{"id":2029,"date":"2023-05-05T10:47:15","date_gmt":"2023-05-05T02:47:15","guid":{"rendered":"\/?p=2029"},"modified":"2023-05-05T10:47:15","modified_gmt":"2023-05-05T02:47:15","slug":"go%e5%ae%89%e5%85%a8%e6%8c%87%e5%8d%97","status":"publish","type":"post","link":"\/?p=2029","title":{"rendered":"Go\u5b89\u5168\u6307\u5357"},"content":{"rendered":"<h1>\u901a\u7528\u7c7b<\/h1>\n<p><a id=\"1.1\"><\/a><\/p>\n<h2>1. \u4ee3\u7801\u5b9e\u73b0\u7c7b<\/h2>\n<p><a id=\"1.1.1\"><\/a><\/p>\n<h3>1.1 \u5185\u5b58\u7ba1\u7406<\/h3>\n<h4>1.1.1\u3010\u5fc5\u987b\u3011\u5207\u7247\u957f\u5ea6\u6821\u9a8c<\/h4>\n<ul>\n<li>\u5728\u5bf9slice\u8fdb\u884c\u64cd\u4f5c\u65f6\uff0c\u5fc5\u987b\u5224\u65ad\u957f\u5ea6\u662f\u5426\u5408\u6cd5\uff0c\u9632\u6b62\u7a0b\u5e8fpanic<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad: \u672a\u5224\u65addata\u7684\u957f\u5ea6\uff0c\u53ef\u5bfc\u81f4 index out of range\nfunc decode(data []byte) bool {\n    if data[0] == &#039;F&#039; &amp;&amp; data[1] == &#039;U&#039; &amp;&amp; data[2] == &#039;Z&#039; &amp;&amp; data[3] == &#039;Z&#039; &amp;&amp; data[4] == &#039;E&#039; &amp;&amp; data[5] == &#039;R&#039; {\n        fmt.Println(&quot;Bad&quot;)\n        return true\n    }\n    return false\n}\n\n\/\/ bad: slice bounds out of range\nfunc foo() {\n    var slice = []int{0, 1, 2, 3, 4, 5, 6}\n    fmt.Println(slice[:10])\n}\n\n\/\/ good: \u4f7f\u7528data\u524d\u5e94\u5224\u65ad\u957f\u5ea6\u662f\u5426\u5408\u6cd5\nfunc decode(data []byte) bool {\n    if len(data) == 6 {\n        if data[0] == &#039;F&#039; &amp;&amp; data[1] == &#039;U&#039; &amp;&amp; data[2] == &#039;Z&#039; &amp;&amp; data[3] == &#039;Z&#039; &amp;&amp; data[4] == &#039;E&#039; &amp;&amp; data[5] == &#039;R&#039; {\n            fmt.Println(&quot;Good&quot;)\n            return true\n        }\n    }\n    return false\n}<\/code><\/pre>\n<h4>1.1.2\u3010\u5fc5\u987b\u3011nil\u6307\u9488\u5224\u65ad<\/h4>\n<ul>\n<li>\u8fdb\u884c\u6307\u9488\u64cd\u4f5c\u65f6\uff0c\u5fc5\u987b\u5224\u65ad\u8be5\u6307\u9488\u662f\u5426\u4e3anil\uff0c\u9632\u6b62\u7a0b\u5e8fpanic\uff0c\u5c24\u5176\u5728\u8fdb\u884c\u7ed3\u6784\u4f53Unmarshal\u65f6<\/li>\n<\/ul>\n<pre><code class=\"language-go\">type Packet struct {\n    PackeyType    uint8\n    PackeyVersion uint8\n    Data          *Data\n}\n\ntype Data struct {\n    Stat uint8\n    Len  uint8\n    Buf  [8]byte\n}\n\nfunc (p *Packet) UnmarshalBinary(b []byte) error {\n    if len(b) &lt; 2 {\n        return io.EOF\n    }\n\n    p.PackeyType = b[0]\n    p.PackeyVersion = b[1]\n\n    \/\/ \u82e5\u957f\u5ea6\u7b49\u4e8e2\uff0c\u90a3\u4e48\u4e0d\u4f1anew Data\n    if len(b) &gt; 2 {\n        p.Data = new(Data)\n    }\n    return nil\n}\n\n\/\/ bad: \u672a\u5224\u65ad\u6307\u9488\u662f\u5426\u4e3anil\nfunc main() {\n    packet := new(Packet)\n    data := make([]byte, 2)\n    if err := packet.UnmarshalBinary(data); err != nil {\n        fmt.Println(&quot;Failed to unmarshal packet&quot;)\n        return\n    }\n\n    fmt.Printf(&quot;Stat: %v\\n&quot;, packet.Data.Stat)\n}\n\n\/\/ good: \u5224\u65adData\u6307\u9488\u662f\u5426\u4e3anil\nfunc main() {\n    packet := new(Packet)\n    data := make([]byte, 2)\n\n    if err := packet.UnmarshalBinary(data); err != nil {\n        fmt.Println(&quot;Failed to unmarshal packet&quot;)\n        return\n    }\n\n    if packet.Data == nil {\n        return\n    }\n\n    fmt.Printf(&quot;Stat: %v\\n&quot;, packet.Data.Stat)\n}<\/code><\/pre>\n<h4>1.1.3\u3010\u5fc5\u987b\u3011\u6574\u6570\u5b89\u5168<\/h4>\n<ul>\n<li>\n<p>\u5728\u8fdb\u884c\u6570\u5b57\u8fd0\u7b97\u64cd\u4f5c\u65f6\uff0c\u9700\u8981\u505a\u597d\u957f\u5ea6\u9650\u5236\uff0c\u9632\u6b62\u5916\u90e8\u8f93\u5165\u8fd0\u7b97\u5bfc\u81f4\u5f02\u5e38\uff1a<\/p>\n<ul>\n<li>\u786e\u4fdd\u65e0\u7b26\u53f7\u6574\u6570\u8fd0\u7b97\u65f6\u4e0d\u4f1a\u53cd\u8f6c<\/li>\n<li>\u786e\u4fdd\u6709\u7b26\u53f7\u6574\u6570\u8fd0\u7b97\u65f6\u4e0d\u4f1a\u51fa\u73b0\u6ea2\u51fa<\/li>\n<li>\u786e\u4fdd\u6574\u578b\u8f6c\u6362\u65f6\u4e0d\u4f1a\u51fa\u73b0\u622a\u65ad\u9519\u8bef<\/li>\n<li>\u786e\u4fdd\u6574\u578b\u8f6c\u6362\u65f6\u4e0d\u4f1a\u51fa\u73b0\u7b26\u53f7\u9519\u8bef<\/li>\n<\/ul>\n<\/li>\n<li>\n<p>\u4ee5\u4e0b\u573a\u666f\u5fc5\u987b\u4e25\u683c\u8fdb\u884c\u957f\u5ea6\u9650\u5236\uff1a<\/p>\n<ul>\n<li>\u4f5c\u4e3a\u6570\u7ec4\u7d22\u5f15<\/li>\n<li>\u4f5c\u4e3a\u5bf9\u8c61\u7684\u957f\u5ea6\u6216\u8005\u5927\u5c0f<\/li>\n<li>\u4f5c\u4e3a\u6570\u7ec4\u7684\u8fb9\u754c\uff08\u5982\u4f5c\u4e3a\u5faa\u73af\u8ba1\u6570\u5668\uff09<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad: \u672a\u9650\u5236\u957f\u5ea6\uff0c\u5bfc\u81f4\u6574\u6570\u6ea2\u51fa\nfunc overflow(numControlByUser int32) {\n    var numInt int32 = 0\n    numInt = numControlByUser + 1\n    \/\/ \u5bf9\u957f\u5ea6\u9650\u5236\u4e0d\u5f53\uff0c\u5bfc\u81f4\u6574\u6570\u6ea2\u51fa\n    fmt.Printf(&quot;%d\\n&quot;, numInt)\n    \/\/ \u4f7f\u7528numInt\uff0c\u53ef\u80fd\u5bfc\u81f4\u5176\u4ed6\u9519\u8bef\n}\n\nfunc main() {\n    overflow(2147483647)\n}\n\n\/\/ good\nfunc overflow(numControlByUser int32) {\n    var numInt int32 = 0\n    numInt = numControlByUser + 1\n    if numInt &lt; 0 {\n        fmt.Println(&quot;integer overflow&quot;)\n        return\n    }\n    fmt.Println(&quot;integer ok&quot;)\n}\n\nfunc main() {\n    overflow(2147483647)\n}<\/code><\/pre>\n<h4>1.1.4\u3010\u5fc5\u987b\u3011make\u5206\u914d\u957f\u5ea6\u9a8c\u8bc1<\/h4>\n<ul>\n<li>\u5728\u8fdb\u884cmake\u5206\u914d\u5185\u5b58\u65f6\uff0c\u9700\u8981\u5bf9\u5916\u90e8\u53ef\u63a7\u7684\u957f\u5ea6\u8fdb\u884c\u6821\u9a8c\uff0c\u9632\u6b62\u7a0b\u5e8fpanic\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc parse(lenControlByUser int, data []byte) {\n    size := lenControlByUser\n    \/\/ \u5bf9\u5916\u90e8\u4f20\u5165\u7684size\uff0c\u8fdb\u884c\u957f\u5ea6\u5224\u65ad\u4ee5\u514d\u5bfc\u81f4panic\n    buffer := make([]byte, size)\n    copy(buffer, data)\n}\n\n\/\/ good\nfunc parse(lenControlByUser int, data []byte) ([]byte, error) {\n    size := lenControlByUser\n    \/\/ \u9650\u5236\u5916\u90e8\u53ef\u63a7\u7684\u957f\u5ea6\u5927\u5c0f\u8303\u56f4\n    if size &gt; 64*1024*1024 {\n        return nil, errors.New(&quot;value too large&quot;)\n    }\n    buffer := make([]byte, size)\n    copy(buffer, data)\n    return buffer, nil\n}<\/code><\/pre>\n<h4>1.1.5\u3010\u5fc5\u987b\u3011\u7981\u6b62SetFinalizer\u548c\u6307\u9488\u5faa\u73af\u5f15\u7528\u540c\u65f6\u4f7f\u7528<\/h4>\n<ul>\n<li>\u5f53\u4e00\u4e2a\u5bf9\u8c61\u4ece\u88abGC\u9009\u4e2d\u5230\u79fb\u9664\u5185\u5b58\u4e4b\u524d\uff0cruntime.SetFinalizer()\u90fd\u4e0d\u4f1a\u6267\u884c\uff0c\u5373\u4f7f\u7a0b\u5e8f\u6b63\u5e38\u7ed3\u675f\u6216\u8005\u53d1\u751f\u9519\u8bef\u3002\u7531\u6307\u9488\u6784\u6210\u7684\u201c\u5faa\u73af\u5f15\u7528\u201d\u867d\u7136\u80fd\u88abGC\u6b63\u786e\u5904\u7406\uff0c\u4f46\u7531\u4e8e\u65e0\u6cd5\u786e\u5b9aFinalizer\u4f9d\u8d56\u987a\u5e8f\uff0c\u4ece\u800c\u65e0\u6cd5\u8c03\u7528runtime.SetFinalizer()\uff0c\u5bfc\u81f4\u76ee\u6807\u5bf9\u8c61\u65e0\u6cd5\u53d8\u6210\u53ef\u8fbe\u72b6\u6001\uff0c\u4ece\u800c\u9020\u6210\u5185\u5b58\u65e0\u6cd5\u88ab\u56de\u6536\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc foo() {\n    var a, b Data\n    a.o = &amp;b\n    b.o = &amp;a\n\n    \/\/ \u6307\u9488\u5faa\u73af\u5f15\u7528\uff0cSetFinalizer()\u65e0\u6cd5\u6b63\u5e38\u8c03\u7528\n    runtime.SetFinalizer(&amp;a, func(d *Data) {\n        fmt.Printf(&quot;a %p final.\\n&quot;, d)\n    })\n    runtime.SetFinalizer(&amp;b, func(d *Data) {\n        fmt.Printf(&quot;b %p final.\\n&quot;, d)\n    })\n}\n\nfunc main() {\n    for {\n        foo()\n        time.Sleep(time.Millisecond)\n    }\n}\n<\/code><\/pre>\n<h4>1.1.6\u3010\u5fc5\u987b\u3011\u7981\u6b62\u91cd\u590d\u91ca\u653echannel<\/h4>\n<ul>\n<li>\u91cd\u590d\u91ca\u653e\u4e00\u822c\u5b58\u5728\u4e8e\u5f02\u5e38\u6d41\u7a0b\u5224\u65ad\u4e2d\uff0c\u5982\u679c\u6076\u610f\u653b\u51fb\u8005\u6784\u9020\u51fa\u5f02\u5e38\u6761\u4ef6\u4f7f\u7a0b\u5e8f\u91cd\u590d\u91ca\u653echannel\uff0c\u5219\u4f1a\u89e6\u53d1\u8fd0\u884c\u65f6panic\uff0c\u4ece\u800c\u9020\u6210DoS\u653b\u51fb\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc foo(c chan int) {\n    defer close(c)\n    err := processBusiness()\n    if err != nil {\n        c &lt;- 0\n        close(c) \/\/ \u91cd\u590d\u91ca\u653echannel\n        return\n    }\n    