7hoenix

7hoenix

Real-World Event Sourcing:

@autodidaddict

Real World Event Sourcing: Page 105 of version 3 (PDF)

Inconsistent descriptions around whether Aggregates can process events or only commands.

An aggregate’s internal state can change by replaying events that predate the newly deployed aggregate, but that doesn’t alter the timeline, so it’s allowed.

The book seems to not be internally consistent with if aggregates are meant to process events or only commands.

Sometimes the book says that Aggregates execute commands to produce events (with Process Managers doing the inverse), but then quotes like this trickle through and I get a little confused.

I did look at the Commanded api, and it doesn’t seem to provide a way to process events in aggregates.

First Post!

swrenn

swrenn

Hello. I’m also reading this book. I believe aggregates consume events to build internal state and then use that state to vet commands. It looks like apply/2 serves this purpose. There’s an example here.

Popular Pragmatic Bookshelf topics Top

Razor54672
The answer to 3rd Problem of Chapter 5 (Making Choices) of “Practical Programming, Third Edition” seems incorrect in the given answer ke...
New
telemachus
Python Testing With Pytest - Chapter 2, warnings for “unregistered custom marks” While running the smoke tests in Chapter 2, I get these...
New
johnp
Hi Brian, Looks like the api for tinydb has changed a little. Noticed while working on chapter 7 that the .purge() call to the db throws...
New
herminiotorres
Hi @Margaret , On page VII the book tells us the example and snippets will be all using Elixir version 1.11 But on page 3 almost the en...
New
raul
Hi Travis! Thank you for the cool book! :slight_smile: I made a list of issues and thought I could post them chapter by chapter. I’m rev...
New
joepstender
The generated iex result below should list products instead of product for the metadata. (page 67) iex> product = %Product{} %Pento....
New
New
leonW
I ran this command after installing the sample application: $ cards add do something --owner Brian And got a file not found error: Fil...
New
akraut
The markup used to display the uploaded image results in a Phoenix.LiveView.HTMLTokenizer.ParseError error. lib/pento_web/live/product_l...
New
mert
AWDWR 7, page 152, page 153: Hello everyone, I’m a little bit lost on the hotwire part. I didn’t fully understand it. On page 152 @rub...
New

Other popular topics Top

Exadra37
Please tell us what is your preferred monitor setup for programming(not gaming) and why you have chosen it. Does your monitor have eye p...
New
PragmaticBookshelf
Design and develop sophisticated 2D games that are as much fun to make as they are to play. From particle effects and pathfinding to soci...
New
Margaret
Hello content creators! Happy new year. What tech topics do you think will be the focus of 2021? My vote for one topic is ethics in tech...
New
PragmaticBookshelf
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
New
PragmaticBookshelf
Author Spotlight: Karl Stolley @karlstolley Logic! Rhetoric! Prag! Wow, what a combination. In this spotlight, we sit down with Karl ...
New
PragmaticBookshelf
Author Spotlight: Tammy Coron @Paradox927 Gaming, and writing games in particular, is about passion, vision, experience, and immersio...
New
PragmaticBookshelf
A Ruby-Centric Chat with Noel Rappin @noelrappin Once you start noodling around with Ruby you quickly figure out, as Noel Rappi...
New
CommunityNews
A Brief Review of the Minisforum V3 AMD Tablet. Update: I have created an awesome-minisforum-v3 GitHub repository to list information fo...
New
sir.laksmana_wenk
I’m able to do the “artistic” part of game-development; character designing/modeling, music, environment modeling, etc. However, I don’t...
New
AstonJ
If you’re getting errors like this: psql: error: connection to server on socket “/tmp/.s.PGSQL.5432” failed: No such file or directory ...
New

Sub Categories: