OakLeaf Systems: November 2011

A compendium of Windows Azure, SQL Azure Database, AppFabric, Windows Azure Platform Appliance and other cloud-computing articles.

• Updated 11/29/2011 5:00 PM PST with articles marked • in the Marketplace DataMarket, Social Analytics and OData, Live Windows Azure Apps, APIs, Tools and Test Harnesses and Other Cloud Computing Platforms and Services sections.

Note: This post is updated daily or more frequently, depending on the availability of new articles in the following sections:

Azure Blob, Drive, Table, Queue and Hadoop Services
SQL Azure Database and Reporting
Marketplace DataMarket, Social Analytics and OData
Windows Azure AppFabric: Apps, Access Control, WIF and Service Bus
Windows Azure VM Role, Virtual Network, Connect, RDP and CDN
Live Windows Azure Apps, APIs, Tools and Test Harnesses
Visual Studio LightSwitch and Entity Framework v4+
Windows Azure Infrastructure and DevOps
Windows Azure Platform Appliance (WAPA), Hyper-V and Private/Hybrid Clouds
Cloud Security and Governance
Cloud Computing Events
Other Cloud Computing Platforms and Services

Azure Blob, Drive, Table, Queue and Hadoop Services

Alex Popescu (@al3xandru) asked Data Is the New Currency. But Who's Leading the Way? in an 11/29/2011 post to his myNoSQL blog:

In 2005, Tim O’Reilly said: “data is the next Intel Inside“. Today IDC Mario Morales (VP of semiconductor research) says data is the new currency. All’s good until you read the continuation:

And the companies that understand this are the ones already developing the analytics and infrastructure to extract that value—companies like IBM, HP, Intel, Microsoft, TI, Freescale and Oracle.

The article (nb: may require registration) continues by looking at what each of these companies are doing in the Big Data space, but focuses a large part on IBM Watson.

Going back to the question “who’s leading the Big Data way“, let’s take a quick look at the technology behind Watson. According to Jeopardy Goes to Hadoop and About Watson, Watson technology is based on Apache Hadoop, using an IBM language technology built on the Apache UIMA platform and running Linux on IBM boxes.

To me it looks like open source is leading the advances in Big Data and these large organizations are just connecting the dots (as in packaging these technologies for enterprise environments and contributing missing pieces here and there)^[1]. When did this happen before?

Or they are very secretive about their internal initiatives and research. ↩

Avkash Chauhan (@avkashchauhan) explained Windows Azure Queue can have 64KB message content and how 64KB content is calculated? on 11/28/2011

Windows Azure Queue can have a message content size up to 64KB per message. This update was included in Version 2011-08-18 and newer. If you are still on [an] old version, then Windows Azure Queue will have 8KB message.

This 64KB [size] refers to the size of the UTF-8 encoded message. The body of the request contains the message data in the following XML format.

A message must be in a format that can be included in an XML request with UTF-8 encoding. In the following example the highlighted message-content is considered as message content and its size can go up to 64 KB.
<QueueMessage>
<MessageText>message-content</MessageText>
</QueueMessage>
So this 64kb actual message content, not the raw message length, or Unicode binary length, or base64 encoded length when sent via http content.

More Info: http://msdn.microsoft.com/en-us/library/dd179346.aspx

See also Liam Cavanagh (@liamca) announced the availability of a new SQL Azure Labs Codename “Data Transfer” project in his How to upload your Excel and CSV data to the Cloud post of 11/28/2011 in the Live Windows Azure Apps, APIs, Tools and Test Harnesses section.

SQL Azure Database and Reporting

Cihan Biyikoglu continued his SQL Azure Federations series with Federation Metadata in SQL Azure Part 3 – Monitoring Ongoing Federation Operations on 11/28/2011:

In part 2 we talked about federation metadata history views. Federation history views only report operation[s] that completed. For monitoring ongoing operations federations provide a separate set of dynamic management views under sys.dm_federation_operation*. All federation operations such as CREATE, ALTER or DROP consist of a set of steps that are executed async. With all async commands, a sync part of the command sets up and kicks off the operation first.

Once the sync part is done, the control is returned to the executor of the TSQL. Then, SQL Azure in the background executes the async steps in the background. The initial sync part of these commands also set up the data for monitoring these async federation operations in the sys.dm_federation_operation* views. The views report metadata about the async operation such as the start date and time or the operation type that is running (ex: SPLIT or DROP etc) as well as the current progress of the operation.

Federation operation DMVs provide great information after operations have been kicked off. Here are a few useful queries that can help you monitor your federations;
-- see how long a repartitioning operation has been active
select datediff(ss,start_date,getutcdate()) as total_seconds, percent_complete, *
from sys.dm_federation_operations
GO

-- display members with active federation repartitioning operations
SELECT fmc.member_id, 
  cast(fmc.range_low as nvarchar) range_low, 
  cast(fmc.range_high as nvarchar) range_high, 
  fops.federation_operation_type
FROM sys.federations f 
JOIN sys.federation_member_distributions fmc 
ON f.federation_id=fmc.federation_id 
LEFT OUTER JOIN (
 SELECT fo.federation_id, fom.member_id, 
    fo.federation_operation_type, fom.member_type
 FROM sys.dm_federation_operation_members fom 
 JOIN sys.dm_federation_operations fo
 ON fo.federation_operation_id = fom.federation_operation_id 
    AND fo.federation_operation_type='ALTER FEDERATION SPLIT' 
    AND fom.member_type='SOURCE') fops
ON f.federation_id=fops.federation_id AND fmc.member_id=fops.member_id 
ORDER BY f.name, fmc.range_low, fmc.range_high
GO

MarketPlace DataMarket, Social Analytics and OData

• Microsoft Pinpoint added an item for my Microsoft Codename “Social Analytics” WinForms Client Sample on 11/29/2011:

Todd Hoff described DataSift Architecture: Realtime Datamining at 120,000 Tweets Per Second in an 11/29/2011 post:

I remember the excitement of when Twitter first opened up their firehose. As an early adopter of the Twitter API I could easily imagine some of the cool things you could do with all that data. I also remember the disappointment of learning that in the land of BigData, data has a price, and that price would be too high for little fish like me. It was like learning for the first time there would be no BigData Santa Clause.

For a while though I had the pleasure of pondering just how I would handle all that data. It's a fascinating problem. You have to be able to reliably consume it, normalize it, merge it with other data, apply functions on it, store it, query it, distribute it, and oh yah, monetize it. Most of that in realish-time. And if you are trying to create a platform for allowing the entire Internet do to the same thing to the firehose, the challenge is exponentially harder.

