Modeling a future action

During modeling a business logic we have often a problem with properly highlighting a relevant future action. I mean relevant from a domain point of view. The most popular solution will be using a CLI command which will be executed by cron at a specific time. I think that this solution often hides a lot of business logic in an inappropriate place. Perhaps, there is a better way?

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An absolutely clean domain or just common sense

Nowadays, a concept like DDD is widely known and used by many programmers. Curious programmers read a lot about those practices in books written by Evans or Vernon or maybe have knowledge from conferences or blogs. As I saw many times, people are trying to be too much strict with these practices. Trying to make a domain completely clean is of course highly desired, but if you have a not very complex domain, and to have a completely clean domain you need to highly complicate the code around it (probably Infrastructure’s code) something is wrong, don’t you think? So you need to think about the return on investment. Is it worth having more work to do, and complex infrastructure code to just make your domain completely clean? In most cases probably it isn’t at all, only in projects with a highly complicated domain it will be necessary to define a core domain, and then perhaps making this core domain completely clean will make sense. However, not every place in your project will be perfect, you should invest your time only in the most important places. So in this article, I would like to write about using ORMs when approaching DDD which are often hated by many people.

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Unit testing tips by examples in PHP

In these times, the benefits of writing unit tests are huge. I think that most of the recently started projects contain any unit tests. In enterprise applications with a lot of business logic, unit tests are the most important tests, because they are fast and can us instantly assure that our implementation is correct. However, I often see a problem with good tests in projects, though these tests’ benefits are only huge when you have good unit tests. So in these examples, I will try to share some tips on what to do to write good unit tests.

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Docker hangs during build

Yesterday I had a strange problem with Docker during a build process. I use Linux Mint. I didn’t have enough space at the main system directory /. By default, Docker saves all data (images, volumes, etc.) in /var/lib/docker. Firstly I wanted to move this directory to the /home, but unfortunately, there was probably a problem with encryption, and Docker’s daemon couldn’t start properly. The second option was to move the directory to a hdd drive. But it also wasn’t a piece of cake (just Linux user normal day 😀 ).  

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Circuit Breaker

In most systems, we use remote calls. Many factors may have an impact on these remote calls e.g. network latency, server availability and so on. So we should assume that something can go wrong. These calls can be potential bottlenecks, we don’t want user waiting for the response from the server very long, because external API is very slow or not available. Also if we have a few services which communicate with each other we shouldn’t aggravate the situation when one of them has too much traffic and slow down significantly. So how to do it correctly?

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