Settings

Settings

The Scrapy settings allows you to customize the behaviour of all Scrapy components, including the core, extensions, pipelines and spiders themselves.

The infrastructure of the settings provides a global namespace of key-value mappings that the code can use to pull configuration values from. The settings can be populated through different mechanisms, which are described below.

The settings are also the mechanism for selecting the currently active Scrapy project (in case you have many).

For a list of available built-in settings see: Built-in settings reference.

Designating the settings

When you use Scrapy, you have to tell it which settings you’re using. You can do this by using an environment variable, SCRAPY_SETTINGS_MODULE.

The value of SCRAPY_SETTINGS_MODULE should be in Python path syntax, e.g. myproject.settings. Note that the settings module should be on the Python import search path.

Populating the settings

Settings can be populated using different mechanisms, each of which having a different precedence. Here is the list of them in decreasing order of precedence:

Command line options (most precedence)

Settings per-spider

Project settings module

Default settings per-command

Default global settings (less precedence)

The population of these settings sources is taken care of internally, but a manual handling is possible using API calls. See the Settings API topic for reference.

These mechanisms are described in more detail below.

1. Command line options

Arguments provided by the command line are the ones that take most precedence, overriding any other options. You can explicitly override one (or more) settings using the -s (or --set) command line option.

Example:

scrapy crawl myspider -s LOG_FILE=scrapy.log

2. Settings per-spider

Spiders (See the Spiders chapter for reference) can define their own settings that will take precedence and override the project ones. They can do so by setting their custom_settings attribute:

class MySpider(scrapy.Spider):
    name = 'myspider'
    custom_settings = {
        'SOME_SETTING': 'some value',
    }

3. Project settings module

The project settings module is the standard configuration file for your Scrapy project, it’s where most of your custom settings will be populated. For a standard Scrapy project, this means you’ll be adding or changing the settings in the settings.py file created for your project.

4. Default settings per-command

Each Scrapy tool command can have its own default settings, which override the global default settings. Those custom command settings are specified in the default_settings attribute of the command class.

5. Default global settings

The global defaults are located in the scrapy.settings.default_settings module and documented in the Built-in settings reference section.

How to access settings

In a spider, the settings are available through self.settings:

class MySpider(scrapy.Spider):
    name = 'myspider'
    start_urls = ['http://example.com']
    def parse(self, response):
        print("Existing settings: %s" % self.settings.attributes.keys())

Note

The settings attribute is set in the base Spider class after the spider is initialized. If you want to use the settings before the initialization (e.g., in your spider’s __init__() method), you’ll need to override the from_crawler() method.

Settings can be accessed through the scrapy.crawler.Crawler.settings attribute of the Crawler that is passed to from_crawler method in extensions, middlewares and item pipelines:

class MyExtension:
    def __init__(self, log_is_enabled=False):
        if log_is_enabled:
            print("log is enabled!")
    @classmethod
    def from_crawler(cls, crawler):
        settings = crawler.settings
        return cls(settings.getbool('LOG_ENABLED'))

The settings object can be used like a dict (e.g., settings['LOG_ENABLED']), but it’s usually preferred to extract the setting in the format you need it to avoid type errors, using one of the methods provided by the Settings API.

Rationale for setting names

Setting names are usually prefixed with the component that they configure. For example, proper setting names for a fictional robots.txt extension would be ROBOTSTXT_ENABLED, ROBOTSTXT_OBEY, ROBOTSTXT_CACHEDIR, etc.

Built-in settings reference

Here’s a list of all available Scrapy settings, in alphabetical order, along with their default values and the scope where they apply.

The scope, where available, shows where the setting is being used, if it’s tied to any particular component. In that case the module of that component will be shown, typically an extension, middleware or pipeline. It also means that the component must be enabled in order for the setting to have any effect.

AWS_ACCESS_KEY_ID

Default: None

The AWS access key used by code that requires access to Amazon Web services, such as the S3 feed storage backend.

AWS_SECRET_ACCESS_KEY

Default: None

The AWS secret key used by code that requires access to Amazon Web services, such as the S3 feed storage backend.

AWS_ENDPOINT_URL

Default: None

Endpoint URL used for S3-like storage, for example Minio or s3.scality.

