Astoria futures: offline-enabled data services

infoblog » Astoria futures: offline-enabled data services

infoblog » Astoria futures: offline-enabled data services — Thu, 23 Oct 2008 05:33:40 GMT

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re: Astoria futures: offline-enabled data services

Chris — Thu, 23 Oct 2008 18:28:19 GMT

I definitely believe this is the right direction. The shift to smart client technologies (WPF, silverlight, etc.) is going to demand sync/offline design models. We have been deciding whether we wanted to tackle this development in a one-off scenario, and have decided against it due to time constraints and complexity. I believe if you're team delivers a CTP in Q4 or early Q1, we may be in a position to start testing it in parallel with our development.

Astoria Online/Offline

Mike Taulty's Blog — Fri, 24 Oct 2008 00:37:55 GMT

Tantalising post from the Astoria team.

re: Astoria futures: offline-enabled data services

Asheesh Soni — Fri, 24 Oct 2008 01:31:12 GMT

Definitely!

Every time I discuss software requirements with my clients, they say..."All that sounds good, but can you make it like Outlook, so we could work offline and then sync it later?"

Some how, I have to explain them how it'll blow their budget.

And I wish... wouldn't it be nice if we had offline enabled data services?

Well... there you are... talking about exactly what we need!

re: Astoria futures: offline-enabled data services

Asheesh Soni — Fri, 24 Oct 2008 04:41:59 GMT

Instead of a really really long comment in this post, I have blogged about our Scenario, Existing Architecture, and Project Requirements here:

http://asheeshsoni.blogspot.com/2008/10/astoria-futures-offline-enabled-data.html

There is also a poll on the sort of clients that'll consume your Astoria Offline services.

Feel free to discuss how you think your organization / applications could utilize Astoria Offline, and what features you look forward to in it.

Cheers

Asheesh Soni

re: Astoria futures: offline-enabled data services

Sven — Mon, 27 Oct 2008 12:55:12 GMT

I'm wondering which data storage mechanism Astoria OffLine will be employing to cache the data locally.

Since PDA's seem to come into the picture I'm guessing Sql Server Compact will be a strong contender there.

Oh Wait, Steve Lasker is involved (http://blogs.msdn.com/stevelasker/archive/2008/10/18/evolution-or-revolution-for-moving-to-offline-architectures.aspx) so there's no need for guessing anymore :-)

re: Astoria futures: offline-enabled data services

pabloc — Mon, 27 Oct 2008 20:29:11 GMT

Sven: yes, our primary focus for the offline client storage is SQL Server Compact for devices and desktop scenarios, although we're also exploring having support for other options as well, such as SQL Server Express for the desktop case.

Stories of what worked best in your applications are welcome, as it can help guide our decisions around this.

-pablo

re: Astoria futures: offline-enabled data services

Sven — Tue, 28 Oct 2008 01:55:03 GMT

Pablo, thanks for answering. Unfortunately I have no stories to tell about what worked best. We're still in the planning stages when it comes to local data caching. In fact, we're still planning our move to Silverlight.

The only thing I can offer is that the scenario where "server and client are built in collaboration, as part of the same development team" applies to us.

And I think it will apply to many teams that are going to port their N-tiered Winforms apps to WPF/Silverlight + Astoria as we are. So if you have to postpone support for the other scenario "where client and server are independent" to V2, that would be acceptable, IMHO.

-Sven

re: Astoria futures: offline-enabled data services

Neil W — Tue, 28 Oct 2008 05:46:47 GMT

For very light weight applications (such as Windows Mobile) the choice to focus on CE is spot on. Unfortunatly, most applications (in my humble opinion) will focus on LAPTOP application development. Due to very limited nature of CE as a database (no t-sql, no views, stored procedures, no xml, no role based security) I would love to see focus put on the Express edition. This will allow for very robust client/database applications to be developed.

re: Astoria futures: offline-enabled data services

James H — Tue, 28 Oct 2008 20:40:44 GMT

This sounds very much like an application we are developing at my company right now except that we were not able to use CE, we are using Sql Express 2008 and http merge replication from the desktop back to our server. Compact edition does not support some of the features we use such as stored procedures and the new file stream data type. I would like to see Sql Express supported as well as CE.

re: Astoria futures: offline-enabled data services

ChrisLamont-Mankowski — Wed, 29 Oct 2008 02:22:20 GMT

Since now is the time to influence the design ... I'd really appreciate the ability to synchronize a subset of data; either on a per-table basis, or on a WHERE restriction. This is because I usually deal with hundreds of thousands of rows; where only a certain select group of rows is relevant to each user who would sync. I'd like to limit the cached response to a certain date range, or to exclude some BLOB columns. This is comparable to the "Download Headers Only" feature in Outlook....

