Source Code for Module grassyknoll.backend.dictionary.DictCollection

 1  """L{dict} based collection""" 
 2  import cPickle 
 3  import os.path 
 4   
 5  from grassyknoll.collection import Collection 
 6   
 7 -class DictCollection(Collection.Collection): 
 8      """an in-memory collection""" 
 9       
10 -    def __init__(self, data=None): 
11          self.data=data if data is not None else {} 
12       
13 -    def __len__(self): 
14          return len(self.data) 
15       
16      @Collection.addMetaData 
17 -    def list(self): 
18          return Collection.CollectionIds(self.data.keys()) 
19   
20      @Collection.addMetaData 
21 -    def create(self, docs): 
22          for doc in docs: 
23              self.data[doc.id]=doc 
24          return Collection.CollectionIds([doc.id for doc in docs])     
25       
26      @Collection.addMetaData 
27 -    def delete(self, ids): 
28          for uid in ids: 
29              self.data.pop(uid, None) 
30          return Collection.CollectionIds(ids) 
31       
32      @Collection.addMetaData 
33 -    def retrieve(self, ids, fields=None):         
34          results=[] 
35          for uid in ids: 
36              doc=self.data.get(uid) 
37              if doc is not None: 
38                  assert isinstance(doc, Collection.CollectionDocument) 
39                  if fields is None: 
40                      res=Collection.CollectionResult(doc) 
41                  else: 
42                      if '__id__' not in fields: fields+=('__id__',) 
43                      res=Collection.CollectionResult(dict((k, v) for k, v 
44                                                           in doc.iteritems() 
45                                                           if k in fields)) 
46                  results.append(res) 
47           
48          return Collection.CollectionResultSet(results) 
49   
50  # no point testing this 
51 -class PersistentDictCollection(DictCollection): #pragma: no cover 
52      """a L{DictCollection} that saves to a pickle""" 
53       
54 -    def __init__(self, fname): 
55          super(PersistentDictCollection, self).__init__() 
56          self.fname=fname 
57          if os.path.exists(fname): 
58              self.data=cPickle.load(file(fname, 'r')) 
59              assert isinstance(self.data, dict) 
60   
61 -    def close(self): 
62          cPickle.dump(self.data, file(self.fname, 'w'), -1) 
63