[LIBCLOUD-986] List / Iterate container with prefix for Azure Blob service (This support exists in the other drivers already)

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Component/s: Storage
• Assignee: Unassigned
• Reporter: Joshua Hawkinson
• Created: 16/Mar/18 00:50
• Updated: 30/Mar/18 15:35
• Resolved: 30/Mar/18 15:35

Description

While testing out the libcloud storage abstraction I've come across a curious omission in driver support. It seems that for many drivers there is additional support for the list_container_objects() and iterate_container_objects() to support a prefix (or ex_prefix). 

This functionality is not present in the Azure driver for some reason.   I've gone and checked the list_blobs API and it also supports this functionality as seen here:

https://docs.microsoft.com/en-us/rest/api/storageservices/list-blobs

 

I've attempted a quick and dirty patch that seems to work as well.

azure_blobs.py Line 384

-    def iterate_container_objects(self, container):
+    def iterate_container_objects(self, container, ex_prefix=None):
        """
        @inherits: :class:`StorageDriver.iterate_container_objects`
        """
        params = {'restype': 'container',
                  'comp': 'list',
+                  'prefix': ex_prefix,
                  'maxresults': RESPONSES_PER_REQUEST,
                  'include': 'metadata'}

Line 419 (Add new function)
    def list_container_objects(self, container, ex_prefix=None):
        """
        Return a list of objects for the given container.
    
        :param container: Container instance.
        :type container: :class:`Container`
    
        :param ex_prefix: Only return objects starting with ex_prefix
        :type ex_prefix: ``str``
    
        :return: A list of Object instances.
        :rtype: ``list`` of :class:`Object`
        """
        return list(self.iterate_container_objects(container,
                                                   ex_prefix=ex_prefix))
    
 

 
I've just worked around this at a higher level for now. There isn't any urgency on my end,  but it would be nice if the abstraction was more consistent so I could remove the workaround code.

Issue Links

• links to: GitHub Pull Request #1193