CONVENTION.md

Go Conventions

1. Naming Conventions

1.1 Package Naming

• Use lowercase and short, meaningful names.
• Avoid underscores (_) or mixed caps.

package customer

1.2 Struct Naming

• Use PascalCase.
• Name structs explicitly and meaningfully.

type CustomerManager struct {
    // Fields
}

1.3 Function Naming

• Use PascalCase for exported functions.
• Use camelCase for unexported functions.

func CalculateTotal() int {
    return 0
}

func processOrder() {
    // Internal function
}

1.4 Variable and Field Naming

• Use camelCase for local variables.
• Use PascalCase for exported struct fields.
• Use short, clear, and meaningful names.

var customerName string

// Inside a struct

type Customer struct {
    Name  string  // Exported field
    email string  // Unexported field
}

1.5 Constant Naming

• Use PascalCase for exported constants.
• Use camelCase for unexported constants.

const MaxRetryCount = 5
const apiKey = "12345"

1.6 Interface Naming

• Use -er suffix when possible.

type Reader interface {
    Read(p []byte) (n int, err error)
}

type CustomerRepository interface {
    Save(customer Customer) error
}

1.7 Error Naming

• Define errors using errors.New.
• Use Err prefix.

var ErrNotFound = errors.New("not found")

2. Comments and Documentation

2.1 Using GoDoc Comments

• Use // for single-line comments.
• Use full sentences starting with the function name.

// CustomerManager handles customer operations.
type CustomerManager struct {}

// AddCustomer adds a new customer.
func (cm *CustomerManager) AddCustomer(c Customer) {
    // Implementation
}

3. Unit Tests

3.1 Using Testing Package

• Use Go's built-in testing package.
• Name test functions as Test[Function].
• Use *_test.go suffix for test files.

package customer_test

import (
    "testing"
    "github.com/stretchr/testify/assert"
)

func TestAddCustomer(t *testing.T) {
    cm := customer.CustomerManager{}
    c := customer.Customer{Name: "John Doe"}
    
    err := cm.AddCustomer(c)
    
    assert.NoError(t, err)
}