{"id":208298,"date":"2025-07-08T09:31:24","date_gmt":"2025-07-08T01:31:24","guid":{"rendered":"https:\/\/server.hk\/cnblog\/208298\/"},"modified":"2025-07-08T09:31:24","modified_gmt":"2025-07-08T01:31:24","slug":"%e6%89%93%e5%8d%b0%e5%90%8e%e5%8f%b0%e5%a4%84%e7%90%86%e7%a8%8b%e5%ba%8f%e6%a6%82%e5%bf%b5-api-%e5%92%8c%e9%80%9a%e9%81%93%ef%bc%9a%e5%b0%86%e4%bd%9c%e4%b8%9a%e4%bb%8eservehttp-%e4%bc%a0%e9%80%92","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/208298\/","title":{"rendered":"\u6253\u5370\u540e\u53f0\u5904\u7406\u7a0b\u5e8f\u6982\u5ff5\/API \u548c\u901a\u9053\uff1a\u5c06\u4f5c\u4e1a\u4eceserveHTTP \u4f20\u9012\u5230\u961f\u5217\u7684\u95ee\u9898"},"content":{"rendered":"

<\/b> <\/p>\n

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u6253\u5370\u540e\u53f0\u5904\u7406\u7a0b\u5e8f\u6982\u5ff5\/API \u548c\u901a\u9053\uff1a\u5c06\u4f5c\u4e1a\u4eceserveHTTP \u4f20\u9012\u5230\u961f\u5217\u7684\u95ee\u9898<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-05-01 14:09:38<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u54c8\u55bd\uff01\u4eca\u5929\u5fc3\u8840\u6765\u6f6e\u7ed9\u5927\u5bb6\u5e26\u6765\u4e86\u300a\u6253\u5370\u540e\u53f0\u5904\u7406\u7a0b\u5e8f\u6982\u5ff5\/API \u548c\u901a\u9053\uff1a\u5c06\u4f5c\u4e1a\u4eceserveHTTP \u4f20\u9012\u5230\u961f\u5217\u7684\u95ee\u9898\u300b<\/span>\uff0c\u60f3\u5fc5\u5927\u5bb6\u5e94\u8be5\u5bf9Golang<\/span>\u90fd\u4e0d\u964c\u751f\u5427\uff0c\u90a3\u4e48\u9605\u8bfb\u672c\u6587\u5c31\u90fd\u4e0d\u4f1a\u5f88\u56f0\u96be\uff0c\u4ee5\u4e0b\u5185\u5bb9\u4e3b\u8981\u6d89\u53ca\u5230<\/span>\uff0c\u82e5\u662f\u4f60\u6b63\u5728\u5b66\u4e60Golang<\/span>\uff0c\u5343\u4e07\u522b\u9519\u8fc7\u8fd9\u7bc7\u6587\u7ae0~\u5e0c\u671b\u80fd\u5e2e\u52a9\u5230\u4f60\uff01<\/p>\n

\u95ee\u9898\u5185\u5bb9
\n <\/p>\n

\u8fd9\u91cc\u5df2\u7ecf\u5f97\u5230\u4e86\u4e00\u4e9b\u5e2e\u52a9\uff0c\u8fd9\u8ba9\u6211\u5728\u6211\u6b63\u5728\u5c1d\u8bd5\u7684\u8fd9\u4e2a\u6982\u5ff5\u4e0a\u53d6\u5f97\u4e86\u8fdb\u5c55\uff0c\u4f46\u5b83\u4ecd\u7136\u4e0d\u592a\u6709\u6548\uff0c\u800c\u4e14\u6211\u9047\u5230\u4e86\u4e00\u4e2a\u6211\u4f3c\u4e4e\u65e0\u6cd5\u89e3\u51b3\u7684\u51b2\u7a81\u3002<\/p>\n

\u6211\u5728\u8fd9\u91cc\u5c1d\u8bd5\u5728\u6d41\u7a0b\u56fe\u4e2d\u8bf4\u660e\u6211\u60f3\u8981\u7684\u5185\u5bb9 – \u8bf7\u6ce8\u610f\uff0c\u5ba2\u6237\u7aef\u53ef\u4ee5\u662f\u8bb8\u591a\u5c06\u53d1\u9001\u6253\u5370\u4f5c\u4e1a\u7684\u5ba2\u6237\u7aef\uff0c\u56e0\u6b64\u6211\u4eec\u65e0\u6cd5\u56de\u590d\u5f53\u65f6\u6b63\u5728\u5904\u7406\u6211\u4eec\u4f5c\u4e1a\u7684\u5de5\u4f5c\u4eba\u5458\uff0c\u4f46\u5bf9\u4e8e\u5927\u591a\u6570\u4eba\u6765\u8bf4\u4f1a\u7684\uff08\u9ad8\u5cf0\u65f6\u6bb5\u4e0d\u4f1a\uff0c\u56e0\u4e3a\u6253\u5370\u5904\u7406\u5de5\u4f5c\u53ef\u80fd\u9700\u8981\u65f6\u95f4\uff09\u3002<\/p>\n