DataSift is in the exciting position of creating just such a firehose eating, data chomping machine. You see, DataSift has bought multi-year re-syndication rights from Twitter, which grants them access to the full Twitter firehose with the ability resell subsets of it to other parties, which could be anyone, but the primary target is of course businesses. Gnip is the only other company to have these rights.

DataSift was created out of Nick Halstead's, Founder and CTO of DataSift, experience with TweetMeme, a popular real-time Twitter news aggregator, which at one time handled 1.1 billion page views per day. TweetMeme is famous for inventing the social signaling mechanism, better known as the retweet, with their retweet button, an idea that came out of an even earlier startup called fav.or.it (favorite). Imagine if you will a time before like buttons were plastered all over the virtual place.

So processing the TweetMeme at scale is nothing new for the folks at DataSift, what has been the challenge is turning that experience into an Internet-scale platform so that everyone else can do the same thing. That has been a multi-year odyssey.

DataSift is position[ing] themselves as a realtime datamining platform. The platform angle here is really the key take home message. They are pursuing a true platform strategy for processing real-time streams. TweetMeme while successful, could not be a billion dollar company, but a BigData platform could grow that large, so that’s the direction they are headed. A money quote by Nick highlights the logic in neon: "There's no money in buttons, there's money in data."

Part of the strategy behind a platform play is to become the incumbent player by building a giant technological moat around your core value proposition. When others come a knockin they can't cross over your moat because of your towering technological barrier to entry. That's what DataSift is trying to do. The drawbridge on the moat is favored access to Twitter's firehose, but the real power is in the Google quality real-time data processing platform infrastructure that they are trying to create.

DataSift's real innovation is in creating an Internet scale filtering system that can quickly evaluate very large filters (think Lady Gaga follower size) combined with the virtuous economics of virtualization, where the more customers you have the more money you make because they are sharing resources.

How are they making all this magic happen? Let's see...

I described DataSift’s relationship to Microsoft Codename “Social Analytics” in my Microsoft Codename “Social Analytics” Windows Form Client Detects Anomaly in VancouverWindows8 Dataset post of 11/20/2011.

The Microsoft Social Analytics Team described Finding Top Message Threads for a Filter in an 11/28/2011 post:

This is the second post in a series where we explore Entities in the Social Analytics Lab API. Through this series of posts, we will provide details on how the Entities can be used to accomplish some basic scenarios in the Social Analytics lab.

In this scenario we’ll look at identifying top threads for one of the lab datasets. To accomplish this, you will need three Entities in our API (pictured below):

Filters

Filters are a central concept in storing and retrieving data in the Social Analytics Lab. You could think of the set of filters as a list of topics available in an Social Analytics Instance. For example, the Windows 8 lab includes the following filters:

Id

Name

1

DataAcquisition: Windows 8

2

DataAcquisition: Windows 8 on Twitter

3

DataAcquisition: Windows 8 on YouTube

4

Subscription Filter for @g_win8slice

6

Windows 8 and Tablet PCs

7

Windows 8

8

Non-Twitter

10

Windows 8 on Facebook

11

Windows 8 and Applications

12

Windows 8 Design and User Experience

13

Windows 8 and Applications 2

Notice that three of the Filters are labeled as Data Acquisition Filters. Filters can control what activity from social media channels is tracked in an instance of Social Analytics or it can be simply a materialized view over the social data tracked in an instance. With our permissions model for filter definitions, control over what Social Data is tracked in an instance can be controlled while giving many users permissions to define filters that are views over the data.

MessageThreads

We define a MessageThread as a post and all of its replies within a channel. MessageThreads are the primary unit of activity we use to track social channel activity. If you examine the MessageThreads entity, you’ll find a collection of measures described an aggregated view of the thread, including:

Replies

Answers

Likes

Retweets

IsQuestion

IsAnswered

PositiveSentiment

NegativeSentiment

The Replies field is a total of all replies of all types in the thread, so you don’t want to sum Replies and Answers etc., or you’ll be double-counting.

FilterResultCaches

FilterResultCaches represents what MessageThreads relate to all filters, and is one of the most useful Entities for analyzing Social Analytics data. Using the following LINQ Query in LinqPad:
( from f in FilterResultCaches 
  orderby f.MessageThread.Replies descending 
  where f.FilterId == 6 && f.MessageThread.Replies > 1
  && f.LastUpdatedOn > DateTime.Now.AddDays(-7) 
  select new 
  {
     f.MessageThread.Replies,
     f.Site.Name,
     f.MessageThread.PositiveSentiment,
     f.MessageThread.NegativeSentiment,
     f.MessageThread.LastReplyContentItem.Title,
     f.MessageThread.LastReplyContentItem.HtmlUrl,
   }).Take(10) 
We can find the Messagethreads with the most replies during the last 7 days in the “Windows 8 and Tablet PCs” filter:

Replies Name Positive Sentiment Negative Sentiment Title Html Url

126 twitter.com 0 0 RT @TheNextWeb: If the Kindle Fire nearly runs Windows 8, why do we need quad-core Android tablets? http://t.co/fcXyxiU1 by @alex on @TN ... http://twitter.com/RenoYuuki/statuses/138211182040449024

33 twitter.com 0 0 RT @blogtweetz: Nokia Tablet To Debut in Summer 2012 - Powered By Windows 8 ! http://t.co/EniexIKY via @Dazeinfo http://twitter.com/epremierleague/statuses/138931098318155776

13 twitter.com 0 0 RT @9to5mac: How well does Mac OSX run on Samsung’s Windows 8 Tablet? [Video] http://t.co/tvOJVmSj http://twitter.com/carlst3/statuses/139378162495791106

7 twitter.com 0 0 RT @Indiferencia: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/54Wf3Rza http://twitter.com/endamo/statuses/138029411483131905

6 twitter.com 0 0 RT @Entiendelas: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/bMvT7gXr http://twitter.com/Lacangri1412/statuses/137750579417055232

6 twitter.com 0 0 RT @dehaaspeter: BCG: Windows tablet populairder dan iPad van Apple : http://t.co/P4GedXkY #windows8 http://twitter.com/OscarMinkenberg/statuses/139273712657637376

5 twitter.com 0 0 RT @OfficeTH: โอ้วว้าว...!Win8 Tablet บน Nokia จะเฝ้ารออออ!!! http://t.co/4lFOjLmO http://twitter.com/opal_monkey/statuses/138607317817114624