c &lt;- 1\n}\n\n\/\/ good\nfunc foo(c chan int) {\n    defer close(c) \/\/ \u4f7f\u7528defer\u5ef6\u8fdf\u5173\u95edchannel\n    err := processBusiness()\n    if err != nil {\n        c &lt;- 0\n        return\n    }\n    c &lt;- 1\n}<\/code><\/pre>\n<h4>1.1.7\u3010\u5fc5\u987b\u3011\u786e\u4fdd\u6bcf\u4e2a\u534f\u7a0b\u90fd\u80fd\u9000\u51fa<\/h4>\n<ul>\n<li>\u542f\u52a8\u4e00\u4e2a\u534f\u7a0b\u5c31\u4f1a\u505a\u4e00\u4e2a\u5165\u6808\u64cd\u4f5c\uff0c\u5728\u7cfb\u7edf\u4e0d\u9000\u51fa\u7684\u60c5\u51b5\u4e0b\uff0c\u534f\u7a0b\u4e5f\u6ca1\u6709\u8bbe\u7f6e\u9000\u51fa\u6761\u4ef6\uff0c\u5219\u76f8\u5f53\u4e8e\u534f\u7a0b\u5931\u53bb\u4e86\u63a7\u5236\uff0c\u5b83\u5360\u7528\u7684\u8d44\u6e90\u65e0\u6cd5\u56de\u6536\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u5185\u5b58\u6cc4\u9732\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad: \u534f\u7a0b\u6ca1\u6709\u8bbe\u7f6e\u9000\u51fa\u6761\u4ef6\nfunc doWaiter(name string, second int) {\n    for {\n        time.Sleep(time.Duration(second) * time.Second)\n        fmt.Println(name, &quot; is ready!&quot;)\n    }\n}<\/code><\/pre>\n<h4>1.1.8\u3010\u63a8\u8350\u3011\u4e0d\u4f7f\u7528unsafe\u5305<\/h4>\n<ul>\n<li>\u7531\u4e8eunsafe\u5305\u7ed5\u8fc7\u4e86 Golang \u7684\u5185\u5b58\u5b89\u5168\u539f\u5219\uff0c\u4e00\u822c\u6765\u8bf4\u4f7f\u7528\u8be5\u5e93\u662f\u4e0d\u5b89\u5168\u7684\uff0c\u53ef\u5bfc\u81f4\u5185\u5b58\u7834\u574f\uff0c\u5c3d\u91cf\u907f\u514d\u4f7f\u7528\u8be5\u5305\u3002\u82e5\u5fc5\u987b\u8981\u4f7f\u7528unsafe\u64cd\u4f5c\u6307\u9488\uff0c\u5fc5\u987b\u505a\u597d\u5b89\u5168\u6821\u9a8c\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad: \u901a\u8fc7unsafe\u64cd\u4f5c\u539f\u59cb\u6307\u9488\nfunc unsafePointer() {\n    b := make([]byte, 1)\n    foo := (*int)(unsafe.Pointer(uintptr(unsafe.Pointer(&amp;b[0])) + uintptr(0xfffffffe)))\n    fmt.Print(*foo + 1)\n}\n\n\/\/ [signal SIGSEGV: segmentation violation code=0x1 addr=0xc100068f55 pc=0x49142b]\n<\/code><\/pre>\n<h4>1.1.9\u3010\u63a8\u8350\u3011\u4e0d\u4f7f\u7528slice\u4f5c\u4e3a\u51fd\u6570\u5165\u53c2<\/h4>\n<ul>\n<li>slice\u5728\u4f5c\u4e3a\u51fd\u6570\u5165\u53c2\u65f6\uff0c\u51fd\u6570\u5185\u5bf9slice\u7684\u4fee\u6539\u53ef\u80fd\u4f1a\u5f71\u54cd\u539f\u59cb\u6570\u636e<\/li>\n<\/ul>\n<pre><code class=\"language-go\">  \/\/ bad\n  \/\/ slice\u4f5c\u4e3a\u51fd\u6570\u5165\u53c2\u65f6\u5305\u542b\u539f\u59cb\u6570\u7ec4\u6307\u9488\n  func modify(array []int) {\n      array[0] = 10 \/\/ \u5bf9\u5165\u53c2slice\u7684\u5143\u7d20\u4fee\u6539\u4f1a\u5f71\u54cd\u539f\u59cb\u6570\u636e\n  }\n\n  func main() {\n      array := []int{1, 2, 3, 4, 5}\n\n      modify(array)\n      fmt.Println(array) \/\/ output\uff1a[10 2 3 4 5]\n  }\n\n  \/\/ good\n  \/\/ \u6570\u7ec4\u4f5c\u4e3a\u51fd\u6570\u5165\u53c2\uff0c\u800c\u4e0d\u662fslice\n  func modify(array [5]int) {\n    array[0] = 10\n  }\n\n  func main() {\n      \/\/ \u4f20\u5165\u6570\u7ec4\uff0c\u6ce8\u610f\u6570\u7ec4\u4e0eslice\u7684\u533a\u522b\n      array := [5]int{1, 2, 3, 4, 5}\n\n      modify(array)\n      fmt.Println(array)\n  }\n<\/code><\/pre>\n<p><a id=\"1.1.2\"><\/a><\/p>\n<h3>1.2 \u6587\u4ef6\u64cd\u4f5c<\/h3>\n<h4>1.2.1\u3010\u5fc5\u987b\u3011 \u8def\u5f84\u7a7f\u8d8a\u68c0\u67e5<\/h4>\n<ul>\n<li>\u5728\u8fdb\u884c\u6587\u4ef6\u64cd\u4f5c\u65f6\uff0c\u5982\u679c\u5bf9\u5916\u90e8\u4f20\u5165\u7684\u6587\u4ef6\u540d\u672a\u505a\u9650\u5236\uff0c\u53ef\u80fd\u5bfc\u81f4\u4efb\u610f\u6587\u4ef6\u8bfb\u53d6\u6216\u8005\u4efb\u610f\u6587\u4ef6\u5199\u5165\uff0c\u4e25\u91cd\u53ef\u80fd\u5bfc\u81f4\u4ee3\u7801\u6267\u884c\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad: \u4efb\u610f\u6587\u4ef6\u8bfb\u53d6\nfunc handler(w http.ResponseWriter, r *http.Request) {\n    path := r.URL.Query()[&quot;path&quot;][0]\n\n    \/\/ \u672a\u8fc7\u6ee4\u6587\u4ef6\u8def\u5f84\uff0c\u53ef\u80fd\u5bfc\u81f4\u4efb\u610f\u6587\u4ef6\u8bfb\u53d6\n    data, _ := ioutil.ReadFile(path)\n    w.Write(data)\n\n    \/\/ \u5bf9\u5916\u90e8\u4f20\u5165\u7684\u6587\u4ef6\u540d\u53d8\u91cf\uff0c\u8fd8\u9700\u8981\u9a8c\u8bc1\u662f\u5426\u5b58\u5728..