AWS_USE_SSL

Default: None

Use this option if you want to disable SSL connection for communication with S3 or S3-like storage. By default SSL will be used.

AWS_VERIFY

Default: None

Verify SSL connection between Scrapy and S3 or S3-like storage. By default SSL verification will occur.

AWS_REGION_NAME

Default: None

The name of the region associated with the AWS client.

BOT_NAME

Default: 'scrapybot'

The name of the bot implemented by this Scrapy project (also known as the project name). This name will be used for the logging too.

It’s automatically populated with your project name when you create your project with the startproject command.

CONCURRENT_ITEMS

Default: 100

Maximum number of concurrent items (per response) to process in parallel in the Item Processor (also known as the Item Pipeline).

CONCURRENT_REQUESTS

Default: 16

The maximum number of concurrent (i.e. simultaneous) requests that will be performed by the Scrapy downloader.

CONCURRENT_REQUESTS_PER_DOMAIN

Default: 8

The maximum number of concurrent (i.e. simultaneous) requests that will be performed to any single domain.

See also: AutoThrottle extension and its AUTOTHROTTLE_TARGET_CONCURRENCY option.

CONCURRENT_REQUESTS_PER_IP

Default: 0

The maximum number of concurrent (i.e. simultaneous) requests that will be performed to any single IP. If non-zero, the CONCURRENT_REQUESTS_PER_DOMAIN setting is ignored, and this one is used instead. In other words, concurrency limits will be applied per IP, not per domain.

This setting also affects DOWNLOAD_DELAY and AutoThrottle extension: if CONCURRENT_REQUESTS_PER_IP is non-zero, download delay is enforced per IP, not per domain.

DEFAULT_ITEM_CLASS

Default: 'scrapy.item.Item'

The default class that will be used for instantiating items in the the Scrapy shell.

DEFAULT_REQUEST_HEADERS

Default:

{
    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
    'Accept-Language': 'en',
}

The default headers used for Scrapy HTTP Requests. They’re populated in the DefaultHeadersMiddleware.

DEPTH_LIMIT

Default: 0

Scope: scrapy.spidermiddlewares.depth.DepthMiddleware

The maximum depth that will be allowed to crawl for any site. If zero, no limit will be imposed.

DEPTH_PRIORITY

Default: 0

Scope: scrapy.spidermiddlewares.depth.DepthMiddleware

An integer that is used to adjust the priority of a Request based on its depth.

The priority of a request is adjusted as follows:

request.priority = request.priority - ( depth * DEPTH_PRIORITY )

As depth increases, positive values of DEPTH_PRIORITY decrease request priority (BFO), while negative values increase request priority (DFO). See also Does Scrapy crawl in breadth-first or depth-first order?.

Note

This setting adjusts priority in the opposite way compared to other priority settings REDIRECT_PRIORITY_ADJUST and RETRY_PRIORITY_ADJUST.

DEPTH_STATS_VERBOSE

Default: False

Scope: scrapy.spidermiddlewares.depth.DepthMiddleware

Whether to collect verbose depth stats. If this is enabled, the number of requests for each depth is collected in the stats.

DNSCACHE_ENABLED

Default: True

Whether to enable DNS in-memory cache.

DNSCACHE_SIZE

Default: 10000

DNS in-memory cache size.

DNS_RESOLVER

New in version 2.0.

Default: 'scrapy.resolver.CachingThreadedResolver'

The class to be used to resolve DNS names. The default scrapy.resolver.CachingThreadedResolver supports specifying a timeout for DNS requests via the DNS_TIMEOUT setting, but works only with IPv4 addresses. Scrapy provides an alternative resolver, scrapy.resolver.CachingHostnameResolver, which supports IPv4/IPv6 addresses but does not take the DNS_TIMEOUT setting into account.

DNS_TIMEOUT

Default: 60

Timeout for processing of DNS queries in seconds. Float is supported.

DOWNLOADER

Default: 'scrapy.core.downloader.Downloader'

The downloader to use for crawling.

DOWNLOADER_HTTPCLIENTFACTORY

Default: 'scrapy.core.downloader.webclient.ScrapyHTTPClientFactory'

Defines a Twisted protocol.ClientFactory class to use for HTTP/1.0 connections (for HTTP10DownloadHandler).

