import os
from twisted.python.failure import Failure
from twisted.internet import defer,reactor,protocol,error
from twisted.protocols.basic import LineOnlyReceiver
class FakeTransport:
disconnecting = False
class BuildmasterTimeoutError(Exception):
pass
class BuildslaveTimeoutError(Exception):
pass
class ReconfigError(Exception):
pass
class BuildSlaveDetectedError(Exception):
pass
class TailProcess(protocol.ProcessProtocol):
def outReceived(self, data):
self.lw.dataReceived(data)
def errReceived(self, data):
print "ERR: '%s'" % (data,)
class LogWatcher(LineOnlyReceiver):
POLL_INTERVAL = 0.1
TIMEOUT_DELAY = 10.0
delimiter = os.linesep
def __init__(self, logfile):
self.logfile = logfile
self.in_reconfig = False
self.transport = FakeTransport()
self.pp = TailProcess()
self.pp.lw = self
self.processtype = "buildmaster"
self.timer = None
def start(self):
# If the log file doesn't exist, create it now.
if not os.path.exists(self.logfile):
open(self.logfile, 'a').close()
# return a Deferred that fires when the reconfig process has
# finished. It errbacks with TimeoutError if the finish line has not
# been seen within 10 seconds, and with ReconfigError if the error
# line was seen. If the logfile could not be opened, it errbacks with
# an IOError.
self.p = reactor.spawnProcess(self.pp, "/usr/bin/tail",
("tail", "-f", "-n", "0", self.logfile),
env=os.environ,
)
self.running = True
d = defer.maybeDeferred(self._start)
return d
def _start(self):
self.d = defer.Deferred()
self.timer = reactor.callLater(self.TIMEOUT_DELAY, self.timeout)
return self.d
def timeout(self):
self.timer = None
if self.processtype == "buildmaster":
e = BuildmasterTimeoutError()
else:
e = BuildslaveTimeoutError()
self.finished(Failure(e))
def finished(self, results):
try:
self.p.signalProcess("KILL")
except error.ProcessExitedAlready:
pass
if self.timer:
self.timer.cancel()
self.timer = None
self.running = False
self.in_reconfig = False
self.d.callback(results)
def lineReceived(self, line):
if not self.running:
return
if "Log opened." in line:
self.in_reconfig = True
if "loading configuration from" in line:
self.in_reconfig = True
if "Creating BuildSlave" in line:
self.processtype = "buildslave"
if self.in_reconfig:
print line
if "message from master: attached" in line:
return self.finished("buildslave")
if "I will keep using the previous config file" in line:
return self.finished(Failure(ReconfigError()))
if "configuration update complete" in line:
return self.finished("buildmaster")
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