type queueelement struct {\n    jobid string\n    rw   http.responsewriter\n  donechan chan struct{}\n}\n\ntype globalvars struct {\n    db   *sql.db\n    wg   sync.waitgroup\n    jobs chan queueelement\n}\n\nfunc (gv *globalvars) servehttp(w http.responsewriter, r *http.request) {\n\n    switch r.url.path {\n    case \"\/startjob\":\n        fmt.printf (\"incoming\\r\\n\")\n\n            donec := make(chan struct{}, 1) \/\/buffered channel in order not to block the worker routine\n            newprintjob := queueelement{\n                    donechan: donec,    \n                    jobid:    \"jobid\",\n            }\n\n            gv.jobs <- newprintjob\n            func(donechan chan struct{},w http.responsewriter) {\n\n                  ctx, cancel := context.withtimeout(context.background(), 5*time.second)\n                    defer cancel()\n                    select {\n                    \/\/if this triggers first, then this waiting goroutine would exit\n                    \/\/and nobody would be listeding the 'donechan'. this is why it has to be buffered.\n                    case <-ctx.done():\n                            fmt.fprintf(w, \"job is taking more than 5 seconds to complete\\r\\n\")\n                            fmt.printf (\"took longer than 5 secs\\r\\n\")\n                    case <-donechan:\n                            fmt.fprintf(w, \"instant reply from servehttp\\r\\n\")\n                            fmt.printf (\"instant\\r\\n\")\n                    }\n            }(donec,w)\n\n    default:\n            fmt.fprintf(w, \"no such api\")\n    }\n}\n\nfunc worker(jobs <-chan queueelement) {\n    for {\n            job := <-jobs\n            processexec (\"start \/i \/b try.cmd\")\n            fmt.printf (\"job done\")\n        \/\/  processexec(\"start \/i \/b processandprint.exe -\" + job.jobid)\n            job.donechan <- struct{}{}\n\n    }\n}\n\nfunc main() {\n      db, err := sql.open(\"sqlite3\", \"jobs.sqlite\")\n      if err := db.ping(); err != nil {\n        log.fatal(err)\n    }   \n\n      db.setmaxopenconns(1) \/\/ prevents locked database error\n      _, err = db.exec(setupsql)\n      if err != nil {\n          log.fatal(err)\n      }\n\n    \/\/ create a globalvars instance\n    gv := globalvars{\n        db  :   db,\n        jobs: make(chan queueelement),\n    }\n    go worker (gv.jobs)\n    \/\/ create an http.server instance and specify our job manager as\n    \/\/ the handler for requests.\n    server := http.server{\n        handler: &gv,\n        addr : \":8888\",\n    }\n    \/\/ start server and accept connections.\n    log.fatal(server.listenandserve())\n}<\/pre>\n