Note

HTTP/1.0 is rarely used nowadays so you can safely ignore this setting, unless you use Twisted<11.1, or if you really want to use HTTP/1.0 and override DOWNLOAD_HANDLERS_BASE for http(s) scheme accordingly, i.e. to 'scrapy.core.downloader.handlers.http.HTTP10DownloadHandler'.

DOWNLOADER_CLIENTCONTEXTFACTORY

Default: 'scrapy.core.downloader.contextfactory.ScrapyClientContextFactory'

Represents the classpath to the ContextFactory to use.

Here, “ContextFactory” is a Twisted term for SSL/TLS contexts, defining the TLS/SSL protocol version to use, whether to do certificate verification, or even enable client-side authentication (and various other things).

Note

Scrapy default context factory does NOT perform remote server certificate verification. This is usually fine for web scraping.

If you do need remote server certificate verification enabled, Scrapy also has another context factory class that you can set, 'scrapy.core.downloader.contextfactory.BrowserLikeContextFactory', which uses the platform’s certificates to validate remote endpoints. This is only available if you use Twisted>=14.0.

If you do use a custom ContextFactory, make sure its __init__ method accepts a method parameter (this is the OpenSSL.SSL method mapping DOWNLOADER_CLIENT_TLS_METHOD), a tls_verbose_logging parameter (bool) and a tls_ciphers parameter (see DOWNLOADER_CLIENT_TLS_CIPHERS).

DOWNLOADER_CLIENT_TLS_CIPHERS

Default: 'DEFAULT'

Use this setting to customize the TLS/SSL ciphers used by the default HTTP/1.1 downloader.

The setting should contain a string in the OpenSSL cipher list format, these ciphers will be used as client ciphers. Changing this setting may be necessary to access certain HTTPS websites: for example, you may need to use 'DEFAULT:!DH' for a website with weak DH parameters or enable a specific cipher that is not included in DEFAULT if a website requires it.

DOWNLOADER_CLIENT_TLS_METHOD

Default: 'TLS'

Use this setting to customize the TLS/SSL method used by the default HTTP/1.1 downloader.

This setting must be one of these string values:

'TLS': maps to OpenSSL’s TLS_method() (a.k.a SSLv23_method()), which allows protocol negotiation, starting from the highest supported by the platform; default, recommended
'TLSv1.0': this value forces HTTPS connections to use TLS version 1.0 ; set this if you want the behavior of Scrapy<1.1
'TLSv1.1': forces TLS version 1.1
'TLSv1.2': forces TLS version 1.2
'SSLv3': forces SSL version 3 (not recommended)

Note

We recommend that you use PyOpenSSL>=0.13 and Twisted>=0.13 or above (Twisted>=14.0 if you can).

DOWNLOADER_CLIENT_TLS_VERBOSE_LOGGING

Default: False

Setting this to True will enable DEBUG level messages about TLS connection parameters after establishing HTTPS connections. The kind of information logged depends on the versions of OpenSSL and pyOpenSSL.

This setting is only used for the default DOWNLOADER_CLIENTCONTEXTFACTORY.

DOWNLOADER_MIDDLEWARES

Default:: {}

A dict containing the downloader middlewares enabled in your project, and their orders. For more info see Activating a downloader middleware.

DOWNLOADER_MIDDLEWARES_BASE

Default:

{
    'scrapy.downloadermiddlewares.robotstxt.RobotsTxtMiddleware': 100,
    'scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware': 300,
    'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware': 350,
    'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware': 400,
    'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware': 500,
    'scrapy.downloadermiddlewares.retry.RetryMiddleware': 550,
    'scrapy.downloadermiddlewares.ajaxcrawl.AjaxCrawlMiddleware': 560,
    'scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware': 580,
    'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware': 590,
    'scrapy.downloadermiddlewares.redirect.RedirectMiddleware': 600,
    'scrapy.downloadermiddlewares.cookies.CookiesMiddleware': 700,
    'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware': 750,
    'scrapy.downloadermiddlewares.stats.DownloaderStats': 850,
    'scrapy.downloadermiddlewares.httpcache.HttpCacheMiddleware': 900,
}

A dict containing the downloader middlewares enabled by default in Scrapy. Low orders are closer to the engine, high orders are closer to the downloader. You should never modify this setting in your project, modify DOWNLOADER_MIDDLEWARES instead. For more info see Activating a downloader middleware.

