TOPIC: Creating
Cloud Application using Azure: Creating
simple cloud application, configuring an application, creating virtual machine,
deployment of application to Windows Azure Cloud, using Azure Storage Services,
using Azure Table Service, deployment of application to the production environment.
6.1
CREATING SIMPLE CLOUD APPLICATION
Creating a Simple Windows Azure Application
Here is an introduction to the
Microsoft Windows Azure platform.. You’ll start off with a very simple cloud
application.
Getting the Cloud Computing Tools Ready
To develop applications on the
Azure platform, you will need to get the necessary toolset downloaded and
installed. This includes Visual Studio 2010 and the Azure tool kit.
Fire up Visual Studio 2010. Click
to create a new project and select the Cloud node from under Visual C#
templates as shown in Figure 1.
Click OK to proceed. As soon as
you click OK, you are prompted to select the type of roles for the Azure
application as shown in Figure 2.
Figure 2: Selecting Roles
Select The ASP.NET Web Role. When
you hover your mouse over the selected role, you are prompted to determine if
you would like to delete it or rename it. Click the pencil icon to rename the
role as shown in Figure 3.
Figure 3: Renaming the Web
Role
In this case, rename it to
“MyASPNETWebRole”. Click OK for the project to be created.
Once you do this, Visual Studio
2010 does its code-behind and generates the item shown in Figure 4 within
Solution Explorer.
Figure
4: The Role added to Solution Explorer
You can toggle to the design view
of default.aspx to see if you like the layout and make any change you deem fit.
Figure 5 shows how the page looks currently.
Figure 5: The start of
your Cloud Computing application
You are now ready to run the cloud
application. One thing to note is that the Azure emulator needs to be run
elevated. Hence you will have to restart Visual Studio as elevated in case you
did not do so in the first place.
Once you Ctrl+F5, Visual Studio
readies the project to deploy to the emulator as shown in Figure 6.
Figure 6: Deploying the
cloud emulator
Once it is done, you can see the
following screen (Figure 7):
Figure 7: The loaded Cloud
emulator
Click OK to dismiss the dialog and
launch the emulator. The emulator sits in your system tray (the blue windows
icon as shown in figure 8.)
Figure 8: The Cloud
emulator in the System Tray.
Once the emulator launches, it
will go ahead and launch the default.aspx page.
Figure 9: Your Cloud
Application running in the emulator
There, you now have your first
cloud application running in the emulator. You can them proceed to deploy the
application to the cloud. You’ll learn how to do that deployment in the next
article!
6.2
CONFIGURING AN APPLICATION
Covered in 6.1
6.3
CREATING VIRTUAL MACHINE
CREATING VIRTUAL
MACHINE
In computing, a virtual machine
(VM) is an emulation of a particular computer system. Virtual machines
operate based on the computer architecture and functions of a real
or hypothetical computer, and their implementations may involve specialized hardware,
software,
or a combination of both.
Various different kinds of virtual
machines exist, each with different functions. System virtual machines (also
known as full virtualization VMs) provide a complete
substitute for the targeted real machine and a level of functionality required
for the execution of a complete operating
system. A hypervisor uses native execution to share and manage hardware,
allowing multiple different environments, isolated from each other, to be
executed on the same physical machine. Modern hypervisors use hardware-assisted virtualization,
which provides efficient and full virtualization by using
virtualization-specific hardware capabilities, primarily from the host CPUs.
Process virtual machines are designed to execute a single computer
program by providing an abstracted and platform-independent program
execution environment. Some virtual machines, such as QEMU, are designed to
also emulate
different architectures and allow execution of software applications and
operating systems written for another CPU or architecture. Operating-system-level
virtualization allows the resources of a computer to be partitioned via the
kernel's support for multiple isolated user space
instances, which are usually called containers and may look and feel like
real machines to the end users.
A virtual
machine (VM) is a software implementation of a machine (for example, a
computer) that executes programs like a physical machine. Virtual machines are
separated into two major classes, based on their use and degree of
correspondence to any real machine:
- A system virtual machine
provides a complete system platform which supports the execution
of a complete OS. These usually emulate an existing architecture, and are
built with the purpose of either providing a platform to run programs where
the real hardware is not available for use (for example, executing on
otherwise obsolete platforms), or of having multiple instances of virtual
machines leading to more efficient use of computing resources, both in
terms of energy consumption and cost effectiveness (known as hardware
virtualization,
the key to a cloud computing environment), or both.
- A process virtual machine
(also, language virtual machine) is designed to run a single program, which means that it supports
a single process. Such virtual machines are
usually closely suited to one or more programming languages and built with
the purpose of providing program portability and flexibility (amongst
other things). An essential characteristic of a virtual machine is that
the software running inside is limited to the resources and abstractions
provided by the virtual machine—it cannot break out of its virtual
environment.
