Learn Encapsulating Behavior with Packages | Encapsulation and Interfaces

Swipe to show menu

Understanding how to organize your backend Go code is essential for building maintainable and robust systems. Go uses packages to group related code together, providing a clear structure and natural boundaries for encapsulation. A package in Go is simply a directory containing one or more .go files, all starting with the same package declaration. By convention, each package should focus on a single responsibility or domain area, such as database, http, or auth. This modular approach makes it easy to reason about, test, and reuse your code. In backend projects, you typically create packages for core components—such as data storage, business logic, and API handling—ensuring each part of your application is well-organized and separated from others.

database/database.go

main.go


              12345678910111213141516
            
package database

type Database struct {
    connectionString string
}

// New creates a new Database instance.
func New(connStr string) *Database {
    return &Database{connectionString: connStr}
}

// Connect simulates connecting to a database.
func (db *Database) Connect() string {
    return "Connected to: " + db.connectionString
}

By placing the Database struct and its methods inside a separate database package, you control what is accessible from outside the package. Only exported names—those starting with a capital letter—can be used by other packages. This boundary prevents unrelated parts of your codebase from depending on internal implementation details, reducing the risk of accidental misuse. Encapsulation at the package level encourages you to expose only the minimal interface needed, hiding configuration, helper functions, or internal logic. This approach not only keeps your codebase cleaner but also makes it easier to test and refactor individual modules without affecting the rest of your system.

Everything was clear?

Thanks for your feedback!

Section 2. Chapter 2

Ask AI

Ask anything or try one of the suggested questions to begin our chat

Section 2. Chapter 2