Subject: [CDNi] CDNI Logging : access to CDNI Logging File once it is moved from Subscription to Archive in the Logging Feed

From: "Francois Le Faucheur (flefauch)" <[email-masked]>
Date: Fri, 27 Sep 2013 13:15:17 +0000

Folks,

[as a co-author]

I'd like input on one of the very remaining open items in cdni-logging.

For memory, the CDNI Logging Feed allows a dCDN to advertise to the uCDN which CDNI Logging Files can be retrieved by the uCDN from the dCDN.
It is structured as an Archived ATOM feed, meaning that a sliding window of currently available CDNI Logging files is advertised in a "Subscription" document, and then, over time, the older Logging Files are moved to an "Archive" document and new Logging Files appear in the Subscription document.

There is currently an editor's note asking a question about what should happen once a Logging File has been moved to an "archive":
"
  [Editor's note: if a given Logging file is moved away from
   subscription document to an archive document, do we agree it may no
   longer be accessible to uCDN?]
"
I personally agree that the Logging File need not be made available for download once it has moved away from the Subscripton document to the Archive document. My rationale is that:
	* this is precisely the point of the Subscription document i.e. to indicate which files are currently downloadable and the server-side is then responsible for ensuring it can serve these files (ie it has to retain them and be ready to serve them). 
	* it is not reasonable to expect that the server-side will make old Logging Files accessible forever
	* if the client-side wants to have a large window of time to pull Logging Files, then it needs to agree with the server-side and this period will be used as the retention period in the subscripton file. 

Please let us know if you disagree/agree with that, so we can address that in the next rev (this has not been addressed in -06 posted today).

For memory, I think the current text already implies the above:
"
The server-side implementation MUST respond to any valid pull request
   by a client-side implementation for a CDNI Logging File published by
   the server-side in the subscription document of the CDNI Logging
   Feed. 
"
If we agree with the position above, we could also tweak the text to say that the server-side MUST respond _and_ actually provide the Logging File (ie responding 404 is not good).

Cheers

Francois