DOWNLOADER_STATS

Default: True

Whether to enable downloader stats collection.

DOWNLOAD_DELAY

Default: 0

The amount of time (in secs) that the downloader should wait before downloading consecutive pages from the same website. This can be used to throttle the crawling speed to avoid hitting servers too hard. Decimal numbers are supported. Example:

DOWNLOAD_DELAY = 0.25    # 250 ms of delay

This setting is also affected by the RANDOMIZE_DOWNLOAD_DELAY setting (which is enabled by default). By default, Scrapy doesn’t wait a fixed amount of time between requests, but uses a random interval between 0.5 * DOWNLOAD_DELAY and 1.5 * DOWNLOAD_DELAY.

When CONCURRENT_REQUESTS_PER_IP is non-zero, delays are enforced per ip address instead of per domain.

You can also change this setting per spider by setting download_delay spider attribute.

DOWNLOAD_HANDLERS

Default: {}

A dict containing the request downloader handlers enabled in your project. See DOWNLOAD_HANDLERS_BASE for example format.

DOWNLOAD_HANDLERS_BASE

Default:

{
    'file': 'scrapy.core.downloader.handlers.file.FileDownloadHandler',
    'http': 'scrapy.core.downloader.handlers.http.HTTPDownloadHandler',
    'https': 'scrapy.core.downloader.handlers.http.HTTPDownloadHandler',
    's3': 'scrapy.core.downloader.handlers.s3.S3DownloadHandler',
    'ftp': 'scrapy.core.downloader.handlers.ftp.FTPDownloadHandler',
}

A dict containing the request download handlers enabled by default in Scrapy. You should never modify this setting in your project, modify DOWNLOAD_HANDLERS instead.

You can disable any of these download handlers by assigning None to their URI scheme in DOWNLOAD_HANDLERS. E.g., to disable the built-in FTP handler (without replacement), place this in your settings.py:

DOWNLOAD_HANDLERS = {
    'ftp': None,
}

DOWNLOAD_TIMEOUT

Default: 180

The amount of time (in secs) that the downloader will wait before timing out.

Note

This timeout can be set per spider using download_timeout spider attribute and per-request using download_timeout Request.meta key.

DOWNLOAD_MAXSIZE

Default: 1073741824 (1024MB)

The maximum response size (in bytes) that downloader will download.

If you want to disable it set to 0.

Note

This size can be set per spider using download_maxsize spider attribute and per-request using download_maxsize Request.meta key.

This feature needs Twisted >= 11.1.

DOWNLOAD_WARNSIZE

Default: 33554432 (32MB)

The response size (in bytes) that downloader will start to warn.

If you want to disable it set to 0.

Note

This size can be set per spider using download_warnsize spider attribute and per-request using download_warnsize Request.meta key.

This feature needs Twisted >= 11.1.

DOWNLOAD_FAIL_ON_DATALOSS

Default: True

Whether or not to fail on broken responses, that is, declared Content-Length does not match content sent by the server or chunked response was not properly finish. If True, these responses raise a ResponseFailed([_DataLoss]) error. If False, these responses are passed through and the flag dataloss is added to the response, i.e.: 'dataloss' in response.flags is True.

Optionally, this can be set per-request basis by using the download_fail_on_dataloss Request.meta key to False.

Note

A broken response, or data loss error, may happen under several circumstances, from server misconfiguration to network errors to data corruption. It is up to the user to decide if it makes sense to process broken responses considering they may contain partial or incomplete content. If RETRY_ENABLED is True and this setting is set to True, the ResponseFailed([_DataLoss]) failure will be retried as usual.

DUPEFILTER_CLASS

Default: 'scrapy.dupefilters.RFPDupeFilter'

The class used to detect and filter duplicate requests.

The default (RFPDupeFilter) filters based on request fingerprint using the scrapy.utils.request.request_fingerprint function. In order to change the way duplicates are checked you could subclass RFPDupeFilter and override its request_fingerprint method. This method should accept scrapy Request object and return its fingerprint (a string).