\u4e0a\u9762\u7684\u4ee3\u7801\u662fservehttp\u548c\u5de5\u4f5c\u4eba\u5458\u5728\u6b64\u5904\u7684\u5e2e\u52a9\u4e0b\uff0c\u6700\u521dservehttp\u5185\u90e8\u7684func\u662f\u4e00\u4e2ago\u4f8b\u7a0b\uff0c\u5bf9\u6211\u6765\u8bf4\u6574\u4e2a\u51b2\u7a81\u5c31\u5728\u8fd9\u91cc\u51fa\u73b0 – \u8fd9\u4e2a\u6982\u5ff5\u662f\u5728servehttp\u4e2d\u5b83\u4ea7\u751f\u4e86\u4e00\u4e2a\u8fdb\u7a0b\u5982\u679c\u5de5\u4f5c\u4eba\u5458\u80fd\u591f\u5728 5 \u79d2\u5185\u53ca\u65f6\u5904\u7406\u4f5c\u4e1a\uff0c\u5c06\u4f1a\u6536\u5230\u5de5\u4f5c\u4eba\u5458\u7684\u56de\u590d\u3002<\/p>\n
\u5982\u679c\u5de5\u4f5c\u80fd\u591f\u57281\u79d2\u5185\u5b8c\u6210\uff0c\u6211\u60f3\u57281\u79d2\u540e\u7acb\u5373\u56de\u590d\u5ba2\u6237\u7aef\uff0c\u5982\u679c\u9700\u89813\u79d2\uff0c\u6211\u60f3\u57283\u79d2\u540e\u56de\u590d\uff0c\u5982\u679c\u9700\u8981\u8d85\u8fc75\u79d2\uff0c\u6211\u5c06\u53d1\u9001\u56de\u590d5\u79d2\u540e\uff08\u5982\u679c\u5de5\u4f5c\u9700\u898113\u79d2\u6211\u4ecd\u7136\u60f3\u57285\u79d2\u540e\u56de\u590d\uff09\u3002\u4ece\u73b0\u5728\u5f00\u59cb\uff0c\u5ba2\u6237\u5fc5\u987b\u5bf9\u5de5\u4f5c\u8fdb\u884c\u8f6e\u8be2 – \u4f46\u51b2\u7a81\u662f\uff1a<\/p>\n
a) \u5f53 servehttp \u9000\u51fa\u65f6 – \u7136\u540e responsewriter \u5173\u95ed – \u5e76\u4e14\u4e3a\u4e86\u80fd\u591f\u56de\u590d\u5ba2\u6237\u7aef\uff0c\u6211\u4eec\u5fc5\u987b\u5c06\u7b54\u6848\u5199\u5165 responsewriter\u3002<\/p>\n
b) \u5982\u679c\u6211\u963b\u6b62\u4e86servehttp\uff08\u5c31\u50cf\u4e0b\u9762\u7684\u4ee3\u7801\u793a\u4f8b\u4e2d\uff0c\u6211\u4e0d\u5c06 func \u4f5c\u4e3a go \u4f8b\u7a0b\u8c03\u7528\uff09\uff0c\u90a3\u4e48\u5b83\u4e0d\u4ec5\u4f1a\u5f71\u54cd\u5355\u4e2a api \u8c03\u7528\uff0c\u800c\u4e14\u4f3c\u4e4e\u4e4b\u540e\u7684\u6240\u6709\u5176\u4ed6\u8c03\u7528\u90fd\u4f1a\u53d7\u5230\u5f71\u54cd\uff0c\u56e0\u6b64\uff0c\u7b2c\u4e00\u4e2a\u547c\u53eb\u5c06\u53ca\u65f6\u6b63\u786e\u5730\u5f97\u5230\u670d\u52a1\uff0c\u4f46\u5728\u7b2c\u4e00\u4e2a\u547c\u53eb\u4e4b\u540e\u540c\u65f6\u8fdb\u5165\u7684\u547c\u53eb\u5c06\u88ab\u963b\u585e\u64cd\u4f5c\u4f9d\u6b21\u5ef6\u8fdf\u3002<\/p>\n
c) \u5982\u679c\u6211\u4e0d\u963b\u6b62\u5b83 – \u5e76\u5c06\u5176\u66f4\u6539\u4e3a go \u4f8b\u7a0b\uff1a<\/p>\n
gv.jobs <- newPrintJob\n    go func(doneChan chan struct{},w http.ResponseWriter) {<\/pre>\n
\u7136\u540e\u6ca1\u6709\u5ef6\u8fdf – \u53ef\u4ee5\u8c03\u7528\u8bb8\u591a api – \u4f46\u95ee\u9898\u662f\uff0cservehttp \u7acb\u5373\u5b58\u5728\uff0c\u4ece\u800c\u6740\u6b7b responsewriter\uff0c\u7136\u540e\u6211\u65e0\u6cd5\u56de\u590d\u5ba2\u6237\u7aef\u3002<\/p>\n
