AntNest

简明飞快的异步爬虫框架（python3.6+），只有600行左右的代码

功能

开箱即用的HTTP客户端提供Item extractor, 可以明确地声明如何从response解析数据(支持xpath, jpath or regex)通过 "ensure_future" and "as_completed" api 提供方便的工作流

安装

pip install ant_nest

使用方式：

创建一个Demo项目:

>>> ant_nest -c examples

自动会创建以下文件：

drwxr-xr-x 5 bruce staff 160 Jun 30 18:24 ants-rw-r--r-- 1 bruce staff 208 Jun 26 22:59 settings.py

假设我们想获取GitHub热门仓库，让我们创建一个"examples/ants/example2.py":

from ant_nest import *from yarl import URLclass GithubAnt(Ant): """Crawl trending repositories from github""" item_pipelines = [ ItemFieldReplacePipeline( ('meta_content', 'star', 'fork'), excess_chars=('\r', '\n', '\t', ' ')) ] concurrent_limit = 1 # save the website`s and your bandwidth! def __init__(self): super().__init__() self.item_extractor = ItemExtractor(dict) self.item_extractor.add_pattern( 'xpath', 'title', '//h1/strong/a/text()') self.item_extractor.add_pattern( 'xpath', 'author', '//h1/span/a/text()', default='Not found') self.item_extractor.add_pattern( 'xpath', 'meta_content', '//div[@class="repository-meta-content col-11 mb-1"]//text()', extract_type=ItemExtractor.EXTRACT_WITH_JOIN_ALL) self.item_extractor.add_pattern( 'xpath', 'star', '//a[@class="social-count js-social-count"]/text()') self.item_extractor.add_pattern( 'xpath', 'fork', '//a[@class="social-count"]/text()') async def crawl_repo(self, url): """Crawl information from one repo""" response = await self.request(url) # extract item from response item = self.item_extractor.extract(response) item['origin_url'] = response.url await self.collect(item) # let item go through pipelines(be cleaned) self.logger.info('*' * 70 + 'I got one hot repo!\n' + str(item)) async def run(self): """App entrance, our play ground""" response = await self.request('') for url in response.html_element.xpath( '/html/body/div[4]/div[2]/div/div[2]/div[1]/article//h1/a[2]/' '@href'): # crawl many repos with our coroutines pool self.schedule_coroutine( self.crawl_repo(response.url.join(URL(url)))) self.logger.info('Waiting...')

然后我们可以列出所有可运行的爬虫(在"examples"文件夹下)

>>> $ant_nest -lants.example2.GithubAnt

运行! (without debug log):

>>> ant_nest -a ants.example2.GithubAntINFO:GithubAnt:OpeningINFO:GithubAnt:Waiting...INFO:GithubAnt:**********************************************************************I got one hot repo!{'title': 'NLP-progress', 'author': 'sebastianruder', 'meta_content': 'Repository to track the progress in Natural Language Processing (NLP), including the datasets and the current state-of-the-art for the most common NLP tasks.', 'star': '3,743', 'fork': '327', 'origin_url': URL('')}INFO:GithubAnt:**********************************************************************I got one hot repo!{'title': 'material-dashboard', 'author': 'creativetimofficial', 'meta_content': 'Material Dashboard - Open Source Bootstrap 4 Material Design Admin…', 'star': '6,032', 'fork': '187', 'origin_url': URL('')}INFO:GithubAnt:**********************************************************************I got one hot repo!{'title': 'mkcert', 'author': 'FiloSottile', 'meta_content': "A simple zero-config tool to make locally-trusted development certificates with any names you'd like.", 'star': '2,311', 'fork': '60', 'origin_url': URL('')}INFO:GithubAnt:**********************************************************************I got one hot repo!{'title': 'pure-bash-bible', 'author': 'dylanaraps', 'meta_content': ' A collection of pure bash alternatives to external processes.', 'star': '6,385', 'fork': '210', 'origin_url': URL('')}INFO:GithubAnt:**********************************************************************I got one hot repo!{'title': 'flutter', 'author': 'flutter', 'meta_content': 'Flutter makes it easy and fast to build beautiful mobile apps.', 'star': '30,579', 'fork': '1,337', 'origin_url': URL('')}INFO:GithubAnt:**********************************************************************I got one hot repo!{'title': 'Java-Interview', 'author': 'crossoverJie', 'meta_content': '\u200d Java related : basic, concurrent, algorithm …', 'star': '4,687', 'fork': '409', 'origin_url': URL('')}INFO:GithubAnt:ClosedINFO:GithubAnt:Get 7 Request in totalINFO:GithubAnt:Get 7 Response in totalINFO:GithubAnt:Get 6 dict in totalINFO:GithubAnt:Run GithubAnt in 18.157656 seconds

我们可以通过类属性来配置我们的爬虫

class Ant(abc.ABC): response_pipelines: List[Pipeline] = [] request_pipelines: List[Pipeline] = [] item_pipelines: List[Pipeline] = [] request_cls = Request response_cls = Response request_timeout = DEFAULT_TIMEOUT.total request_retries = 3 request_retry_delay = 5 request_proxies: List[Union[str, URL]] = [] request_max_redirects = 10 request_allow_redirects = True response_in_stream = False connection_limit = 100 # see "TCPConnector" in "aiohttp" connection_limit_per_host = 0 concurrent_limit = 100