Asp.Net Core Web API Client/Server Application | Visual Studio 2019

Summary

This tutorial video guides viewers through creating ASP.NET Core Web API applications using Visual Studio 2019. It begins with an introduction to Web API and its use in building HTTP services accessible by various clients. The presenter demonstrates setting up a Web API server project, removing default configurations, and creating a simple GET method in a controller. A console application is then added as a client to interact with the server. The process includes configuring the client to make HTTP requests and handle responses. The video concludes with running both projects to display the data retrieved from the server, encouraging viewers to explore and build upon the concepts introduced.

Takeaways

• 😀 The video is a tutorial on creating ASP.NET Core Web API for both client and server applications using Visual Studio 2019.
• 🔍 The presenter explains that a Web API is an application programming interface for a web server or web browser.
• 🛠 ASP.NET Core Web API is a framework for building HTTP services accessible by clients such as browsers and mobile devices.
• 📚 The video demonstrates how to create a new project in Visual Studio 2019, specifically an ASP.NET Core Web API project named 'Web API Server'.
• 🚫 The tutorial opts not to configure the application for HTTPS and disables Open API support for simplicity.
• 📝 The script guides viewers through removing the default 'Weather Forecast' controller and creating a new 'Values' controller.
• 🔄 The presenter shows how to adjust the launch settings to point to the 'Values' controller instead of the default endpoint.
• 💻 A new Console App project is added to serve as the Web API client, named 'Web API Client'.
• 🔄 The video explains setting up multiple startup projects in Visual Studio to run both the server and client simultaneously.
• 📝 In the 'Values' controller, a simple GET method is created to return an array of strings as a response.
• 🔗 The client application uses HttpClient to make an asynchronous GET request to the server's URI and handles the response.
• 📡 The video concludes with running the projects and displaying the data retrieved from the server in the client console.

Q & A

What is the main topic of the video?

The main topic of the video is about creating and understanding ASP.NET Core Web API for both client and server applications using Visual Studio 2019.

What is a Web API?

A Web API is an application programming interface for a web server or a web browser, allowing access to services with HTTP requests from various clients like browsers and mobile devices.

What is ASP.NET Core Web API?

ASP.NET Core Web API is a framework for building HTTP services that can be accessed by any client, making it an ideal platform for creating RESTful applications on the .NET platform.

Why is Visual Studio 2019 used in the video?

Visual Studio 2019 is used as it is a powerful IDE that supports the development of ASP.NET Core applications, including Web APIs.

What is the first step in creating a Web API project in the video?

The first step is to create a new project in Visual Studio 2019 and select ASP.NET Core Web API as the project type.

Why is the 'Weather Forecast' sample removed in the video?

The 'Weather Forecast' sample is removed to create a clean slate for demonstrating the creation of a custom Web API without the default sample data.

What does the video suggest to do with 'Open API support'?

The video suggests unchecking the 'Enable Open API support' option, as it is not necessary for the demonstration in the video.

How is the Values controller used in the video?

The Values controller is used to create a simple GET method that returns a hardcoded array of strings, demonstrating a basic API endpoint.

What is the purpose of creating a Console App project in the video?

A Console App project is created to act as a client that will consume the Web API, showcasing how to make HTTP requests to the server.

How does the video handle the server URI in the client application?

The server URI is hardcoded in the client application's code after starting the server, ensuring the client knows where to send its requests.

What is the significance of setting the startup projects in Visual Studio?

Setting multiple startup projects allows both the Web API server and the client application to start simultaneously, which is useful for testing and development.

How does the video demonstrate handling responses from the Web API?

The video demonstrates checking if the response has a successful status code and then reading the content as a string. It also shows basic error handling by printing the response error code if the request fails.

What is the final step shown in the video?

The final step is running both the Web API server and the client application to see the data being displayed in the client's console, demonstrating a successful API call.

