"""
Feed Exports extension
See documentation in docs/topics/feed-exports.rst
"""
import logging
import re
import sys
import warnings
from datetime import datetime, timezone
from pathlib import Path, PureWindowsPath
from tempfile import NamedTemporaryFile
from typing import IO, Any, Callable, Dict, List, Optional, Tuple, Union
from urllib.parse import unquote, urlparse
from twisted.internet import defer, threads
from twisted.internet.defer import DeferredList
from w3lib.url import file_uri_to_path
from zope.interface import Interface, implementer
from scrapy import Spider, 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.defer import maybe_deferred_to_future
from scrapy.utils.deprecate import create_deprecated_class
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__)
try:
import boto3 # noqa: F401
IS_BOTO3_AVAILABLE = True
except ImportError:
IS_BOTO3_AVAILABLE = False
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 Path(path).is_dir():
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) -> IO[Any]:
dirname = Path(self.path).parent
if dirname and not dirname.exists():
dirname.mkdir(parents=True)
return Path(self.path).open(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,
region_name=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
self.region_name = region_name
if IS_BOTO3_AVAILABLE:
import boto3.session
session = boto3.session.Session()
self.s3_client = session.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,
region_name=self.region_name,
)
else:
warnings.warn(
"`botocore` usage has been deprecated for S3 feed "
"export, please use `boto3` to avoid problems",
category=ScrapyDeprecationWarning,
)
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,
region_name=self.region_name,
)
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,
region_name=crawler.settings["AWS_REGION_NAME"] or None,
feed_options=feed_options,
)
def _store_in_thread(self, file):
file.seek(0)
if IS_BOTO3_AVAILABLE:
kwargs = {"ExtraArgs": {"ACL": self.acl}} if self.acl else {}
self.s3_client.upload_fileobj(
Bucket=self.bucketname, Key=self.keyname, Fileobj=file, **kwargs
)
else:
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: str,
use_active_mode: bool = False,
*,
feed_options: Optional[Dict[str, Any]] = None,
):
u = urlparse(uri)
if not u.hostname:
raise ValueError(f"Got a storage URI without a hostname: {uri}")
self.host: str = u.hostname
self.port: int = int(u.port or "21")
self.username: str = u.username or ""
self.password: str = unquote(u.password or "")
self.path: str = u.path
self.use_active_mode: bool = use_active_mode
self.overwrite: bool = 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,
storage,
uri,
format,
store_empty,
batch_id,
uri_template,
filter,
feed_options,
spider,
exporters,
settings,
crawler,
):
self.file = None
self.exporter = None
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
# exporter params
self.feed_options = feed_options
self.spider = spider
self.exporters = exporters
self.settings = settings
self.crawler = crawler
# flags
self.itemcount = 0
self._exporting = False
self._fileloaded = False
def start_exporting(self):
if not self._fileloaded:
self.file = self.storage.open(self.spider)
if "postprocessing" in self.feed_options:
self.file = PostProcessingManager(
self.feed_options["postprocessing"], self.file, self.feed_options
)
self.exporter = self._get_exporter(
file=self.file,
format=self.feed_options["format"],
fields_to_export=self.feed_options["fields"],
encoding=self.feed_options["encoding"],
indent=self.feed_options["indent"],
**self.feed_options["item_export_kwargs"],
)
self._fileloaded = True
if not self._exporting:
self.exporter.start_exporting()
self._exporting = True
def _get_instance(self, objcls, *args, **kwargs):
return create_instance(objcls, self.settings, self.crawler, *args, **kwargs)
def _get_exporter(self, file, format, *args, **kwargs):
return self._get_instance(self.exporters[format], file, *args, **kwargs)
def finish_exporting(self):
if self._exporting:
self.exporter.finish_exporting()
self._exporting = False
_FeedSlot = create_deprecated_class(
name="_FeedSlot",
new_class=FeedSlot,
)
class FeedExporter:
_pending_deferreds: List[defer.Deferred] = []
@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 = self.settings["FEED_URI"]
# handle pathlib.Path objects
uri = str(uri) if not isinstance(uri, Path) else uri.absolute().as_uri()
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():
# handle pathlib.Path objects
uri = str(uri) if not isinstance(uri, Path) else uri.absolute().as_uri()
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,
)
)
async def close_spider(self, spider):
for slot in self.slots:
self._close_slot(slot, spider)
# Await all deferreds
if self._pending_deferreds:
await maybe_deferred_to_future(DeferredList(self._pending_deferreds))
# Send FEED_EXPORTER_CLOSED signal
await maybe_deferred_to_future(
self.crawler.signals.send_catch_log_deferred(signals.feed_exporter_closed)
)
def _close_slot(self, slot, spider):
def get_file(slot_):
if isinstance(slot_.file, PostProcessingManager):
slot_.file.close()
return slot_.file.file
return slot_.file
if slot.itemcount:
# Normal case
slot.finish_exporting()
elif slot.store_empty and slot.batch_id == 1:
# Need to store the empty file
slot.start_exporting()
slot.finish_exporting()
else:
# In this case, the file is not stored, so no processing is required.
return None
logmsg = f"{slot.format} feed ({slot.itemcount} items) in: {slot.uri}"
d = defer.maybeDeferred(slot.storage.store, get_file(slot))
d.addCallback(
self._handle_store_success, logmsg, spider, type(slot.storage).__name__
)
d.addErrback(
self._handle_store_error, logmsg, spider, type(slot.storage).__name__
)
self._pending_deferreds.append(d)
d.addCallback(
lambda _: self.crawler.signals.send_catch_log_deferred(
signals.feed_slot_closed, slot=slot
)
)
d.addBoth(lambda _: self._pending_deferreds.remove(d))
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)
slot = FeedSlot(
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],
feed_options=feed_options,
spider=spider,
exporters=self.exporters,
settings=self.settings,
crawler=getattr(self, "crawler", None),
)
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 or PureWindowsPath(uri).drive:
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_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.get(urlparse(uri).scheme, self.storages["file"])
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: Spider,
uri_params_function: Optional[Union[str, Callable[[dict, Spider], dict]]],
slot: Optional[FeedSlot] = None,
) -> dict:
params = {}
for k in dir(spider):
params[k] = getattr(spider, k)
utc_now = datetime.now(tz=timezone.utc)
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_function)
if uri_params_function
else lambda params, _: params
)
new_params = uripar_function(params, spider)
return new_params if new_params is not None else 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)