NIFI-4826 Fixed azure.blobname in ListAzureBlobStorage

[zenfenan]

• azure.blobname now has the value returned by CloudBlob.getName().
• Tested for blobs located in a multiple hierarchy directory structure by connecting ListAzureBlobStorage with FetchAzureBlobStorage with the latter processor's "Blob" property set to ${azure.blobname}
• Also fixed filename which was previously having timestamp with the blob's partial name.

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[pvillard31]

I'm a bit worried about this change. It's going to change the value of a core attribute (filename) that could break the behavior of existing workflows. I'd rather user another attribute name if we still want to have an attribute for entity.getName(). Thoughts?

[zenfenan]

I dint use filename just because to find a use for entity.getName() The filename attribute for ListAzureBlobStorage as of 1.5.0 has a large number as its name, much like the filenames of flowfiles generated by GenerateFlowFiles processor. The change here is intended to provide a meaningful filename i.e. the actual name of the blob.

My assumption was that people would either be updating the filename using UpdateAttribute/ExecuteScript (parsing the azure.primaryUri and taking the file name) or simply ignoring the filename altogether. In that case, this change won't affect, right? For ex: If people are overwriting filename attribute, whatever this contribution produces as a filename will still be overwritten ( I am again going with the assumption that they would either be parsing the filename from the azure.primaryUri attribute since that's the only attribute that provides us the blob name). If they aren't touching the filename attribute, then this would just produce a meaningful filename. Hope you understood what I'm trying to say.

[pvillard31]

You're right. I actually completely missed the fact that this change is for a processor with no input relationship... Disregard my comment.

[pvillard31]

LGTM, merging to master, thanks @zenfenan