buildbot/locks.py

   1 # -*- test-case-name: buildbot.test.test_locks -*-
   2
   3 from twisted.python import log
   4 from twisted.internet import reactor, defer
   5 from buildbot import util
   6
   7 class BaseLock:
   8     owner = None
   9     description = "<BaseLock>"
  10
  11     def __init__(self, name):
  12         self.name = name
  13         self.waiting = []
  14
  15     def __repr__(self):
  16         return self.description
  17
  18     def isAvailable(self):
  19         log.msg("%s isAvailable: self.owner=%s" % (self, self.owner))
  20         return not self.owner
  21
  22     def claim(self, owner):
  23         log.msg("%s claim(%s)" % (self, owner))
  24         assert owner is not None
  25         self.owner = owner
  26         log.msg(" %s is claimed" % (self,))
  27
  28     def release(self, owner):
  29         log.msg("%s release(%s)" % (self, owner))
  30         assert owner is self.owner
  31         self.owner = None
  32         reactor.callLater(0, self.nowAvailable)
  33
  34     def waitUntilAvailable(self, owner):
  35         log.msg("%s waitUntilAvailable(%s)" % (self, owner))
  36         assert self.owner, "You aren't supposed to call this on a free Lock"
  37         d = defer.Deferred()
  38         self.waiting.append((d, owner))
  39         return d
  40
  41     def nowAvailable(self):
  42         log.msg("%s nowAvailable" % self)
  43         assert not self.owner
  44         if not self.waiting:
  45             return
  46         d,owner = self.waiting.pop(0)
  47         d.callback(self)
  48
  49 class RealMasterLock(BaseLock):
  50     def __init__(self, name):
  51         BaseLock.__init__(self, name)
  52         self.description = "<MasterLock(%s)>" % (name,)
  53
  54     def getLock(self, slave):
  55         return self
  56
  57 class RealSlaveLock(BaseLock):
  58     def __init__(self, name):
  59         BaseLock.__init__(self, name)
  60         self.description = "<SlaveLock(%s)>" % (name,)
  61         self.locks = {}
  62
  63     def getLock(self, slavebuilder):
  64         slavename = slavebuilder.slave.slavename
  65         if not self.locks.has_key(slavename):
  66             lock = self.locks[slavename] = BaseLock(self.name)
  67             lock.description = "<SlaveLock(%s)[%s] %d>" % (self.name,
  68                                                             slavename,
  69                                                             id(lock))
  70             self.locks[slavename] = lock
  71         return self.locks[slavename]
  72
  73
  74 # master.cfg should only reference the following MasterLock and SlaveLock
  75 # classes. They are identifiers that will be turned into real Locks later,
  76 # via the BotMaster.getLockByID method.
  77
  78 class MasterLock(util.ComparableMixin):
  79     compare_attrs = ['name']
  80     lockClass = RealMasterLock
  81     def __init__(self, name):
  82         self.name = name
  83
  84 class SlaveLock(util.ComparableMixin):
  85     compare_attrs = ['name']
  86     lockClass = RealSlaveLock
  87     def __init__(self, name):
  88         self.name = name
  89