scrapy/scrapy/service.py

89 lines
3.2 KiB
Python

import sys, os
from twisted.python import log
from twisted.internet import reactor, defer, protocol, error
from twisted.application.service import Service
from scrapy.utils.py26 import cpu_count
from scrapy.conf import settings
class ScrapyService(Service):
def startService(self):
reactor.callWhenRunning(self.spawn_processes)
def spawn_processes(self):
for settings_module, count in settings['PROJECTS'].items():
for i in range(count or cpu_count()):
self.spawn_process(settings_module, i)
def spawn_process(self, settings_module, position):
args = [sys.executable, '-m', 'scrapy.cmdline', 'start']
env = os.environ.copy()
botname = self.get_bot_name(settings_module)
logfile = self.get_log_file(settings_module, position)
env['SCRAPY_SETTINGS_MODULE'] = settings_module
env['SCRAPY_LOG_FILE'] = logfile
pp = ScrapyProcessProtocol(botname, settings_module, logfile)
pp.deferred.addCallback(lambda _: reactor.callLater(5, \
self.spawn_process, settings_module, position))
reactor.spawnProcess(pp, sys.executable, args=args, env=env)
def get_log_file(self, settings_module, position):
botname = self.get_bot_name(settings_module)
basename = "%s-%s" % (botname, position) if position else botname
return os.path.join(settings['LOG_DIR'], "%s.log" % basename)
def get_bot_name(self, settings_module):
mod = __import__(settings_module, {}, {}, [''], -1)
return mod.BOT_NAME
class ScrapyProcessProtocol(protocol.ProcessProtocol):
TAIL_LINES = 100
def __init__(self, botname, settings_module, logfile):
self.botname = botname
self.settings_module = settings_module
self.logfile = logfile
self.pid = None
self.deferred = defer.Deferred()
self.outdata = ''
self.errdata = ''
def outReceived(self, data):
self.outdata = self._tail(self.outdata + data)
def errReceived(self, data):
self.errdata = self._tail(self.errdata + data)
def connectionMade(self):
self.pid = self.transport.pid
log.msg("Crawler %r started: pid=%r settings=%r log=%r" % \
(self.botname, self.pid, self.settings_module, self.logfile))
def processEnded(self, status):
if isinstance(status.value, error.ProcessDone):
msg = "Crawler %r finished: pid=%r settings=%r log=%r" % \
(self.botname, self.pid, self.settings_module, self.logfile)
else:
msg = "Crawler %r died: exitstatus=%r pid=%r settings=%r log=%r" % \
(self.botname, status.value.exitCode, self.pid, self.settings_module, \
self.logfile)
self._log_ended(msg)
self.deferred.callback(self)
def _log_ended(self, msg):
tolog = [msg]
if self.outdata:
tolog += [">>> stdout (last %d lines) <<<" % self.TAIL_LINES]
tolog += [self.outdata]
if self.errdata:
tolog += [">>> stderr (last %d lines) <<<" % self.TAIL_LINES]
tolog += [self.errdata]
log.msg(os.linesep.join(tolog))
def _tail(self, data, lines=TAIL_LINES):
return os.linesep.join(data.split(os.linesep)[-lines:])