Travis Stevens- Using GADTs to create a “Full Stack”, Runtime Gen. Scaffolding Lib in Scala- λC 2019

Описание: Using GADTs to create a “Full Stack”, Runtime Generated Scaffolding Library in Scala

We will learn how the Scala library “Bones” uses Generalized Abstract Data Types to define a schema and utilize different interpreters to create HTTP routes, database tables, documentation, and web application code based on the schema. The interpreter output is kept in sync if the schema changes. Generalized Abstract Data Types (GADTs) give us a strategy to decouple the description of data from code that is executed. This decoupling allows us to create multiple interpreters for a GADT algebra and provides some guarantees that different interpreters are working with the same data structure and are kept in sync if the data structure changes, or if a new data type is introduced. Using this technique, we will learn how to code multiple interpreters in order to create a full stack web application where the interpreters can be reused for variable Scala data structures.

The talk outline is as follows:

Demo to give context as to the intent of using GADTs

GADT Basics

GADT Data Type

DSL

Interpreters

basics

interpreters returning functions

Building a JSON deserializer interpreter using the Argonaut JSON library

Validation as a GADT

Using the Shapeless library for more complex data structures.

Interpreters for full stack REST Applications including

Data exchange formats: JSON, BJSON and Protobuf

Swagger Documentation

Server Side definitions

Client Side React Applications