You can disable filtering of duplicate requests by setting DUPEFILTER_CLASS to 'scrapy.dupefilters.BaseDupeFilter'. Be very careful about this however, because you can get into crawling loops. It’s usually a better idea to set the dont_filter parameter to True on the specific Request that should not be filtered.

DUPEFILTER_DEBUG

Default: False

By default, RFPDupeFilter only logs the first duplicate request. Setting DUPEFILTER_DEBUG to True will make it log all duplicate requests.

EDITOR

Default: vi (on Unix systems) or the IDLE editor (on Windows)

The editor to use for editing spiders with the edit command. Additionally, if the EDITOR environment variable is set, the edit command will prefer it over the default setting.

EXTENSIONS

Default:: {}

A dict containing the extensions enabled in your project, and their orders.

EXTENSIONS_BASE

Default:

{
    'scrapy.extensions.corestats.CoreStats': 0,
    'scrapy.extensions.telnet.TelnetConsole': 0,
    'scrapy.extensions.memusage.MemoryUsage': 0,
    'scrapy.extensions.memdebug.MemoryDebugger': 0,
    'scrapy.extensions.closespider.CloseSpider': 0,
    'scrapy.extensions.feedexport.FeedExporter': 0,
    'scrapy.extensions.logstats.LogStats': 0,
    'scrapy.extensions.spiderstate.SpiderState': 0,
    'scrapy.extensions.throttle.AutoThrottle': 0,
}

A dict containing the extensions available by default in Scrapy, and their orders. This setting contains all stable built-in extensions. Keep in mind that some of them need to be enabled through a setting.

For more information See the extensions user guide and the list of available extensions.

FEED_TEMPDIR

The Feed Temp dir allows you to set a custom folder to save crawler temporary files before uploading with FTP feed storage and Amazon S3.

FTP_PASSIVE_MODE

Default: True

Whether or not to use passive mode when initiating FTP transfers.

FTP_PASSWORD

Default: "guest"

The password to use for FTP connections when there is no "ftp_password" in Request meta.

Note

Paraphrasing RFC 1635, although it is common to use either the password “guest” or one’s e-mail address for anonymous FTP, some FTP servers explicitly ask for the user’s e-mail address and will not allow login with the “guest” password.

FTP_USER

Default: "anonymous"

The username to use for FTP connections when there is no "ftp_user" in Request meta.

ITEM_PIPELINES

Default: {}

A dict containing the item pipelines to use, and their orders. Order values are arbitrary, but it is customary to define them in the 0-1000 range. Lower orders process before higher orders.

Example:

ITEM_PIPELINES = {
    'mybot.pipelines.validate.ValidateMyItem': 300,
    'mybot.pipelines.validate.StoreMyItem': 800,
}

ITEM_PIPELINES_BASE

Default: {}

A dict containing the pipelines enabled by default in Scrapy. You should never modify this setting in your project, modify ITEM_PIPELINES instead.

LOG_ENABLED

Default: True

Whether to enable logging.

LOG_ENCODING

Default: 'utf-8'

The encoding to use for logging.

LOG_FILE

Default: None

File name to use for logging output. If None, standard error will be used.

LOG_FORMAT

Default: '%(asctime)s [%(name)s] %(levelname)s: %(message)s'

String for formatting log messages. Refer to the Python logging documentation for the qwhole list of available placeholders.

LOG_DATEFORMAT

Default: '%Y-%m-%d %H:%M:%S'

String for formatting date/time, expansion of the %(asctime)s placeholder in LOG_FORMAT. Refer to the Python datetime documentation for the whole list of available directives.

LOG_FORMATTER

Default: scrapy.logformatter.LogFormatter

The class to use for formatting log messages for different actions.

LOG_LEVEL

Default: 'DEBUG'

Minimum level to log. Available levels are: CRITICAL, ERROR, WARNING, INFO, DEBUG. For more info see Logging.

LOG_STDOUT

Default: False

If True, all standard output (and error) of your process will be redirected to the log. For example if you print('hello') it will appear in the Scrapy log.

LOG_SHORT_NAMES

Default: False

If True, the logs will just contain the root path. If it is set to False then it displays the component responsible for the log output

LOGSTATS_INTERVAL

Default: 60.0

The interval (in seconds) between each logging printout of the stats by LogStats.

MEMDEBUG_ENABLED

Default: False

Whether to enable memory debugging.

