Transaction Script/ Use Case pattern

What it is?

• Domain logic goes in here.

  • Single procedure for each action(http request) that a user might want to do

• Procedural in nature

• Takes input from presentation layer

  • validated or changed to be able to used here

• Flow of the process takes place

  • processes input with validations and calculations, stores data in the database, and invokes any operations from other systems

• Dependencies from outer layers are injected here using the interface

• The response is what is processed by the presentation layer

• avoid calls to presentation layer

  • Should not interact again

Advantages

• easy to follow, clear structure

• Easy to use several depenencies to perform actions

• useful for simple domain logic

Disadvantages

• can grow in complexity, and become big

  • dont want to extract to much logic as it adds layer of indirection

• Duplication can occur between different transaction scripts

Other

• Can use command pattern for this