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Initial thoughts post the event modeling workshop
I attended the first ever event modeling conference in Munich this week, hosted by Martin Dilger. You can find out more about the event here:https://www.linkedin.com/feed/update/urn:li:activity:7382309099826221056/ I got into event modeling because I was looking into the various tools available for visualizing requirements that’s understandable by both business and development. I had been looking at Event — read more
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Modeling a shipping cost calculator using Template and Strategy design patterns
I wanted to make a simple application of how an event stormed model could be possibly taken into implementation. I took inspiration from a previous industry I worked in because logistics is really one of those good domains where there is lots of options for interesting modeling. The scenario I selected is an MVP for — read more
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Implementing a Raffle System using event modeling and event sourcing
A few weeks ago, I wanted to try out the process of event modeling for designing and then building a simple application. I had picked a simplified raffle application and ended up drawing out the following features: I had decided to prioritize some over others due to the lack of time. Things got busy in — read more
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Bugs with Misleading Messages
Are probably the worst. I was getting the following error message when trying to upload to Azure Blob Storage but only for some of the documents we were syncing. Turns out, blob meta data have a few requirements: • Metadata keys must be alphanumeric and can include dashes (-) and underscores (_).• Keys cannot contain — read more
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Persisting changes as Events
Now we have implemented the persistence of our domain and read models, we can start to revisit the implementation so that we can switch over to an event-sourced domain model instead. We need a way to store and retrieve new events so I have added a private property and exposed a read-only collection as well — read more
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Implementing persistence and setting up integration tests along the way
So far, we’ve used fake repositories in our tests, now it’s time to have an actual implementation of how we want to persist our data. The goal is to be able to add entries when our application is running, and even if the application restarts, it should still have this data. In order to be — read more
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Teach Your (Domain) Models How to Fish (And Scale)
“Give a man a fish and you feed him for a day. Teach him how to fish and you feed him for a lifetime“ I feel like we developers have an opportunity to really take this quote to heart. As developers we like giving computers instructions. We retrieve an object that we want to update, — read more
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TDD of the Domain Model, building a registration app
In the last post we did a TDD walk through building the application but we didn’t really get into the event sourcing side of things, which was the original intent of this series. I only recently read about Event Sourcing through the book Understanding Eventsourcing by Martin Dilger. It goes into a lot of detail, — read more
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Trying out TDD, building a registration app
From the last post, I decided to to rename my Aggregate to Individual to align more with a ubiquitous language, a key component of DDD. 😉 I also updated the read model to contain a list of multiple batch statistics so the api would return a single object and not an array of objects. One — read more
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Set up MockServiceWorker for easier front-end development
This week I got the opportunity to introduce the Mock Service Worker library into the user story I was working on. Building a fronted app that should behave differently depending on the response we get from the API gets challenging if you always have to rely on a live API. I first used this library — read more