예제 #1
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    def _run_extraction(self, name, templates, page, descriptor, expected_output):
        self.trace = None
        template_pages = [HtmlPage(None, {}, t) for t in templates]
        # extracts with trace enabled in order to generate traceback
        extractor = InstanceBasedLearningExtractor([(t, descriptor) for t in template_pages], True)
        actual_output, _ = extractor.extract(HtmlPage(None, {}, page))
        if actual_output is not None:
            actual_output = actual_output[0]
            self.trace = ["Extractor:\n%s" % extractor] + actual_output.pop('trace')
        # extracts again with trace disabled in order to get the pure output
        extractor = InstanceBasedLearningExtractor([(t, descriptor) for t in template_pages])
        actual_output, _ = extractor.extract(HtmlPage(None, {}, page))
        if actual_output is None:
            if expected_output is None:
                return
            assert False, "failed to extract data for test '%s'" % name
        else:
            actual_output = actual_output[0]
        expected_names = set(expected_output.keys())
        actual_names = set(actual_output.keys())
        
        missing_in_output = filter(None, expected_names - actual_names)
        error = "attributes '%s' were expected but were not present in test '%s'" % \
                ("', '".join(missing_in_output), name)
        assert len(missing_in_output) == 0, error

        unexpected = actual_names - expected_names
        error = "unexpected attributes %s in test '%s'" % \
                (', '.join(unexpected), name)
        assert len(unexpected) == 0, error

        for k, v in expected_output.items():
            extracted = actual_output[k]
            assert v == extracted, "in test '%s' for attribute '%s', " \
                "expected value '%s' but got '%s'" % (name, k, v, extracted)
예제 #2
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파일: spider.py 프로젝트: ra2003/slybot
    def __init__(self, name, spec, item_schemas, all_extractors, **kw):
        super(IblSpider, self).__init__(name, **kw)
        spec = deepcopy(spec)
        for key, val in kw.items():
            if isinstance(val, basestring) and key in ['start_urls', 'exclude_patterns', 'follow_patterns', 'allowed_domains']:
                val = val.splitlines()
            spec[key] = val

        self._item_template_pages = sorted((
            [t['scrapes'], dict_to_page(t, 'annotated_body'),
            t.get('extractors', [])] \
            for t in spec['templates'] if t.get('page_type', 'item') == 'item'
        ), key=lambda pair: pair[0])

        # generate ibl extractor for links pages
        _links_pages = [dict_to_page(t, 'annotated_body')
                for t in spec['templates'] if t.get('page_type') == 'links']
        _links_item_descriptor = create_slybot_item_descriptor({'fields': {}})
        self._links_ibl_extractor = InstanceBasedLearningExtractor([(t, _links_item_descriptor) for t in _links_pages]) \
                if _links_pages else None

        self._ipages = [page for _, page, _ in self._item_template_pages]

        self.html_link_extractor = HtmlLinkExtractor()
        self.rss_link_extractor = RssLinkExtractor()
        self.build_url_filter(spec)

        self.itemcls_info = {}
        for itemclass_name, triplets in itertools.groupby(self._item_template_pages, operator.itemgetter(0)):
            page_extractors_pairs = map(operator.itemgetter(1, 2), triplets)
            schema = item_schemas[itemclass_name]
            item_cls = SlybotItem.create_iblitem_class(schema)

            page_descriptor_pairs = []
            for page, template_extractors in page_extractors_pairs:
                item_descriptor = create_slybot_item_descriptor(schema)
                apply_extractors(item_descriptor, template_extractors, all_extractors)
                page_descriptor_pairs.append((page, item_descriptor))

            extractor = InstanceBasedLearningExtractor(page_descriptor_pairs)

            self.itemcls_info[itemclass_name] = {
                'class': item_cls,
                'descriptor': item_descriptor,
                'extractor': extractor,
            }

        self.login_requests = []
        self.form_requests = []
        self._start_requests = []
        self.generic_form = GenericForm(**kw)
        self._create_init_requests(spec.get("init_requests", []))
        self._process_start_urls(spec)
        self.allowed_domains = spec.get('allowed_domains',
                                        self._get_allowed_domains(self._ipages))
        if not self.allowed_domains:
            self.allowed_domains = None
예제 #3
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    def setup_bot(self, settings, spec, items, extractors):
        """
        Perform any initialization needed for crawling using this plugin
        """
        _item_template_pages = sorted(([
            t['scrapes'],
            dict_to_page(t, 'annotated_body'),
            t.get('extractors', [])
        ] for t in spec['templates'] if t.get('page_type', 'item') == 'item'),
                                      key=lambda pair: pair[0])