MEMDEBUG_NOTIFY

Default: []

When memory debugging is enabled a memory report will be sent to the specified addresses if this setting is not empty, otherwise the report will be written to the log.

Example:

MEMDEBUG_NOTIFY = ['user@example.com']

MEMUSAGE_ENABLED

Default: True

Scope: scrapy.extensions.memusage

Whether to enable the memory usage extension. This extension keeps track of a peak memory used by the process (it writes it to stats). It can also optionally shutdown the Scrapy process when it exceeds a memory limit (see MEMUSAGE_LIMIT_MB), and notify by email when that happened (see MEMUSAGE_NOTIFY_MAIL).

See Memory usage extension.

MEMUSAGE_LIMIT_MB

Default: 0

Scope: scrapy.extensions.memusage

The maximum amount of memory to allow (in megabytes) before shutting down Scrapy (if MEMUSAGE_ENABLED is True). If zero, no check will be performed.

See Memory usage extension.

MEMUSAGE_CHECK_INTERVAL_SECONDS

New in version 1.1.

Default: 60.0

Scope: scrapy.extensions.memusage

The Memory usage extension checks the current memory usage, versus the limits set by MEMUSAGE_LIMIT_MB and MEMUSAGE_WARNING_MB, at fixed time intervals.

This sets the length of these intervals, in seconds.

See Memory usage extension.

MEMUSAGE_NOTIFY_MAIL

Default: False

Scope: scrapy.extensions.memusage

A list of emails to notify if the memory limit has been reached.

Example:

MEMUSAGE_NOTIFY_MAIL = ['user@example.com']

See Memory usage extension.

MEMUSAGE_WARNING_MB

Default: 0

Scope: scrapy.extensions.memusage

The maximum amount of memory to allow (in megabytes) before sending a warning email notifying about it. If zero, no warning will be produced.

NEWSPIDER_MODULE

Default: ''

Module where to create new spiders using the genspider command.

Example:

NEWSPIDER_MODULE = 'mybot.spiders_dev'

RANDOMIZE_DOWNLOAD_DELAY

Default: True

If enabled, Scrapy will wait a random amount of time (between 0.5 * DOWNLOAD_DELAY and 1.5 * DOWNLOAD_DELAY) while fetching requests from the same website.

This randomization decreases the chance of the crawler being detected (and subsequently blocked) by sites which analyze requests looking for statistically significant similarities in the time between their requests.

The randomization policy is the same used by wget --random-wait option.

If DOWNLOAD_DELAY is zero (default) this option has no effect.

REACTOR_THREADPOOL_MAXSIZE

Default: 10

The maximum limit for Twisted Reactor thread pool size. This is common multi-purpose thread pool used by various Scrapy components. Threaded DNS Resolver, BlockingFeedStorage, S3FilesStore just to name a few. Increase this value if you’re experiencing problems with insufficient blocking IO.

REDIRECT_PRIORITY_ADJUST

Default: +2

Scope: scrapy.downloadermiddlewares.redirect.RedirectMiddleware

Adjust redirect request priority relative to original request:

a positive priority adjust (default) means higher priority.
a negative priority adjust means lower priority.

RETRY_PRIORITY_ADJUST

Default: -1

Scope: scrapy.downloadermiddlewares.retry.RetryMiddleware

Adjust retry request priority relative to original request:

a positive priority adjust means higher priority.
a negative priority adjust (default) means lower priority.

ROBOTSTXT_OBEY

Default: False

Scope: scrapy.downloadermiddlewares.robotstxt

If enabled, Scrapy will respect robots.txt policies. For more information see RobotsTxtMiddleware.

Note

While the default value is False for historical reasons, this option is enabled by default in settings.py file generated by scrapy startproject command.

ROBOTSTXT_PARSER

Default: 'scrapy.robotstxt.ProtegoRobotParser'

The parser backend to use for parsing robots.txt files. For more information see RobotsTxtMiddleware.

ROBOTSTXT_USER_AGENT

Default: None

The user agent string to use for matching in the robots.txt file. If None, the User-Agent header you are sending with the request or the USER_AGENT setting (in that order) will be used for determining the user agent to use in the robots.txt file.

SCHEDULER

Default: 'scrapy.core.scheduler.Scheduler'

The scheduler to use for crawling.