Outlines

00:00

🚀 Introduction to ASP.NET Core Web API

This paragraph introduces the topic of the video, which is about creating ASP.NET Core Web API for both client and server applications using Visual Studio 2019. The speaker encourages viewers to subscribe to the channel and provides a brief explanation of what a Web API is, highlighting its role as an application programming interface for web servers or browsers. ASP.NET Core Web API is described as a framework for building HTTP services accessible by various clients, including browsers and mobile devices, and is ideal for creating RESTful applications.

05:03

🛠 Setting Up the Web API Server Project

The speaker demonstrates the process of setting up a new ASP.NET Core Web API project in Visual Studio 2019. They guide viewers through creating a blank solution, adding a new project, and selecting the correct version of the .NET framework. The video shows how to configure the project by removing unnecessary features like HTTPS configuration and disabling Open API support. The speaker also explains how to remove the default Weather Forecast controller and create a new Values controller, adjusting the launch settings to reflect these changes.

10:17

🔧 Creating a Simple GET Method in Values Controller

In this paragraph, the focus is on implementing a simple GET method within the Values controller. The speaker creates a method named 'Gets' that returns a new instance of a string array containing some sample data like 'mango', 'banana', and 'apple'. They also mention the importance of removing the '/api' prefix from the controller's URI to avoid conflicts. The speaker emphasizes the simplicity of the task, aiming to keep the demonstration straightforward for the viewers.

🔄 Developing the Web API Client Console Application

The speaker proceeds to develop a console application that will act as a client for the Web API server. They guide the viewers through creating a new C# console application project and setting it up to run alongside the Web API server. The speaker then demonstrates how to use the HttpClient class to make an asynchronous GET request to the server's URI. They explain the process of awaiting the response, checking for a successful status code, and then reading the content of the response to display it in the console. The video concludes with a demonstration of running both the server and client applications simultaneously and displaying the fetched data.

Keywords

💡ASP.NET Core

ASP.NET Core is an open-source, cross-platform framework for building modern, cloud-based, Internet-connected applications. It is a key component of the .NET Core ecosystem and is used for developing web applications and APIs. In the video, ASP.NET Core is mentioned as the framework for creating a web API, which is a type of application programming interface specifically designed for web servers or web browsers.

💡Web API

A Web API is a set of protocols and endpoints that allow different systems to communicate with each other over the web. It is used for building HTTP services that can be accessed by various clients, including browsers and mobile devices. In the video, the presenter discusses creating a Web API using ASP.NET Core, which is intended to be a RESTful service.

💡Visual Studio 2019

Visual Studio 2019 is an integrated development environment (IDE) from Microsoft, used for developing applications across different platforms and languages. In the context of the video, it is the software used to create both the server and client applications for the web API, demonstrating its versatility for full-stack development.

💡RESTful

RESTful refers to the Representational State Transfer architectural style for networked hypermedia applications. It relies on a stateless, client-server, cacheable communications protocol, and in web services, HTTP is commonly used. The video mentions building RESTful applications on the .NET Core, which implies creating APIs that follow REST principles for easy consumption by clients.

💡Controller

In the context of ASP.NET Core, a controller is a class that handles incoming HTTP requests and returns HTTP responses. It is a central part of the MVC (Model-View-Controller) pattern used in web application development. The video script describes creating a 'ValuesController' as part of setting up the web API.

💡HTTP GET method

The HTTP GET method is used to request data from a specified resource. It is one of the most common HTTP methods and is typically used to retrieve information. In the video, a GET method is added to the ValuesController to return an array of strings, demonstrating a simple way to serve data via the API.

💡Client

In the context of web APIs, a client is any application or service that consumes the API to perform actions or retrieve data. The video script includes the creation of a console application that acts as a client to the web API, illustrating how a client might interact with the server.

💡HTTP Client

The HTTP Client is a class in the System.Net.Http namespace that allows for sending HTTP requests and receiving HTTP responses. In the video, the presenter uses an HTTP Client to make a request to the web API from the client application, showcasing how to consume the API.