        self.itemcls_info = {}
        if settings.get('AUTO_PAGINATION'):
            self.html_link_extractor = PaginationExtractor()
        else:
            self.html_link_extractor = HtmlLinkExtractor()
        for itemclass_name, triplets in groupby(_item_template_pages,
                                                itemgetter(0)):
            page_extractors_pairs = map(itemgetter(1, 2), triplets)
            schema = items[itemclass_name]
            item_cls = SlybotItem.create_iblitem_class(schema)

            page_descriptor_pairs = []
            for page, template_extractors in page_extractors_pairs:
                item_descriptor = create_slybot_item_descriptor(schema)
                apply_extractors(item_descriptor, template_extractors,
                                 extractors)
                page_descriptor_pairs.append((page, item_descriptor))

            extractor = InstanceBasedLearningExtractor(page_descriptor_pairs)

            self.itemcls_info[itemclass_name] = {
                'class': item_cls,
                'descriptor': item_descriptor,
                'extractor': extractor,
            }

        # generate ibl extractor for links pages
        _links_pages = [
            dict_to_page(t, 'annotated_body') for t in spec['templates']
            if t.get('page_type') == 'links'
        ]
        _links_item_descriptor = create_slybot_item_descriptor({'fields': {}})
        self._links_ibl_extractor = InstanceBasedLearningExtractor(
            [(t, _links_item_descriptor) for t in _links_pages]) \
            if _links_pages else None

        self.build_url_filter(spec)
예제 #4
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 def scrape_page2(self, page, fields_spec):
     if self._ex is None:
         self._ex = InstanceBasedLearningExtractor(
             ((t, get_visual_tool_item_descriptor(fields_spec))
              for t in self._templates), False, True)
     res = self._ex.extract(page)[0]
     return res
예제 #5
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    def scrape(self, url=None, html=None, encoding='utf-8'):
        ## not version from https://github.com/scrapy/scrapely/blob/master/scrapely/extraction/pageparsing.py
        ## may need to replace with version from inspect.getsourcelines(Scraper.scrape), as this version is

        page = self._get_page(url, encoding, html)
        ex = InstanceBasedLearningExtractor(self.templates)
        return ex.extract(page)[0]
예제 #6
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    def test_type_extractor(self):
        schema = {
            "fields": {
                'gender': {
                    'required': False,
                    'type': 'number',
                    'vary': False,
                }
            }
        }
        descriptor = create_slybot_item_descriptor(schema)
        extractors = {
            1: {
                "type_extractor": "text"
            },
            2: {
                "regular_expression": "Gender\\s+(Male|Female)"
            }
        }
        apply_extractors(descriptor, {"gender": [1, 2]}, extractors)

        ibl_extractor = InstanceBasedLearningExtractor([(self.template,
                                                         descriptor)])
        self.assertEqual(
            ibl_extractor.extract(self.target)[0][0], {u'gender': [u'Male']})
예제 #7
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def get_extractor(site_id):
    sds = ScraperDescriptor.objects.filter(site__id=site_id)
    if not sds.exists():
        return

    tmpls = []

    for s in sds:
        items = s.items.filter(descriptor__target__symbol='ProductInfo')
        idesc = ItemDescriptor('', '', [
            FieldDescriptor(i.descriptor.symbol,
                            i.descriptor.desc,
                            extractor=types[i.descriptor.typ.symbol](i.value))
            for i in items
        ])
        ts = load_templates(s.id)
        tmpls += [(t, idesc) for _, t in ts]
    if tmpls:
        ex = InstanceBasedLearningExtractor(tmpls)

        def extractor(response):
            page = HtmlPage(response.url,
                            headers=response.headers,
                            body=response.body.decode(response.encoding),
                            encoding=response.encoding)
            extract = ex.extract(page)
            if extract[0] is not None:
                for e in extract[0]:
                    yield e