\u6211\u4e0d\u786e\u5b9a\u5982\u4f55\u89e3\u51b3\u8fd9\u4e2a\u51b2\u7a81\uff0c\u5728\u4e0d\u5bfc\u81f4\u4efb\u4f55\u670d\u52a1\u963b\u585e\u7684\u60c5\u51b5\u4e0b\uff0c\u6211\u53ef\u4ee5\u5e76\u884c\u5904\u7406\u6240\u6709\u8bf7\u6c42\uff0c\u4f46\u4ecd\u7136\u80fd\u591f\u56de\u590d\u6709\u95ee\u9898\u7684 responsewriter\u3002<\/p>\n
\u6709\u4ec0\u4e48\u65b9\u6cd5\u53ef\u4ee5\u9632\u6b62servehttp\u5173\u95ed\u54cd\u5e94\u7f16\u5199\u5668\uff0c\u5373\u4f7f\u8be5\u51fd\u6570\u5b58\u5728\uff1f<\/p>\n
 <\/p>\n
\u89e3\u51b3\u65b9\u6848<\/h2>\n
 <\/p>\n
\u6211\u5df2\u5bf9\u60a8\u7684\u4ee3\u7801\u6dfb\u52a0\u4e86\u4e00\u4e9b\u66f4\u65b0\u3002\u73b0\u5728\u5b83\u7684\u5de5\u4f5c\u539f\u7406\u6b63\u5982\u60a8\u6240\u63cf\u8ff0\u7684\u90a3\u6837\u3002<\/p>\n
package main\n\nimport (\n    \"database\/sql\"\n    \"fmt\"\n    \"log\"\n    \"math\/rand\"\n    \"net\/http\"\n    \"sync\"\n    \"time\"\n)\n\ntype QueueElement struct {\n    jobid    string\n    rw       http.ResponseWriter\n    doneChan chan struct{}\n}\n\ntype GlobalVars struct {\n    db   *sql.DB\n    wg   sync.WaitGroup\n    jobs chan QueueElement\n}\n\nfunc (gv *GlobalVars) ServeHTTP(w http.ResponseWriter, r *http.Request) {\n\n    switch r.URL.Path {\n    case \"\/StartJob\":\n        fmt.Printf(\"incoming\\r\\n\")\n\n        doneC := make(chan struct{}, 1) \/\/Buffered channel in order not to block the worker routine\n\n        go func(doneChan chan struct{}, w http.ResponseWriter) {\n            gv.jobs <- QueueElement{\n                doneChan: doneC,\n                jobid:    \"jobid\",\n            }\n        }(doneC, w)\n\n        select {\n        case <-time.Tick(time.Second * 5):\n            fmt.Fprintf(w, \"job is taking more than 5 seconds to complete\\r\\n\")\n            fmt.Printf(\"took longer than 5 secs\\r\\n\")\n        case <-doneC:\n            fmt.Fprintf(w, \"instant reply from serveHTTP\\r\\n\")\n            fmt.Printf(\"instant\\r\\n\")\n        }\n    default:\n        fmt.Fprintf(w, \"No such Api\")\n    }\n}\n\nfunc worker(jobs <-chan QueueElement) {\n    for {\n        job := <-jobs\n        fmt.Println(\"START \/i \/b try.cmd\")\n        fmt.Printf(\"job done\")\n\n        randTimeDuration := time.Second * time.Duration(rand.Intn(7))\n\n        time.Sleep(randTimeDuration)\n\n        \/\/  processExec(\"START \/i \/b processAndPrint.exe -\" + job.jobid)\n        job.doneChan <- struct{}{}\n    }\n}\n\nfunc main() {\n\n    \/\/ create a GlobalVars instance\n    gv := GlobalVars{\n        \/\/db:   db,\n        jobs: make(chan QueueElement),\n    }\n    go worker(gv.jobs)\n    \/\/ create an http.Server instance and specify our job manager as\n    \/\/ the handler for requests.\n    server := http.Server{\n        Handler: &gv,\n        Addr:    \":8888\",\n    }\n    \/\/ start server and accept connections.\n    log.Fatal(server.ListenAndServe())\n}\n<\/pre>\n
