Joe*_* Wu 39 python report scrapy web-scraping
我是scrapy的新手,它是我知道的惊人的爬虫框架!
在我的项目中,我发送了超过90,000个请求,但其中一些请求失败了.我将日志级别设置为INFO,我只能看到一些统计信息,但没有详细信息.
2012-12-05 21:03:04+0800 [pd_spider] INFO: Dumping spider stats:
{'downloader/exception_count': 1,
'downloader/exception_type_count/twisted.internet.error.ConnectionDone': 1,
'downloader/request_bytes': 46282582,
'downloader/request_count': 92383,
'downloader/request_method_count/GET': 92383,
'downloader/response_bytes': 123766459,
'downloader/response_count': 92382,
'downloader/response_status_count/200': 92382,
'finish_reason': 'finished',
'finish_time': datetime.datetime(2012, 12, 5, 13, 3, 4, 836000),
'item_scraped_count': 46191,
'request_depth_max': 1,
'scheduler/memory_enqueued': 92383,
'start_time': datetime.datetime(2012, 12, 5, 12, 23, 25, 427000)}
有没有办法获得更多细节报告？例如,显示那些失败的URL.谢谢!
Tal*_*lin 49
是的,这是可能的.
我在我的蜘蛛类中添加了一个failed_urls列表,并且如果响应的状态为404,则会向其添加url(这将需要扩展以涵盖其他错误状态).
然后我添加了一个把列表连接成一个字符串的句柄,并在蜘蛛关闭时将其添加到统计数据中.
根据您的评论,可以跟踪扭曲的错误.
from scrapy.spider import BaseSpider
from scrapy.xlib.pydispatch import dispatcher
from scrapy import signals
class MySpider(BaseSpider):
handle_httpstatus_list = [404]
name = "myspider"
allowed_domains = ["example.com"]
start_urls = [
'http://www.example.com/thisurlexists.html',
'http://www.example.com/thisurldoesnotexist.html',
'http://www.example.com/neitherdoesthisone.html'
]
def __init__(self, category=None):
self.failed_urls = []
def parse(self, response):
if response.status == 404:
self.crawler.stats.inc_value('failed_url_count')
self.failed_urls.append(response.url)
def handle_spider_closed(spider, reason):
self.crawler.stats.set_value('failed_urls', ','.join(spider.failed_urls))
def process_exception(self, response, exception, spider):
ex_class = "%s.%s" % (exception.__class__.__module__, exception.__class__.__name__)
self.crawler.stats.inc_value('downloader/exception_count', spider=spider)
self.crawler.stats.inc_value('downloader/exception_type_count/%s' % ex_class, spider=spider)
dispatcher.connect(handle_spider_closed, signals.spider_closed)
输出(下载器/ exception_count*统计信息仅在实际抛出异常时出现 - 我通过在关闭无线适配器后尝试运行蜘蛛来模拟它们):
2012-12-10 11:15:26+0000 [myspider] INFO: Dumping Scrapy stats:
{'downloader/exception_count': 15,
'downloader/exception_type_count/twisted.internet.error.DNSLookupError': 15,
'downloader/request_bytes': 717,
'downloader/request_count': 3,
'downloader/request_method_count/GET': 3,
'downloader/response_bytes': 15209,
'downloader/response_count': 3,
'downloader/response_status_count/200': 1,
'downloader/response_status_count/404': 2,
'failed_url_count': 2,
'failed_urls': 'http://www.example.com/thisurldoesnotexist.html, http://www.example.com/neitherdoesthisone.html'
'finish_reason': 'finished',
'finish_time': datetime.datetime(2012, 12, 10, 11, 15, 26, 874000),
'log_count/DEBUG': 9,
'log_count/ERROR': 2,
'log_count/INFO': 4,
'response_received_count': 3,
'scheduler/dequeued': 3,
'scheduler/dequeued/memory': 3,
'scheduler/enqueued': 3,
'scheduler/enqueued/memory': 3,
'spider_exceptions/NameError': 2,
'start_time': datetime.datetime(2012, 12, 10, 11, 15, 26, 560000)}
ale*_*cxe 15
这是另一个如何处理和收集404错误的例子(检查github帮助页面):
from scrapy.selector import HtmlXPathSelector
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.item import Item, Field
class GitHubLinkItem(Item):
url = Field()
referer = Field()
status = Field()
class GithubHelpSpider(CrawlSpider):
name = "github_help"
allowed_domains = ["help.github.com"]
start_urls = ["https://help.github.com", ]
handle_httpstatus_list = [404]
rules = (Rule(SgmlLinkExtractor(), callback='parse_item', follow=True),)
def parse_item(self, response):
if response.status == 404:
item = GitHubLinkItem()
item['url'] = response.url
item['referer'] = response.request.headers.get('Referer')
item['status'] = response.status
return item
只要运行scrapy runspider与-o output.json和看到的项目的列表output.json文件.
msc*_*arf 13
来自@Talvalin和@alecxe的答案对我有很大帮助,但它们似乎没有捕获不生成响应对象的下载事件(例如,twisted.internet.error.TimeoutError和twisted.web.http.PotentialDataLoss).这些错误在运行结束时显示在stats转储中,但没有任何元信息.