\/\u7b49\u8def\u5f84\u7a7f\u8d8a\u7684\u6587\u4ef6\u540d\n    data, _ = ioutil.ReadFile(filepath.Join(&quot;\/home\/user\/&quot;, path))\n    w.Write(data)\n}\n\n\/\/ bad: \u4efb\u610f\u6587\u4ef6\u5199\u5165\nfunc unzip(f string) {\n    r, _ := zip.OpenReader(f)\n    for _, f := range r.File {\n        p, _ := filepath.Abs(f.Name)\n        \/\/ \u672a\u9a8c\u8bc1\u538b\u7f29\u6587\u4ef6\u540d\uff0c\u53ef\u80fd\u5bfc\u81f4..\/\u7b49\u8def\u5f84\u7a7f\u8d8a\uff0c\u4efb\u610f\u6587\u4ef6\u8def\u5f84\u5199\u5165\n        ioutil.WriteFile(p, []byte(&quot;present&quot;), 0640)\n    }\n}\n\n\/\/ good: \u68c0\u67e5\u538b\u7f29\u7684\u6587\u4ef6\u540d\u662f\u5426\u5305\u542b..\u8def\u5f84\u7a7f\u8d8a\u7279\u5f81\u5b57\u7b26\uff0c\u9632\u6b62\u4efb\u610f\u5199\u5165\nfunc unzipGood(f string) bool {\n    r, err := zip.OpenReader(f)\n    if err != nil {\n        fmt.Println(&quot;read zip file fail&quot;)\n        return false\n    }\n    for _, f := range r.File {\n        if !strings.Contains(f.Name, &quot;..&quot;) {\n            p, _ := filepath.Abs(f.Name)\n            ioutil.WriteFile(p, []byte(&quot;present&quot;), 0640)\n        } else {\n            return false\n        }\n    }\n    return true\n}<\/code><\/pre>\n<h4>1.2.2\u3010\u5fc5\u987b\u3011 \u6587\u4ef6\u8bbf\u95ee\u6743\u9650<\/h4>\n<ul>\n<li>\u6839\u636e\u521b\u5efa\u6587\u4ef6\u7684\u654f\u611f\u6027\u8bbe\u7f6e\u4e0d\u540c\u7ea7\u522b\u7684\u8bbf\u95ee\u6743\u9650\uff0c\u4ee5\u9632\u6b62\u654f\u611f\u6570\u636e\u88ab\u4efb\u610f\u6743\u9650\u7528\u6237\u8bfb\u53d6\u3002\u4f8b\u5982\uff0c\u8bbe\u7f6e\u6587\u4ef6\u6743\u9650\u4e3a\uff1a<code>-rw-r-----<\/code><\/li>\n<\/ul>\n<pre><code class=\"language-go\">ioutil.WriteFile(p, []byte(&quot;present&quot;), 0640)<\/code><\/pre>\n<p><a id=\"1.1.3\"><\/a><\/p>\n<h3>1.3 \u7cfb\u7edf\u63a5\u53e3<\/h3>\n<p><strong>1.3.1\u3010\u5fc5\u987b\u3011\u547d\u4ee4\u6267\u884c\u68c0\u67e5<\/strong><\/p>\n<ul>\n<li>\u4f7f\u7528<code>exec.Command<\/code>\u3001<code>exec.CommandContext<\/code>\u3001<code>syscall.StartProcess<\/code>\u3001<code>os.StartProcess<\/code>\u7b49\u51fd\u6570\u65f6\uff0c\u7b2c\u4e00\u4e2a\u53c2\u6570\uff08path\uff09\u76f4\u63a5\u53d6\u5916\u90e8\u8f93\u5165\u503c\u65f6\uff0c\u5e94\u4f7f\u7528\u767d\u540d\u5355\u9650\u5b9a\u53ef\u6267\u884c\u7684\u547d\u4ee4\u8303\u56f4\uff0c\u4e0d\u5141\u8bb8\u4f20\u5165<code>bash<\/code>\u3001<code>cmd<\/code>\u3001<code>sh<\/code>\u7b49\u547d\u4ee4\uff1b<\/li>\n<li>\u4f7f\u7528<code>exec.Command<\/code>\u3001<code>exec.CommandContext<\/code>\u7b49\u51fd\u6570\u65f6\uff0c\u901a\u8fc7<code>bash<\/code>\u3001<code>cmd<\/code>\u3001<code>sh<\/code>\u7b49\u521b\u5efashell\uff0c-c\u540e\u7684\u53c2\u6570\uff08arg\uff09\u62fc\u63a5\u5916\u90e8\u8f93\u5165\uff0c\u5e94\u8fc7\u6ee4\\n  $  &amp;  ;  |  '  &quot;  ( )  `\u7b49\u6f5c\u5728\u6076\u610f\u5b57\u7b26\uff1b<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc foo() {\n    userInputedVal := &quot;&amp;&amp; echo &#039;hello&#039;&quot; \/\/ \u5047\u8bbe\u5916\u90e8\u4f20\u5165\u8be5\u53d8\u91cf\u503c\n    cmdName := &quot;ping &quot; + userInputedVal\n\n    \/\/ \u672a\u5224\u65ad\u5916\u90e8\u8f93\u5165\u662f\u5426\u5b58\u5728\u547d\u4ee4\u6ce8\u5165\u5b57\u7b26\uff0c\u7ed3\u5408sh\u53ef\u9020\u6210\u547d\u4ee4\u6ce8\u5165\n    cmd := exec.Command(&quot;sh&quot;, &quot;-c&quot;, cmdName)\n    output, _ := cmd.CombinedOutput()\n    fmt.Println(string(output))\n\n    cmdName := &quot;ls&quot;\n    \/\/ \u672a\u5224\u65ad\u5916\u90e8\u8f93\u5165\u662f\u5426\u662f\u9884\u671f\u547d\u4ee4\n    cmd := exec.Command(cmdName)\n    output, _ := cmd.CombinedOutput()\n    fmt.Println(string(output))\n}\n\n\/\/ good\nfunc checkIllegal(cmdName string) bool {\n    if strings.Contains(cmdName, &quot;&amp;&quot;) || strings.Contains(cmdName, &quot;|&quot;) || strings.Contains(cmdName, &quot;;&quot;) ||\n        strings.Contains(cmdName, &quot;$&quot;) || strings.Contains(cmdName, &quot;&#039;&quot;) || strings.Contains(cmdName, &quot;`&quot;) ||\n        strings.Contains(cmdName, &quot;(&quot;) || strings.Contains(cmdName, &quot;)&quot;) || strings.Contains(cmdName, &quot;\\&quot;&quot;) {\n        return true\n    }\n    return false\n}\n\nfunc main() {\n    userInputedVal := &quot;&amp;&amp; echo &#039;hello&#039;&quot;\n    cmdName := &quot;ping &quot; + userInputedVal\n\n    if checkIllegal(cmdName) { \/\/ \u68c0\u67e5\u4f20\u7ed9sh\u7684\u547d\u4ee4\u662f\u5426\u6709\u7279\u6b8a\u5b57\u7b26\n        return \/\/ \u5b58\u5728\u7279\u6b8a\u5b57\u7b26\u76f4\u63a5return\n    }\n\n    cmd := exec.Command(&quot;sh&quot;, &quot;-c&quot;, cmdName)\n    output, _ := cmd.CombinedOutput()\n    fmt.Println(string(output))\n}<\/code><\/pre>\n<p><a id=\"1.1.4\"><\/a><\/p>\n<h3>1.4 \u901a\u4fe1\u5b89\u5168<\/h3>\n<h4>1.4.1\u3010\u5fc5\u987b\u3011\u7f51\u7edc\u901a\u4fe1\u91c7\u7528TLS\u65b9\u5f0f<\/h4>\n<ul>\n<li>\u660e\u6587\u4f20\u8f93\u7684\u901a\u4fe1\u534f\u8bae\u76ee\u524d\u5df2\u88ab\u9a8c\u8bc1\u5b58\u5728\u8f83\u5927\u5b89\u5168\u98ce\u9669\uff0c\u88ab\u4e2d\u95f4\u4eba\u52ab\u6301\u540e\u53ef\u80fd\u5bfc\u81f4\u8bb8\u591a\u5b89\u5168\u98ce\u9669\uff0c\u56e0\u6b64\u5fc5\u987b\u91c7\u7528\u81f3\u5c11TLS\u7684\u5b89\u5168\u901a\u4fe1\u65b9\u5f0f\u4fdd\u8bc1\u901a\u4fe1\u5b89\u5168\uff0c\u4f8b\u5982gRPC\/Websocket\u90fd\u4f7f\u7528TLS1.3\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ good\nfunc main() {\n    http.HandleFunc(&quot;\/&quot;, func(w http.ResponseWriter, req *http.Request) {\n        w.Header().Add(&quot;Strict-Transport-Security&quot;, &quot;max-age=63072000; includeSubDomains&quot;)\n        w.Write([]byte(&quot;This is an example server.\\n&quot;))\n    })\n\n    \/\/ \u670d\u52a1\u5668\u914d\u7f6e\u8bc1\u4e66\u4e0e\u79c1\u94a5\n    log.Fatal(http.ListenAndServeTLS(&quot;:443&quot;, &quot;yourCert.pem&quot;, &quot;yourKey.pem&quot;, nil))\n}<\/code><\/pre>\n<h4>1.4.2\u3010\u63a8\u8350\u3011TLS\u542f\u7528\u8bc1\u4e66\u9a8c\u8bc1<\/h4>\n<ul>\n<li>TLS\u8bc1\u4e66\u5e94\u5f53\u662f\u6709\u6548\u7684\u3001\u672a\u8fc7\u671f\u7684\uff0c\u4e14\u914d\u7f6e\u6b63\u786e\u7684\u57df\u540d\uff0c\u751f\u4ea7\u73af\u5883\u7684\u670d\u52a1\u7aef\u5e94\u542f\u7528\u8bc1\u4e66\u9a8c\u8bc1\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nimport (\n    &quot;crypto\/tls&quot;\n    &quot;net\/http&quot;\n)\n\nfunc doAuthReq(authReq *http.Request) *http.Response {\n    tr := &amp;http.Transport{\n        TLSClientConfig: &amp;tls.Config{InsecureSkipVerify: true},\n    }\n    client := &amp;http.Client{Transport: tr}\n    res, _ := client.Do(authReq)\n    return res\n}\n\n\/\/ good\nimport (\n    &quot;crypto\/tls&quot;\n    &quot;net\/http&quot;\n)\n\nfunc doAuthReq(authReq *http.Request) *http.Response {\n    tr := &amp;http.Transport{\n        TLSClientConfig: &amp;tls.Config{InsecureSkipVerify: false},\n    }\n    client := &amp;http.Client{Transport: tr}\n    res, _ := client.Do(authReq)\n    return res\n}<\/code><\/pre>\n<p><a id=\"1.1.5\"><\/a><\/p>\n<h3>1.5 \u654f\u611f\u6570\u636e\u4fdd\u62a4<\/h3>\n<h4>1.5.1\u3010\u5fc5\u987b\u3011\u654f\u611f\u4fe1\u606f\u8bbf\u95ee<\/h4>\n<ul>\n<li>\u7981\u6b62\u5c06\u654f\u611f\u4fe1\u606f\u786c\u7f16\u7801\u5728\u7a0b\u5e8f\u4e2d\uff0c\u65e2\u53ef\u80fd\u4f1a\u5c06\u654f\u611f\u4fe1\u606f\u66b4\u9732\u7ed9\u653b\u51fb\u8005\uff0c\u4e5f\u4f1a\u589e\u52a0\u4ee3\u7801\u7ba1\u7406\u548c\u7ef4\u62a4\u7684\u96be\u5ea6<\/li>\n<li>\u4f7f\u7528\u914d\u7f6e\u4e2d\u5fc3\u7cfb\u7edf\u7edf\u4e00\u6258\u7ba1\u5bc6\u94a5\u7b49\u654f\u611f\u4fe1\u606f<\/li>\n<\/ul>\n<h4>1.5.2\u3010\u5fc5\u987b\u3011\u654f\u611f\u6570\u636e\u8f93\u51fa<\/h4>\n<ul>\n<li>\u53ea\u8f93\u51fa\u5fc5\u8981\u7684\u6700\u5c0f\u6570\u636e\u96c6\uff0c\u907f\u514d\u591a\u4f59\u5b57\u6bb5\u66b4\u9732\u5f15\u8d77\u654f\u611f\u4fe1\u606f\u6cc4\u9732<\/li>\n<li>\u4e0d\u80fd\u5728\u65e5\u5fd7\u4fdd\u5b58\u5bc6\u7801\uff08\u5305\u62ec\u660e\u6587\u5bc6\u7801\u548c\u5bc6\u6587\u5bc6\u7801\uff09\u3001\u5bc6\u94a5\u548c\u5176\u5b83\u654f\u611f\u4fe1\u606f<\/li>\n<li>\u5bf9\u4e8e\u5fc5\u987b\u8f93\u51fa\u7684\u654f\u611f\u4fe1\u606f\uff0c\u5fc5\u987b\u8fdb\u884c\u5408\u7406\u8131\u654f\u5c55\u793a<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc serve() {\n    http.HandleFunc(&quot;\/register&quot;, func(w http.ResponseWriter, r *http.Request) {\n        r.ParseForm()\n        user := r.Form.Get(&quot;user&quot;)\n        pw := r.Form.Get(&quot;password&quot;)\n\n        log.Printf(&quot;Registering new user %s with password %s.\\n&quot;, user, pw)\n    })\n    http.ListenAndServe(&quot;:80&quot;, nil)\n}\n\n\/\/ good\nfunc serve1() {\n    http.HandleFunc(&quot;\/register&quot;, func(w http.ResponseWriter, r *http.Request) {\n        r.ParseForm()\n        user := r.Form.Get(&quot;user&quot;)\n        pw := r.Form.Get(&quot;password&quot;)\n\n        log.Printf(&quot;Registering new user %s.\\n&quot;, user)\n\n        \/\/ ...\n        use(pw)\n    })\n    http.ListenAndServe(&quot;:80&quot;, nil)\n}<\/code><\/pre>\n<ul>\n<li>\u907f\u514d\u901a\u8fc7GET\u65b9\u6cd5\u3001\u4ee3\u7801\u6ce8\u91ca\u3001\u81ea\u52a8\u586b\u5145\u3001\u7f13\u5b58\u7b49\u65b9\u5f0f\u6cc4\u9732\u654f\u611f\u4fe1\u606f<\/li>\n<\/ul>\n<h4>1.5.3\u3010\u5fc5\u987b\u3011\u654f\u611f\u6570\u636e\u5b58\u50a8<\/h4>\n<ul>\n<li>\u654f\u611f\u6570\u636e\u5e94\u4f7f\u7528SHA2\u3001RSA\u7b49\u7b97\u6cd5\u8fdb\u884c\u52a0\u5bc6\u5b58\u50a8<\/li>\n<li>\u654f\u611f\u6570\u636e\u5e94\u4f7f\u7528\u72ec\u7acb\u7684\u5b58\u50a8\u5c42\uff0c\u5e76\u5728\u8bbf\u95ee\u5c42\u5f00\u542f\u8bbf\u95ee\u63a7\u5236<\/li>\n<li>\u5305\u542b\u654f\u611f\u4fe1\u606f\u7684\u4e34\u65f6\u6587\u4ef6\u6216\u7f13\u5b58\u4e00\u65e6\u4e0d\u518d\u9700\u8981\u5e94\u7acb\u523b\u5220\u9664<\/li>\n<\/ul>\n<h4>1.5.4\u3010\u5fc5\u987b\u3011\u5f02\u5e38\u5904\u7406\u548c\u65e5\u5fd7\u8bb0\u5f55<\/h4>\n<ul>\n<li>\u5e94\u5408\u7406\u4f7f\u7528panic\u3001recover\u3001defer\u5904\u7406\u7cfb\u7edf\u5f02\u5e38\uff0c\u907f\u514d\u51fa\u9519\u4fe1\u606f\u8f93\u51fa\u5230\u524d\u7aef<\/li>\n<\/ul>\n<pre><code class=\"language-go\">defer func () {\n    if r := recover(); r != nil {\n        fmt.Println(&quot;Recovered in start()&quot;)\n    }\n}()<\/code><\/pre>\n<ul>\n<li>\u5bf9\u5916\u73af\u5883\u7981\u6b62\u5f00\u542fdebug\u6a21\u5f0f\uff0c\u6216\u5c06\u7a0b\u5e8f\u8fd0\u884c\u65e5\u5fd7\u8f93\u51fa\u5230\u524d\u7aef<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">\/\/ bad\ndlv --listen=:2345 --headless=true --api-version=2 debug test.go\n\/\/ good\ndlv debug test.go<\/code><\/pre>\n<p><a id=\"1.1.6\"><\/a><\/p>\n<h3>1.6 \u52a0\u5bc6\u89e3\u5bc6<\/h3>\n<h4>1.6.1\u3010\u5fc5\u987b\u3011\u4e0d\u5f97\u786c\u7f16\u7801\u5bc6\u7801\/\u5bc6\u94a5<\/h4>\n<ul>\n<li>\u5728\u8fdb\u884c\u7528\u6237\u767b\u9646\uff0c\u52a0\u89e3\u5bc6\u7b97\u6cd5\u7b49\u64cd\u4f5c\u65f6\uff0c\u4e0d\u5f97\u5728\u4ee3\u7801\u91cc\u786c\u7f16\u7801\u5bc6\u94a5\u6216\u5bc6\u7801\uff0c\u53ef\u901a\u8fc7\u53d8\u6362\u7b97\u6cd5\u6216\u8005\u914d\u7f6e\u7b49\u65b9\u5f0f\u8bbe\u7f6e\u5bc6\u7801\u6216\u8005\u5bc6\u94a5\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nconst (\n    user     = &quot;dbuser&quot;\n    password = &quot;s3cretp4ssword&quot;\n)\n\nfunc connect() *sql.DB {\n    connStr := fmt.Sprintf(&quot;postgres:\/\/%s:%s@localhost\/pqgotest&quot;, user, password)\n    db, err := sql.Open(&quot;postgres&quot;, connStr)\n    if err != nil {\n        return nil\n    }\n    return db\n}\n\n\/\/ bad\nvar (\n    commonkey = []byte(&quot;0123456789abcdef&quot;)\n)\n\nfunc AesEncrypt(plaintext string) (string, error) {\n    block, err := aes.NewCipher(commonkey)\n    if err != nil {\n        return &quot;&quot;, err\n    }\n}<\/code><\/pre>\n<h4>1.6.2\u3010\u5fc5\u987b\u3011\u5bc6\u94a5\u5b58\u50a8\u5b89\u5168<\/h4>\n<ul>\n<li>\u5728\u4f7f\u7528\u5bf9\u79f0\u5bc6\u7801\u7b97\u6cd5\u65f6\uff0c\u9700\u8981\u4fdd\u62a4\u597d\u52a0\u5bc6\u5bc6\u94a5\u3002\u5f53\u7b97\u6cd5\u6d89\u53ca\u654f\u611f\u3001\u4e1a\u52a1\u6570\u636e\u65f6\uff0c\u53ef\u901a\u8fc7\u975e\u5bf9\u79f0\u7b97\u6cd5\u534f\u5546\u52a0\u5bc6\u5bc6\u94a5\u3002\u5176\u4ed6\u8f83\u4e3a\u4e0d\u654f\u611f\u7684\u6570\u636e\u52a0\u5bc6\uff0c\u53ef\u4ee5\u901a\u8fc7\u53d8\u6362\u7b97\u6cd5\u7b49\u65b9\u5f0f\u4fdd\u62a4\u5bc6\u94a5\u3002<\/li>\n<\/ul>\n<h4>1.6.3\u3010\u63a8\u8350\u3011\u4e0d\u4f7f\u7528\u5f31\u5bc6\u7801\u7b97\u6cd5<\/h4>\n<ul>\n<li>\u5728\u4f7f\u7528\u52a0\u5bc6\u7b97\u6cd5\u65f6\uff0c\u4e0d\u5efa\u8bae\u4f7f\u7528\u52a0\u5bc6\u5f3a\u5ea6\u8f83\u5f31\u7684\u7b97\u6cd5\u3002<\/li>\n<\/ul>\n<pre><code>\/\/ bad\ncrypto\/des\uff0ccrypto\/md5\uff0ccrypto\/sha1\uff0ccrypto\/rc4\u7b49\u3002\n\n\/\/ good\ncrypto\/rsa\uff0ccrypto\/aes\u7b49\u3002<\/code><\/pre>\n<p><a id=\"1.1.7\"><\/a><\/p>\n<h3>1.7 \u6b63\u5219\u8868\u8fbe\u5f0f<\/h3>\n<h4>1.7.1\u3010\u63a8\u8350\u3011\u4f7f\u7528regexp\u8fdb\u884c\u6b63\u5219\u8868\u8fbe\u5f0f\u5339\u914d<\/h4>\n<ul>\n<li>\u6b63\u5219\u8868\u8fbe\u5f0f\u7f16\u5199\u4e0d\u6070\u5f53\u53ef\u88ab\u7528\u4e8eDoS\u653b\u51fb\uff0c\u9020\u6210\u670d\u52a1\u4e0d\u53ef\u7528\uff0c\u63a8\u8350\u4f7f\u7528regexp\u5305\u8fdb\u884c\u6b63\u5219\u8868\u8fbe\u5f0f\u5339\u914d\u3002regexp\u4fdd\u8bc1\u4e86\u7ebf\u6027\u65f6\u95f4\u6027\u80fd\u548c\u4f18\u96c5\u7684\u5931\u8d25\uff1a\u5bf9\u89e3\u6790\u5668\u3001\u7f16\u8bd1\u5668\u548c\u6267\u884c\u5f15\u64ce\u90fd\u8fdb\u884c\u4e86\u5185\u5b58\u9650\u5236\u3002\u4f46regexp\u4e0d\u652f\u6301\u4ee5\u4e0b\u6b63\u5219\u8868\u8fbe\u5f0f\u7279\u6027\uff0c\u5982\u4e1a\u52a1\u4f9d\u8d56\u8fd9\u4e9b\u7279\u6027\uff0c\u5219regexp\u4e0d\u9002\u5408\u4f7f\u7528\u3002\n<ul>\n<li>\u56de\u6eaf\u5f15\u7528<a href=\"https:\/\/www.regular-expressions.info\/backref.html\">Backreferences<\/a><\/li>\n<li>\u67e5\u770b<a href=\"https:\/\/www.regular-expressions.info\/lookaround.html\">Lookaround<\/a><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ good\nmatched, err := regexp.MatchString(`a.b`, &quot;aaxbb&quot;)\nfmt.Println(matched) \/\/ true\nfmt.Println(err)     \/\/ nil<\/code><\/pre>\n<p><a id=\"2\"><\/a><\/p>\n<h1>\u540e\u53f0\u7c7b<\/h1>\n<p><a id=\"2.1\"><\/a><\/p>\n<h2>1 \u4ee3\u7801\u5b9e\u73b0\u7c7b<\/h2>\n<p><a id=\"2.1.1\"><\/a><\/p>\n<h3>1.1 \u8f93\u5165\u6821\u9a8c<\/h3>\n<h4>1.1.1\u3010\u5fc5\u987b\u3011\u6309\u7c7b\u578b\u8fdb\u884c\u6570\u636e\u6821\u9a8c<\/h4>\n<ul>\n<li>\u6240\u6709\u5916\u90e8\u8f93\u5165\u7684\u53c2\u6570\uff0c\u5e94\u4f7f\u7528<code>validator<\/code>\u8fdb\u884c\u767d\u540d\u5355\u6821\u9a8c\uff0c\u6821\u9a8c\u5185\u5bb9\u5305\u62ec\u4f46\u4e0d\u9650\u4e8e\u6570\u636e\u957f\u5ea6\u3001\u6570\u636e\u8303\u56f4\u3001\u6570\u636e\u7c7b\u578b\u4e0e\u683c\u5f0f\uff0c\u6821\u9a8c\u4e0d\u901a\u8fc7\u7684\u5e94\u5f53\u62d2\u7edd<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ good\nimport (\n    &quot;fmt&quot;\n    &quot;github.com\/go-playground\/validator\/v10&quot;\n)\n\nvar validate *validator.Validate\n\nfunc validateVariable() {\n    myEmail := &quot;abc@tencent.com&quot;\n    errs := validate.Var(myEmail, &quot;required,email&quot;)\n    if errs != nil {\n        fmt.Println(errs)\n        return\n        \/\/\u505c\u6b62\u6267\u884c\n    }\n    \/\/ \u9a8c\u8bc1\u901a\u8fc7\uff0c\u7ee7\u7eed\u6267\u884c\n    ...\n}\n\nfunc main() {\n    validate = validator.New()\n    validateVariable()\n}<\/code><\/pre>\n<ul>\n<li>\u65e0\u6cd5\u901a\u8fc7\u767d\u540d\u5355\u6821\u9a8c\u7684\u5e94\u4f7f\u7528<code>html.EscapeString<\/code>\u3001<code>text\/template<\/code>\u6216<code>bluemonday<\/code>\u5bf9<code>&lt;, &gt;, &amp;, &#039;,&quot;<\/code>\u7b49\u5b57\u7b26\u8fdb\u884c\u8fc7\u6ee4\u6216\u7f16\u7801<\/li>\n<\/ul>\n<pre><code class=\"language-go\">import (\n    &quot;text\/template&quot;\n)\n\n\/\/ TestHTMLEscapeString HTML\u7279\u6b8a\u5b57\u7b26\u8f6c\u4e49\nfunc main(inputValue string) string {\n    escapedResult := template.HTMLEscapeString(inputValue)\n    return escapedResult\n}<\/code><\/pre>\n<p><a id=\"2.1.2\"><\/a><\/p>\n<h3>1.2 SQL\u64cd\u4f5c<\/h3>\n<h4>1.2.1\u3010\u5fc5\u987b\u3011SQL\u8bed\u53e5\u9ed8\u8ba4\u4f7f\u7528\u9884\u7f16\u8bd1\u5e76\u7ed1\u5b9a\u53d8\u91cf<\/h4>\n<ul>\n<li>\u4f7f\u7528<code>database\/sql<\/code>\u7684prepare\u3001Query\u6216\u4f7f\u7528GORM\u7b49ORM\u6267\u884cSQL\u64cd\u4f5c<\/li>\n<\/ul>\n<pre><code class=\"language-go\">import (\n    &quot;github.com\/jinzhu\/gorm&quot;\n    _ &quot;github.com\/jinzhu\/gorm\/dialects\/sqlite&quot;\n)\n\ntype Product struct {\n    gorm.Model\n    Code  string\n    Price uint\n}\n\n...\nvar product Product\n...