Are you a web developer or do you write Internet of things (IoT) software? If so, you would know that many web and IoT development projects these days require the ability to establish a persistent connection between a client and a server without having to keep sending repeated requests from the client. For example, a user of a live chat would want to know in real time that they have received a new message. Or an IoT device may need to be sent a command in real time.
As you may also know, such functionality may be hard to implement. However, if you can build your server-side application on ASP.NET Core, there is a way to make this whole process easy. There is a library called SignalR, which is included in ASP.NET Core.
SignalR doesn't only enable you to achieve real-time two-way communication between applications. It also substantially simplifies the process of enabling all of this in the code. Under the hood, it uses various two-way communication protocols, such as WebSocket. However, it abstracts away all the implementation complexity of these protocols. To the developer, working with this library will mostly consists of writing simple and easily readable statements.
In this book, we will cover everything you would need to know about using SignalR on .NET 6, so you will see how to integrate it with the the latest features on ASP.NET Core 6 and C# 10. We will cover much more than you can find in the official documentation of the library. For example, you will learn how to connect a plain WebSocket client to it, which may help you to write a client in a language that isn't officially supported. Likewise, we will cover many concepts that aren't directly related to SignalR, but are important to its production-ready implementation. These would include single sign-on, certificate authorization, logging, metrics and scaling out. By the end of this book, you would be able to identify the situations where SignalR is the best tool for the job and you would be fully capable to implement it.
Author(s): Fiodar Sazanavets
Edition: 2022-05-15
Publisher: Leanpub
Year: 2022
Language: English
Pages: 160
Table of Contents
1 - Introduction to SignalR
What makes SignalR so great
Example use cases for SignalR
Who is this book for
The scope of this book
Prerequisites
How to use this book
Book structure
About the author
Getting touch with the author
2 - Setting up your project
Prerequisites
Setting up your environment
Setting up SignalR hub
Making SignalR hub strongly-typed
Summary
Test yourself
Further reading
3 - In-browser SignalR clients
Prerequisites
Setting up JavaScript client
Setting up Blazor WebAssembly client
Summary
Test yourself
Further reading
4 - External SignalR clients
Prerequisites
Setting up .NET client
Setting up Java client
Setting up a raw WebSocket client
Summary
Test yourself
Further reading
5 - Sending messages to individual clients or groups of clients
Prerequisites
Broadcasting messages to all clients
Sending messages to specific clients
Working with client groups
Summary
Test yourself
Further reading
6 - Streaming in SignalR
Prerequisites
What is streaming used for
Client streaming in SignalR
Server streaming in SignalR
Summary
Test yourself
Further reading
7 - Advanced SignalR configuration
Prerequisites
Configuring SignalR server
Configuring SignalR client
Pros and cons of MessagePack protocol
Summary
Test yourself
Further reading
8 - Securing your SignalR applications
Prerequisites
What is CORS and why it's important
Setting up single sign-on provider
Applying authentication in SignalR
Applying authorization in SignalR
Summary
Test yourself
Further reading
9 - Scaling out SignalR application
Prerequisites
Setting up Redis backplane
Running multiple hub instances via Redis backplane
Using HubContext to send messages from outside SignalR hub
Summary
Test yourself
Further reading
10 - Introducing Azure SignalR Service
Prerequisites
Setting up Azure SignalR Service
Adding Azure SignalR Service dependencies to your application
Overview of Azure SignalR Service REST API
Summary
Test yourself
Further reading
Wrapping up
Answers to self-assessment questions
Chapter 2
Chapter 3
Chapter 4
Chapter 5
Chapter 6
Chapter 7
Chapter 8
Chapter 9
Chapter 10
