Implementing Active Record with Slick

Step by step demo on how to implement the Active Record Pattern with Slick

This project is composed of an initial state and 8 steps.

Groll

The groll sbt plugin is enabled for this project. You can navigate through the steps by simply running 'groll next' or 'groll prev'. NOTE: all uncommitted code is lost when you move from one step to the next using groll.

run 'groll initial' rewind to the 'Initial state'.

Initial state

Defines 'Conference' model and Slick table mapping.

Step 1

Demonstrates the available options in Slick to insert an Entity and assign the newly generated Id to the model class.

Step 2

Defines IdTable with a well-known id:Column[Long]. This is the first building block to reduce the boilerplate.

Step 3

Introduces the ActiveRecord trait and adds a 'save' method to the model using the pimp-my-library pattern.

Step 4

Shows other advantages of having well-known id:Column (findById, delete, filterById)

Step 5

Makes id:Column type generic and shows what have to be done to achieve it (ie: usage of BaseColumnType in Context Bound).

Step 6

Introduces Entity trait reducing the signature of IdTable and IdTableQuery via type projection of Entity#Id type.

Step 7

Usage of Cake Pattern to allow driver swap.

Step 8

Further boilerplate reduction by using Monocle Lens to eliminate 'withId' and 'extractId'.
Minimalistic Entity trait (only defines a type alias for Id).