$ go get github.com/gin-gonic/gin
go: github.com/gin-gonic/[email protected]: Get "https://proxy.golang.org/github.com/gin-gonic/gin/@v/v1.9.1.mod": dial tcp 172.217.160.81:443: i/o timeout
# 配置国内代理
go env -w GOPROXY=https://goproxy.cn,direct
go env -w GOSUMDB=sum.golang.org
# 或者配置多个代理
go env -w GOPROXY=https://goproxy.cn,https://goproxy.io,direct
# 对于私有仓库，配置GOPRIVATE
go env -w GOPRIVATE=*.corp.example.com,rsc.io/private
$ go run main.go
go: cannot find main module, but found .git/config in /path/to/project
# 初始化模块
go mod init project-name
# 如果是现有项目
go mod init github.com/username/project-name
# 整理依赖
go mod tidy
go: github.com/example/[email protected]: parsing go.mod:
module declares its path as: github.com/example/other
but was required as: github.com/example/package
# 1. 检查go.mod文件中的依赖声明
cat go.mod
# 2. 使用正确的模块路径
go mod edit -replace github.com/example/package=github.com/example/[email protected]# 3. 或者直接修改import语句使用正确的路径
# import "github.com/example/other"
# 4. 清理并重新下载依赖
go clean -modcache
go mod download
$ go build
# github.com/example/project
./main.go:10:2: undefined: someFunction
$ GODEBUG=gctrace=1 ./myapp
gc 1 @0.001s 2%: 0.018+0.46+0.071 ms clock, 0.14+0.12/0.28/0.41+0.57 ms cpu, 4->4->2 MB, 5 MB goal, 8 P
gc 2 @0.002s 3%: 0.019+0.45+0.069 ms clock, 0.15+0.13/0.29/0.42+0.55 ms cpu, 4->4->2 MB, 5 MB goal, 8 P
// 1. 对象池复用
package main
import "sync"
var bufferPool = sync.Pool{
New: func() interface{} {
return make([]byte, 1024)
},
}
func processData(data []byte) {
// 从池中获取buffer
buffer := bufferPool.Get().([]byte)
defer bufferPool.Put(buffer) // 使用完后放回池中
// 使用buffer处理数据
copy(buffer, data)
// ...
}
// 2. 预分配切片容量
func buildSlice(size int) []string {
// 预分配容量，避免多次扩容
result := make([]string, 0, size)
for i := 0; i < size; i++ {
result = append(result, fmt.Sprintf("item-%d", i))
}
return result
}
// 3. 使用strings.Builder代替字符串拼接
func buildString(items []string) string {
var builder strings.Builder
builder.Grow(len(items) * 10) // 预分配容量
for _, item := range items {
builder.WriteString(item)
builder.WriteString(", ")
}
return builder.String()
}
$ go run -race main.go
==================
WARNING: DATA RACE
Write at 0x00c000014088 by goroutine 7:
main.increment()
/path/to/main.go:15 +0x44
Previous read at 0x00c000014088 by main goroutine:
main.main()
/path/to/main.go:25 +0x88
// 问题代码
package main
import (
"fmt"
"time"
)
var counter int
func increment() {
counter++ // 数据竞争
}
func main() {
for i := 0; i < 10; i++ {
go increment()
}
time.Sleep(time.Second)
fmt.Println(counter)
}
// 解决方案1：使用互斥锁
package main
import (
"fmt"
"sync"
"time"
)
var (
counter int
mutex sync.Mutex
)
func increment() {
mutex.Lock()
defer mutex.Unlock()
counter++
}
// 解决方案2：使用原子操作
package main
import (
"fmt"
"sync/atomic"
"time"
)
var counter int64
func increment() {
atomic.AddInt64(&counter, 1)
}
// 解决方案3：使用channel
package main
import "fmt"
func main() {
counter := make(chan int, 1)
counter <- 0
done := make(chan bool)
for i := 0; i < 10; i++ {
go func() {
count := <-counter
count++
counter <- count
done <- true
}()
}
for i := 0; i < 10; i++ {
<-done
}
fmt.Println(<-counter)
}
$ go run main.go
fatal error: all goroutines are asleep - deadlock!
goroutine 1 [chan receive]:
main.main()
/path/to/main.go:10 +0x6f
exit status 2
$ go test -cover ./...
ok github.com/example/project/service 0.123s coverage: 45.2% of statements
ok github.com/example/project/handler 0.089s coverage: 32.1% of statements
$ time go test ./...
ok github.com/example/project/service 45.123s
ok github.com/example/project/handler 32.456s
real 1m30.123s
user 0m15.678s
sys 0m2.345s
// 1. 使用测试分类
package service
import (
"testing"
"time"
)
// 快速单元测试
func TestUserService_ValidateUser(t *testing.T) {
// 纯逻辑测试，无外部依赖
service := &UserService{}
valid := service.ValidateUser(&User{Name: "John", Email: "[email protected]"})
assert.True(t, valid)
}
// 集成测试（使用build tag）
// +build integration
func TestUserService_DatabaseIntegration(t *testing.T) {
// 需要数据库的测试
db := setupTestDB()
defer cleanupTestDB(db)
repo := NewUserRepository(db)
service := NewUserService(repo)
// 测试逻辑
}
// 2. 使用并行测试
func TestUserService_Parallel(t *testing.T) {
tests := []struct {
name string
input string
expected string
}{
{"test1", "input1", "output1"},
{"test2", "input2", "output2"},
{"test3", "input3", "output3"},
}
for _, tt := range tests {
tt := tt // 捕获循环变量
t.Run(tt.name, func(t *testing.T) {
t.Parallel() // 并行运行
result := processInput(tt.input)
assert.Equal(t, tt.expected, result)
})
}
}
// 3. 使用测试缓存和短路
func TestUserService_WithTimeout(t *testing.T) {
if testing.Short() {
t.Skip("Skipping test in short mode")
}
// 耗时测试逻辑
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
// 使用context控制测试时间
}
// 运行命令
// go test -short ./... # 跳过耗时测试
// go test -tags=integration ./... # 运行集成测试
// go test -parallel 4 ./... # 并行运行测试
$ go test ./...
--- FAIL: TestUserAPI (0.12s)
user_test.go:25: Expected status 200, got 500
user_test.go:26: Database connection failed: dial tcp 127.0.0.1:3306: connect: connection refused