\u662f\u7684\uff0c\u4f60\u7684\u89c2\u70b9\u662f\u5bf9\u7684\u201cc\uff09\u5982\u679c\u6211\u4e0d\u963b\u6b62\u5b83\u201d<\/strong>\u3002<\/p>\n
\u4e3a\u4e86\u4fdd\u5b58\u54cd\u5e94\u7f16\u5199\u5668\uff0c\u60a8\u4e0d\u5e94\u8be5\u5728\u5176\u4e2d\u8c03\u7528 go \u4f8b\u7a0b\u3002\u76f8\u53cd\uff0c\u60a8\u5e94\u8be5\u5c06 servehttp<\/strong> \u8c03\u7528\u4e3a go-routine\uff0c\u5927\u591a\u6570 http \u670d\u52a1\u5668\u5b9e\u73b0\u90fd\u662f\u8fd9\u6837\u505a\u7684\u3002 
 \u8fd9\u6837\u60a8\u5c31\u4e0d\u4f1a\u963b\u6b62\u4efb\u4f55 api \u8c03\u7528\uff0c\u6bcf\u4e2a api \u8c03\u7528\u5c06\u5728\u4e0d\u540c\u7684 go \u4f8b\u7a0b\u4e2d\u8fd0\u884c\uff0c\u5e76\u88ab\u5176\u529f\u80fd\u963b\u6b62\u3002<\/p>\n
\u7531\u4e8e\u60a8\u7684\u201cjobs chan queueelement\u201d<\/strong>\u662f\u5355\u4e2a\u901a\u9053\uff08\u4e0d\u662f\u7f13\u51b2\u901a\u9053\uff09\uff0c\u56e0\u6b64\u60a8\u7684\u6240\u6709\u8fdb\u7a0b\u90fd\u4f1a\u5728\u201cgv.jobs <- newprintjob\u201d<\/strong>\u5904\u88ab\u963b\u6b62.
 \u60a8\u5e94\u8be5\u4f7f\u7528\u7f13\u51b2\u901a\u9053\uff0c\u4ee5\u4fbf\u6240\u6709 api \u8c03\u7528\u90fd\u53ef\u4ee5\u5c06\u5176\u6dfb\u52a0\u5230\u961f\u5217\u4e2d\uff0c\u5e76\u6839\u636e\u5de5\u4f5c\u5b8c\u6210\u6216\u8d85\u65f6\u83b7\u5f97\u54cd\u5e94\u3002 <\/p>\n
 \u62e5\u6709\u7f13\u51b2\u901a\u9053\u4e5f\u53ef\u4ee5\u6a21\u62df\u6253\u5370\u673a\u7684\u73b0\u5b9e\u5185\u5b58\u9650\u5236\u3002 \uff08\u961f\u5217\u957f\u5ea61\u4e3a\u7279\u4f8b\uff09<\/p>\n
\u4ee5\u4e0a\u5c31\u662f\u300a\u6253\u5370\u540e\u53f0\u5904\u7406\u7a0b\u5e8f\u6982\u5ff5\/API \u548c\u901a\u9053\uff1a\u5c06\u4f5c\u4e1a\u4eceserveHTTP \u4f20\u9012\u5230\u961f\u5217\u7684\u95ee\u9898\u300b\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u5173\u4e8e\u7684\u8d44\u6599\u8bf7\u5173\u6ce8\u516c\u4f17\u53f7\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5f53\u524d\u4f4d\u7f6e\uff1a > > ...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-208298","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208298","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=208298"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208298\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=208298"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=208298"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=208298"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}