4 twitter.com 0 0 RT @LeaNoticias: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/DjOAGG9k http://twitter.com/daichu_/statuses/138098502550040576

4 twitter.com 1 0 RT @Indiferencia: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/54Wf3Rza http://twitter.com/arknglzintetico/statuses/138627023793954817

4 twitter.com 0 0 RT @freddier: Tablet Samsung con Windows 8 [pic] http://t.co/cyENejTk #techdayschile http://twitter.com/GustavoRiveraMX/statuses/138723108952612864

Glenn Gailey (@ggailey777) continued his Dealing with Binary Resource Streams and Tombstoning series on 11/28/2011:

Sync’ing OData to Local Storage in Windows Phone (Part 3)

If you have been following this series, you know that I have been demonstrating a way to persist data from an OData feed to a local Windows Phone (“Mango”) device. Just to refresh, here are the benefits of maintaining a local cache of data:

Reduced amount of network traffic. This is the most important benefit to caching data locally. Otherwise, every time the app starts it has to hit the OData feed to load initial data, which is a huge waste of bandwidth for OData feeds that are relatively static.

Improved load time. It’s much faster to load data from the device than to make an HTTP request to the OData service.

App don’t need network access to start. When the app is dependent on remote data, it can’t really start well without a connection.

Puts the user in control. Users can decide on if and when to sync the local data to the OData service, since most of them pay for their data.

Reduced tombstoning serialization. When the entities are stored in local database, they can be retrieved from there, which means they don’t need to be serialized and tombstoned.

Note that I have published my completed project to MSDN Code Gallery as Using Local Storage with OData on Windows Phone To Reduce Network Bandwidth. This project contains my generated proxy classes, but not the T4 templates that I used to generate them (I’m holding the template code a little longer to make sure that I have the licensing and copyright stuff correct).

As of the last post, I was working on getting a nice solution to requesting and storing media resources, in this case binary image files. It turns out that, in general, the OData client library and Silverlight APIs make it rather easy to request binary data as streams from the data service and use this stream to create an image to store locally in isolated storage.

Requesting and Storing the Media Resource Stream

As I mentioned in an earlier post, a great solution (as long as you aren’t sending updates to the data service) is to create a new binding property in a partial class of the entity that returns the read stream URI. This time, because you are storing and retrieving of binary image data yourself, you need the extension property to return the actual BitmapImage for binding, which means you must deal with streams and not just the URI (and let the binding do the work).

Here is the partial class that defines the DefaultImage property:
// Extend the Title class to bind to the media resource URI. 
public partial class Title 
{ 
    private BitmapImage _image;

    // Returns the media resource URI for binding.  
    public BitmapImage DefaultImage  
    {  
        get  
        {  
            if (_image == null)  
            {  
                // Get the URI for the media resource stream.  
                return App.ViewModel.GetImage(this);  
            }  
            else  
            {  
                return _image;  
            }  
        }  
        set  
        {  
            _image = value;  
            OnPropertyChanged("DefaultImage");  
        }  
    }  
}
The GetImage method on the ViewModel first checks isolated storage for the image, and if it’s not there it makes an asynchronous BeginGetReadStream call to data service:
// Calls into the DataServiceContext to get the URI of the media resource. 
public BitmapImage GetImage(object entity) 
{ 
    // First check for the image stored locally. 
    // Obtain the virtual store for the application. 
    IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication();

    Title title = entity as Title; 
    MergeOption cacheMergeOption; 
    Uri entityUri;            

    // Construct the file name from the entity ID. 
    string fileStorageName = string.Format("{0}\\{1}.png", isoPathName, title.Id);

    if (!isoStore.DirectoryExists(isoPathName)) 
    { 
        // Create a new folder if it doesn't exist. 
        isoStore.CreateDirectory(isoPathName); 
    }

    // We need to handle the case where we have stored the entity but not the image. 
    if (!isoStore.FileExists(fileStorageName)) 
    { 
        // Try to get the key of the title entity; if it's not in the DataServiceContext, 
        // then the entity comes from 
        // the local database and it is not in the DataServiceContext, which means that 
        // we need to request it again to get the URI of the media resource. 
        if (!_context.TryGetUri(entity, out entityUri)) 
        { 
            // We need to attach the entity to request it from the data service. 
            _context.AttachTo("Titles", entity);

            if (_context.TryGetUri(entity, out entityUri)) 
            { 
                // Cache the current merge option and change it to overwrite changes. 
                cacheMergeOption = _context.MergeOption; 
                _context.MergeOption = MergeOption.OverwriteChanges;

                // Request the Title entity again from the data service. 
                _context.BeginExecute<Title>(entityUri, OnExecuteComplete, entity);

                // Reset the merge option. 
                _context.MergeOption = cacheMergeOption; 
            } 
        } 
        else 
        { 
            DataServiceRequestArgs args = new DataServiceRequestArgs();

            // If the file doesn't already exist, request it from the data service. 
            _context.BeginGetReadStream(title, args, OnGetReadStreamComplete, title);                    
        }

        // We don't have an image yet to set. 
        return null; 
    } 
    else 
    { 
        using (var fs = new IsolatedStorageFileStream(fileStorageName, FileMode.Open, isoStore)) 
        { 
            // Return the image as a BitmapImage. 
            // Create a new bitmap image using the memory stream. 
            BitmapImage imageFromStream = new BitmapImage(); 
            imageFromStream.SetSource(fs);

            // Return the bitmap. 
            return imageFromStream; 
        } 
    }            
} 
When the request is completed, the OnGetReadStream callback method is invoked, where EndGetReadStream is called first to write the stream to local storage and then to set the DefaultImage property of the specific Title entity, which causes the binding to be updated with the image.
private void OnGetReadStreamComplete(IAsyncResult result) 
{ 
    // Obtain the virtual store for the application. 
    IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication();

    Title title = result.AsyncState as Title;

    if (title != null) 
    { 
        // Use the Dispatcher to ensure that the 
        // asynchronous call returns in the correct thread. 
        Deployment.Current.Dispatcher.BeginInvoke(() => 
            { 
                try 
                { 
                    // Get the response. 
                    DataServiceStreamResponse response = 
                        _context.EndGetReadStream(result);

                    // Construct the file name from the entity ID. 
                    string fileStorageName = string.Format("{0}\\{1}.png", 
                        isoPathName, title.Id);

                    // Specify the file path and options. 
                    using (var isoFileStream = 
                        new IsolatedStorageFileStream(fileStorageName, 
                            FileMode.Create, isoStore)) 
                    { 
                        //Write the data 
                        using (var fileWriter = new BinaryWriter(isoFileStream)) 
                        { 
                            byte[] buffer = new byte[1000]; 
                            int count = 0;

                            // Read the returned stream into the new file stream. 
                            while (response.Stream.CanRead && (0 < ( 
                                count = response.Stream.Read(buffer, 0, buffer.Length)))) 
                            { 
                                fileWriter.Write(buffer, 0, count); 
                            } 
                        } 
                    }

                    using (var bitmapFileStream = 
                        new IsolatedStorageFileStream(fileStorageName, 
                            FileMode.Open, isoStore)) 
                    { 
                        // Return the image as a BitmapImage. 
                        // Create a new bitmap image using the memory stream. 
                        BitmapImage imageFromStream = new BitmapImage(); 
                        imageFromStream.SetSource(bitmapFileStream);

                        // Return the bitmap.                                    
                        title.DefaultImage = imageFromStream; 
                    } 
                }

                catch (DataServiceClientException) 
                { 
                    // We need to eat this exception so that loading can continue. 
                    // Plus there is a bug where the binary stream gets 
                    /// written to the message. 
                } 
            }); 
    } 
} 
Note that there currently is a bug where the client doesn’t correctly handle a 404 response from BeginGetReadStream (which Netflix returns) when that response contains an image stream, and it tries to write the binary data to the Message property of the DataServiceClientException that is generated. During debug, this did cause my VS to hang when I moused-over the Message property, so watch out for that.

Getting the Media Resource for a Stored Entity

Loading the media resource actually gets a little complicated for the case where you have stored the entity in local database, but for some reason you don’t also have the image file stored. The issue is that you only store the entity itself in the local database, but each tracked entity in the DataServiceContext has a companion EntityDescriptor object that contains non-property metadata from the entry in the OData feed, including the read stream URI. You first need to call AttachTo, which starts tracking the entity and creates a new EntityDescriptor. However, only the key URI value gets set in this new EntityDescriptor, which is immutable and is inferred from the metadata. The context has no way to guess about the read stream URI, which can be changed by the data service at any time. This means to get the read stream, you need to first call BeginExecute<T> to get the complete MLE (with the missing entry info including the read stream URI) from the data service. the following section from a previous code snippet is the part that checks the context for the entity, and if it’s not there, it requests it again from the data service:
// Try to get the key of the title entity; if it's not in the DataServiceContext, 
// then the entity comes from  the local database and it is not in the 
// DataServiceContext, which means that we need to request it again to get 
// the URI of the media resource. 
if (!_context.TryGetUri(entity, out entityUri)) 
{ 
    // We need to attach the entity to request it from the data service. 
    _context.AttachTo("Titles", entity);

    if (_context.TryGetUri(entity, out entityUri)) 
    { 
        // Cache the current merge option and change it to overwrite changes. 
        cacheMergeOption = _context.MergeOption; 
        _context.MergeOption = MergeOption.OverwriteChanges;

        // Request the Title entity again from the data service. 
        _context.BeginExecute<Title>(entityUri, OnExecuteComplete, entity);

        // Reset the merge option. 
        _context.MergeOption = cacheMergeOption; 
        } 
    } 
    else  
    {  
        DataServiceRequestArgs args = new DataServiceRequestArgs();

        // If the file doesn't already exist, request it from the data service.  
        _context.BeginGetReadStream(title, args, OnGetReadStreamComplete, title);   
     }

     // We don't have an image yet to set.  
     return null; 
}
Because this method requires two call to the data service (one to refresh the entity and the second to get the stream), it might be better to store a generic not found image rather than make two calls. Another option would be to further extend the entity type on the client to include a property that can be used to store the read stream URI. Then, you can just make a regular HttpWebRequest to the URI , now stored with the entity, to get the image from the data service—one request instead of two. (This would be another property that must be removed from a MERGE/PATCH/POST request for entities that are not read-only.) Less request, but a bit more complex still.

Tombstoning with Locally Stored Entity Data

I mentioned that one of the benefits of storing entity data in local database was (potentially) simplified tombstoning, and in this exact scenario of read-only data, this is the case. By always trying to load from the local database (and isolated storage) first, we don’t need to serialize entity data during tombstoning. Notice that in the SaveState and RestoreState methods we are only persisting the current page number and the selected title, instead of using the DataServiceState to serialize out all the in-memory data tracked by the DataServiceContext:
// Return a collection of key-value pairs to store in the application state. 
public List<KeyValuePair<string, object>> SaveState() 
{ 
    // Since we are storing entities in local database, 
    // we don't need to store the OData client objects.               
    List<KeyValuePair<string, object>> stateList 
        = new List<KeyValuePair<string, object>>();

    stateList.Add(new KeyValuePair<string, object>("CurrentPage", CurrentPage)); 
    stateList.Add(new KeyValuePair<string, object>("SelectedTitle", SelectedTitle));

    return stateList; 
}

// Restores the view model state from the supplied state dictionary. 
public void RestoreState(IDictionary<string, object> storedState) 
{           
    // Restore view model data. 
    _currentPage = (int)storedState["CurrentPage"]; 
    this.SelectedTitle = storedState["SelectedTitle"] as Title; 
}
Of course, this also get more complicated when we need to support data updates because we need to attach objects from the local database to the DataServiceContext before we can send changes to the data service, and DataServiceContext is where changes are tracked.

Conclusion

The sample that I put together is based on the OData client library for Windows Phone and is limited to download-only. This solution for persisting entity data from an OData service in local database (and isolated storage for blobs) is probably best for reference data or for data that is relatively static. For data that changes frequently or that must be updated by the client, you probably need to continue to request fresh data from the data service on startup. You could also use timestamp properties in the data model to implement a more incremental kind of downloading of updated entities, but you will be unable to detect deletes from the data services. Also, you will need to first re-attach stored entities to the DataServiceContext to leverage the conflict detection and identity management facilities provided by the client. Then you can request all entities in the feed with a timestamp value greater than the last download date, and use a MergeOption value of OverwriteChanges to make sure that the client is updated with server values (of course the DataContext will need to be updated with the new values too). Another option might be to use the DataServiceState to serialize and persist an entire context and collections in local storage as serialized XML. How you handle this will depend greatly on your scenario, how often the data changes, and how much data your application must deal with to run.

