Monday, January 11, 2010

9 simple steps to run your first Azure Table Program

9 simple steps to run your first Azure Table Program


Introduction



Azure has provided 4 kinds of data storages blobs, tables, queues and SQL azure.
In this section we will see how to insert a simple customer record with code and
name property in Azure tables.

In case you are complete fresher and like me you can download my two azure basic
videos which explain what azure is all about Azure FAQ Part 1 :-
Video1 Azure FAQ Part 2 :-
Video2.

Please feel free to download my free 500 question and answer eBook which covers
.NET , ASP.NET , SQL Server , WCF , WPF , WWF , Silver light , Azure @ http://tinyurl.com/4nvp9t .


Whatwill we do in this article?


We will create a simple customer entity with
customer code and customer name and add the same to Azure tables and display the
same on a web role application.



Step 1:- Ensure you havethings at place


In case you are a complete fresher to Azure,
please ensure you have all the pre-requisite at place. You can read the below
article to get the basic prerequisite

http://computerauthor.blogspot.com/2010/01/simple-5-steps-to-run-your-first-azure.html

.



Step 2:- Create a web role project


The next step is to select the cloud service
template, add the web role project and create your solution.









Step 3:- Specify the connection
string


The 3rd step is to specify the connection
string where your table source is currently. So expand the roles folder , right
click on webroletable and select properties as shown in the below figure.





You will be then popped up with a setting tab.
Select the settings section, add a new setting, give a name to your connection
string and select type as ‘connectionstring’.





We also need to specify where the storage
location is , so select the value and select ‘Use development storage’ as shown
in the below figure. Development storage means your local PC currently where you
Azure fabric is installed.





If you open the ‘ServiceConfiguration.cscfg’
file you can see the setting added to the file.






Step 4:- Reference
namespaces and create classes


In order to do Azure storage operation we need
to add reference to ‘System.Data.Services.Client’ dll.





Once the dlls are referred, let’s refer the
namespaces in our code as shown below. Currently we will store a customer record
with customer code and customer name in tables. So for that we need to define a
simple customer class with ‘clsCustomer’. This class needs to inherit from
‘TableServiceEntity’ class as shown in the below figure.



The second class which we need to create is the data context class. The data
context class will take the entity class and enter the same in tables. You can
see in the below figure we have created one more class ‘clsCustomerDataContext’.






Step 5:- Define partition and
row key


The next step is to define the properties of
the customer class. In the below figure we have defined two properties in the
customer class customer code and customer name.



Every row in the table needs to be defined with a partition key and a unique row
key. In the constructor we have initialized the partition key with a text
“Customers” and the unique key is set to the current date time tick count.






Step 6:- Create your
‘datacontext’ class


The next step is to create your data context
class which will insert the customer entity in to azure table storage. Below is
the code snippet of the data context class.



The first noticeable thing is the constructor which takes in location of the
credentials. The second is the ‘Iqueryable’ interface which is used by the cloud
service to create tables in azure cloud service.





In the same data context we have created an
‘AddCustomer’ method which takes in the customer entity object and call’s the
‘AddObject’ method of the data context to insert the customer entity data in to
Azure tables.





Step 7:- Create the table structure on the
‘onstart’


The next step is to create the table on the
‘onstart’ of the web role.





So open ‘webrole.cs’ file and put the below
code on the ‘onstart’ event. The last code enclosed in curly brackets gets the
configuration and creates table’s structure.





Step 8:-
Code your client


The final thing is to code the client. So below
is the UI / ASPX file which we have created to insert the table entity values.





On the button click we need to consume the data
context and the entity class.



So the first step is to get the configuration setting of the data connection.


// Gets the connection string
var customer = CloudStorageAccount.FromConfigurationSetting("DataConnectionString");

The next step is to pass these credentials to
the data context class and create a object of the same.


// Create the customer datacontext object
var customerContext = new clsCustomerDataContext(customer.TableEndpoint.ToString(), customer.Credentials);

Flourish the entity object with data and pass
it to the data context class to add the same in to tables.


// Create the entity object
clsCustomer objCustomer = new clsCustomer();
objCustomer.CustomerCode = txtCustomerCode.Text;
objCustomer.CustomerName = txtCustomerName.Text;
// Pass the entity object to the datacontext
customerContext.AddCustomer(objCustomer);

Finally we loop through the context customer
entity collection to see if the customer is added in to the table.


//Loop through the records to see if the customer entity is inserted in the tabless
foreach (clsCustomer obj in customerContext.Customers)
{
Response.Write(obj.CustomerCode + " " + obj.CustomerName + "<br>");
}

Step
9:- Run your application


It’s time to enjoy your hard work, so run the
application and enjoy your success.





Source code


You can get the source code of the above sample
from
here


1 comment:

Techbee said...

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