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我在linux上使用scrapy 0.16.2版本。我在跑:

scrapy crawl mycrawlspider -s JOBDIR=/mnt/mycrawlspider

我收到这个阻止scrapy的错误(挂起并且不会自动完成,只有^C会停止它)

2012-11-20 15:04:51+0000 [-] Unhandled Error    Traceback (most recent call last):    File "/usr/lib/python2.7/site-packages/scrapy/commands/crawl.py", line 45, in run
        self.crawler.start()      File "/usr/lib/python2.7/site-packages/scrapy/crawler.py", line 80, in start
        reactor.run(installSignalHandlers=False) # blocking call      File "/usr/lib/python2.7/site-packages/twisted/internet/base.py", line 1169, in run
        self.mainLoop()       File "/usr/lib/python2.7/site-packages/twisted/internet/base.py", line 1178, in mainLoop
        self.runUntilCurrent()  --- <exception caught here> ---       File "/usr/lib/python2.7/site-packages/twisted/internet/base.py", line 800, in runUntilCurrent
        call.func(*call.args, **call.kw)      File "/usr/lib/python2.7/site-packages/scrapy/utils/reactor.py", line 41, in __call__
        return self._func(*self._a, **self._kw)       File "/usr/lib/python2.7/site-packages/scrapy/core/engine.py", line 116, in
_next_request
        self.crawl(request, spider)       File "/usr/lib/python2.7/site-packages/scrapy/core/engine.py", line 172, in crawl
        self.schedule(request, spider)    File "/usr/lib/python2.7/site-packages/scrapy/core/engine.py", line 176, in schedule
        return self.slots[spider].scheduler.enqueue_request(request)      File "/usr/lib/python2.7/site-packages/scrapy/core/scheduler.py", line 48, in enqueue_request
        if not request.dont_filter and self.df.request_seen(request):   exceptions.AttributeError: 'NoneType' object has no attribute 'dont_filter'

顺便说一句,这在 0.14 版中有效

这是代码:

class MySpider(CrawlSpider):
    name = 'alrroya'

    NEW_IGNORED_EXTENSIONS = list(IGNORED_EXTENSIONS)
    NEW_IGNORED_EXTENSIONS.remove('pdf')

    download_delay = 0.05
    # Stay within these domains when crawling
    allowed_domains = []

    all_domains = {}

    start_urls = []

    # Add our callback which will be called for every found link
    rules = [
        Rule(SgmlLinkExtractor(deny_extensions=NEW_IGNORED_EXTENSIONS, tags=('a', 'area', 'frame', 'iframe'), attrs=('href', 'src')), follow=True, callback='parse_crawled_page')
    ]

    # How many pages crawled
    crawl_count = 0

    # How many PDFs we have found
    pdf_count = 0

    def __init__(self, *args, **kwargs):
        CrawlSpider.__init__(self, *args, **kwargs)
        dispatcher.connect(self._spider_closed, signals.spider_closed)
        dispatcher.connect(self._spider_opened, signals.spider_opened) 
        self.load_allowed_domains_and_start_urls()

    def allowed_to_start(self):
        curr_date = datetime.today()
        curr_date = datetime(curr_date.year, curr_date.month, curr_date.day)
        jobdir = self.settings['JOBDIR']
        if jobdir:
            mnt = os.path.dirname(os.path.normpath(jobdir))
        else:
            mnt = ''

        checkfile = os.path.join(mnt, '%s.crawlercheck' % self.__class__.name)
        day = timedelta(days=1)
        if os.path.exists(checkfile):
            f = open(checkfile, 'r')
            data = f.read()
            f.close()
            data = data.split('\n')
            reason = data[0]
            try:
                reason_date = datetime.strptime(data[1], '%Y-%m-%d')

            except Exception as ex:
                reason_date = None

            if reason_date and 'shutdown' in reason:
                reason = True

            else:
                if reason_date and reason_date + day <= curr_date and 'finished' in reason:
                    reason = True

                else:
                    reason = False
        else:
            reason = True

        return reason

    def _spider_opened(self, spider):
        if spider is not self:
            return

        curr_date = datetime.today()
        curr_date = datetime(curr_date.year, curr_date.month, curr_date.day)
        jobdir = spider.settings['JOBDIR']
        if jobdir:
            mnt = os.path.dirname(os.path.normpath(jobdir))
        else:
            mnt = ''

        checkfile = os.path.join(mnt, '%s.crawlercheck' % self.__class__.name)
        day = timedelta(days=1)
        if os.path.exists(checkfile):
            f = open(checkfile, 'r')
            data = f.read()
            f.close()
            data = data.split('\n')
            reason = data[0]
            try:
                reason_date = datetime.strptime(data[1], '%Y-%m-%d')

            except Exception as ex:
                reason_date = None

            if reason_date and 'shutdown' in reason:
                f = open(checkfile, 'w')
                f.write('started\n')
                f.write(str(date.today()))
                f.close()

            else:
                if reason_date and reason_date + day <= curr_date and 'finished' in reason:
                    f = open(checkfile, 'w')
                    f.write('started\n')
                    f.write(str(date.today()))
                    f.close()

