Source Code for Package amplee.storage

  1  # -*- coding: utf-8 -*- 
  2  __docformat__ = 'epytext en' 
  3   
  4  __all__ = ['Storage', 'StorageResourceInfo'] 
  5   
  6 -class StorageResourceInfo(object): 
  7 -    def __init__(self, name=None, key=None, collection_name=None): 
  8          """ 
  9          Wraps in a neutral object any storage implementation 
 10          mechanism to identify and access a resource. 
 11   
 12          @type name: string or unicode 
 13          @param name: name of the resource. 
 14   
 15          @type key: object 
 16          @param key: per-storage class object used to identify and access the resource 
 17           in that storage. 
 18   
 19          @type collection_name: string or unicode 
 20          @param collection_name: name of the collection to which the resource belongs 
 21          """ 
 22          self.name = name 
 23          self.key = key 
 24          self.collection_name = collection_name 
 25   
 26 -class Storage(object): 
 27      """Base storage class. Should not be instanciated""" 
 28       
 29 -    def shutdown(self): 
 30          """Shutdown the underlying storage connections""" 
 31          raise NotImplemented() 
 32   
 33 -    def create_container(self, name): 
 34          """ 
 35          Creates a container within a storage if it doesn't already exist. 
 36          A container means whatever is meaningful for the subclass storage. 
 37          A directory in the filesystem storage, a OBTree in the ZODB 
 38          storage, a table in a database storage. 
 39   
 40          @type name: string 
 41          @param name: name of the container 
 42   
 43          @rtype: object 
 44          @return: the subclass may or may not return an object 
 45           upon the creation of the container 
 46          """ 
 47          raise NotImplemented() 
 48   
 49 -    def info(self, collection_name, resource_name): 
 50          """ 
 51          Returns an object allowing an access to the resource within the storage. 
 52   
 53          @type collection_name: string 
 54          @param collection_name: name of the collection 
 55   
 56          @type resource_name: string 
 57          @param resource_name: name of the resource 
 58   
 59          @rtype: L{StorageResourceInfo} or subclass 
 60          @return: an object representing the resource within the storage 
 61          """ 
 62          raise NotImplemented() 
 63       
 64 -    def get_content(self, info, *args, **kwargs): 
 65          """ 
 66          Returns the content of a resource 
 67   
 68          @type info: L{StorageResourceInfo} or subclass 
 69          @param info: object representing the resource in the storage 
 70           
 71          @rtype: object 
 72          @return: content of the resource 
 73          """ 
 74          raise NotImplemented() 
 75       
 76 -    def get_meta_data(self, info, *args, **kwargs): 
 77          """ 
 78          Returns the atom entry representing the resource 
 79   
 80          @type info: L{StorageResourceInfo} or subclass 
 81          @param info: object representing the resource in the storage 
 82           
 83          @rtype: string 
 84          @return: content of the atom entry 
 85          """ 
 86          raise NotImplemented() 
 87       
 88 -    def put_content(self, info, content, *args, **kwargs): 
 89          """ 
 90          Puts the content of a resource 
 91   
 92          @type info: L{StorageResourceInfo} or subclass 
 93          @param info: object representing the resource in the storage 
 94   
 95          @type content: string or fileobject 
 96          @param content: content to store within the storage 
 97          """ 
 98          raise NotImplemented() 
 99       
100 -    def put_meta_data(self, info, content, *args, **kwargs): 
101          """ 
102          Sets the atom entry of a resource 
103   
104          @type info: L{StorageResourceInfo} or subclass 
105          @param info: object representing the resource in the storage 
106   
107          @type content: string or fileobject 
108          @param content: content to store within the storage 
109          """ 
110          raise NotImplemented() 
111       
112 -    def remove_content(self, info, *args, **kwargs): 
113          """ 
114          Deletes a resource from the storage. 
115   
116          @type info: L{StorageResourceInfo} or subclass 
117          @param info: object representing the resource in the storage 
118          """ 
119          raise NotImplemented() 
120       
121 -    def remove_meta_data(self, info, *args, **kwargs): 
122          """ 
123          Delete the atom entry from the storage 
124   
125          @type info: L{StorageResourceInfo} or subclass 
126          @param info: object representing the resource in the storage 
127          """ 
128          raise NotImplemented 
129   
130 -    def persist(self, *args, **kwargs): 
131          """ 
132          Persists the operations made 
133          """ 
134          raise NotImplemented() 
135   
136 -    def exists(self, info): 
137          """ 
138          Checks whether or not C{info.key} is valid for the storage 
139           
140          @type info: L{StorageResourceInfo} or subclass 
141          @param info: object representing the resource in the storage 
142   
143          @rtype: bool 
144          @return: C{True} if the test succeeds, C{False} otherwise. 
145          """ 
146          raise NotImplemented() 
147       
148 -    def ls(self, collection_name_or_id, ext=None): 
149          """ 
150          Returns existing members as a dictionnary of the form 
151          members[resource_name] = StorageResourceInfo instance. 
152   
153          @type collection_name_or_id: string 
154          @param collection_name_or_id: name of the collection to use for the listing 
155   
156          @type ext: string or C{NoneType} 
157          @param ext: extension to filter the members with during the listing 
158   
159          @rtype: dict 
160          @return: a dictionnary of existing members, their identifier and a 
161           L{StorageResourceInfo} instance representing the resource. 
162          """ 
163          raise NotImplemented() 
164   
165 -    def ils(self, collection_name_or_id, ext=None): 
166          """ 
167          Yields existing members as a tuple of the form 
168          C{(resource_name, StorageResourceInfo instance)} 
169   
170          @type collection_name_or_id: string 
171          @param collection_name_or_id: name of the collection to use for the listing 
172   
173          @type ext: string or C{NoneType} 
174          @param ext: extension to filter the members with during the listing 
175   
176          @rtype: tuple 
177          @return: existing members, their identifier and a 
178           L{StorageResourceInfo} instance representing the resource. 
179          """ 
180          raise NotImplemented() 
181