💡URI

URI stands for Uniform Resource Identifier, which is a string of characters used to identify a name or a resource on the Internet. In the video, the presenter mentions setting up a URI for the web API client to make a request to the server, which is essential for locating and accessing the API endpoint.

💡Startup Project

In Visual Studio, a startup project is the project that runs when you start the debugging or run process. The video script describes setting multiple startup projects, allowing both the web API server and the client application to start simultaneously, which is useful for testing and running both parts of the application at once.

💡Open API Support

Open API, previously known as Swagger, is a specification for machine-readable interface files for RESTful APIs. It allows for the generation of interactive documentation and client SDKs. The video mentions disabling Open API support, which suggests that while it's a valuable tool for API development, it's not required for the basic demonstration being given.

Highlights

Introduction to ASP.NET Core and Web API for both client and server applications using Visual Studio 2019.

Definition of Web API as an application programming interface for web servers or browsers.

Explanation of ASP.NET Core Web API as a framework for building HTTP services accessible by various clients.

Demonstration of creating a new ASP.NET Core Web API project in Visual Studio 2019.

Instructions on removing the default Weather Forecast example from the Web API project.

Guidance on adding a new controller to the Web API project.

Details on configuring the launch settings for the Web API project.

Process of creating a simple GET method within the Values Controller.

Introduction of creating a Console Application project for the Web API client.

Setting up multiple startup projects in Visual Studio to run both server and client simultaneously.

Implementation of an async method to handle HTTP GET requests in the client application.

Use of HttpClient to make requests to the Web API server from the client application.

Explanation on handling the response from the Web API server in the client application.

Demonstration of checking the success of the HTTP response and processing the data.

Displaying the retrieved data from the Web API server in the client application console.

Encouragement for viewers to subscribe to the channel for more upcoming videos.

Invitation for viewers to explore and build upon the concepts learned in the video.