正如我在这里发现的那样,stats.py中间件跟踪错误,在DownloaderStats类' process_exception方法中捕获,特别是在ex_class变量中,根据需要递增每个错误类型,然后在运行结束时转储计数.
要将此类错误与来自相应请求对象的信息进行匹配,您可以为每个请求添加唯一ID(via request.meta),然后将其拉入以下process_exception方法stats.py:
self.stats.set_value('downloader/my_errs/{0}'.format(request.meta), ex_class)
这将为每个基于下载程序的错误生成唯一的字符串,而不会附带响应.然后,您可以将更改保存stats.py为其他内容(例如my_stats.py),将其添加到下载器中间件(具有正确的优先级),并禁用该库存stats.py:
DOWNLOADER_MIDDLEWARES = {
'myproject.my_stats.MyDownloaderStats': 850,
'scrapy.downloadermiddleware.stats.DownloaderStats': None,
}
在运行结束时的输出如下所示(这里使用,其中每个请求URL映射到一个GROUP_ID和member_id由斜线分开,像元信息'0/14'):
{'downloader/exception_count': 3,
'downloader/exception_type_count/twisted.web.http.PotentialDataLoss': 3,
'downloader/my_errs/0/1': 'twisted.web.http.PotentialDataLoss',
'downloader/my_errs/0/38': 'twisted.web.http.PotentialDataLoss',
'downloader/my_errs/0/86': 'twisted.web.http.PotentialDataLoss',
'downloader/request_bytes': 47583,
'downloader/request_count': 133,
'downloader/request_method_count/GET': 133,
'downloader/response_bytes': 3416996,
'downloader/response_count': 130,
'downloader/response_status_count/200': 95,
'downloader/response_status_count/301': 24,
'downloader/response_status_count/302': 8,
'downloader/response_status_count/500': 3,
'finish_reason': 'finished'....}
此答案处理非基于下载程序的错误.
Pyt*_*uru 11
Scrapy默认忽略404并且不解析.要处理404错误,请执行此操作.这很容易,如果你得到错误代码404作为响应,你可以用非常简单的方式处理这个......在设置写入
HTTPERROR_ALLOWED_CODES = [404,403]
然后在您的解析函数中处理响应状态代码.
def parse(self,response):
if response.status == 404:
#your action on error
在设置中并在解析函数中获得响应
作为scrapy 0.24.6中,所建议的方法alecxe不会赶上与起始网址错误.要记录您需要覆盖的起始URL的错误parse_start_urls.为此目的调整alexce的答案,你会得到:
from scrapy.selector import HtmlXPathSelector
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.item import Item, Field
class GitHubLinkItem(Item):
url = Field()
referer = Field()
status = Field()
class GithubHelpSpider(CrawlSpider):
name = "github_help"
allowed_domains = ["help.github.com"]
start_urls = ["https://help.github.com", ]
handle_httpstatus_list = [404]
rules = (Rule(SgmlLinkExtractor(), callback='parse_item', follow=True),)
def parse_start_url(self, response):
return self.handle_response(response)
def parse_item(self, response):
return self.handle_response(response)
def handle_response(self, response):
if response.status == 404:
item = GitHubLinkItem()
item['url'] = response.url
item['referer'] = response.request.headers.get('Referer')
item['status'] = response.status
return item
小智 5
这是这个问题的更新.我遇到了类似的问题,需要使用scrapy信号来调用我的管道中的函数.我已经编辑了@ Talvalin的代码,但是为了更清晰一点,我想回答一下.
基本上,您应该将self添加为handle_spider_closed的参数.您还应该在init中调用调度程序,以便可以将spider实例(self)传递给handleing方法.
from scrapy.spider import Spider
from scrapy.xlib.pydispatch import dispatcher
from scrapy import signals
class MySpider(Spider):
handle_httpstatus_list = [404]
name = "myspider"
allowed_domains = ["example.com"]
start_urls = [
'http://www.example.com/thisurlexists.html',
'http://www.example.com/thisurldoesnotexist.html',
'http://www.example.com/neitherdoesthisone.html'
]
def __init__(self, category=None):
self.failed_urls = []
# the dispatcher is now called in init
dispatcher.connect(self.handle_spider_closed,signals.spider_closed)
def parse(self, response):
if response.status == 404:
self.crawler.stats.inc_value('failed_url_count')
self.failed_urls.append(response.url)
def handle_spider_closed(self, spider, reason): # added self
self.crawler.stats.set_value('failed_urls',','.join(spider.failed_urls))
def process_exception(self, response, exception, spider):
ex_class = "%s.%s" % (exception.__class__.__module__, exception.__class__.__name__)
self.crawler.stats.inc_value('downloader/exception_count', spider=spider)
self.crawler.stats.inc_value('downloader/exception_type_count/%s' % ex_class, spider=spider)
我希望这有助于将来遇到同样问题的任何人.