It would be nice to have the ability to sync my app to Astoria and also to Azure without having to re-port my code again. I'm expecting to be in the situation where I had just ported my code from a legacy access techology to Astoria/EF. I wouldn't be happy doing it again to support the cloud.

The final entry on my wish list would be an interface (or built in support) for caching pages of data. In my head, there seems to be a natural fit with caching and sync... In other words, transparently cache data as I work with the Data.Services.Client. This would be very helpful for my low bandwith clients.

re: Astoria futures: offline-enabled data services

pabloc — Wed, 29 Oct 2008 18:33:07 GMT

Neil/James: thanks for the feedback on SQL Express...will definitely take this into account.

Chris: let me comment on each item separately:

Subsets: yes, absolutely, we want to support sync'ing a subset of the data and we're exploring a couple of approaches. A couple of the challenges involved with this are cross-record dependency (a WHERE clause alone won't do, you need to make sure that you take a subgraph with no outgoing dependencies). Do you have a few examples the context of your applications of how you'd like to slide the data?

Regarding Astoria versus Azure, I agree that it makes sense. We're working with the SQL Data Services folks to explore this space. It's still early in the process, but it's certainly an area we'd like to look into more.

Caching: I hesitate about this a bit. I'm not a big fan if "magically seamless" interfaces, as when the differences start to permeate to the interface (and most of the time they do) the model breaks and the application assumptions fall appart. I tend to go with the explicit route more...but that's more of a style thing. Point taken.

-pablo

re: Astoria futures: offline-enabled data services

Nikunj Mehta — Fri, 31 Oct 2008 02:51:16 GMT

Pablo,

You state your aversion to caching and seamless online/off-line applications. If the data service is provided by Astoria, then there is no problem. However, if the data source is not Astoria-based then sync falls apart, and there is no chance of getting the full set of data locally in a way that guarantees that "all the data required for offline" is stored locally at sync time.

This is no different from the SOAP story, where everyone thought it would enable interoperable services only to find that the technologies were good enough only for intranet solutions built with the same tools and technologies on both sides of the interaction.

If you are interested in seeing advances made in the area of cache syncing standard AtomPub services (which by the way are way more interoperable than Astoria-only data sources), then you should check out the details of AtomDB. My blog http://o-micron.blogspot.com has details about AtomDB and so does the feed technology center on OTN http://oracle.com/technology/tech/feeds/.

I hope this comment makes its way to your blog post. I appreciate your interest in this area and look forward to an invigorating discussion.

Nikunj Mehta

Alpha preview of Project Codename "Astoria Offline" coming soon

Project Astoria Team Blog — Tue, 04 Nov 2008 02:02:00 GMT

As we already discussed in a previous blog post , one of the problem spaces related to data services

re: Astoria futures: offline-enabled data services

pablo cibraro — Mon, 24 Nov 2008 21:50:16 GMT

Hi Pablo,

Apart from having some client support for the sync framework (and the service side counterpart as well), are you planning to include feedsync extensions as part of the ATOM feed that can be get from the output of an existing ADO.NET service ?. This would be definitively good for using any technology that talks FeedSync on the other end.

Thanks

Pablo.

Real World Apps in Days not Weeks

ASPInsiders — Fri, 16 Jan 2009 05:26:30 GMT

I've given a number of presentations on ADO.NET Data Services (formerly codenamed: "Astoria")

Announcing Project Codename “Astoria Offline”, Alpha Preview

Project Astoria Team Blog — Sat, 07 Mar 2009 23:44:51 GMT

In October of last year we started to talk publicly about an exploration project we called “Astoria