        return extractor
예제 #8
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 def test_annotate_ignore_unpaired(self):
     tm = TemplateMaker(self.PAGE)
     tm.annotate('field1', best_match("and that's"), best_match=False)
     tpl = tm.get_template()
     ex = InstanceBasedLearningExtractor([(tpl, None)])
     self.assertEqual(ex.extract(self.PAGE)[0],
         [{u'field1': [u"More text with unpaired tag <img />and that's it"]}])
예제 #9
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 def test_annotate_multiple(self):
     tm = TemplateMaker(self.PAGE)
     tm.annotate('field1', best_match('text to annotate'), best_match=False)
     tpl = tm.get_template()
     ex = InstanceBasedLearningExtractor([(tpl, None)])
     self.assertEqual(ex.extract(self.PAGE)[0],
         [{u'field1': [u'Some text to annotate here', u'Another text to annotate there']}])
예제 #10
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    def test_extraction(self, name, templates, page, descriptor,
                        expected_output):
        template_pages = [HtmlPage(None, {}, t) for t in templates]

        extractor = InstanceBasedLearningExtractor([(t, descriptor)
                                                    for t in template_pages])
        actual_output, _ = extractor.extract(HtmlPage(None, {}, page))

        self.assertEqual(expected_output, actual_output and actual_output[0])
예제 #11
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파일: tool.py 프로젝트: wangsouc/scrapely
 def do_scrape(self, url):
     """scrape <url> - scrape url (alias: s)"""
     templates = self._load_templates()
     if assert_or_print(templates, "no templates available"):
         return
     # fall back to the template encoding if none is specified
     page = url_to_page(url, default_encoding=templates[0].encoding)
     ex = InstanceBasedLearningExtractor((t, None) for t in templates)
     pprint.pprint(ex.extract(page)[0])
예제 #12
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    def test_default_type_extractor(self):
        schema = {'fields': {}}
        descriptor = create_slybot_item_descriptor(schema)
        extractors = {1: {"regular_expression": "Gender\\s+(Male|Female)"}}
        apply_extractors(descriptor, {"gender": [1]}, extractors)

        ibl_extractor = InstanceBasedLearningExtractor([(self.template,
                                                         descriptor)])
        self.assertEqual(
            ibl_extractor.extract(self.target)[0][0], {u'gender': [u'Male']})
예제 #13
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    def test_negative_hit_w_regex(self):
        schema = {
            'fields': {
                'gender': {
                    'required': False,
                    'type': 'number',
                    'vary': False,
                }
            }
        }
        descriptor = create_slybot_item_descriptor(schema)
        extractors = {1: {"regular_expression": "Gender\\s+(Male|Female)"}}
        apply_extractors(descriptor, {"gender": [1]}, extractors)

        ibl_extractor = InstanceBasedLearningExtractor([(self.template,
                                                         descriptor)])
        self.assertEqual(ibl_extractor.extract(self.target)[0], None)
예제 #14
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    def test_text_type_w_regex_and_no_groups(self):
        schema = {
            'fields': {
                'gender': {
                    'required': False,
                    'type': 'text',
                    'vary': False,
                }
            }
        }
        descriptor = create_slybot_item_descriptor(schema)
        extractors = {1: {"regular_expression": "Gender"}}
        apply_extractors(descriptor, {"gender": [1]}, extractors)

        ibl_extractor = InstanceBasedLearningExtractor([(self.template,
                                                         descriptor)])
        self.assertEqual(
            ibl_extractor.extract(self.target)[0][0], {u'gender': [u'Gender']})
예제 #15
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    def test_raw_type_w_regex(self):
        schema = {
            'fields': {
                'gender': {
                    'required': False,
                    'type': 'raw',
                    'vary': False,
                }
            }
        }
        descriptor = create_slybot_item_descriptor(schema)
        extractors = {
            1: {
                "regular_expression": "Gender.*(<td\s*>(?:Male|Female)</td>)"
            }
        }
        apply_extractors(descriptor, {"gender": [1]}, extractors)

        ibl_extractor = InstanceBasedLearningExtractor([(self.template,
                                                         descriptor)])
        self.assertEqual(
            ibl_extractor.extract(self.target)[0][0],
            {u'gender': [u'<td >Male</td>']})
예제 #16
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    def test_extractor_w_empty_string_extraction(self):
        schema = {
            'fields': {
                'gender': {
                    'required': False,
                    'type': 'text',
                    'vary': False,
                },
                'name': {
                    'required': True,
                    'type': 'text',
                    'vary': False,
                }
            }
        }
        descriptor = create_slybot_item_descriptor(schema)
        extractors = {1: {"regular_expression": "([0-9]+)"}}
        apply_extractors(descriptor, {"gender": [1]}, extractors)

