topic Re: Snap shots, WCM. Time travel in Alfresco Archive

Snap shots, WCM. Time travel

rdanner — Sat, 14 Oct 2006 21:05:34 GMT

One of the most exciting features of WCM is the the ability to take a snapshot of the repository. Users can then walk back and forth through time over the collection of snapshots. This mechanism relys on the new repository infrastructure which is SVN like in nature. Almost like a collection of SVN

Re: Snap shots, WCM. Time travel

britt — Mon, 16 Oct 2006 16:27:48 GMT

Hi Russ,

For the foreseeable future snapshotting and time-travel, (not yet exposed in the preview) will not be available for the entire ECM stack. In order to achieve the 'magic' of time-travel, a significantly different repository architecture was needed, one that has some fairly fundamental semantic differences from the Alfresco DM repository. We will be working on tighter and tighter integration of the two models but don't have a clear path yet to "every feature available for all content".

Cheers,
Britt

Re: Snap shots, WCM. Time travel

rdanner — Wed, 18 Oct 2006 04:39:33 GMT

Hi Russ,

For the foreseeable future snapshotting and time-travel, (not yet exposed in the preview) will not be available for the entire ECM stack. In order to achieve the 'magic' of time-travel, a significantly different repository architecture was needed, one that has some fairly fundamental semantic differences from the Alfresco DM repository. We will be working on tighter and tighter integration of the two models but don't have a clear path yet to "every feature available for all content".

Cheers,
Britt

I can understand that. It is basically a whole new approach. Wow it will be neat to be able to apply the same type of functionality to the CIFS server and FTP server. These two functionalities are like tomcat in that if you are lying to the client (as WCM lies to tomcat about its application source) then we are fine because they as clients could care less.

I guess it gets harder when we start looking at some of the services and questioning how we map the old service APIs on top of the new repository. Maybe that is not difficult, perhaps its already done? Are the questions that remain revolve around how to expose the ability to access a snapsot?

I am a little confused is the repository different in the DM product vs the WCM. Obviously they are the same client. I was just peeking at the tables and it doesnt look entirely foreign to me. Have you already replaced NodeService with a new implementation for example?

Also, what are the intentions for handling data in external sources? Kevin mentioned in his pod cast that you would be able to role the system back to a point in time where your profile looked like X. I can see this as a possibility as long as your data stored within the alfresco repository. But virtualized applications and in particular a virutalized application from the past get a little bit tricky when they rely heavily on resources that are outside the system and perhaps no longer exist. Is there a good solution for this?

What do you imagine are the practical limitations of the viritualized application system?

Re: Snap shots, WCM. Time travel

marcus — Wed, 18 Oct 2006 14:11:49 GMT

What are the advantages of the current DM repository over the AVM? The obvious ones I can see at the moment are the lack of content rules, workflow and external interfaces like CIFS and FTP… if I was to write my own interface to use an AVM store for my documents, what other benefits of the current DM repository will I miss out on?

Re: Snap shots, WCM. Time travel

jcox — Fri, 13 Apr 2007 18:00:35 GMT

The alfresco webapp currently accesses two different repository
"engines" that live side-by-side at the moment: the DM and the AVM.

In general, the AVM is a more feature-rich design, and has a
more efficient implementation. Ultimately, it will probably be used
for DM, WCM, and SCM (i.e.: pretty much everything).

There are a few things such as JCR support and "associations" that
aren't there yet… and probably some other stuff too. The gap
keeps closing. Hopefully, the AVM will replace the DM engine
entirely at some point, but we want to be *very* careful to make
the transition as smooth as possible. Work on this might begin
during the summer/fall of this year (but that's just a guess).

As for the AVM, it now has CIFS support, and you can bring snapshots
in staging online and view them via the file viewer and/or in your
browser via the virtualization server (aka: "the web view").
Support for workflow in the AVM also exists.

- Jon