Learn how to create, test, and compare the back-end HTTP services in Scala.

Become a Scala Developer

In this module, we will explore the functional aspects of Scala. We will start by looking at a small use case. We will then learn the difference between pure and impure implementations by looking into referential transparency and how functional programming relies on it. We will then gradually implement the use case in both pure and impure ways. Moving ahead, we will simultaneously build, test, and document the implementations and point out the tools required along the way. By the end of this module, we will have a substantial understanding of how these techniques work, their pros and cons, and how pure implementation can be more robust.

Pure Functional HTTP APIs in Scala

```
Type StudentName = String Refined NonEmpty
```

```
Type StudentName = String Refined MatchesRegex[W."^[a-zA-Z ]*$".T]
```

Suppose we were to make another service involving student records. What is the best possible option for a model of a student's name?

*Remember, names are not necessarily unique.*

Suppose we were to make another service involving student records. What is the best possible option for a model of a student’s name?
Remember, names are not necessarily unique.

```
Type StudentNames = NonEmptyList[StudentName]
```

```
Type StudentNames = List[StudentName]
```

```
Type StudentNames = NonEmptySet[StudentName]

Adding to the service mentioned in Q1, we want a model for a list that holds all student names.

*Remember, names are not necessarily unique.*

Adding to the service mentioned in Q1, we want a model for a list that holds all student names.
Remember, names are not necessarily unique.

A database layer should provide:

1) Programmatic access to a database
2) One table for every main data type
3) Ability to manage database changes

A database layer should provide:
<ol>
<li>Programmatic access to a database</li>
<li>One table for every main data type</li>
<li>Ability to manage database changes</li>
</ol>

Test your knowledge and understanding by taking a quiz on impure service implementation.

Introduction

Impure Implementation

Pure Implementation

Testing Impure Services

Testing Pure Services

Benchmarks

Documentation

Conclusion

Quiz on Impure Service Implementation