Domain Driven Design
more than code
Who am I?
Damiano Petrungaro
Italy
source: www.vidiani.com
Tivoli (RM)
source: www.livitaly.com
Tivoli (RM)
source: www.romaest.org
Tivoli (RM)
source: www.tivolitouring.com
Tivoli (RM)
source: www.confinelive.it
Tivoli (RM)
source: www.greenparkmadama.it
Me everyday:
What is DDD ?
Domain Driven Design is an approach to software development for complex needs by connecting the implementation to an evolving model.
It is not about code.
It is not, only, about code.
Strategic Design
Tactical Design
The strategic design is the one in which you and the domain experts analyze a domain, define its boundaries, and look for the best way to let communicate different boundaries.
The tactical design describes a group of patterns to use to shape as code the invariants and models defined in a domain analysis that is often (hopefully) driven by the strategic design.
Give a set of tools that you can use to solve common organizational problems.
Goal of this talk:
There will be no code.
At all.
Everything starts with an idea
Let's build a new product!
Let's code it!
Understand the problem
Contexts
The circumstances that form the setting for an event, statement, or idea, and in terms of which it can be fully understood.
" The first result of a Google search
Why context matters?
Office
Shower
Be naked in:
Nude Beach
Non-Nude Beach
Context may looks similar but...
Be naked in:
How does it relate to DDD?
Context influences behaviors, the language and the meaning of the words
Polysemy
Star
The
ubiquitous language
- Clear communication
- Teams
- Customers & CC
- Onboarding
- Code express behavior
Bounded Context
It is part of the Strategic Pattern of the DDD literature and it represents a logical boundary where the rules of a sub-domain are applied and make your context unique
Split the problem
Sub-Domains
Core: is a part of the business that is of primary importance to the success of the organization.
Supporting: is a part of the business that is essential, but yet not Core.
Generic: is a part of the business that looks like a supporting subdomains but it is not specialized.
A domain visualization
Context map
Bounded contexts are isolated.
But they need to communicate.
9 ways to communicate across contexts
- Partnership
- Shared Kernel
- Customer-Supplier Development
- Conformist
- Anticorruption layer
- Open Host Service
- Published Language
- Separate ways
- Big ball of mud
Clear dependencies
Clear relationship
Clear contracts
Recap
- Study the problem before solving it
- Identify sub-domains and scope their contexts
- Define a common language to use in each sub-domain
- Find a way to communicate with the other sub-domains defining contracts, if needed
That's it folks!
fun fact: "/giphy damiano"
Domain Driven Design
By Damiano Petrungaro
