scrapy setting配置及说明

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

{
    'scrapy.downloadermiddlewares.robotstxt.RobotsTxtMiddleware': 100,
    'scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware': 300,
    'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware': 350,
    'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware': 400,
    'scrapy.downloadermiddlewares.retry.RetryMiddleware': 500,
    'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware': 550,
    '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.chunked.ChunkedTransferMiddleware': 830,
    'scrapy.downloadermiddlewares.stats.DownloaderStats': 850,
    'scrapy.downloadermiddlewares.httpcache.HttpCacheMiddleware': 900,
}

{
    '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',
}

{
    'scrapy.extensions.corestats.CoreStats': 0,
    'scrapy.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,
}

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

{
    '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,
}

# -*- coding: utf-8 -*-
# Scrapy settings for companyNews project
#
# For simplicity, this file contains only settings considered important or
# commonly used. You can find more settings consulting the documentation:
#
#     http://doc.scrapy.org/en/latest/topics/settings.html
#     http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
#     http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html
from DBSetting import host_redis,port_redis,db_redis,password_redis


#它是一种可以用于构建用户代理机器人的名称,默认值:'scrapybot'
BOT_NAME = 'companyNews'
# 它是一种含有蜘蛛其中Scrapy将寻找模块列表,默认值： []
SPIDER_MODULES = ['companyNews.spiders']
# 默认: '',使用 genspider 命令创建新spider的模块。
NEWSPIDER_MODULE = 'companyNews.spiders'
#-----------------------日志文件配置-----------------------------------
# 默认: True,是否启用logging。
# LOG_ENABLED=True
# 默认: 'utf-8',logging使用的编码。
# LOG_ENCODING='utf-8'
# 它是利用它的日志信息可以被格式化的字符串。默认值：'%(asctime)s [%(name)s] %(levelname)s: %(message)s'
# LOG_FORMAT='%(asctime)s [%(name)s] %(levelname)s: %(message)s'
# 它是利用它的日期/时间可以格式化字符串。默认值： '%Y-%m-%d %H:%M:%S'
# LOG_DATEFORMAT='%Y-%m-%d %H:%M:%S'
#日志文件名
#LOG_FILE = "dg.log"
#日志文件级别,默认值：“DEBUG”,log的最低级别。可选的级别有: CRITICAL、 ERROR、WARNING、INFO、DEBUG 。
LOG_LEVEL = 'WARNING'
# -----------------------------robots协议---------------------------------------------
# Obey robots.txt rules
# robots.txt 是遵循 Robot协议 的一个文件，它保存在网站的服务器中，它的作用是，告诉搜索引擎爬虫，
# 本网站哪些目录下的网页 不希望 你进行爬取收录。在Scrapy启动后，会在第一时间访问网站的 robots.txt 文件，
# 然后决定该网站的爬取范围。
# ROBOTSTXT_OBEY = True

# 对于失败的HTTP请求(如超时)进行重试会降低爬取效率，当爬取目标基数很大时，舍弃部分数据不影响大局，提高效率
RETRY_ENABLED = False
#请求下载超时时间，默认180秒
DOWNLOAD_TIMEOUT=20
# 这是响应的下载器下载的最大尺寸，默认值：1073741824 (1024MB)
# DOWNLOAD_MAXSIZE=1073741824
# 它定义为响应下载警告的大小，默认值：33554432 (32MB)
# DOWNLOAD_WARNSIZE=33554432
# ------------------------全局并发数的一些配置:-------------------------------
# Configure maximum concurrent requests performed by Scrapy (default: 16)
# 默认 Request 并发数：16
# CONCURRENT_REQUESTS = 32
# 默认 Item 并发数：100
# CONCURRENT_ITEMS = 100
# The download delay setting will honor only one of:
# 默认每个域名的并发数：8
#CONCURRENT_REQUESTS_PER_DOMAIN = 16
# 每个IP的最大并发数：0表示忽略
# CONCURRENT_REQUESTS_PER_IP = 0

# Configure a delay for requests for the same website (default: 0)
# See http://scrapy.readthedocs.org/en/latest/topics/settings.html#download-delay
# See also autothrottle settings and docs
#DOWNLOAD_DELAY 会影响 CONCURRENT_REQUESTS，不能使并发显现出来,设置下载延迟
#DOWNLOAD_DELAY = 3

# Disable cookies (enabled by default)
#禁用cookies,有些站点会从cookies中判断是否为爬虫
# COOKIES_ENABLED = True
# COOKIES_DEBUG = True

# Crawl responsibly by identifying yourself (and your website) on the user-agent
# 它定义了在抓取网站所使用的用户代理，默认值：“Scrapy / VERSION“
#USER_AGENT = ' (+http://www.yourdomain.com)'

# Override the default request headers:
DEFAULT_REQUEST_HEADERS = {
  'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
  'Accept-Language': 'en',
}
# Enable or disable spider middlewares
# See http://scrapy.readthedocs.org/en/latest/topics/spider-middleware.html
SPIDER_MIDDLEWARES = {
    'companyNews.middlewares.UserAgentmiddleware': 401,
    'companyNews.middlewares.ProxyMiddleware':426,
}
# Enable or disable downloader middlewares
# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html
DOWNLOADER_MIDDLEWARES = {
    'companyNews.middlewares.UserAgentmiddleware': 400,
    'companyNews.middlewares.ProxyMiddleware':425,
    # 'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware':423,
     # 'companyNews.middlewares.CookieMiddleware': 700,
}
MYEXT_ENABLED=True      # 开启扩展
IDLE_NUMBER=12           # 配置空闲持续时间单位为 360个 ，一个时间单位为5s
# Enable or disable extensions
# See http://scrapy.readthedocs.org/en/latest/topics/extensions.html
# 在 EXTENSIONS 配置，激活扩展
EXTENSIONS = {
    # 'scrapy.extensions.telnet.TelnetConsole': None,
    'companyNews.extensions.RedisSpiderSmartIdleClosedExensions': 500,
}
# Configure item pipelines
# See http://scrapy.readthedocs.org/en/latest/topics/item-pipeline.html
# 注意:自定义pipeline的优先级需高于Redispipeline,因为RedisPipeline不会返回item,
# 所以如果RedisPipeline优先级高于自定义pipeline,那么自定义pipeline无法获取到item
ITEM_PIPELINES = {
     #将清除的项目在redis进行处理，# 将RedisPipeline注册到pipeline组件中(这样才能将数据存入Redis)
    # 'scrapy_redis.pipelines.RedisPipeline': 400,
    'companyNews.pipelines.companyNewsPipeline': 300,# 自定义pipeline视情况选择性注册(可选)
}
# Enable and configure HTTP caching (disabled by default)
# See http://scrapy.readthedocs.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings
# ----------------scrapy默认已经自带了缓存，配置如下-----------------
# 打开缓存
#HTTPCACHE_ENABLED = True
# 设置缓存过期时间（单位：秒）
#HTTPCACHE_EXPIRATION_SECS = 0
# 缓存路径(默认为：.scrapy/httpcache)
#HTTPCACHE_DIR = 'httpcache'
# 忽略的状态码
#HTTPCACHE_IGNORE_HTTP_CODES = []
# HTTPERROR_ALLOWED_CODES = [302, 301]
# 缓存模式(文件缓存)
#HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage'

#-----------------Scrapy-Redis分布式爬虫相关设置如下--------------------------
# Enables scheduling storing requests queue in redis.
#启用Redis调度存储请求队列，使用Scrapy-Redis的调度器,不再使用scrapy的调度器
SCHEDULER = "scrapy_redis.scheduler.Scheduler"

# Ensure all spiders share same duplicates filter through redis.
#确保所有的爬虫通过Redis去重，使用Scrapy-Redis的去重组件,不再使用scrapy的去重组件
DUPEFILTER_CLASS = "scrapy_redis.dupefilter.RFPDupeFilter"

