SomethingAbout
Architecture
Architecture
IS NOT
Patterns and/or Frameworks
Architecture
is set of constraints
Want to write good and maintainable code?
Tech Debt
GOTO Considered Harmful
but not lethal, and certainly not useless
var x = 2; // value and identifier
// ...
y = x ** 2; // state!Encapsulation
Law of Demeter
Separation of Concerns
Just different name for decomposition
DRY
Don't Repeat Yourself
Code is not reusable
Abstractions are reusable
Liskov
Substitution
Principle
Coupling & Cohesion
Single Responsibility Principle
Each class should have one and only one reason to change
class MerchantManager
{
public recalculateSalesLimit(merchant: Merchant): void
{
const salesForPreviousMonth = this.orders.salesForPreviousMonth(merchant);
const salesLimit = Math.max(
MIN_SALES_LIMIT,
salesForThisMonth * 1.5,
);
merchant.setLimit(salesLimit);
this.notifier.send(new SalesLimitUpdated(merchant, salesLimit));
}
}Not so good...
Dependency Inversion
Dependency Inversion
Inversion Of Control
Don't call us, we call you
Inversion of Control
Inversion of Control