As you can see, compared to the total problem set of maintaining OData entities offline, this solution is rather basic (it does what it does by leveraging the local database), but it’s not truly “sync,” despite the title of the series. In the next post, I plan to discuss another option that provide a much more traditional and comprehensive kind of bi-directional synchronization between data on the Windows Phone device and data in the cloud by using an OData-based sync service.

Stay tuned…

Matt Wrock described how to Track Nuget Downloads using OData, RSS and Ifttt.com in an 11/28/2011 post:

In this post I am going to show you how you can be notified of new downloads of any Nuget package via email from a service that will poll Nuget every 15 minutes. If email sounds overly intrusive, there are other options. So If this sounds interesting, read on.

If you have open source projects hosted on Nuget and you are a bit on the OCD (obsessive compulsive disorder) side, you are frequently tempted to wander over to Nuget.org and check out your download stats. Well, I have finally started to notice that I spend a fair amount of time every day, checking the Nuget site as well as other sites that may provide key indicators of my projects’ health. For instance I like to check for new followers or twitter mentions. Unfortunately, a lot of this time is spent simply waiting for a web page to load and reveal to me that there is no new information. So not only is this unproductive but it can lead to negative thoughts and emotions.

There are many pharmaceutical options available here, but I am not a Medical doctor and it would be unwise for me to give advise of a psychiatric nature. However I do have some technical solutions that simply require a computer with access to the world wide web. If you lack either of these, I have nothing to offer and you should now leave this page.

Ok. good. It’s just you and me now….hmm…this is uncomfortably intimate. No matter…

Switch from a Pull to a Push model

What I found myself craving was a way to let all of this information come to me and announce to me that there is new data rather than me having to spend time pinging several sources for what is likely to be no new information. In my case, I really wanted my phone to beep or vibrate when I get a new download, follower or mention. For me, this would not be a nuisance given the small amount of data. If you owned jQuery, you may want a more unobtrusive notification. Fortunately the solution I am about to propose can channel notifications through a variety of mediums.

Enter If-this-then-that ifttt.com

A few months ago I noticed a new referring link on my blog from a domain called ifttt.com. I visited the link and perused the site and discovered that it provided a way of creating sort of mash ups of various social media. ifttt stands for If This Then That. And the site simply allows you to create rules of If something occurs (new tweet, RSS feed item, DropBox item, etc.) Then some other thing should be triggered such as an email sent or a tweet or facebook update, etc. I have to admit my initial impression was “That’s dumb.” Then about a week later Scott Hanselman blogged about this service having been duly impressed by its offerings. I still didn’t really get it.

Not sure why I didn’t see the value right away but I see it now. Last week I setup a number of tasks that have freed me of the constant compulsion to check these various web sites for new data. I have a rule that will send me an email whenever my project has a new Github follower or a new mention on twitter. I have tasks that tell me when I have new stack overflow comments or new stack overflow points. All of these tasks were relatively easy to set up using ifttt.com. ifttt’s very friendly GUI provides an extremely simple way to send an email to yourself triggered by a new tweet or RSS feed item.

Here is an example of the task that sends me an email when my project RequestReduce is mentioned on twitter:

It is honestly trivial to set this up.

But Nuget Has no RSS Feed with items representing downloads

Currently Nuget provides no RSS feed or any notification option for subscribing to download stats beyond what is displayed on the project search results and individual project details pages. I don’t know if there are plans to implement this by the Nuget team in the near future, but I wanted something up and running soon that didn’t need to be polished.

All Nuget data available from the website is exposed through an OData feed

I knew that the data I was interested in was available via OData. There are a few posts out there that talk about this. I found that David Ebbo’s post had the detail I deeded to get started. With the name of any Nuget package Id, you can get its total download count via the public Nuget OData endpoint at http://packages.nuget.org/v1/FeedService.svc.

Here is an example query using LinqPad:

Creating a custom RSS Feed to broadcast new downloads

Currently as far as I can tell, there is no facility built into ifttt to consume this OData format. Yes, you can expose OData as an ATOM feed but given the Nuget schema, this would only be useful if you wanted to be notified of new versions. Essentially each version is a child entity of the master Packages entity. DownloadCount is simply a property associated with each version. Note that a version has both a VersionDownloadCount and a DownloadCount. The first is simply the count for a single version and the latter is the aggregate count of all combined versions released in a single package.

At first I tried playing with Yahoo Pipes and some other online RSS builder apps but none of these was going to work. At least not simply. I didn’t want to spend a lot of time on this since what I wanted was really quite simple and could be coded up fairly trivially. So I ended up just writing my own feed generator and I took the opportunity to create my first Azure application. I plan to blog more specifically on the azure specific details later and how they differed from my work with an AppHarhor application.

Here is the RSS Generator code:
public class FeedHandler : IHttpHandler
{
    private const string NugetServiceUri = "http://packages.nuget.org/v1/FeedService.svc";
    private readonly IDictionary<string, IList<SyndicationItem>> 
        packageDownloadCounts = new ConcurrentDictionary<string, IList<SyndicationItem>>();

    public bool IsReusable
    {
        get { return true; }
    }

    public void ProcessRequest(HttpContext context)
    {
        var packageName = context.Request.QueryString["packageId"];

        var nugetContext = new Nuget.GalleryFeedContext(new Uri(NugetServiceUri));
        var last = (
            from x in nugetContext.Packages 
            where x.Id == packageName && x.IsLatestVersion 
            select new { x.DownloadCount, x.Version }).First();

        var items = GetSyndicationItems(packageName, last.DownloadCount);
        var nugetUrl = string.Format(
            "{0}/Packages(Id='{1}',Version='{2}')", NugetServiceUri, packageName, last.Version);

        var feed = new SyndicationFeed("Nuget Download Count Feed",
           "Provides the current total download count for a Nuget Package",
           new Uri(nugetUrl), nugetUrl, items.Last().LastUpdatedTime,
           items);
        using (var xmlWriter = XmlWriter.Create(context.Response.OutputStream))
        {
            feed.SaveAsRss20(xmlWriter);
            xmlWriter.Flush();
            xmlWriter.Close();
        }

        context.Response.ContentType = "text/xml";
        context.Response.End();
    }

    private IList<SyndicationItem> GetSyndicationItems(string packageName, int count)
    {
        IList<SyndicationItem> items;
        lock (packageName)
        {
            if (packageDownloadCounts.ContainsKey(packageName))
                items = packageDownloadCounts[packageName];
            else
            {
                items = new List<SyndicationItem>();
                packageDownloadCounts.Add(packageName, items);
            }
            var title = string.Format("{0} has {1} total downloads", packageName, count);

            if (!items.Any(x => x.Title.Text == title))
                items.Add(new SyndicationItem(
                   title,
                   "",
                   new Uri(string.Format("http://nuget.org/packages/{0}",
                                         packageName)), Guid.NewGuid().ToString(),
                   new DateTimeOffset(DateTime.UtcNow)));
            while (items.Count > 20)
                items.RemoveAt(0);
        }

        return items;
    }
}
You can grab the full Visual Studio Solution from https://github.com/mwrock/NugetDownloadFeed. Not much happening here. Its just a handler that takes a packageId in the query string and then checks the odata feed to see if there are more downloads than there were since the last time it checked. If there are, it creates a new feed item.