STEPS
To Create new Virtual Machines,
you need to click on New
It will open a new dialog
for you. There are two options to create the Virutal Machines Quick Create
and From Gallery. I will go with Quick Create option. When I choose Quick
Create then it will open a form in right side where you can fill all the
details of Virtual Machines.
Another option is Size. It
provides you functionality to add different types of VM configuration like here
you can define the core of system and also memory.
Provide the name of your VM and
create user name and password for this. Here a very important option
is Region. You need to specify the Region as per your local and create virtual
machines.
It will be creating your Virtual
Machines, It will take few minutes to configure it.
Now, your Virtual Machine is ready
for you. Click to connect option to connect with your Virtual Machine.
When you click on CONNECT, it
will download a .rdp file for you. which contains all the configuration
for your VM.
Run
this "DotnetTutorial.rdp", it will open a dialog which will ask
for credetial of your Virtual Machines.
When you provide correct
credetials for this VM. It will open and it will look like as below.
Note: Don't forget to shutdown
your VM after complete your work. You can shutdown it from shutdown option as
below.
6.4
DEPLOYMENT OF APPLICATION TO WINDOWS AZURE CLOUD
` PUBLISHING
A WEB APPLICATION TO WINDOWS AZURE WITH VISUAL STUDIO
Creating a Windows Azure
Web Site
Navigate to http://manage.windowsazure.com/ and
either log into your account or sign up for a trial account.
Once you’ve logged into Windows Azure, you’ll see a variety of options on the left hand navigation. Select WEB SITES from the list:
Select +NEW at
the bottom left hand corner:
Select COMPUTE
-> WEB SITE -> QUICK CREATE, add a name
under URL and finally check CREATE WEB SITE:
Verify the site is created and
running and flip over to your Visual Studio development environment:
Create a web application or open
an existing web application using Visual Studio. When you’re ready to publish
the web application follow the steps below:
PUBLISHING PROCESS
Remember that web site you created
at the beginning? On the Profile Page you’ll want to utilize a publishing
profile from your Windows Azure account. I’ll describe how to do that next.
DOWNLOAD PUBLISHING FILE
Let’s take a moment to download
the publishing file…
Navigate to http://manage.windowsazure.com/ and
either log into your account or sign up for a trial account.
Once you’ve logged into Windows
Azure, you’ll see a variety of options on the left hand navigation. Select WEB
SITES from the list:
Select the web site you created in
the previous steps:
Select DASHBOARD
and then select “Download the publish profile”:
Save the publish profile to the
machine Visual Studio is installed on.
OK, back to the Publish
Web process in Visual Studio
Open up Visual Studio, load your
completed web application, and select BUILD from the menu and
then “Publish Selection”:
Select “Import…”
and navigate to the publish file you saved and select “Next >”
The Connection page will pull
information from the publish file and populate the fields for you. Verify the
details and select “Next >”
Finally the Preview page provides
a view of all the files to be uploaded to your Windows Azure Web Site:
Visual Studio will give you a log
of information as it deploys to Windows Azure:
Once the web application is
deployed, navigate to the site URL (in my case I used a self-signed certificate
for SSO):
Here is my site:
Congratulations, you’ve deployed a
web application to Windows Azure!
6.5
USING AZURE STORAGE SERVICES
Windows Azure BLOB storage
service can be used to store and retrieve Binary Large Objects (BLOBs), or what
are more commonly known as files. In this introduction to the Windows Azure
BLOB Storage service we will cover the difference between the types of BLOBs
you can store, how to get files into and out of the service, how you can add
metadata to your files and more.
There are many reasons why
you should consider using BLOB storage. Perhaps you want to share files with
clients, or off-load some of the static content from your web servers to reduce
the load on them. However, if you are using Azure’s Platform as a Service
(PaaS), also known as Cloud Services, you’ll most likely be very interested in
BLOB storage because it provides persistent data storage. With Cloud Services
you get dedicated virtual machines to run your code on without having to worry
about managing those virtual machines. Unlike the hard drives found in Windows
Azure Virtual Machines (the Infrastructure as a Service –IaaS- offering from Microsoft),
the hard drives used in Cloud Services instances are not persistent. Because of
this, any files you want to have around long term should be put into a
persistent store, and this is where BLOB storage is so useful.
Where Do
We Start?
BLOB Storage, along
with Windows Azure Tables and Windows Azure Queues make up the three Windows
Azure Storage services. Azure tables are a non-relational, key-value-pair
storage mechanism and the Queue service provides basic message-queuing
capabilities. All three of these services store their data within a Windows
Azure Storage Account which we will need to get started.
What Kind
of BLOB is that?
Any file type can be stored
in the Windows Azure BLOB Storage service, such as Image files, database files,
text files, or virtual hard drive files. However, when they are uploaded to the
service they are stored as either a Page BLOB or a Block BLOB depending on how
you plan on using that file or the size of the file you need to work with.
