Making choices for our application

Because this is the point to choose a programming language for microservices and applications in general, we will apply this knowledge to select which programming language we use in each area of our service.

We know that our news portal has the following areas:

• SportNewsService
• PoliticsNewsService
• FamousNewsService
• RecommendationService
• UsersService

Given our fields of business, we can divide them by similarity of features. SportNewsService, PoliticsNewsService, and FamousNewsService have similar behavior. These microservices are news providers and are more focused on the consumption of data than receiving information.

These microservices may have an identical starting stack, which does not mean they should always be identical or that they need evolve in the same direction. Regarding the programming language, performance is not as crucial, but the speed of change and implementation of new features is crucial.

RecommendationService is very different from the other microservices. There is no direct interaction between the end user and the application. Nor is there a direct interaction between the editorial area and this software. RecommendationService is a support microservice; there are other microservices and all the interactions and operations are on  the technical side. Loading and interaction occur completely asynchronously, but processing will certainly be higher than in other microservices. However, this is not a real-time application.

UserServices is a microservice with dynamic interaction on all sides, both for the end user as well as the editorial layer. The information from UserService may also be consumed by the other microservices such as RecommendationService. It is noteworthy that on this layer, caches can be dangerous, providing wrong information if they are not correctly invalidated. As UserService is a microservice that supports a direct relationship with the internet, it leads us to a programming language that has the speed of response for requests, processing speed, simplicity in implementing features, and good asynchrony APIs.

With the characteristics of each sector in mind, it is the time to think in a completely practical way to select a programming language that applies to each microservice. Let's consider each of the five aspects mentioned at the beginning of the chapter associated with the nature of the issues.

Comparing programming languages is complex, but in this case, we need to make choices. Many languages could be compared. However, for our application, we have chosen five for the comparison based on popularity, personal experience, documentation, and actual cases of applicability. The languages are Java, C#, Python, JavaScript, and Go.