const{createApp}=Vue
const{createVuetify,useGoTo,useDisplay}=Vuetify
var data={alert:{show:false,color:'success',text:'',timeout:0,},theme:{dark:false,},nav:{showDrawer:false,showTOC:true,tocPanel:0,tab:'account',post:{discussionId:6627,currentPage:1,targetPage:1,total:3,anchor:0,goToOptions:{container:null,duration:0,easing:'easeInOutCubic',offset:-100,},worker:null,task:[],active:[],apiLock:[],originLike:new Map([]),},related:{block:1,}},search:{width:80,text:null,loading:false,},tags:[{id:27,url:'/t/0e2e58346a045c7567770b2b3120',name:'Go',color:'#FFA726',icon:'mdi-language-go',},],posts:[{id:81482,num:0,uid:8008,content:'\u003Cp\u003E晚上看了会 Medium 上的博客，发现了一篇关于使用 Go 来实现并发的获取数据。\u003C/p\u003E\u003Cp\u003E我在作者原有的基础上改造了一下，限制了最大的数量，不知道有没有什么疏漏，请大家指教指教。\u003C/p\u003E\u003Cp\u003E另外我也在思考关于 GC 的问题，如果代码中在某一次循环中走了\u0026lt;-ctx.Done()的分支，直接返回了结果，productsChan 会被怎么回收？我应该如何关闭相关的 channel ？还是让程序自己处理？\u003C/p\u003E\u003Cp\u003EMedium 原文地址\u003C/p\u003E\u003Cp\u003E我的改造：\u003C/p\u003E\u003Ccode\u003Epackage mainimport \u0026#34;sync\u0026#34;import \u0026#34;runtime\u0026#34;import \u0026#34;fmt\u0026#34;var LIST_PRODUCT_TYPE \u003D [100000]string{\u0026#34;food\u0026#34;, \u0026#34;electronics\u0026#34;, \u0026#34;clothing\u0026#34;,\u0026#34;...more\u0026#34;} // ......非常多的数据需要查询type GetListProductResponse struct {    Data []ProductListResponse `json:\u0026#34;data\u0026#34;`}type ProductListResponse struct {    Code         string `json:\u0026#34;code\u0026#34;`    Name         string `json:\u0026#34;name\u0026#34;`    Price        string `json:\u0026#34;price\u0026#34;`    Status       bool   `json:\u0026#34;status\u0026#34;`}func getProducts(ctx context.Context, req *GetProductListRequest) (*GetListProductResponse, error) {    // calling endpoint 3rd party    // parse to response    // and return the data    return \u0026amp;productList, nil}func main() {    ctx, cancelFunc :\u003D context.WithCancel(ctx)defer cancelFunc()    wg :\u003D sync.WaitGroup{}    doneChan :\u003D make(chan struct{}, 1)    productsChan :\u003D make(chan *GetListProductResponse)    errChan :\u003D make(chan error)    // LIST_PRODUCT_TYPE 数量非常大,需要限制最大的并发数量    maxConcurrency :\u003D 5    semaphore :\u003D make(chan struct{}, maxConcurrency)    wg.Add(len(LIST_PRODUCT_TYPE))    for key :\u003D range LIST_PRODUCT_TYPE {        req :\u003D \u0026amp;GetProductListRequest{            ProductType: LIST_PRODUCT_TYPE[key],        }        select {        case \u0026lt;-ctx.Done():            return nil, ctx.Err()        case semaphore\u0026lt;-struct{}{}:            go func() {                defer wg.Done()                defer func() { \u0026lt;-semaphore }()                products, err :\u003D getProductList(ctx, req)                if err !\u003D nil {                    errChan \u0026lt;- err                    return                }                productsChan \u0026lt;- products            }()        }     }     go func() {         wg.Wait()         doneChan \u0026lt;- struct{}{}     }()     var (         catalogues GetListProductResponse         data       []ProductListResponse     )      for {         select {         case \u0026lt;-ctx.Done():             return nil, ctx.Err()         case err :\u003D \u0026lt;-errChan:             return nil, err         case products :\u003D \u0026lt;-productsChan:             data \u003D append(data, products.Data...)             catalogues.Data \u003D data         case \u0026lt;-doneChan:         return \u0026amp;catalogues, nil     }   }}\u003C/code\u003E',ipRegion:'',updatedByUid:0,createdAt:'2025-03-26 22:59:08',updatedAt:'2025-03-28 10:45:44',mentionNum:0,mentionedBy:[],mentionUsers:[],likeUsers:[],},{id:81483,num:1,uid:811,content:'新手自己写容易出问题，推荐： https://github.com/sourcegraph/conc',ipRegion:'',updatedByUid:0,createdAt:'2025-03-26 23:16:48',updatedAt:'2025-03-28 10:45:44',mentionNum:0,mentionedBy:[],mentionUsers:[],likeUsers:[],},{id:81484,num:2,uid:8008,content:'感谢，我学习下这个库的实现',ipRegion:'',updatedByUid:0,createdAt:'2025-03-26 23:37:55',updatedAt:'2025-03-28 10:45:44',mentionNum:0,mentionedBy:[],mentionUsers:[],likeUsers:[],},],usersMap:new Map([[8008,{uid:8008,url:'/u/0f1c6a256a045c7f606a5e6f363c2003',avatar:'/a/0f1c6a256a045c7f606a5e6f363c2003',username:'supuwoerc🤖',}],[811,{uid:811,url:'/u/6327551d6a045c77686b576f230b0028',avatar:'/a/6327551d6a045c77686b576f230b0028',username:'dcalsky🤖',}],]),related:[{title:'大佬们平时都是怎样调试查看变量变化的？ go 有哪些方便实时展示变量的库或工具？',url:'/d/221f67216a045c77606a567a455c636a23050963',},{title:'Cursor Go 开发，有哪些必装的插件？',url:'/d/337a733f6a045c77606a56754f5b6b6a39061e13',},{title:'在 Go 项目里，涉及到金额计算，大家一般用什么方式？',url:'/d/30267d146a045c77606a5675425d606a3f732227',},{title:'[全职]广州 - 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const App={setup(){const goTo=useGoTo()
const{mdAndUp}=useDisplay()
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const app=createApp(App)
app.use(vuetify).mount("#app")