go-dev

Go Development Standards

References: Effective Go, Go Code Review Comments, uber-go/guide

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Toolchain

goimports -w .                    # 格式化并整理 import
go vet ./...                      # 静态分析
golangci-lint run                 # 综合检查
go test -v -race -cover ./...     # 测试（含竞态检测和覆盖率）

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Naming Conventions

Type	Rule	Example
Package name	Lowercase words, no underscores	user, orderservice
Variables/Functions	CamelCase, consistent casing for abbreviations	userID, HTTPServer
Constants	Exported use CamelCase, unexported may use CamelCase or all caps	MaxRetryCount
Interfaces	Single-method interfaces use method name + er	Reader, Writer

Prohibited: common, util, base and other meaningless package names

---

import order

import (
    "context"           // 标准库
    "fmt"

    "github.com/gin-gonic/gin"  // 第三方库

    "project/internal/model"     // 项目内部
)

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Error Handling

Errors must be handled, cannot be ignored:

// ✅ 好：添加上下文
if err != nil {
    return fmt.Errorf("failed to query user %d: %w", userID, err)
}

// ❌ 差：忽略错误
result, _ := doSomething()

Error wrapping: use %w to preserve the error chain, use errors.Is() / errors.As() to check

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Concurrent Programming

Basic principles:

• Prefer channel communication
• Before starting a goroutine, consider: who will wait for it? How will it be stopped?
• Use context.Context to control the lifecycle

// ✅ 好：使用 context 控制
func process(ctx context.Context) error {
    done := make(chan error, 1)
    go func() { done <- doWork() }()

    select {
    case err := <-done:
        return err
    case <-ctx.Done():
        return ctx.Err()
    }
}

Data race: use go test -race to detect

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Testing Standards

// 表驱动测试
func TestAdd(t *testing.T) {
    tests := []struct {
        name     string
        a, b     int
        expected int
    }{
        {"positive", 1, 2, 3},
        {"zero", 0, 0, 0},
    }

    for _, tt := range tests {
        t.Run(tt.name, func(t *testing.T) {
            got := Add(tt.a, tt.b)
            if got != tt.expected {
                t.Errorf("Add(%d, %d) = %d, want %d", tt.a, tt.b, got, tt.expected)
            }
        })
    }
}

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Performance Optimization

Pitfall	Solution
Concatenating strings in a loop	Use strings.Builder
Slice not preallocated	make([]T, 0, cap)
N+1 query	Batch query + preload
Unlimited concurrency	Use semaphore or worker pool
Raw SQL alias uses a reserved word	Avoid using year_month/order/status/rank and other MySQL reserved words as aliases

# 性能分析
go test -cpuprofile=cpu.prof -bench=.
go tool pprof cpu.prof

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Project Structure

project/
├── cmd/                    # 可执行文件入口
├── internal/               # 私有代码
│   ├── handler/
│   ├── service/
│   ├── repository/
│   └── model/
├── pkg/                    # 公共代码
├── go.mod
└── go.sum

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Detailed References

File	Content
references/go-style.md	Naming conventions, error handling, concurrency, testing, performance
references/date-time.md	Date addition/subtraction, billing period calculation, AddDate overflow handling

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