        ibl_extractor = InstanceBasedLearningExtractor([(self.template2,
                                                         descriptor)])
        self.assertEqual(
            ibl_extractor.extract(self.target2)[0][0],
            {u'name': [u'Name Olivia']})
예제 #17
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파일: scrape.py 프로젝트: I-TREND/SASF
        map(
            lambda (n, s, desc): (n, s, u'%s' %
                                  (desc.name, ), types[desc.typ.symbol]),
            ((n, s, KeyValueDescriptor.objects.get(symbol=n))
             for n, s, _, _ in items
             if KeyValueDescriptor.objects.filter(symbol=n).exists())))
    idesc = ItemDescriptor('', '', [
        FieldDescriptor(n, desc, extractor=fnc(s)) for n, s, desc, fnc in items
    ])
    ts = load_templates('scraper.json', 'site-%d' % site.id)
    if not ts:
        ts = annotate(url, 'site-%d' % site.id,
                      [(n, s) for n, s, _, _ in items])
    tmpls += [(tm, idesc) for tm in ts]

ex = InstanceBasedLearningExtractor(tmpls)

urls = (
    'http://www.rc-chem.eu/doprava',  # should fail
    'http://www.rc-chem.eu/produkty/2-fma',
    'http://www.rc-chem.eu/produkty/3-fmc',
    'http://www.rc-chem.eu/produkty/3-mmc-crystal',
    'http://www.rc-chem.eu/produkty/4-fa-crystal',
    'http://www.rc-chem.eu/produkty/dimethylone',
    'http://www.rc-chem.eu/produkty/ethylphenidate',
    'http://www.rc-chem.eu/produkty/mpa',
    'http://www.rc-chem.eu/produkty/neb',
    'http://www.rc-chem.eu/produkty/pentedrone-velky-crystal',
    'http://www.rc-chem.eu/produkty/thio-crystal',
    'http://www.rc-chem.eu/produkty/thio-velky-crystal',
    'http://mefedronprodej.webnode.cz/produkty-1/',
예제 #18
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    def setup_bot(self, settings, spec, items, extractors, logger):
        """
        Perform any initialization needed for crawling using this plugin
        """
        self.logger = logger
        templates = map(self._get_annotated_template, spec['templates'])

        _item_template_pages = sorted(([
            t.get('scrapes'),
            dict_to_page(t, 'annotated_body'),
            t.get('extractors', []),
            t.get('version', '0.12.0')
        ] for t in templates if t.get('page_type', 'item') == 'item'),
                                      key=lambda x: x[0])
        self.item_classes = {}
        self.template_scrapes = {
            template.get('page_id'): template['scrapes']
            for template in templates
        }
        if (settings.get('AUTO_PAGINATION')
                or spec.get('links_to_follow') == 'auto'):
            self.html_link_extractor = PaginationExtractor()
        else:
            self.html_link_extractor = HtmlLinkExtractor()
        for schema_name, schema in items.items():
            if schema_name not in self.item_classes:
                if not schema.get('name'):
                    schema['name'] = schema_name
                item_cls = SlybotItem.create_iblitem_class(schema)
                self.item_classes[schema_name] = item_cls

        # Create descriptors and apply additional extractors to fields
        page_descriptor_pairs = []
        self.schema_descriptors = {}
        for default, template, template_extractors, v in _item_template_pages:
            descriptors = OrderedDict()
            for schema_name, schema in items.items():
                item_descriptor = create_slybot_item_descriptor(
                    schema, schema_name)
                apply_extractors(item_descriptor, template_extractors,
                                 extractors)
                descriptors[schema_name] = item_descriptor
            descriptor = descriptors.values() or [{}]
            descriptors['#default'] = descriptors.get(default, descriptor[0])
            self.schema_descriptors[template.page_id] = descriptors['#default']
            page_descriptor_pairs.append((template, descriptors, v))
            add_extractors_to_descriptors(descriptors, extractors)

        grouped = itertools.groupby(
            sorted(page_descriptor_pairs, key=operator.itemgetter(2)),
            lambda x: x[2] < '0.13.0')
        self.extractors = []
        for version, group in grouped:
            if version:
                self.extractors.append(
                    InstanceBasedLearningExtractor([
                        (page, scrapes['#default'])
                        for page, scrapes, version in group
                    ]))
            else:
                self.extractors.append(SlybotIBLExtractor(list(group)))

