Tuesday, April 14, 2015

How to fix 'thumbprint' attribute is invalid error in Azure Cloud Service


While i was configuring a web role in a cloud service project to use SSL certificate, I was adding my certificate to the Service Configuration file (cscfg) as follows:

  <Certificate name ="MyCertTest" thumbprint="cd947ee0b988e3b144d9fc39af47128dec68b731" thumbprintAlgorithm="sha1"/>

After i copied the thumbprint value from my certificate and paste it in the configuration file (cscfg) i found that there is an underlying error under thumbprint attribute and when i build i get the following error:

the xml specification is not valid: the 'thumbprint' attribute is invalid the pattern constraint failed

Here is the steps on how to fix it:

1) Remove any spaces from the thumbprint value.
2) There was a hidden character at the beginning and end of this string and once i removed it the underlying error in the cscfg file went away.
3) Save your changes and build!
4) Deploy your cloud service to Azure.

Hope this helps.

Sunday, April 12, 2015

How to return JSON objects from Web API 2

Hi All,

I was trying to return an object from web api 2.0 and i was getting the following error:

The 'ObjectContent`1' type failed to serialize the response body for content type 'application/xml; charset=utf-8'.

The inner exception message was stating the following:

Type 'Newtonsoft.Json.Linq.JToken' is a recursive collection data contract which is not supported. Consider modifying the definition of collection 'Newtonsoft.Json.Linq.JToken' to remove references to itself.

Sample method:

public async Task<MyObject> GetTransactionDetails(string transactionId)


   MyObject obj = new MyObject();
   obj.Name = "Mostafa dev";
   return obj;

The solution:

Add the following 2 lines in Global.asax file under App_Start method, This will force the web api to return Json formats and to ignore references to itself for Newtonsoft.Json dll.

 protected void Application_Start()
            // Force to use Json formatter and ignore reference looping.
            GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;


Hope this helps.

Wednesday, July 02, 2014

Understanding, Designing, and Implementing Big Data Solutions in Azure


I am writing this blog post to point to an important published article from Microsoft Patterns and Practices Team on understanding, designing and implementing Big Data Solution on Windows Azure using HDInsight.

Want to know what is big data ? what is being used for ? Do you have a need for it ? what is the best scenarios to think about adopting to big data tools?
The answer for these questions are covered under the first section of Understanding Big Data on below link:


Second section of this article is covering how to design a scalable big data solutions in Azure platform using HDInsight. Would you use big data to explore your data and extract patterns, Apply BI techniques, Build ETL integration tools, Automation data processes all are covered on below link:


Third section of this article is covering how to using Azure as PaaS to implement your Big Data Solution using HDInsight including how to provision your first Hadoop cluster node and all required configurations for storing your big data files, build end-to-end solutions and visualizing your data:


Hope this helps!


Friday, June 13, 2014

How to: Create ASP.NET MVC Authentication tables in an existing database

Hi All,

I am writing this blog post to show how to migrate or move the standard MVC authentication tables into your existing database in your asp.net web application.

When you create a MVC web application in VS 2013, VS embed a sql server database in your project, and this project is being used as a source of asp.net membership. Since you will not use this database as an embedded file and you want to have it as part of your existing database in SQL Server instance. The file is created under App_Data folder. To see the .mdf file click on Show all files in the solution explorer.
You can see the contents of this database and all tables in the server explorer window.

How to create those tables in SQL server ?

First, you can delete the .mdf file in App_Data folder. Since we don't need any of these tables.Then, we need to update the default connection string in the web.config to point to our database.

    <add name="DefaultConnection" connectionString="Data Source=SERVER\INSTANCENAME;Initial Catalog=DBNAME;Integrated Security=True" providerName="System.Data.SqlClient" />

Third, Open Nuget Package Manager and write the following commands:

Add-Migration Init

Check out your database, all ASP.NET membership tables with Prefix Asp have been create and then you can test it out by running your application and execute membership actions such as Signing up or Signing in to your application.

Created tables after running above commands:

Hope this helps.


-- ME

Tuesday, June 10, 2014

Getting started with Solr for .NET architects & developers - part 1

Hi folks,

I am writing this blog post to provide some tips and insights on using open source search technologies such as Solr in your solutions and applications.

Here are my notes:
1) Solr is an open source search server product. It is free and one of the most trusted, mature search products in the market.

2) Solr uses lucene, lucene is the heart of Solr search server product. Lucene is the full text service or component that is used in Solr which provides all search, index and queries capabilities.

3) Lucene is a java based library to create, manage, and retrieve inverted index files.

4) Inverted index is a specialized data structure by Lucene to handle queries to text based documents.

5) Using full text feature that is available in some DBMS is not a replacement for Solr, Solr provides advanced search, query and ranking capabilities.

6) Solr provides on top of lucene full text capability the following features: pagination, sorting, faceting, auto-suggest, spell checker, hit highlighting, data modeling, grouping, and standard http API to integrate with your solutions.

7) Each Solt server has only one home, the path of the home is $SolrInstallation/example/solr, where $SolrInstallation is the path where you installed solr binaries.

8) Each Solr server can contain more than 1 core, each core contains its index data and configuration.

9) Solr web application is stored under solr.web folder which contains all servelts, html and js files.

10) Solr is running on Jetty as an application server. Google is using Jetty in its App Engine platform.

Hope this helps.

References: Solr in Action

Friday, April 25, 2014

Unable to retrieve metadata for unrecognized element 'providers' when adding a controller in VS 2013


I was trying to add a new controller in my project using Visual Studio 2013. I was using Code First Entity Framework for my data access. I tried to build and clean the project few times before adding the new controller; but still was getting this error message when  adding a new controller to my web api project.

Here is the error message:

The solution is the following:
1) Open the web.config file in your project.
2) Scroll down until you see entity framework section.
3) This is how it will be looking:

    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
        <parameter value="v11.0" />
      <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />

4) Remove the providers section.
5) Save and you will be able to add new controllers!

Hope this helps!

Thursday, April 17, 2014

Error when running web applications that reference SharePoint dlls in IIS Express

Hi All,

I was developing a web application that reference SharePoint 2013 dlls, and since SharePoint server dlls in general runs on a 64 bit environment, i want to use IIS express in Visual Studio 2013 without the need to use full local IIS that runs on 64 bit.

I was getting this error message when i am running my web application:

Could not load file or assembly or one of its dependencies. 

and i was seeing in the yellow error page that the VS 2013 is using IIS express under c:\ program files (86)\ IIS Express folder which is the 32 bit.

I want to switch IIS express to 64 bit so i will be able to run my web application that references 64 bit SharePoint dlls. here is the solution for this:

From Visual Studio 2013 IDE:

Click on :  Tools --> Options --> Projects and Solutions --> Web Projects  --> Use the 64 bit version of IIS Express --> check this checkbox and save.

Once you save, make sure you exit any instance of the IIS express and try to re-run your project! It will run with no issues!