Developers claim that using Scala helps to dig deep into Spark source code to easily access and implement new Spark features. Scala's interoperability with Java is its biggest attraction, as Java developers can easily get on the learning path by quickly grasping object-oriented concepts. Scala is a powerful programming language that offers developer-friendly features not available in Python. Scala is also great for low-level Spark programming and easy navigation directly to the underlying source code.
I'm working on a project called bebe that will hopefully provide the community with a secure, high-performance Scala programming interface. In short, Scala is my first choice of programming language for Spark projects and I will consider Python when the use case fits. You can use basic Scala programming features with the IntelliJ IDE and get useful features like type hints and compile-time checks for free. You will master the essential skills of the open source Apache Spark framework and the Scala programming language.
Many organisations favour the speed and simplicity of Spark, which supports many application programming interfaces (APIs) available from languages such as Java, R, Python and Scala. Scala offers many advanced programming features, but it is not necessary to use any of them when writing Spark code.