Page BLOBs are optimized
for random reads and writes so they are most commonly used when storing virtual
hard drive files for virtual machines: In fact, the Page BLOB was introduced
when the first virtual drive for Windows Azure was announced: the Windows Azure
Cloud Drive (at the time they were known as Windows Azure X-Drives). Nowadays,
the persisted disks used by Windows Azure Virtual Machine (Microsoft’s IaaS
offering) also use the Page BLOB to store their data and Operating System
drives. Each Page BLOB is made up of one or more 512-byte pages of data, up to
a total size limit of 1 TB per fil
6.6
USING AZURE TABLE SERVICE
Windows Azure Tables are a
non-relational, key-value-pair, storage system suitable for storing massive
amounts of unstructured data. Whereas
relational stores such as SQL Server, with highly normalized designs, are
optimized for storing data so that queries are easy to produce, the
non-relational stores like Table Storage are optimized for simple retrieval and
fast inserts. This article will cover
the very basics of Windows Azure Table storage and provide you with resources
and suggested topics to continue your learning.
Some people, when first learning
about the Windows Azure platform, find it hard to understand the purpose of the
Table Storage feature. This is especially
true of those who are familiar with developing applications using highly
relational data. To get a good
understanding of how a Key-Value Pair system differs from a traditional
relational database you can read Buck Woody’s article on the topic in his continuing
series: Data
Science Laboratory System - Key/Value Pair Systems.
The code examples provided in this
article are written using the Windows Azure .NET SDK 2.2 with Visual Studio
2013; however, like most services on Windows Azure this SDK simply calls a REST
based API in the background for you.
This underlying REST API allows for a variety of program languages and
platforms to use Windows Azure services and the Table Storage service is no
different. You can find documentation on
using the Table Storage service from node.js, Java, PHP, Python and Ruby at http://windowsazure.com.
Getting Started
To get started using the Table
service, we’ll first need to have a Windows Azure account and create a Storage
Account. You can get a free trial
account or, if you have a MSDN Subscription, you can sign
up for your Windows Azure benefits in order to try out the examples
included in this article. Once you have
an Azure account you can then create a storage account that can then be used to
store Tables.
What are Tables and Entities?
In Windows Azure Table
Storage, the term ‘Table’ is used to describe a grouping of entities. You can
loosely think of an entity as a row of data, but it’s more like a collection of
properties and values that were stored together within a table. Unlike relational databases, the entities
inside of a table do not need to have the same structure or schema. This means that we might have an entity that
stores properties about a product in the same table as an entity that stores
properties about the product options.
There are some rules about
entities: each entity can have up to 252 properties but the size of an entity
with all of the properties and values cannot exceed 1 MB. Table storage entities support the following
data types: Byte array, Boolean, DateTime, Double, GUID, Int32, Int64
and String (up to 64KB in size).
There are an additional three required system properties that must exist
on every entity: PartitionKey, RowKey and TimeStamp. The partition key is way to group entities
within a table and control the scalability of the table which we will touch on
in a bit. The row key is a unique
identifier for an entity within a given partition. The combination of partition key and row key
is the unique identifier for an entity within a table, comparable to a primary
key in a relational database. The Timestamp
property represents the last time the entity was modified and is managed by the
Storage sub-system. Any change you make
to Timestamp will be ignored.
6.7
DEPLOYMENT OF APPLICATION TO THE PRODUCTION ENVIRONMENT.
The User Acceptance Test Environment
The User Acceptance Test
(UAT) environment tests the deployment of the production-ready application in
an environment that closely resembles the production environment. In older
guidance, the UAT environment is named the staging environment. The name was
changed to UAT because, in SharePoint, a staging server deploys content that
still requires a final review to the production environment. The purpose of the
UAT environment is to identify any potential deployment issues and to allow
content to be reviewed by business owners. If the application passes these
tests, the business owners sign off on the application. Although the UAT
environment is optional for smaller applications where deployment failures are
not critical, it is still recommended.
The Production Environment
After the UAT tests are complete,
the application can be deployed to the production environment. Because the UAT
phase emulates the production deployment, the deployment steps are identical,
aside from any required name changes. For an example of how to deploy an
application to a production environment, see An Example of
Deploying a New Application. For publishing scenarios, there will often be
an authoring farm for creating and approving content. This environment is also
considered a production environment. Typically, solutions are applied to the
authoring environment before or at the same time as the production environment.
You may need to stagger the deployment if the changes impact the content in the
production environment. In this case, you may need to perform the following
steps:
- Apply
the solution to the authoring farm.
- Make
relevant updates to the production content in the authoring farm.
- Apply
the solution to the production farm.
- Deploy
the content to the production farm.