# 默认请求序列化使用的是pickle 但是我们可以更改为其他类似的。PS：这玩意儿2.X的可以用。3.X的不能用
# SCHEDULER_SERIALIZER = "scrapy_redis.picklecompat"

# 使用优先级调度请求队列 （默认使用），
# 使用Scrapy-Redis的从请求集合中取出请求的方式,三种方式择其一即可:
# 分别按(1)请求的优先级/(2)队列FIFO/(先进先出)(3)栈FILO 取出请求（先进后出）
# SCHEDULER_QUEUE_CLASS = 'scrapy_redis.queue.PriorityQueue'
# 可选用的其它队列
SCHEDULER_QUEUE_CLASS = 'scrapy_redis.queue.FifoQueue'
# SCHEDULER_QUEUE_CLASS = 'scrapy_redis.queue.LifoQueue'

# Don't cleanup redis queues, allows to pause/resume crawls.
#不清除Redis队列、这样可以暂停/恢复 爬取，
# 允许暂停,redis请求记录不会丢失(重启爬虫不会重头爬取已爬过的页面)
#SCHEDULER_PERSIST = True

#----------------------redis的地址配置-------------------------------------
# Specify the full Redis URL for connecting (optional).
# If set, this takes precedence over the REDIS_HOST and REDIS_PORT settings.
# 指定用于连接redis的URL（可选）
# 如果设置此项，则此项优先级高于设置的REDIS_HOST 和 REDIS_PORT
# REDIS_URL = 'redis://root:密码@主机ＩＰ:端口'
# REDIS_URL = 'redis://root:123456@192.168.8.30:6379'
REDIS_URL = 'redis://root:%s@%s:%s'%(password_redis,host_redis,port_redis)
# 自定义的redis参数（连接超时之类的）
REDIS_PARAMS={'db': db_redis}
# Specify the host and port to use when connecting to Redis (optional).
# 指定连接到redis时使用的端口和地址（可选）
#REDIS_HOST = '127.0.0.1'
#REDIS_PORT = 6379
#REDIS_PASS = '19940225'

#-----------------------------------------暂时用不到-------------------------------------------------------
# 它定义了将被允许抓取的网址的长度为URL的最大极限，默认值：2083
# URLLENGTH_LIMIT=2083
# 爬取网站最大允许的深度(depth)值,默认值0。如果为0，则没有限制
# DEPTH_LIMIT = 3
# 整数值。用于根据深度调整request优先级。如果为0，则不根据深度进行优先级调整。
# DEPTH_PRIORITY=3

# 最大空闲时间防止分布式爬虫因为等待而关闭
# 这只有当上面设置的队列类是SpiderQueue或SpiderStack时才有效
# 并且当您的蜘蛛首次启动时，也可能会阻止同一时间启动（由于队列为空）
# SCHEDULER_IDLE_BEFORE_CLOSE = 10

# 序列化项目管道作为redis Key存储
# REDIS_ITEMS_KEY = '%(spider)s:items'

# 默认使用ScrapyJSONEncoder进行项目序列化
# You can use any importable path to a callable object.
# REDIS_ITEMS_SERIALIZER = 'json.dumps'

# 自定义redis客户端类
# REDIS_PARAMS['redis_cls'] = 'myproject.RedisClient'

# 如果为True，则使用redis的'spop'进行操作。
# 如果需要避免起始网址列表出现重复，这个选项非常有用。开启此选项urls必须通过sadd添加，否则会出现类型错误。
# REDIS_START_URLS_AS_SET = False

# RedisSpider和RedisCrawlSpider默认 start_usls 键
# REDIS_START_URLS_KEY = '%(name)s:start_urls'

# 设置redis使用utf-8之外的编码
# REDIS_ENCODING = 'latin1'

# Disable Telnet Console (enabled by default)
# 它定义是否启用telnetconsole,默认值：True
#TELNETCONSOLE_ENABLED = False

# Enable and configure the AutoThrottle extension (disabled by default)
# See http://doc.scrapy.org/en/latest/topics/autothrottle.html
#AUTOTHROTTLE_ENABLED = True
# The initial download delay
# 开始下载时限速并延迟时间
#AUTOTHROTTLE_START_DELAY = 5
# The maximum download delay to be set in case of high latencies
#高并发请求时最大延迟时间
#AUTOTHROTTLE_MAX_DELAY = 60
# The average number of requests Scrapy should be sending in parallel to
# each remote server
#AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0
# Enable showing throttling stats for every response received:
#AUTOTHROTTLE_DEBUG = False

# REDIRECT_ENABLED = False