[MUSIC]

Hi there.

This is James.

I'm a developer and teacher at tree house.

In this workshop we'll be taking a look at ASP.NET core,

Microsoft's latest web framework.

We'll start with answering the question, what is ASP.NET Core?

From the official documentation, ASP.Net Core is a new, open-source and

cross-platform framework for building modern cloud based Internet connected

applications, such as web apps, IoT apps, and mobile backends.

ASP.Net Core is a significant redesign of ASP.Net.

It's the biggest release of ASP.NET since version 1.0.

While some parts of ASP.NET Core will feel familiar such as MVC Controllers and

Views, other parts will seem completely new.

ASP.NET Core is a complete rewrite of the ASP.NET web framework.

It's no longer based on the System.Web assembly.

Breaking away from ASP.NET legacy code was necessary in order for

the ASP.NET development team to meet their stated design goals

of producing a fast cross-platform cloud friendly web framework.

ASP.NET Core places the focus on MVC and

Web API which have been merged into a single API.

We'll take a closer look at the convergence of MVC and

Web API later in this workshop.

Web forms and webpages are not currently available in ASP.NET Core,

nor are they likely ever to be.

Microsoft has made it clear that web forms and web pages will

remain as part of the full .NET framework and not brought into ASP.NET Core.

The ASP.NET team does have a new feature on the roadmap named view pages

that is similar to the functionality of web pages.

See the teacher's notes for more information.

ASP.NET Core runs on either .NET Core or the full .NET framework.

This gives you the flexibility to choose the target framework

that makes the most sense for your situation.

.NET Core is a new cross-platform version of .NET that runs on Windows,

Linux or Mac OS.

.NET Core has a flexible deployment model that gives you the option to deploy it

along with your application in addition to the more traditional side-by-side user or

machine-wide deployment options.

Only a subset of the .NET frameworks API surface has been implemented in .NET Core.

For instance,

the system drawing namespace is currently only partially implemented in .NET Core.

If your application needs to manipulate bitmaps

you'll need to use a third party library that's compatible with .NET core.

Or target the full .NET Framework.

.NET Core only supports a single app model, console apps.

While that might seem limiting,

it's possible to build other app models on top of it which is what ASP.NET Core does.

We'll see it later in this workshop how that works.

The .NET command line interface or CLI shipped as part of the .NET Core SDK.

The .NET CLI is a set of commands that allows you to create, build, run,

publish, test and package .NET Core apps all from the command line.

Having the CLI available, ensures that you can develop .NET Core apps

including ASP.NET Core apps, regardless of what platform or tools you're using.

For instance,

you can develop apps on Linux using the text editor of your choice.

CLI is even used by Visual Studio.

When using Visual Studio to develop .NET Core apps Visual Studio

delegates to the .NET CLI to build, run and publish your app.

ASP.NET Core and .NET Core are fully open source projects being hosted on GitHub.

Development is being done completely out in the open.

You can monitor or

contribute to the teams ongoing development discussions via GitHub issues.

Or you can fork any of the repos, fix a bug or

implement a feature and issue a poll request against the main repo.

ASP.NET Core is another example of the new Microsoft.

A Microsoft that is embracing open source development.

Unlike previous versions of ASP.NET,

ASP.NET Core is not a single monolithic assembly.

Instead it's delivered as a set of granular and well factored NuGet packages.

This gives you a true pay-for-what-you-use-model.

You only reference and deploy the packages that your application needs.

In order to realize ASP.NET Cores cross-platform design goal,

Microsoft needed a cross-platform server for running ASP.NET Core apps.

Kestrel is that server.

Kestrel is a cross-platform, managed web server based on libuv.

libuv is a multi-platform support library with a focus on

asynchronous IO that was developed primarily for

NodeJS, but is used by other projects including now, Kestrel.

Kestrel is the only supported web server for running ASP.NET Core apps.

IIS is no longer directly supported,

meaning that IIS does not host ASP.NET Core apps within its own process.

Instead IIS is used as a reverse proxy to Kestrel using

the ASP.NET Core module, HTTP module.

This is the same overall approach used for hosting NodeJS apps in IIS.

ASP.NET.Core apps running on Castro have

been able to achieve amazing performance benchmarks.

In February 2016 ASP.NET.Core achieved 1.15 million requests per second.

In a sense exceeded that number.

To put that number into perspective,

1.15 million requests per second represents a 2300%

gain over ASP.NET 4.6 or 800% gain over NodeJS.

The second decimal place, 0.05 million or

50,000 is around the total number of requests per second that

ASP .NET 4.6 could perform of the same type on the same hardware.

Most applications will never need this kind of throughput.

But having this kind of headroom will help ensure that your applications feel fast

and responsive.

As previously mentioned, ASP.NET Core runs on Windows, Linux, and macOS.

This is the first time that this is possible

using Microsoft supported runtimes and frameworks.

Cross-platform support opens up new development and deployment scenarios,

including being able to support mixed environment development teams.

And deploying your applications on to cloud hosted Linux virtual machines or

containers.

In this workshop I'll be working with both Windows and macOS.

To get started with ASP.NET Core development visit the new dot.net website,

where you can find detailed installation instructions and

downloadable installers for the platform of your choice.

In the next video we'll use the .NET CLI to create our first project.