Transcripts

hello everyone

welcome back once again in this video

we will look at asp.net core

web api both client

and server applications

using the visual studio 2019

but before we get started please make

sure you subscribe to the channel if you

haven't

so let's get to it then so what is

really a web

api so web api is just an

application programming interface for

either a web server

or their web browser so what is also

a web asp.net call web api

so that is

a framework for building http services

that can access by

that can be accessed by any client

including browsers

mobile devices etc

it is also an ideal platform for

building restful applications

on the dot net call so enough of all of

these so let's get to it then so as you

can see here i've got visual studio 2019

update so

we go straight into it then i actually

have a blank solution so i'm just going

to go by adding a new

project so if you don't have this then

obviously you just go

you just start by actually adding a new

project

then you can get to the solution side so

i'm just going to add a web api

asp.net call with api right

so we're just gonna click nest so here

we're just gonna name it

um web

api server

right so i'm just gonna click nest and

here we can select

whatever version of dot net framework to

target so we're not gonna look too much

into that

so obviously we're not going to actually

configure the application for https as

it's not necessary for this video and

also we're just going to remove the

enable open api support as well

so we're just going to uncheck this bit

i saw so in this

obviously we click on the create

so now we've actually got

a sample template created for us so what

we do is we're just going to remove this

bit here

um the weather forecast

and then we come inside the controller

that we remove the console

a bit as well so please follow this

part very carefully so once we we

actually remove

that yeah what we do next is we come

inside their

dependencies right so about before that

yeah

we right click our controller and then

we add a new item

so i'm just gonna select airspeed.net

call so what we do is we're going to add

an

empty api controller

so here as you can see we've got an

empty api

controller which is values controller

right

so once we've added the controller we've

got values controller so we actually

expand the properties then the launch

settings

so here as you can see we've got um the

launch url

to be weather forecast so we're going to

change this bit and

we've got the values controller so we're

just going to put values here instead

right so that's all we're going to do

for this bit we're just going to save

the file

and we can actually close it right so

the next bit obviously we're just going

to add a new

one more project and this project will

be

obviously a console app so it's a c

sharp console app right

and this project will be obviously

let's say web api

client

right so we add this as well we

click on the create and we should get

a console app created for us yeah so

as we can see here now the project is

all set to run

only the web api server so

whilst we're here we're just going to

right click on the solution

and then we come to the set startup

project

so as you can see i will click on the

multiple star project here

and then we we actually put both of them

on the start so that we can get both of

them started at the same time

so here we put start i saw we

apply the changes so as you can see the

changes

has been actually reflected here so

we've got multiple startup projects here

yeah so now what we do is we come inside

the values controller we're just going

to put nothing fancy for here

so we're just going to make a very

simple get method

so it's http get yeah

so we're just going to call this um

public

um string we're just gonna make some

string

array and what we call it is gets

so here what we do is we only are going

to return

a new instance of a string array

so we're just going to put some date as

in some day i

string this inside here so the first day

obviously i'm just going to put mango

the nest

i mean this is entirely up to you so you

can put whatever you want

but for this video i'm just gonna make

it as simple as possible

so we're just gonna put banana

and we're gonna pop her

and one more we're just gonna pour one

more

uh but um apple

just a moment please okay so

i mean i've actually got the comment

inside so i'm just going to pull it out

here

then then one

should go away so this is all we've

actually got there the get method so

what we do is we come inside

the client to web api client we open the

program

so here so right after the console.

right line here what we do is just gonna

put another another console.rt line here

so what we do is we're going to start by

using

so we're just going to put first

console the right line so here

we're just going to say press enter key

to continue

so what we do is we're just going to put

another console.red line here

and then what we do is we use the using

keyword so we'll be using

we're going to use http

client which will be clark clients

this will be according to the new

instance of our http client right

so here what we do is we actually

reference it

so we're going to use the the

system.net.http.http client

yeah so we're going to use the same for

this as well

system.html

yeah so that's what we're going to be

using now so what we do is we just put

inside a bracket so what we do is we

initialize a variable called

response this will be equal to so this

method what we do

is we're going to make the the main

method

async task

so here we're going to reference

system.task so

inside the response we're going to we

can await

yeah so we could say client

dot

get async

so we can put our uri

inside here so what we do is i'm just

going to make

the server to start up

just to start up yeah i'm going to set

it to start up

so you'll be just a server that will run

so we can get the uri

so actually before you can run with the

runner there's one more thing that

i need to show you

so we come inside the view values

controller so

basically here if you've got the slash

api just remove

that bit from the controller

uri yes so we stop it from running

then we come inside uh the programs are

cs code

so inside here we can paste the uri that

we just copied

inside here yeah

so what we can do is we can say

response dot ensure

success code

and then we can say if

response does is

success to success status code

that means we know that there is

successful the response is successful so

this is what we would do

we going to initialize a string variable

we know

it's a string array but we just we could

convert it to a string gallery but we're

just going to leave that for this video

so we could say

await response

dot content dot

reader string async

yeah so the next bit is obviously we

could say

console or rail line then we can put a

message inside the console

yeah so after that what we could just

do is else we put the else statement

here

so we could say console.rightline

a response

oh we could just leave it here

something like this you can just write

something like this so

response error code

will be so we can put the response code

here so if we say

response dot

status code yeah so that's what we're

going to leave for here for now

so as you can see it's very simple stuff

so what we do is we actually turn it

straight back to running the

the multiple projects so initialize

startup projects

so we've got them started already so

apply changes

and then we run it to see what actually

happens

so now we're just gonna wait for the so

that one is actually loaded

so we're just gonna put this bit here

and

actually get our console client

so we could press enter key to enter so

as you can see we've got the data now to

be displayed

here now so we could actually convert it

to our rate

it's just displaying a string so but you

get you get

what is going on here now so what i'm

going to do is leave the video here for

now

so you can actually explore it further

and build on

what you've actually learned from here

so once again

if you haven't subscribed the channel

please make sure you do because i've got

lots of videos coming up

stay blessed