SCHEDULER_DEBUG

Default: False

Setting to True will log debug information about the requests scheduler. This currently logs (only once) if the requests cannot be serialized to disk. Stats counter (scheduler/unserializable) tracks the number of times this happens.

Example entry in logs:

1956-01-31 00:00:00+0800 [scrapy.core.scheduler] ERROR: Unable to serialize request:
<GET http://example.com> - reason: cannot serialize <Request at 0x9a7c7ec>
(type Request)> - no more unserializable requests will be logged
(see 'scheduler/unserializable' stats counter)

SCHEDULER_DISK_QUEUE

Default: 'scrapy.squeues.PickleLifoDiskQueue'

Type of disk queue that will be used by scheduler. Other available types are scrapy.squeues.PickleFifoDiskQueue, scrapy.squeues.MarshalFifoDiskQueue, scrapy.squeues.MarshalLifoDiskQueue.

SCHEDULER_MEMORY_QUEUE

Default: 'scrapy.squeues.LifoMemoryQueue'

Type of in-memory queue used by scheduler. Other available type is: scrapy.squeues.FifoMemoryQueue.

SCHEDULER_PRIORITY_QUEUE

Default: 'scrapy.pqueues.ScrapyPriorityQueue'

Type of priority queue used by the scheduler. Another available type is scrapy.pqueues.DownloaderAwarePriorityQueue. scrapy.pqueues.DownloaderAwarePriorityQueue works better than scrapy.pqueues.ScrapyPriorityQueue when you crawl many different domains in parallel. But currently scrapy.pqueues.DownloaderAwarePriorityQueue does not work together with CONCURRENT_REQUESTS_PER_IP.

SCRAPER_SLOT_MAX_ACTIVE_SIZE

New in version 2.0.

Default: 5_000_000

Soft limit (in bytes) for response data being processed.

While the sum of the sizes of all responses being processed is above this value, Scrapy does not process new requests.

SPIDER_CONTRACTS

Default:: {}

A dict containing the spider contracts enabled in your project, used for testing spiders. For more info see Spiders Contracts.

SPIDER_CONTRACTS_BASE

Default:

{
    'scrapy.contracts.default.UrlContract' : 1,
    'scrapy.contracts.default.ReturnsContract': 2,
    'scrapy.contracts.default.ScrapesContract': 3,
}

A dict containing the Scrapy contracts enabled by default in Scrapy. You should never modify this setting in your project, modify SPIDER_CONTRACTS instead. For more info see Spiders Contracts.

You can disable any of these contracts by assigning None to their class path in SPIDER_CONTRACTS. E.g., to disable the built-in ScrapesContract, place this in your settings.py:

SPIDER_CONTRACTS = {
    'scrapy.contracts.default.ScrapesContract': None,
}

SPIDER_LOADER_CLASS

Default: 'scrapy.spiderloader.SpiderLoader'

The class that will be used for loading spiders, which must implement the SpiderLoader API.

SPIDER_LOADER_WARN_ONLY

New in version 1.3.3.

Default: False

By default, when Scrapy tries to import spider classes from SPIDER_MODULES, it will fail loudly if there is any ImportError exception. But you can choose to silence this exception and turn it into a simple warning by setting SPIDER_LOADER_WARN_ONLY = True.

Note

Some scrapy commands run with this setting to True already (i.e. they will only issue a warning and will not fail) since they do not actually need to load spider classes to work: scrapy runspider, scrapy settings, scrapy startproject, scrapy version.

SPIDER_MIDDLEWARES

Default:: {}

A dict containing the spider middlewares enabled in your project, and their orders. For more info see Activating a spider middleware.

SPIDER_MIDDLEWARES_BASE

Default:

{
    'scrapy.spidermiddlewares.httperror.HttpErrorMiddleware': 50,
    'scrapy.spidermiddlewares.offsite.OffsiteMiddleware': 500,
    'scrapy.spidermiddlewares.referer.RefererMiddleware': 700,
    'scrapy.spidermiddlewares.urllength.UrlLengthMiddleware': 800,
    'scrapy.spidermiddlewares.depth.DepthMiddleware': 900,
}

A dict containing the spider middlewares enabled by default in Scrapy, and their orders. Low orders are closer to the engine, high orders are closer to the spider. For more info see Activating a spider middleware.