ifttt.com will poll this feed every 15 minutes. I currently have this feed up and running at http://wrock.cloudapp.net/downloadFeed.axd. Anyone is free to use it but I provide no guarantee for stability or longevity. That said, I have no plan to change the endpoint or bring it down. However, I may clean the code up a bit and offer it as a Nuget package so that anyone can host their own feed.

Consuming the feed from an ifttt.com Recipe

Beyond the creation of “one off” tasks. ifttt provides a means of encapsulating common task logic into a reusable “Recipe.” These are handy if you find yourself creating the same task again and again with the only difference being a single variable. In my case here, I wanted to create three tasks. One for each of my Nuget projects. It also seemed reasonable that others may want to make use of this as well. So I created a recipe that anyone can use in order to create their own Nuget Download Notification task. Simply create an ifttt account (Super fast and easy to do) and go here: http://ifttt.com/recipes/9302.

As the directions state, simply replace my Package Id RequestReduce with the Package Id that you are interested in.

If you do not want to be notified by email, you have several different options. You could have it tweet from a specific account, send an SMS message or create an Evernote entry. And there are many more options than that.

I’d really like to hand it to the folks at @ifttt for creating this ingenious service and wish them the best of success!

Windows Azure AppFabric: Apps, Access Control, WIF and Service Bus

Dhananjay Kumar (@debug_mode) described Supported Token Formats and Protocols in ACS in an 11/28/2011 post:

To get authenticated via Windows Azure ACS [the] relying party need[s] to obtain a token. Token[s] can be in different formats.

Possible token formats are as below,

SAML 1.1 and SAML 2.0

It stands for Security Assertion Markup language.

It is wildly used token format.

It is used in Single sign on

It is used in clam based authentication

it provides a XML schema for token and protocol used in authentication

SAML version 2.0 was approved as an OASIS Standard in March 2005

There are two types of schema for SAML

SWT

It stands for Simple Web Token.

It works on Simple Web Token specification.

SWT work on key value pair. All the required information is present in form of encrypted key value pair.

Key value pairs are relying party specific.

There are few keys which have to be present always in SWT token. They are as below,

Supported Protocols

ACS has to use some protocols to communicate either with the service or web application. Supported protocols are as below

Supported Token Protocols combination

ACS sends tokens over the protocol supported on the token format. Supported token and protocols are as below

Windows Azure VM Role, Virtual Network, Connect, RDP and CDN

No significant articles today.

Live Windows Azure Apps, APIs, Tools and Test Harnesses

• My (@rogerjenn) Test-Drive SQL Azure Labs’ New Codename “Data Transfer” Web UI for Copying *.csv Files to SQL Azure Tables or Azure Blobs post of 11/29/2011 provides step-by-step instructions for migrating *.csv files to new SQL Azure tables:

… To give Codename “Data Transfer” a test-drive, do the following:

1. Navigate to https://web.datatransfer.azure.com/ and register with your Windows Live ID to open the landing page:

Note: A What file designations are we missing? link isn’t visible in the preceding screen capture. Click the link to open a Tell Us Where Else You Would Like Us to Send Your Data text to add an additional Windows Azure data type. I requested Windows Azure Tables, which I understand is a feature currently under consideration.

Saving *.csv Files to SQL Azure Tables

…

3. Complete the form:

Note: Missing or invalid entries are emphasized in red when you click the Next button. Retyping the entry doesn’t remove the red tinge.

…

9. Click the Data icon to open a grid to display the new ContentItems table’s rows:

Detailed instructions for migrating data to Windows Azure blobs will be added tomorrow (11/30/2011).

Note: See the Liam Cavanagh (@liamca) announced the availability of a new SQL Azure Labs Codename “Data Transfer” project in his How to upload your Excel and CSV data to the Cloud post of 11/28/2011 article below (in this section.)

David Gristwood pointed out An interesting Windows Azure architectural discussion – synchronizing multiple nodes by Josh Twist in an 11/29/2011 post:

One of the interesting architectural discussions that comes up when designing highly scalable systems, such as those that run on Windows Azure, is how to co-ordinate multiple “nodes” so that they use use unique keys within an application or system. It sounds a fairly trivial task, but as with lots of engineering issues, when you examine it in more depth, there is more to this than first appears.

Fortunately, a colleague of mine, Josh Twist, who used to work at Microsoft in the UK, but now a Program Manager in the Windows Azure team, wrote an interesting article on this subject in MSDN Magazine, and I have pointed a few folk to the article, so its well worth a read.

Avkash Chauhan (@avkashchauhan) described a Silverlight front end calling to WCF Service, all in one Windows Azure Web Role Sample in an 11/29/2011 post:

I was asked recently to provide a sample which has Windows Azure Web Role with Silverlight front end, calling to WCF service which is hosted in the same Windows Azure Web Role. I decided to share those details and sample with everyone. This sample is very back code generate all through respective wizard and templates. I just added a few things to get them all working in one sample.

Create a cloud project name SLWCFWebRole and add WCF Service Web Role name WCFServiceWebRole as below:

Now add a new Silverlight project name SilverlightApp to your SLWCFWebRole application which is set to have:

SilverlightApp is hosted in existing Web Role

“Enable WCF RIA Services” to connect with WCF Service hosted in SLWCFWebRole

Now we need to add the WCF Service reference to our SilverlightApp. You can use several ways to get it included in the application.

