Source code for scrapy.extensions.feedexport

"""
Feed Exports extension

See documentation in docs/topics/feed-exports.rst
"""

import logging
import os
import re
import sys
import warnings
from datetime import datetime
from tempfile import NamedTemporaryFile
from typing import Any, Optional, Tuple
from urllib.parse import unquote, urlparse

from twisted.internet import defer, threads
from w3lib.url import file_uri_to_path
from zope.interface import implementer, Interface

from scrapy import signals
from scrapy.exceptions import NotConfigured, ScrapyDeprecationWarning
from scrapy.extensions.postprocessing import PostProcessingManager
from scrapy.utils.boto import is_botocore_available
from scrapy.utils.conf import feed_complete_default_values_from_settings
from scrapy.utils.ftp import ftp_store_file
from scrapy.utils.log import failure_to_exc_info
from scrapy.utils.misc import create_instance, load_object
from scrapy.utils.python import get_func_args, without_none_values


logger = logging.getLogger(__name__)


def build_storage(builder, uri, *args, feed_options=None, preargs=(), **kwargs):
    argument_names = get_func_args(builder)
    if 'feed_options' in argument_names:
        kwargs['feed_options'] = feed_options
    else:
        warnings.warn(
            f"{builder.__qualname__} does not support the 'feed_options' keyword argument. Add a "
            "'feed_options' parameter to its signature to remove this "
            "warning. This parameter will become mandatory in a future "
            "version of Scrapy.",
            category=ScrapyDeprecationWarning
        )
    return builder(*preargs, uri, *args, **kwargs)