                else:
                    crawler.engine.close_spider(self, 'finished')
                    if jobdir and os.path.exists(jobdir):
                        shutil.rmtree(jobdir)
                        f = open(checkfile, 'w')
                        f.write('finished\n')
                        f.write(str(date.today()))
                        f.close()
                    os._exit(1)
        else:
            f = open(checkfile, 'w')
            f.write('started\n')
            f.write(str(date.today()))
            f.close()

    def _spider_closed(self, spider, reason):
        if spider is not self:
            return

        jobdir = spider.settings['JOBDIR']
        if jobdir:
            mnt = os.path.dirname(os.path.normpath(jobdir))
        else:
            mnt = ''

        checkfile = os.path.join(mnt, '%s.crawlercheck' % self.__class__.name) 
        if 'shutdown' in reason:
            f = open(checkfile, 'w')
            f.write('shutdown\n')
            f.write(str(date.today()))
            f.close()
        else:
            if jobdir and os.path.exists(jobdir):
                shutil.rmtree(jobdir)
                f = open(checkfile, 'w')
                f.write('finished\n')
                f.write(str(date.today()))
                f.close()

    def _requests_to_follow(self, response):
        if getattr(response, 'encoding', None) != None:
            return CrawlSpider._requests_to_follow(self, response)
        else:
            return []

    def make_requests_from_url(self, url):
        http_client = httplib2.Http()
        try:
            headers = {
                'content-type': 'text/html',
                'user-agent': random.choice(USER_AGENT_LIST)
            }
            response, content = http_client.request(url, method='HEAD', headers=headers)
            #~ if 'pdf' in response['content-type'].lower() or (url.endswith('.pdf') and 'octet-stream' in response['content-type'].lower()):
            if 'pdf' in response['content-type'].lower() or 'octet-stream' in response['content-type'].lower(): 
                if self.allowed_to_start():
                    self.get_pdf_link(url)

            else:
                return CrawlSpider.make_requests_from_url(self, url)

        except Exception as ex:
            return CrawlSpider.make_requests_from_url(self, url)

    def get_pdf_link(self, url):
        source = self.__class__.name
        parsed_url = urlparse(url)
        url_domain = parsed_url.netloc
        url_path = parsed_url.path
        if url_domain:
            for domain, paths in self.__class__.all_domains[source]['allow_domains'].iteritems():
                if url_domain.endswith(domain):
                    pre_and = False
                    pre_or = False
                    and_cond = True
                    or_cond = False
                    for path in paths:
                        if path[0:1] == '!':
                            pre_and = True
                            if path[1:] not in url_path:
                                and_cond = and_cond and True
                            else:
                                and_cond = and_cond and False

                        else:
                            pre_or = True
                            if path in url_path:
                                or_cond = or_cond or True
                            else:
                                or_cond = or_cond or False

                    if pre_and and pre_or:
                        if and_cond and or_cond:
                            self.pdf_process(source, url)
                            return
                    elif pre_and:
                        if and_cond:
                            self.pdf_process(source, url)
                            return
                    elif pre_or:
                        if or_cond:
                            self.pdf_process(source, url)
                            return
                    else:
                        self.pdf_process(source, url)
                        return

    def parse_crawled_page(self, response):
        self.__class__.crawl_count += 1
        crawl_count = self.__class__.crawl_count
        if crawl_count % 100 == 0:
            print 'Crawled %d pages' % crawl_count

        if 'pdf' in response.headers.get('content-type', '').lower():
            self.get_pdf_link(response.url)

        return Item()

    def load_allowed_domains_and_start_urls(self):
        day = timedelta(days=1)
        currdate = date.today()

        alrroya = ('http://epaper.alrroya.com/currentissues.php?editiondt=' + currdate.strftime('%Y/%m/%d'),)

        self.__class__.all_domains = {
            'alrroya': {
                'start_urls': alrroya,
                'allow_domains': {
                    'epaper.alrroya.com': frozenset(()),
                }
            }
        }

        for domain in self.__class__.all_domains[self.__class__.name]['allow_domains']:
            self.__class__.allowed_domains.append(domain)

        self.__class__.start_urls.extend(self.__class__.all_domains[self.__class__.name]['start_urls'])

    def pdf_process(self, source, url):
        print '!!! ' + source + ' ' + url
4

1 回答 1

3

这似乎是 Scrapy 中的一个错误。当前版本似乎不接受从 make_requests_from_url() 返回的列表。我能够通过以下方式修改 Scrapy 代码来解决该问题。

在文件 Scrapy-0.16.5-py2.7.egg/scrapy/spider.py

改变:

def start_requests(self):
    for url in self.start_urls:
        yield self.make_requests_from_url(url)

到:

def start_requests(self):
    for url in self.start_urls:
        requests = self.make_requests_from_url(url)
        if type(requests) is list:
            for request in requests:
                yield request
        else:
            yield requests

我希望官方的 Scrapy 人员最终会解决这个问题。

于 2013-06-28T20:59:53.770 回答