twisted 模拟scrapy调度循环
"""
模拟scrapy调度循环
"""
from ori_test import pr_type
import logging
import time
from twisted.internet import defer, task, reactor
from scrapy.utils.reactor import CallLaterOnce
log = logging.getLogger(__name__)
logger_m = log
class Slot(object):
def __init__(self, start_requests, nextcall):
self.start_requests = iter(start_requests)
self.nextcall = nextcall
self.heartbeat = task.LoopingCall(nextcall.schedule)
class Engine():
@defer.inlineCallbacks
def open_spider(self, spider, start_requests):
nextcall = CallLaterOnce(self._next_request, spider)
#start_requests = yield self.scraper.spidermw.process_start_requests(start_requests, spider)
slot = Slot(start_requests, nextcall)
self.slot = slot
self.spider = spider
yield 8
slot.nextcall.schedule()
slot.heartbeat.start(5)
def _next_request(self, spider):
print('next_request')
slot = self.slot
if not slot:
return
try:
v = next(slot.start_requests)
except StopIteration:
slot.start_requests = None
except Exception:
slot.start_requests = None
else:
def task_print(k):
#k = next(slot.start_requests)
d = defer.Deferred()
reactor.callLater(0, d.callback, k)
return d
d = task_print(v)
d.addCallback(lambda x: print('d is done', x))
d.addErrback(lambda x: print('d is not done'))
d.addCallback(self._next_request)
d.addErrback(lambda x: print('d is error'))
class Spider():
def __init__(self):
pass
self._before_start()
def start_requests(self):
logger_m.info('start spider the first page!')
# USER_AGENT = 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36'
for x in range(1000):
#time.sleep(3)
print('from spider yield', x )
yield x
#print(x)
# req = scrapy.Request(url='https://httpbin.org/ip', dont_filter=True)
yield 8888
def _before_start(self):
# 注册爬虫,信息内容为{spider_id, time()}
def spider_alive():
print('from looptask:spider alive')
# print(res)
pass
# 添加到定时任务,定时声明爬虫生死
# twisted 任务
looptask = task.LoopingCall(spider_alive)
looptask.start(5, now=True)
#looptask.start(60, now=True)
spider = Spider()
s_r = spider.start_requests()
pr_type(s_r)
s_r = iter(s_r)
pr_type(s_r)
a = Engine()
a.open_spider(spider, s_r)
reactor.run()
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