,
'finish_reason': 'finished',
'finish_time': datetime.datetime(2017, 8, 11, 9, 34, 30, 419597),
'log_count/DEBUG': 202,
'log_count/INFO': 7,
'memusage/max': 54153216,
'memusage/startup': 54153216,
'response_received_count': 100,
'scheduler/dequeued/redis': 100,
'scheduler/enqueued/redis': 100,
'start_time': datetime.datetime(2017, 8, 11, 9, 34, 26, 495018)}