Source Code for Module Ganga.Core.JobRepositoryXML.Counter

 1  import pickle,os.path 
 2   
 3 -class Counter: 
 4      """ Simple persistent counter. """ 
 5       
 6 -    def __init__(self,dir): 
 7          """Initialize the counter file in dir directory""" 
 8          self.dir = dir 
 9          self.cntfn = os.path.join(self.dir,'cnt') 
10          #self.lockfn = os.path.join(self.dir,'lock') #FIXME: locking support 
11   
12          try: 
13              self.cnt = pickle.load(file(self.cntfn)) 
14          except IOError,x: 
15              import errno 
16              if x.errno == errno.ENOENT: 
17                  self.cnt = 0 
18              else: 
19                  raise 
20   
21 -    def make_new_ids(self,n): 
22          """Generate n new job ids""" 
23          ids = range(self.cnt,self.cnt+n) 
24          self.cnt += n 
25          pickle.dump(self.cnt,file(self.cntfn,'w')) 
26          return ids 
27   
28 -    def subtract(self): 
29          self.cnt -= 1 
30          pickle.dump(self.cnt,file(self.cntfn,'w')) 
31