Getting Started: Event Sourcing in .NET

Get started with Event Sourcing in .NET

About This Course

Event Sourcing is a persistence design pattern. It is often mentioned alongside CQRS and DDD. In short, it is the practice of storing the events that lead up to the current state instead of storing the state itself, as one would do in a CRUD system with a normalized database. The assumption is that it is always possible to re-create the state from the events, but not the other way around. Especially when Event Sourcing is combined with CQRS architecture, it enables a whole new way of thinking about data in your applications. It enables point-in-time data and the possibility to process old events against new features retroactively. In this course, the Event Sourcing principles and patterns are introduced, and we build an entire CQRS application from scratch to demonstrate how things piece together. We are not using a ready-made framework for this, but we are trying to take away the magic by building our own. At the end of this course, you should be familiar with event sourcing and how it fits with CQRS architecture.

Course Curriculum

4h 1m 8 sections

Welcome

00:50 Free preview

What will you learn in this course?

01:10 Free preview

Who is the course for and prerequisites

01:39 Free preview

What is Event Sourcing?

06:05

Commands vs Events

03:39

Future, Present & Past

07:03

The relationship with DDD

03:37

Events, streams & aggregates

04:49

The command handler life cycle

04:03

CQRS architecture

06:42

Section recap

00:50

Introduction to our domain

06:33

Modelling Events & Commands

08:52

Value Types in commands & events

14:21

Making root entities

05:16

Building Command Handlers

19:23

Adding a Command Router

07:29

An exercise for you to make

01:49

Section recap

00:40

Introduction to the test base class

06:13

Writing event sourced tests

05:17

Making our tests more read readable

08:24

Another exercice

00:56

Section recap

00:42

What are we going to build?

02:32

A look at our starting point

06:24

Building a simple event store

08:54

Building a command API

04:10

Alternate API approaches

03:47

Finalizing & running our API

06:19

Exercise time again!

00:27

Section recap

00:40

Checking out the read API

07:06

Querying aggregate data

03:35

Building a projection system

29:38

Exercise

02:28

Section recap

00:42

The typical UI pattern

04:06

Introducing the SignalR Hub

06:41

Publishing our events over SignalR

09:48

A final exercise

00:45

Section recap

01:18

What can our system now do?

09:48

Beyond this course

04:03

Conclusion

00:55

Course Details

Level Getting Started

Duration

Rating

$89.99

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Meet Your Instructor

Hannes Lowette

Hannes Lowette

With 20 years in .NET development, Hannes has always been passionate about performance, databases, distributed systems and large-scale applications. When it comes to architecture, his opinions have become a bit more nuanced, and the "it depends" card, however boring, gets played in many technical discussions. Hannes has always had a passion for sharing knowledge. It doesn't matter whether it is one-to-one while pair programming, on a conference stage giving a talk or when he's helping people succeed in their careers as a coach. In his free time, when he's not building LEGO® castles with his three kids, he likes to stream his guitar building on Twitch and spends too much time playing online chess and doing all-around geeky stuff. You can always lure him into a chat over a glass of great Whisky.

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