        # generate ibl extractor for links pages
        _links_pages = [
            dict_to_page(t, 'annotated_body') for t in templates
            if t.get('page_type') == 'links'
        ]
        _links_item_descriptor = create_slybot_item_descriptor({'fields': {}})
        self._links_ibl_extractor = InstanceBasedLearningExtractor(
            [(t, _links_item_descriptor) for t in _links_pages]) \
            if _links_pages else None

        self.build_url_filter(spec)
        # Clustering
        self.template_names = [t.get('page_id') for t in spec['templates']]
        if settings.get('PAGE_CLUSTERING'):
            try:
                import page_clustering
                self.clustering = page_clustering.kmeans_from_samples(
                    spec['templates'])
                self.logger.info("Clustering activated")
            except ImportError:
                self.clustering = None
                self.logger.warning(
                    "Clustering could not be used because it is not installed")
        else:
            self.clustering = None
예제 #19
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 def scrape_page(self, page):
     if self._ex is None:
         self._ex = InstanceBasedLearningExtractor((t, None) for t in
                 self._templates)
     return self._ex.extract(page)[0]
예제 #20
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    def __init__(self, name, spec, item_schemas, all_extractors, **kw):
        super(IblSpider, self).__init__(name, **kw)
        default_item = spec['scrapes']
        self._default_schema = item_schemas[default_item]
        if not self._default_schema:
            self.log("Scraping unknown default item schema: %s" % default_item, \
                log.WARNING)

        self._item_template_pages = sorted((
            [t.get('scrapes', default_item), dict_to_page(t, 'annotated_body'),
            t.get('extractors', [])] \
            for t in spec['templates'] if t.get('page_type', 'item') == 'item'
        ), key=lambda pair: pair[0])

        # generate ibl extractor for links pages
        _links_pages = [
            dict_to_page(t, 'annotated_body') for t in spec['templates']
            if t.get('page_type') == 'links'
        ]
        _links_item_descriptor = create_slybot_item_descriptor({
            'id': "_links",
            'properties': ()
        })
        self._links_ibl_extractor = InstanceBasedLearningExtractor([(t, _links_item_descriptor) for t in _links_pages]) \
                if _links_pages else None

        self._ipages = [page for _, page, _ in self._item_template_pages]

        self.start_urls = self.start_urls or spec.get('start_urls')
        if isinstance(self.start_urls, basestring):
            self.start_urls = self.start_urls.splitlines()

        self.link_extractor = LinkExtractor()
        self.allowed_domains = self._get_allowed_domains(self._ipages)

        self.build_url_filter(spec)

        default_item_cls = get_iblitem_class(self._default_schema)
        default_item_descriptor = create_slybot_item_descriptor(
            self._default_schema)

        self.itemcls_info = {}
        for itemclass_name, triplets in itertools.groupby(
                self._item_template_pages, operator.itemgetter(0)):
            page_extractors_pairs = map(operator.itemgetter(1, 2), triplets)
            schema = item_schemas[itemclass_name]
            item_cls = get_iblitem_class(
                schema) if schema else default_item_cls

            page_descriptor_pairs = []
            for page, extractors in page_extractors_pairs:
                item_descriptor = create_slybot_item_descriptor(
                    schema) if schema else default_item_descriptor
                apply_extractors(item_descriptor, extractors, all_extractors)
                page_descriptor_pairs.append((page, item_descriptor))

            extractor = InstanceBasedLearningExtractor(page_descriptor_pairs)

            self.itemcls_info[itemclass_name] = {
                'class': item_cls,
                'descriptor': item_descriptor,
                'extractor': extractor,
            }

        self.login_requests = []
        self.form_requests = []
        for rdata in spec.get("init_requests", []):
            if rdata["type"] == "login":
                request = Request(url=rdata.pop("loginurl"),
                                  meta=rdata,
                                  callback=self.parse_login_page)
                self.login_requests.append(request)

            elif rdata["type"] == "form":
                request = Request(url=rdata.pop("form_url"),
                                  meta=rdata,
                                  callback=self.parse_form_page)
                self.form_requests.append(request)
예제 #21
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    def __init__(self, name, spec, item_schemas, all_extractors, **kw):
        super(IblSpider, self).__init__(name, **kw)

        self._item_template_pages = sorted((
            [t['scrapes'], dict_to_page(t, 'annotated_body'),
            t.get('extractors', [])] \
            for t in spec['templates'] if t.get('page_type', 'item') == 'item'
        ), key=lambda pair: pair[0])