SPIDER_MODULES

Default: []

A list of modules where Scrapy will look for spiders.

Example:

SPIDER_MODULES = ['mybot.spiders_prod', 'mybot.spiders_dev']

STATS_CLASS

Default: 'scrapy.statscollectors.MemoryStatsCollector'

The class to use for collecting stats, who must implement the Stats Collector API.

STATS_DUMP

Default: True

Dump the Scrapy stats (to the Scrapy log) once the spider finishes.

For more info see: Stats Collection.

STATSMAILER_RCPTS

Default: [] (empty list)

Send Scrapy stats after spiders finish scraping. See StatsMailer for more info.

TELNETCONSOLE_ENABLED

Default: True

A boolean which specifies if the telnet console will be enabled (provided its extension is also enabled).

TEMPLATES_DIR

Default: templates dir inside scrapy module

The directory where to look for templates when creating new projects with startproject command and new spiders with genspider command.

The project name must not conflict with the name of custom files or directories in the project subdirectory.

TWISTED_REACTOR

New in version 2.0.

Default: None

Import path of a given reactor.

Scrapy will install this reactor if no other reactor is installed yet, such as when the scrapy CLI program is invoked or when using the CrawlerProcess class.

If you are using the CrawlerRunner class, you also need to install the correct reactor manually. You can do that using install_reactor():

scrapy.utils.reactor.``install_reactor(reactor_path)[source]

Installs the reactor with the specified import path.

If a reactor is already installed, install_reactor() has no effect.

CrawlerRunner.__init__ raises Exception if the installed reactor does not match the TWISTED_REACTOR setting; therfore, having top-level reactor imports in project files and imported third-party libraries will make Scrapy raise Exception when it checks which reactor is installed.

In order to use the reactor installed by Scrapy:

import scrapy
from twisted.internet import reactor
class QuotesSpider(scrapy.Spider):
    name = 'quotes'
    def __init__(self, *args, **kwargs):
        self.timeout = int(kwargs.pop('timeout', '60'))
        super(QuotesSpider, self).__init__(*args, **kwargs)
    def start_requests(self):
        reactor.callLater(self.timeout, self.stop)
        urls = ['http://quotes.toscrape.com/page/1']
        for url in urls:
            yield scrapy.Request(url=url, callback=self.parse)
    def parse(self, response):
        for quote in response.css('div.quote'):
            yield {'text': quote.css('span.text::text').get()}
    def stop(self):
        self.crawler.engine.close_spider(self, 'timeout')

which raises Exception, becomes:

import scrapy
class QuotesSpider(scrapy.Spider):
    name = 'quotes'
    def __init__(self, *args, **kwargs):
        self.timeout = int(kwargs.pop('timeout', '60'))
        super(QuotesSpider, self).__init__(*args, **kwargs)
    def start_requests(self):
        from twisted.internet import reactor
        reactor.callLater(self.timeout, self.stop)
        urls = ['http://quotes.toscrape.com/page/1']
        for url in urls:
            yield scrapy.Request(url=url, callback=self.parse)
    def parse(self, response):
        for quote in response.css('div.quote'):
            yield {'text': quote.css('span.text::text').get()}
    def stop(self):
        self.crawler.engine.close_spider(self, 'timeout')

The default value of the TWISTED_REACTOR setting is None, which means that Scrapy will not attempt to install any specific reactor, and the default reactor defined by Twisted for the current platform will be used. This is to maintain backward compatibility and avoid possible problems caused by using a non-default reactor.

For additional information, see Choosing a Reactor and GUI Toolkit Integration.

URLLENGTH_LIMIT

Default: 2083

Scope: spidermiddlewares.urllength

The maximum URL length to allow for crawled URLs. For more information about the default value for this setting see: https://boutell.com/newfaq/misc/urllength.html

USER_AGENT

Default: "Scrapy/VERSION (+https://scrapy.org)"

The default User-Agent to use when crawling, unless overridden. This user agent is also used by RobotsTxtMiddleware if ROBOTSTXT_USER_AGENT setting is None and there is no overridding User-Agent header specified for the request.

Settings documented elsewhere:

The following settings are documented elsewhere, please check each specific case to see how to enable and use them.