The Log Book of Manuel Kießling
The Log Book of Manuel Kießling
Covers topics on architecting, building, deploying and running software and systems for the web based on open source tools with lean methodologies.
At Galeria.de, we learned the hard way that it's critical to understand the inner workings of the distributed masterless database Cassandra if one wants to experience good performance during reads and writes. This post describes some of the details of how Cassandra works under the hood, and shows how understanding these details helps to anticipate which use patterns work well and which don't.
For one of my current projects, I needed to gain full control over the request-body-to-case-class-object transformation of my Scala Play2 controller action. Here's the solution I came up with.
I recently played around with graphs and tried to implement Depth-First Search in a functional and recursive way. Here is what I learned.
Passing an array when declaring a defined type automatically evaluates the defined type once for each element of the array, but care must be taken if no array is declared in the Hiera structure for a given target system.
Play 2.4 supports Compile Time Dependency Injection. This post describes how to inject your own Cassandra repository object into a controller at compile time, while also initializing and closing a Cassandra connection session during application startup and shutdown, and how to mock the repository in the non-integration tests.