# Developing Microservice-Based Applications Using the Silvera Domain-Specific Language
## 3 Silvera
### Silvera Concrete Syntax
#### 3.3.2 Service Registry Declaration
 & \\ \hline User & 19 & 159 & 8 & 77 & 0 & 236 & 8 & 244 & 96.72 \\ \hline Meal & 26 & 204 & 10 & 77 & 0 & 154 & 10 & 164 & 93.9 \\ \hline Storage & 16 & 142 & 9 & 77 & 0 & 154 & 9 & 163 & 94.48 \\ \hline Order & 37 & 523 & 27 & 81 & 0 & 162 & 27 & 189 & 88.71 \\ \hline EmailNotifier & 24 & 379 & 59 & 81 & 4 & 162 & 63 & 225 &the following characteristics: functional suitability, usability, reliability, maintainability, productivity, extendability, compatibility, expressiveness, reusability, and integrability. The evaluation is based on the methodology presented by [PERSON] et al. [60], whereas reporting is based on work presented by [PERSON] et al. [61]. ### Scoping

The scope of the experiment was set by defining its goals [60]. Here we follow the GQM template for goal definition, originally presented by [PERSON] and [PERSON] [62]. The goal of the study was to analyze Silvera for the purpose of evaluation with respect to the following DSL quality characteristics: functional suitability, usability, reliability, productivity, extendability, and expressiveness. The perspective is from the researcher's point of view. The study was run using students and software developers with experience in MSA or software architectures in general. ### Hypotheses

Before we shared the survey with participants, we defined the following hypotheses. **Hypothesis 1**. : _Silvera is not appropriate for the specification of MSA. Alternative Hypothesis \(H1_{1}\): Silvera is appropriate for the specification of MSA._

**Hypothesis 2**. : _Silvera language elements are not understandable. Alternative Hypothesis \(H1_{2}\): Silvera language elements are understandable._

**Hypothesis 3**. : _The concepts and notation of the Silvera language are not learnable and rememberable. Alternative Hypothesis \(H1_{3}\): The concepts and notation of the Silvera language are learnable and rememberable._

**Hypothesis 4**. : _Silvera is not appropriate for users' needs when developing MSA. Alternative Hypothesis \(H1_{4}\): Silvera is appropriate for users' needs when developing MSA._

**Hypothesis 5**. : _Silvera does not protect users against making errors. Alternative Hypothesis \(H1_{5}\): Silvera protects users against making errors._

**Hypothesis 6**. : _Silvera does not shorten the time needed to develop MSAs. Alternative Hypothesis \(H1_{6}\): Silvera shorten the time needed to develop MSAs._

**Hypothesis 7**. : _Silvera does not reduce the number of human resources used to develop MSAs. Alternative Hypothesis \(H1_{7}\): Silvera reduces the number of human resources used to develop MSA._

**Hypothesis 8**. : _Silvera does not provide one and only one good way to express every concept of interest. Alternative Hypothesis \(H1_{8}\): Silvera provides one and only one good way to express every concept of interest._

**Hypothesis 9**. : _Each construct in Silvera is not used to represent exactly one distinct concept in the domain. Alternative Hypothesis \(H1_{9}\): All constructs in Silvera represent exactly one distinct concept in the domain._

**Hypothesis 10**. : _Silvera contains conflicting elements. Alternative Hypothesis \(H1_{10}\): Silvera does not contain conflicting elements._

Hypothesis 1 tests the _appropriateness_ of Silvera. _Appropriateness_ is a sub-characteristic of the _functional suitability_. Functional suitability refers to the degree to which a DSL is fully developed [13]. DSL should contain all necessary functionality from the domain and should not contain nor include functionality that is not in the domain [13]. Hypotheses 2-4 test the _comprehensibility_, _learnability_, and _likeability/user perception_, respectively. In FQAD, these characteristics are sub-characteristics of _usability_, which is defined as \"the degree to which a DSL can be used by specified users to achieve specified goals\" [13]. Hypothesis 5 tests the _reliability_ of Silvera.