Here, I just launched, WCFServiceWebRole in my browser so I can get active service URL (http://localhost:37000/Service1.svc ) to add in my SilverlightApp:

Once I have the active service URL http://localhost:37000/Service1.svc I added it to my SilverlightApp as below:

After it you will see that ServiceReference1 is included in your SilverlightApp as below:

If you open ServiceReferences.ClientConfig you will see the URL for the Web Service as below:
<configuration>
<system.serviceModel>
<bindings>
<basicHttpBinding>
<binding name="BasicHttpBinding_IService1" maxBufferSize="2147483647"
maxReceivedMessageSize="2147483647">
<security mode="None" />
</binding>
</basicHttpBinding>
</bindings>
<client>
<endpoint address="http://localhost:37000/Service1.svc" binding="basicHttpBinding"
bindingConfiguration="BasicHttpBinding_IService1" contract="ServiceReference1.IService1"
name="BasicHttpBinding_IService1" />
</client>
</system.serviceModel>
</configuration>
Very Important:

You should remember that when your WCF Web Role application will run in Compute Emulator it will not use http://localhost/* instead it will use IP address as http://127.0.0.1:81/

Also when the same application will run in Windows Azure cloud the URL will be something http://<your_service_name>.cloudapp.net

So when you run this application in Compute Emulator or Windows Azure Cloud, you would need to change the about endpoint address to correct one.

Now let’s add necessary code in SilverlightApp to make a call to WCF Service as below:

Edit MainPage.xaml to add one label and TextBox name TextBox1 as below:

Now edit MainPage.xaml.cs as below to initialize WCF Service reference ServiceReference1 and then implement a call to service contact “GetData” as below:
public partial class MainPage : UserControl
{
public MainPage()
{
InitializeComponent();
ServiceReference1.Service1Client client = new ServiceReference1.Service1Client();
client.GetDataCompleted += new EventHandler<ServiceReference1.GetDataCompletedEventArgs>(client_GetDataCompleted);
client.GetDataAsync(20); // Here we are passing integer 20 from Silverlight app to WCF Service
}
void client_GetDataCompleted(object sender, ServiceReference1.GetDataCompletedEventArgs e)
{
textBox1.Text = e.Result.ToString();
// Here we are receiving the results "string + Int value" from WCF Service and then writing into
// Silverlight app text box
}
}
Now set SilverlightAppTestPage.aspx as your startup page in WCFServiceWeRole and launch your application in Compute Emulator.

You will see the web page was launched however you will see the following Exception:

Error: An error occurred while trying to make a request to URI 'http://localhost:37000/Service1.svc'. This could be due to attempting to access a service in a cross-domain way without a proper cross-domain policy in place, or a policy that is unsuitable for SOAP services. You may need to contact the owner of the service to publish a cross-domain policy file and to ensure it allows SOAP-related HTTP headers to be sent. This error may also be caused by using internal types in the web service proxy without using the InternalsVisibleToAttribute attribute. Please see the inner exception for more details.

The exception occurred only because ServiceReferences.ClientConfig is pointing to http://localhost:37000/Service1.svc to connect to WCF Service which is wrong as we are running this application in Windows Azure Compute Emulator at http://127.0.0.1:81/Service1.svc as below:

Now let modify ServiceReferences.ClientConfig to point correctly to WCF Service in compute Emulator as below:
<configuration>
<system.serviceModel>
……..
<client>
<endpoint address="http://127.0.0.1:81/Service1.svc" binding="basicHttpBinding"
bindingConfiguration="BasicHttpBinding_IService1" contract="ServiceReference1.IService1"
name="BasicHttpBinding_IService1" />
</client>
</system.serviceModel>
</configuration>
Run the application again in Windows Azure Compute Emulator and you will see the correct and expected result as below:

Now to run this application in Windows Azure, you can add clientaccesspolicy.xml in the WCFServiceWebRole application as below:
<?xml version="1.0" encoding="utf-8"?>
<access-policy>
<cross-domain-access>
<policy>
<allow-from http-request-headers="SOAPAction">
<domain uri="*"/>
</allow-from>
<grant-to>
<resource path="/" include-subpaths="true"/>
</grant-to>
</policy>
</cross-domain-access>
</access-policy>
Now you can deploy this application to Windows Azure Cloud however you would need to make a necessary change to reflect correct WCF endpoint URL when application is running in Windows Azure Cloud. This change is made again in ServiceReferences.ClientConfig.

For example your Windows Azure service name is “TestSLWCFWebRole” then you can edit ServiceReferences.ClientConfig as below:
<configuration>
<system.serviceModel>
……..
<client>
<endpoint address="http://testslwcfwebrole.cloudapp.net/Service1.svc" binding="basicHttpBinding"
bindingConfiguration="BasicHttpBinding_IService1" contract="ServiceReference1.IService1"
name="BasicHttpBinding_IService1" />
</client>
</system.serviceModel>
</configuration>
Now you can package and deploy this service to Windows Azure Service TestSLWCFWebRole, production slot and you will see the correct and expected results:

You can download the full sample from codeplex:

http://silverlightwcfwebrol.codeplex.com/

Matthew Weinberger (@M_Wein) reported Microsoft Brings Cloud Integrator Nimbo into Azure’s Inner Circle in an 11/29/2011 post to the TalkinCloud blog:

Microsoft has invited New York-based cloud integrator and service provider Nimbo into its Windows Azure Circle Program, which enables Microsoft partners to advise on the future of the platform-as-a-service cloud.

Apparently, Nimbo has been a huge channel proponent of Microsoft Windows Azure and very proactive about promoting it to clients. In the press release, Nimbo said it’s been responsible for moving plenty of its enterprise customers to Azure-based solutions, from development and deployment through support. In fact, Nimbo is the cloud service provider that hosts the Windows Azure user group in New York and New Jersey.

“We work with the Windows Azure Platform because of its powerful toolset and familiar development environment. Our customers have responded favorably to its flexibility both in pricing and depth of features,” said Washington Leon-Jordan, Nimbo’s vice president of Technology, in a prepared statement.

And as a member of this Windows Azure Circle Program, Nimbo claimed its customers will benefit from the expanded access to Microsoft’s cloud team and resources. And in return, Microsoft gets to pick Nimbo’s collective brains about features, services and outreach that Windows Azure needs to focus on to compete in the crowded PaaS market.

Between this and the recent expansion of the Cloud Champions Club, it seems as though Microsoft is really looking to bring partners deeper into its cloud ecosystem and roadmap. TalkinCloud will continue to track Microsoft’s cloud partner momentum, so stay tuned.