[docs]class ItemFilter: """ This will be used by FeedExporter to decide if an item should be allowed to be exported to a particular feed. :param feed_options: feed specific options passed from FeedExporter :type feed_options: dict """ feed_options: Optional[dict] item_classes: Tuple def __init__(self, feed_options: Optional[dict]) -> None: self.feed_options = feed_options if feed_options is not None: self.item_classes = tuple( load_object(item_class) for item_class in feed_options.get("item_classes") or () ) else: self.item_classes = tuple()
[docs] def accepts(self, item: Any) -> bool: """ Return ``True`` if `item` should be exported or ``False`` otherwise. :param item: scraped item which user wants to check if is acceptable :type item: :ref:`Scrapy items <topics-items>` :return: `True` if accepted, `False` otherwise :rtype: bool """ if self.item_classes: return isinstance(item, self.item_classes) return True # accept all items by default
class IFeedStorage(Interface): """Interface that all Feed Storages must implement""" def __init__(uri, *, feed_options=None): """Initialize the storage with the parameters given in the URI and the feed-specific options (see :setting:`FEEDS`)""" def open(spider): """Open the storage for the given spider. It must return a file-like object that will be used for the exporters""" def store(file): """Store the given file stream""" @implementer(IFeedStorage) class BlockingFeedStorage: def open(self, spider): path = spider.crawler.settings['FEED_TEMPDIR'] if path and not os.path.isdir(path): raise OSError('Not a Directory: ' + str(path)) return NamedTemporaryFile(prefix='feed-', dir=path) def store(self, file): return threads.deferToThread(self._store_in_thread, file) def _store_in_thread(self, file): raise NotImplementedError @implementer(IFeedStorage) class StdoutFeedStorage: def __init__(self, uri, _stdout=None, *, feed_options=None): if not _stdout: _stdout = sys.stdout.buffer self._stdout = _stdout if feed_options and feed_options.get('overwrite', False) is True: logger.warning('Standard output (stdout) storage does not support ' 'overwriting. To suppress this warning, remove the ' 'overwrite option from your FEEDS setting, or set ' 'it to False.') def open(self, spider): return self._stdout def store(self, file): pass @implementer(IFeedStorage) class FileFeedStorage: def __init__(self, uri, *, feed_options=None): self.path = file_uri_to_path(uri) feed_options = feed_options or {} self.write_mode = 'wb' if feed_options.get('overwrite', False) else 'ab' def open(self, spider): dirname = os.path.dirname(self.path) if dirname and not os.path.exists(dirname): os.makedirs(dirname) return open(self.path, self.write_mode) def store(self, file): file.close() class S3FeedStorage(BlockingFeedStorage): def __init__(self, uri, access_key=None, secret_key=None, acl=None, endpoint_url=None, *, feed_options=None, session_token=None): if not is_botocore_available(): raise NotConfigured('missing botocore library') u = urlparse(uri) self.bucketname = u.hostname self.access_key = u.username or access_key self.secret_key = u.password or secret_key self.session_token = session_token self.keyname = u.path[1:] # remove first "/" self.acl = acl self.endpoint_url = endpoint_url import botocore.session session = botocore.session.get_session() self.s3_client = session.create_client( 's3', aws_access_key_id=self.access_key, aws_secret_access_key=self.secret_key, aws_session_token=self.session_token, endpoint_url=self.endpoint_url) if feed_options and feed_options.get('overwrite', True) is False: logger.warning('S3 does not support appending to files. To ' 'suppress this warning, remove the overwrite ' 'option from your FEEDS setting or set it to True.') @classmethod def from_crawler(cls, crawler, uri, *, feed_options=None): return build_storage( cls, uri, access_key=crawler.settings['AWS_ACCESS_KEY_ID'], secret_key=crawler.settings['AWS_SECRET_ACCESS_KEY'], session_token=crawler.settings['AWS_SESSION_TOKEN'], acl=crawler.settings['FEED_STORAGE_S3_ACL'] or None, endpoint_url=crawler.settings['AWS_ENDPOINT_URL'] or None, feed_options=feed_options, ) def _store_in_thread(self, file): file.seek(0) kwargs = {'ACL': self.acl} if self.acl else {} self.s3_client.put_object( Bucket=self.bucketname, Key=self.keyname, Body=file, **kwargs) file.close() class GCSFeedStorage(BlockingFeedStorage): def __init__(self, uri, project_id, acl): self.project_id = project_id self.acl = acl u = urlparse(uri) self.bucket_name = u.hostname self.blob_name = u.path[1:] # remove first "/" @classmethod def from_crawler(cls, crawler, uri): return cls( uri, crawler.settings['GCS_PROJECT_ID'], crawler.settings['FEED_STORAGE_GCS_ACL'] or None ) def _store_in_thread(self, file): file.seek(0) from google.cloud.storage import Client client = Client(project=self.project_id) bucket = client.get_bucket(self.bucket_name) blob = bucket.blob(self.blob_name) blob.upload_from_file(file, predefined_acl=self.acl) class FTPFeedStorage(BlockingFeedStorage): def __init__(self, uri, use_active_mode=False, *, feed_options=None): u = urlparse(uri) self.host = u.hostname self.port = int(u.port or '21') self.username = u.username self.password = unquote(u.password or '') self.path = u.path self.use_active_mode = use_active_mode self.overwrite = not feed_options or feed_options.get('overwrite', True) @classmethod def from_crawler(cls, crawler, uri, *, feed_options=None): return build_storage( cls, uri, crawler.settings.getbool('FEED_STORAGE_FTP_ACTIVE'), feed_options=feed_options, ) def _store_in_thread(self, file): ftp_store_file( path=self.path, file=file, host=self.host, port=self.port, username=self.username, password=self.password, use_active_mode=self.use_active_mode, overwrite=self.overwrite, ) class _FeedSlot: def __init__(self, file, exporter, storage, uri, format, store_empty, batch_id, uri_template, filter): self.file = file self.exporter = exporter self.storage = storage # feed params self.batch_id = batch_id self.format = format self.store_empty = store_empty self.uri_template = uri_template self.uri = uri self.filter = filter # flags self.itemcount = 0 self._exporting = False def start_exporting(self): if not self._exporting: self.exporter.start_exporting() self._exporting = True def finish_exporting(self): if self._exporting: self.exporter.finish_exporting() self._exporting = False class FeedExporter: @classmethod def from_crawler(cls, crawler): exporter = cls(crawler) crawler.signals.connect(exporter.open_spider, signals.spider_opened) crawler.signals.connect(exporter.close_spider, signals.spider_closed) crawler.signals.connect(exporter.item_scraped, signals.item_scraped) return exporter def __init__(self, crawler): self.crawler = crawler self.settings = crawler.settings self.feeds = {} self.slots = [] self.filters = {} if not self.settings['FEEDS'] and not self.settings['FEED_URI']: raise NotConfigured # Begin: Backward compatibility for FEED_URI and FEED_FORMAT settings if self.settings['FEED_URI']: warnings.warn( 'The `FEED_URI` and `FEED_FORMAT` settings have been deprecated in favor of ' 'the `FEEDS` setting. Please see the `FEEDS` setting docs for more details', category=ScrapyDeprecationWarning, stacklevel=2, ) uri = str(self.settings['FEED_URI']) # handle pathlib.Path objects feed_options = {'format': self.settings.get('FEED_FORMAT', 'jsonlines')} self.feeds[uri] = feed_complete_default_values_from_settings(feed_options, self.settings) self.filters[uri] = self._load_filter(feed_options) # End: Backward compatibility for FEED_URI and FEED_FORMAT settings # 'FEEDS' setting takes precedence over 'FEED_URI' for uri, feed_options in self.settings.getdict('FEEDS').items(): uri = str(uri) # handle pathlib.Path objects self.feeds[uri] = feed_complete_default_values_from_settings(feed_options, self.settings) self.filters[uri] = self._load_filter(feed_options) self.storages = self._load_components('FEED_STORAGES') self.exporters = self._load_components('FEED_EXPORTERS') for uri, feed_options in self.feeds.items(): if not self._storage_supported(uri, feed_options): raise NotConfigured if not self._settings_are_valid(): raise NotConfigured if not self._exporter_supported(feed_options['format']): raise NotConfigured def open_spider(self, spider): for uri, feed_options in self.feeds.items(): uri_params = self._get_uri_params(spider, feed_options['uri_params']) self.slots.append(self._start_new_batch( batch_id=1, uri=uri % uri_params, feed_options=feed_options, spider=spider, uri_template=uri, )) def close_spider(self, spider): deferred_list = [] for slot in self.slots: d = self._close_slot(slot, spider) deferred_list.append(d) return defer.DeferredList(deferred_list) if deferred_list else None def _close_slot(self, slot, spider): if not slot.itemcount and not slot.store_empty: # We need to call slot.storage.store nonetheless to get the file # properly closed. return defer.maybeDeferred(slot.storage.store, slot.file) slot.finish_exporting() logmsg = f"{slot.format} feed ({slot.itemcount} items) in: {slot.uri}" d = defer.maybeDeferred(slot.storage.store, slot.file) d.addCallback( self._handle_store_success, logmsg, spider, type(slot.storage).__name__ ) d.addErrback( self._handle_store_error, logmsg, spider, type(slot.storage).__name__ ) return d def _handle_store_error(self, f, logmsg, spider, slot_type): logger.error( "Error storing %s", logmsg, exc_info=failure_to_exc_info(f), extra={'spider': spider} ) self.crawler.stats.inc_value(f"feedexport/failed_count/{slot_type}") def _handle_store_success(self, f, logmsg, spider, slot_type): logger.info( "Stored %s", logmsg, extra={'spider': spider} ) self.crawler.stats.inc_value(f"feedexport/success_count/{slot_type}") def _start_new_batch(self, batch_id, uri, feed_options, spider, uri_template): """ Redirect the output data stream to a new file. Execute multiple times if FEED_EXPORT_BATCH_ITEM_COUNT setting or FEEDS.batch_item_count is specified :param batch_id: sequence number of current batch :param uri: uri of the new batch to start :param feed_options: dict with parameters of feed :param spider: user spider :param uri_template: template of uri which contains %(batch_time)s or %(batch_id)d to create new uri """ storage = self._get_storage(uri, feed_options) file = storage.open(spider) if "postprocessing" in feed_options: file = PostProcessingManager(feed_options["postprocessing"], file, feed_options) exporter = self._get_exporter( file=file, format=feed_options['format'], fields_to_export=feed_options['fields'], encoding=feed_options['encoding'], indent=feed_options['indent'], **feed_options['item_export_kwargs'], ) slot = _FeedSlot( file=file, exporter=exporter, storage=storage, uri=uri, format=feed_options['format'], store_empty=feed_options['store_empty'], batch_id=batch_id, uri_template=uri_template, filter=self.filters[uri_template] ) if slot.store_empty: slot.start_exporting() return slot def item_scraped(self, item, spider): slots = [] for slot in self.slots: if not slot.filter.accepts(item): slots.append(slot) # if slot doesn't accept item, continue with next slot continue slot.start_exporting() slot.exporter.export_item(item) slot.itemcount += 1 # create new slot for each slot with itemcount == FEED_EXPORT_BATCH_ITEM_COUNT and close the old one if ( self.feeds[slot.uri_template]['batch_item_count'] and slot.itemcount >= self.feeds[slot.uri_template]['batch_item_count'] ): uri_params = self._get_uri_params(spider, self.feeds[slot.uri_template]['uri_params'], slot) self._close_slot(slot, spider) slots.append(self._start_new_batch( batch_id=slot.batch_id + 1, uri=slot.uri_template % uri_params, feed_options=self.feeds[slot.uri_template], spider=spider, uri_template=slot.uri_template, )) else: slots.append(slot) self.slots = slots def _load_components(self, setting_prefix): conf = without_none_values(self.settings.getwithbase(setting_prefix)) d = {} for k, v in conf.items(): try: d[k] = load_object(v) except NotConfigured: pass return d def _exporter_supported(self, format): if format in self.exporters: return True logger.error("Unknown feed format: %(format)s", {'format': format}) def _settings_are_valid(self): """ If FEED_EXPORT_BATCH_ITEM_COUNT setting or FEEDS.batch_item_count is specified uri has to contain %(batch_time)s or %(batch_id)d to distinguish different files of partial output """ for uri_template, values in self.feeds.items(): if values['batch_item_count'] and not re.search(r'%\(batch_time\)s|%\(batch_id\)', uri_template): logger.error( '%%(batch_time)s or %%(batch_id)d must be in the feed URI (%s) if FEED_EXPORT_BATCH_ITEM_COUNT ' 'setting or FEEDS.batch_item_count is specified and greater than 0. For more info see: ' 'https://docs.scrapy.org/en/latest/topics/feed-exports.html#feed-export-batch-item-count', uri_template ) return False return True def _storage_supported(self, uri, feed_options): scheme = urlparse(uri).scheme if scheme in self.storages: try: self._get_storage(uri, feed_options) return True except NotConfigured as e: logger.error("Disabled feed storage scheme: %(scheme)s. " "Reason: %(reason)s", {'scheme': scheme, 'reason': str(e)}) else: logger.error("Unknown feed storage scheme: %(scheme)s", {'scheme': scheme}) def _get_instance(self, objcls, *args, **kwargs): return create_instance( objcls, self.settings, getattr(self, 'crawler', None), *args, **kwargs) def _get_exporter(self, file, format, *args, **kwargs): return self._get_instance(self.exporters[format], file, *args, **kwargs) def _get_storage(self, uri, feed_options): """Fork of create_instance specific to feed storage classes It supports not passing the *feed_options* parameters to classes that do not support it, and issuing a deprecation warning instead. """ feedcls = self.storages[urlparse(uri).scheme] crawler = getattr(self, 'crawler', None) def build_instance(builder, *preargs): return build_storage(builder, uri, feed_options=feed_options, preargs=preargs) if crawler and hasattr(feedcls, 'from_crawler'): instance = build_instance(feedcls.from_crawler, crawler) method_name = 'from_crawler' elif hasattr(feedcls, 'from_settings'): instance = build_instance(feedcls.from_settings, self.settings) method_name = 'from_settings' else: instance = build_instance(feedcls) method_name = '__new__' if instance is None: raise TypeError(f"{feedcls.__qualname__}.{method_name} returned None") return instance def _get_uri_params(self, spider, uri_params, slot=None): params = {} for k in dir(spider): params[k] = getattr(spider, k) utc_now = datetime.utcnow() params['time'] = utc_now.replace(microsecond=0).isoformat().replace(':', '-') params['batch_time'] = utc_now.isoformat().replace(':', '-') params['batch_id'] = slot.batch_id + 1 if slot is not None else 1 uripar_function = load_object(uri_params) if uri_params else lambda x, y: None uripar_function(params, spider) return params def _load_filter(self, feed_options): # load the item filter if declared else load the default filter class item_filter_class = load_object(feed_options.get("item_filter", ItemFilter)) return item_filter_class(feed_options)