        # generate ibl extractor for links pages
        _links_pages = [dict_to_page(t, 'annotated_body')
                for t in spec['templates'] if t.get('page_type') == 'links']
        _links_item_descriptor = create_slybot_item_descriptor({'fields': {}})
        self._links_ibl_extractor = InstanceBasedLearningExtractor([(t, _links_item_descriptor) for t in _links_pages]) \
                if _links_pages else None

        self._ipages = [page for _, page, _ in self._item_template_pages]

        self.start_urls = self.start_urls or spec.get('start_urls')
        if isinstance(self.start_urls, basestring):
            self.start_urls = self.start_urls.splitlines()

        self.html_link_extractor = HtmlLinkExtractor()
        self.rss_link_extractor = RssLinkExtractor()
        self.allowed_domains = spec.get('allowed_domains',
                                        self._get_allowed_domains(self._ipages))
        if not self.allowed_domains:
            self.allowed_domains = None
        self.build_url_filter(spec)

        self.itemcls_info = {}
        for itemclass_name, triplets in itertools.groupby(self._item_template_pages, operator.itemgetter(0)):
            page_extractors_pairs = map(operator.itemgetter(1, 2), triplets)
            schema = item_schemas[itemclass_name]
            item_cls = get_iblitem_class(schema)

            page_descriptor_pairs = []
            for page, template_extractors in page_extractors_pairs:
                item_descriptor = create_slybot_item_descriptor(schema)
                apply_extractors(item_descriptor, template_extractors, all_extractors)
                page_descriptor_pairs.append((page, item_descriptor))

            extractor = InstanceBasedLearningExtractor(page_descriptor_pairs)

            self.itemcls_info[itemclass_name] = {
                'class': item_cls,
                'descriptor': item_descriptor,
                'extractor': extractor,
            }

        self.login_requests = []
        self.form_requests = []
        for rdata in spec.get("init_requests", []):
            if rdata["type"] == "login":
                request = Request(url=rdata.pop("loginurl"), meta=rdata,
                                  callback=self.parse_login_page, dont_filter=True)
                self.login_requests.append(request)

            elif rdata["type"] == "form":
                self.generic_form = GenericForm(**kw)
                self.form_requests.append(self.get_generic_form_start_request(rdata))
예제 #22
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    def setup_bot(self, settings, spec, items, extractors):
        """
        Perform any initialization needed for crawling using this plugin
        """
        _item_template_pages = sorted(([
            t.get('scrapes'),
            dict_to_page(t, 'annotated_body'),
            t.get('extractors', []),
            t.get('version', '0.12.0')
        ] for t in spec['templates'] if t.get('page_type', 'item') == 'item'),
                                      key=lambda x: x[0])
        self.item_classes = {}
        self.template_scrapes = {
            template.get('page_id'): template['scrapes']
            for template in spec.get('templates')
        }
        self.html_link_extractor = HtmlLinkExtractor()
        for schema_name, schema in items.items():
            if schema_name not in self.item_classes:
                if not schema.get('name'):
                    schema['name'] = schema_name
                item_cls = SlybotItem.create_iblitem_class(schema)
                self.item_classes[schema_name] = item_cls

        # Create descriptors and apply additional extractors to fields
        page_descriptor_pairs = []
        self.schema_descriptors = {}
        for default, template, template_extractors, v in _item_template_pages:
            descriptors = OrderedDict()
            for schema_name, schema in items.items():
                item_descriptor = create_slybot_item_descriptor(
                    schema, schema_name)
                apply_extractors(item_descriptor, template_extractors,
                                 extractors)
                descriptors[schema_name] = item_descriptor
            descriptor = descriptors.values() or [{}]
            descriptors['#default'] = descriptors.get(default, descriptor[0])
            self.schema_descriptors[template.page_id] = descriptors['#default']
            page_descriptor_pairs.append((template, descriptors, v))
            add_extractors_to_descriptors(descriptors, extractors)

        grouped = itertools.groupby(
            sorted(page_descriptor_pairs, key=operator.itemgetter(2)),
            lambda x: x[2] < '0.13.0')
        self.extractors = []
        for version, group in grouped:
            if version:
                self.extractors.append(
                    InstanceBasedLearningExtractor([
                        (page, scrapes['#default'])
                        for page, scrapes, version in group
                    ]))
            else:
                self.extractors.append(SlybotIBLExtractor(list(group)))

        # generate ibl extractor for links pages
        _links_pages = [
            dict_to_page(t, 'annotated_body') for t in spec['templates']
            if t.get('page_type') == 'links'
        ]
        _links_item_descriptor = create_slybot_item_descriptor({'fields': {}})
        self._links_ibl_extractor = InstanceBasedLearningExtractor(
            [(t, _links_item_descriptor) for t in _links_pages]) \
            if _links_pages else None

        self.build_url_filter(spec)