Read More About This Topic

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Microsoft Q1 Earnings Meet Expectations but Vague on Cloud

Microsoft Windows BUILD: Azure Announcement Roundup

Michael Kan (@Michael_Kan) asserted “Agreeya Mobility will build applications that can draw on data from Azure, Sharepoint and other Microsoft apps” in a deck for his Protocol deal to bring compatible Microsoft apps to iOS, Android article of 11/29/2011 for Network World:

Microsoft said on Tuesday it will license the protocols for many of its enterprise systems to a company that will develop compatible applications for non-Microsoft mobile operating systems, including Google's Android and Apple's iOS.

Agreeya Mobility will develop a suite of mobile applications that will be compatible with Microsoft products such as Remote Desktop Services, Windows Azure, Active Directory and SharePoint.

The goal with the applications is to make it easier for employees to use their consumer gadgets for work, said Microsoft's Sandy Gupta, general manger for its open solutions group.

By licensing Microsoft's protocols, Agreeya will be able to build, for example, an application that will allow workers to view documents on SharePoint on their personal device.

The employee could then print documents on a company printer. "Obviously, this is one step, a concrete step, allowing enterprise services to interoperate with mobile applications," Gupta said.

Microsoft has made similar licensing agreements with other providers to develop such apps, but those were intended for only one device or one type of operating system, Gupta said. The latest agreement will mean a wider range of mobile devices will be included, he said.

Agreeya Mobility, a subsidiary of Agreeya Solutions, works with device manufacturers mainly in Asia to develop software products for handsets and tablets. The company plans to launch the suite of apps in March, said Agreeya Mobility CEO Krish Kupathil.

Several manufacturers are already testing the applications, although Kupathil declined to name the companies. Agreeya wants to work with manufacturers to embed the applications on their devices. The products will also be made available in application stores and other outlets.

Liam Cavanagh (@liamca) announced the availability of a new SQL Azure Labs Codename “Data Transfer” project in his How to upload your Excel and CSV data to the Cloud post of 11/28/2011:

As a SQL Azure Program Manager at Microsoft, one of the most common questions we get from customers is how to get their data into the cloud. Just like SQL Server, SQL Azure has import tools like BCP that allow you to build scripts to load your data. I have never been completely happy with these solutions because for many people, they just want a quick and easy way to load their data and don’t want to mess around with complex command line tools or deal with firewall issues associated with connecting on-premises systems to the cloud. That was a primary reason why our group chose to create a SQL Azure Lab called: Microsoft Codename “Data Transfer”.

The purpose of this data transfer service is really simple. To give you an easy way to load your Excel or CSV (Comma Separated) files into SQL Azure. All you need to do is tell us where you want us to load your data to, point us at the file and we will do the rest.

OakLeaf Systems

Wednesday, November 30, 2011

Test-Drive SQL Azure Labs’ New Codename “Data Transfer” Web UI for Copying *.csv Files to SQL Azure Tables or Azure Blobs

Saving *.csv Files to SQL Azure Tables

Saving *.csv files to Windows Azure Blobs

Tuesday, November 29, 2011

Windows Azure and Cloud Computing Posts for 11/28/2011+

Azure Blob, Drive, Table, Queue and Hadoop Services

SQL Azure Database and Reporting

MarketPlace DataMarket, Social Analytics and OData

Filters

MessageThreads

FilterResultCaches

Sync’ing OData to Local Storage in Windows Phone (Part 3)

Requesting and Storing the Media Resource Stream

Getting the Media Resource for a Stored Entity

Tombstoning with Locally Stored Entity Data

Conclusion

Switch from a Pull to a Push model

Enter If-this-then-that ifttt.com

But Nuget Has no RSS Feed with items representing downloads

All Nuget data available from the website is exposed through an OData feed

Creating a custom RSS Feed to broadcast new downloads

Consuming the feed from an ifttt.com Recipe

Windows Azure AppFabric: Apps, Access Control, WIF and Service Bus

Windows Azure VM Role, Virtual Network, Connect, RDP and CDN

Live Windows Azure Apps, APIs, Tools and Test Harnesses

Saving *.csv Files to SQL Azure Tables

Read More About This Topic

Id	Name
1	DataAcquisition: Windows 8
2	DataAcquisition: Windows 8 on Twitter
3	DataAcquisition: Windows 8 on YouTube
4	Subscription Filter for @g_win8slice
6	Windows 8 and Tablet PCs
7	Windows 8
8	Non-Twitter
10	Windows 8 on Facebook
11	Windows 8 and Applications
12	Windows 8 Design and User Experience
13	Windows 8 and Applications 2

Replies	Name	Positive Sentiment	Negative Sentiment	Title	Html Url
126	twitter.com	0	0	RT @TheNextWeb: If the Kindle Fire nearly runs Windows 8, why do we need quad-core Android tablets? http://t.co/fcXyxiU1 by @alex on @TN ...	http://twitter.com/RenoYuuki/statuses/138211182040449024
33	twitter.com	0	0	RT @blogtweetz: Nokia Tablet To Debut in Summer 2012 - Powered By Windows 8 ! http://t.co/EniexIKY via @Dazeinfo	http://twitter.com/epremierleague/statuses/138931098318155776
13	twitter.com	0	0	RT @9to5mac: How well does Mac OSX run on Samsung’s Windows 8 Tablet? [Video] http://t.co/tvOJVmSj	http://twitter.com/carlst3/statuses/139378162495791106
7	twitter.com	0	0	RT @Indiferencia: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/54Wf3Rza	http://twitter.com/endamo/statuses/138029411483131905
6	twitter.com	0	0	RT @Entiendelas: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/bMvT7gXr	http://twitter.com/Lacangri1412/statuses/137750579417055232
6	twitter.com	0	0	RT @dehaaspeter: BCG: Windows tablet populairder dan iPad van Apple : http://t.co/P4GedXkY #windows8	http://twitter.com/OscarMinkenberg/statuses/139273712657637376
5	twitter.com	0	0	RT @OfficeTH: โอ้วว้าว...!Win8 Tablet บน Nokia จะเฝ้ารออออ!!! http://t.co/4lFOjLmO	http://twitter.com/opal_monkey/statuses/138607317817114624
4	twitter.com	0	0	RT @LeaNoticias: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/DjOAGG9k	http://twitter.com/daichu_/statuses/138098502550040576
4	twitter.com	1	0	RT @Indiferencia: Nokia lanzará tablet con Windows 8 en junio de 2012 http://t.co/54Wf3Rza	http://twitter.com/arknglzintetico/statuses/138627023793954817
4	twitter.com	0	0	RT @freddier: Tablet Samsung con Windows 8 [pic] http://t.co/cyENejTk #techdayschile	http://twitter.com/GustavoRiveraMX/statuses/138723108952612864