背景介绍 在Go语言中处理HTTP请求时，我们经常需要多次读取响应体(Response Body)的内容。然而，默认情况下Response Body只能被读取一次，这是因为它实现了io.ReadCloser接口，读取完毕后数据就会被消费掉。本文将介绍一个优雅的解决方案。 问题描述 假设我们有以下场景： 需要在日志中记录API的响应内容 需要对响应内容进行多次处理 需要在中间件中查看响应内容，同时不影响后续处理 解决方案 我们可以使用io.TeeReader来实现响应体的复制，这样就能多次读取相同的内容。以下是具体实现： package main import ( "bytes" "fmt" "io" "net/http" ) func DupReadCloser(reader io.ReadCloser) (io.ReadCloser, io.ReadCloser) { var buf bytes.Buffer tee := io.TeeReader(reader, &buf) return io.NopCloser(tee), io.NopCloser(&buf) } func DupResponseBody(resp *http.Response) ([]byte, error) { var buf io.ReadCloser resp.Body, buf = DupReadCloser(resp.Body) data, err := io.ReadAll(resp.Body) if err != nil { return nil, err } resp.Body = buf return data, nil } 代码解析 DupReadCloser函数：接收一个io.……

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将 struct 中的string 字段进行 trim func trimSpace(any interface{}) { ov := reflect.ValueOf(any) if ov.Kind() == reflect.Ptr && !ov.IsNil() { ov = ov.Elem() } ot := reflect.TypeOf(any) if ot.Kind() == reflect.Ptr { ot = ot.Elem() } for i := 0; i < ot.NumField(); i++ { field := ov.Field(i) if field.Kind() == reflect.Ptr { if field.Elem().Kind() == reflect.Struct { trimSpace(field.Interface()) continue } field = field.Elem() } if field.CanInterface() && field.IsValid() { if field.……

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支持不同格式之间的转换 支持图片像素的压缩以及拉长 package main import ( "bytes" "errors" "fmt" "image" "image/jpeg" "image/png" "io/ioutil" "os" "golang.org/x/image/draw" _ "golang.org/x/image/webp" // for RegisterFormat ) type imageHelper struct { img image.Image fileName string format string scale draw.Scaler } func NewImageHelper(fileName string, scale ...draw.Scaler) *imageHelper { var s draw.Scaler if scale == nil { s = draw.ApproxBiLinear } else { s = scale[0] } return &imageHelper{ fileName: fileName, scale: s, } } func (r *imageHelper) GuessFileFormat() (string, error) { if r.……

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package main import ( "fmt" "github.com/coreos/pkg/progressutil" "io" "os" "path/filepath" "time" ) func combineMultipleFiles(outPutFile string, files ...string) { abs, err := filepath.Abs(outPutFile) if err != nil { panic("can not get outPutFile absolute path") } dir := filepath.Dir(abs) if _, err := os.Stat(dir); err != nil { if os.IsNotExist(err) { err := os.MkdirAll(dir, os.ModePerm) if err != nil { panic(fmt.Sprintf("can not mkdirs, path: %s, err: %s", dir, err)) } } } file, err := os.……

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package main import ( "encoding/json" "fmt" "github.com/go-playground/locales/en" "github.com/go-playground/locales/zh" "github.com/go-playground/locales/zh_Hant_TW" ut "github.com/go-playground/universal-translator" "github.com/go-playground/validator/v10" entranslations "github.com/go-playground/validator/v10/translations/en" zhtranslations "github.com/go-playground/validator/v10/translations/zh" zhtwtranslations "github.com/go-playground/validator/v10/translations/zh_tw" "reflect" "strings" ) type InternalAccountTransferRequest struct { Name string `json:"name" binding:"required"` Age string `json:"age_test" binding:"required"` Class string `binding:"required"` } func main() { s := `{"name": "123"}` var requset InternalAccountTransferRequest json.Unmarshal([]byte(s), &requset) //requset.Class = "123" v := validator.New() var err error uni := ut.New(en.New(), en.New(), zh_Hant_TW.New(), zh.New()) zh_, _ := uni.GetTranslator("zh") zhtranslations.RegisterDefaultTranslations(v, zh_) tw_, _ := uni.……

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