\ndb.First(&amp;product, 1)<\/code><\/pre>\n<ul>\n<li>\u4f7f\u7528\u53c2\u6570\u5316\u67e5\u8be2\uff0c\u7981\u6b62\u62fc\u63a5SQL\u8bed\u53e5\uff0c\u53e6\u5916\u5bf9\u4e8e\u4f20\u5165\u53c2\u6570\u7528\u4e8eorder by\u6216\u8868\u540d\u7684\u9700\u8981\u901a\u8fc7\u6821\u9a8c<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nimport (\n    &quot;database\/sql&quot;\n    &quot;fmt&quot;\n    &quot;net\/http&quot;\n)\n\nfunc handler(db *sql.DB, req *http.Request) {\n    q := fmt.Sprintf(&quot;SELECT ITEM,PRICE FROM PRODUCT WHERE ITEM_CATEGORY=&#039;%s&#039; ORDER BY PRICE&quot;,\n        req.URL.Query()[&quot;category&quot;])\n    db.Query(q)\n}\n\n\/\/ good\nfunc handlerGood(db *sql.DB, req *http.Request) {\n    \/\/ \u4f7f\u7528?\u5360\u4f4d\u7b26\n    q := &quot;SELECT ITEM,PRICE FROM PRODUCT WHERE ITEM_CATEGORY=&#039;?&#039; ORDER BY PRICE&quot;\n    db.Query(q, req.URL.Query()[&quot;category&quot;])\n}<\/code><\/pre>\n<p><a id=\"2.1.3\"><\/a><\/p>\n<h3>1.3 \u7f51\u7edc\u8bf7\u6c42<\/h3>\n<h4>1.3.1\u3010\u5fc5\u987b\u3011\u8d44\u6e90\u8bf7\u6c42\u8fc7\u6ee4\u9a8c\u8bc1<\/h4>\n<ul>\n<li>\n<p>\u4f7f\u7528<code>&quot;net\/http&quot;<\/code>\u4e0b\u7684\u65b9\u6cd5<code>http.Get(url)<\/code>\u3001<code>http.Post(url, contentType, body)<\/code>\u3001<code>http.Head(url)<\/code>\u3001<code>http.PostForm(url, data)<\/code>\u3001<code>http.Do(req)<\/code>\u65f6\uff0c\u5982\u53d8\u91cf\u503c\u5916\u90e8\u53ef\u63a7\uff08\u6307\u4ece\u53c2\u6570\u4e2d\u52a8\u6001\u83b7\u53d6\uff09\uff0c\u5e94\u5bf9\u8bf7\u6c42\u76ee\u6807\u8fdb\u884c\u4e25\u683c\u7684\u5b89\u5168\u6821\u9a8c\u3002<\/p>\n<\/li>\n<li>\n<p>\u5982\u8bf7\u6c42\u8d44\u6e90\u57df\u540d\u5f52\u5c5e\u56fa\u5b9a\u7684\u8303\u56f4\uff0c\u5982\u53ea\u5141\u8bb8<code>a.qq.com<\/code>\u548c<code>b.qq.com<\/code>\uff0c\u5e94\u505a\u767d\u540d\u5355\u9650\u5236\u3002\u5982\u4e0d\u9002\u7528\u767d\u540d\u5355\uff0c\u5219\u63a8\u8350\u7684\u6821\u9a8c\u903b\u8f91\u6b65\u9aa4\u662f\uff1a<\/p>\n<ul>\n<li>\n<p>\u7b2c 1 \u6b65\u3001\u53ea\u5141\u8bb8HTTP\u6216HTTPS\u534f\u8bae<\/p>\n<\/li>\n<li>\n<p>\u7b2c 2 \u6b65\u3001\u89e3\u6790\u76ee\u6807URL\uff0c\u83b7\u53d6\u5176HOST<\/p>\n<\/li>\n<li>\n<p>\u7b2c 3 \u6b65\u3001\u89e3\u6790HOST\uff0c\u83b7\u53d6HOST\u6307\u5411\u7684IP\u5730\u5740\u8f6c\u6362\u6210Long\u578b<\/p>\n<\/li>\n<li>\n<p>\u7b2c 4 \u6b65\u3001\u68c0\u67e5IP\u5730\u5740\u662f\u5426\u4e3a\u5185\u7f51IP\uff0c\u7f51\u6bb5\u6709\uff1a<\/p>\n<\/li>\n<\/ul>\n<pre><code>\/\/ \u4ee5RFC\u5b9a\u4e49\u7684\u4e13\u6709\u7f51\u7edc\u4e3a\u4f8b\uff0c\u5982\u6709\u81ea\u5b9a\u4e49\u79c1\u6709\u7f51\u6bb5\u4ea6\u5e94\u52a0\u5165\u7981\u6b62\u8bbf\u95ee\u5217\u8868\u3002\n10.0.0.0\/8\n172.16.0.0\/12\n192.168.0.0\/16\n127.0.0.0\/8<\/code><\/pre>\n<ul>\n<li>\n<p>\u7b2c 5 \u6b65\u3001\u8bf7\u6c42URL<\/p>\n<\/li>\n<li>\n<p>\u7b2c 6 \u6b65\u3001\u5982\u6709\u8df3\u8f6c\uff0c\u8df3\u8f6c\u540e\u6267\u884c1\uff0c\u5426\u5219\u7ed1\u5b9a\u7ecf\u6821\u9a8c\u7684ip\u548c\u57df\u540d\uff0c\u5bf9URL\u53d1\u8d77\u8bf7\u6c42<\/p>\n<\/li>\n<\/ul>\n<\/li>\n<li>\n<p>\u5b98\u65b9\u5e93<code>encoding\/xml<\/code>\u4e0d\u652f\u6301\u5916\u90e8\u5b9e\u4f53\u5f15\u7528\uff0c\u4f7f\u7528\u8be5\u5e93\u53ef\u907f\u514dxxe\u6f0f\u6d1e<\/p>\n<\/li>\n<\/ul>\n<pre><code class=\"language-go\">import (\n    &quot;encoding\/xml&quot;\n    &quot;fmt&quot;\n    &quot;os&quot;\n)\n\nfunc main() {\n    type Person struct {\n        XMLName  xml.Name `xml:&quot;person&quot;`\n        Id       int      `xml:&quot;id,attr&quot;`\n        UserName string   `xml:&quot;name&gt;first&quot;`\n        Comment  string   `xml:&quot;,comment&quot;`\n    }\n\n    v := &amp;Person{Id: 13, UserName: &quot;John&quot;}\n    v.Comment = &quot; Need more details. &quot;\n\n    enc := xml.NewEncoder(os.Stdout)\n    enc.Indent(&quot;  &quot;, &quot;    &quot;)\n    if err := enc.Encode(v); err != nil {\n        fmt.Printf(&quot;error: %v\\n&quot;, err)\n    }\n\n}<\/code><\/pre>\n<p><a id=\"2.1.4\"><\/a><\/p>\n<h3>1.4 \u670d\u52a1\u5668\u7aef\u6e32\u67d3<\/h3>\n<h4>1.4.1\u3010\u5fc5\u987b\u3011\u6a21\u677f\u6e32\u67d3\u8fc7\u6ee4\u9a8c\u8bc1<\/h4>\n<ul>\n<li>\u4f7f\u7528<code>text\/template<\/code>\u6216\u8005<code>html\/template<\/code>\u6e32\u67d3\u6a21\u677f\u65f6\u7981\u6b62\u5c06\u5916\u90e8\u8f93\u5165\u53c2\u6570\u5f15\u5165\u6a21\u677f\uff0c\u6216\u4ec5\u5141\u8bb8\u5f15\u5165\u767d\u540d\u5355\u5185\u5b57\u7b26\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc handler(w http.ResponseWriter, r *http.Request) {\n    r.ParseForm()\n    x := r.Form.Get(&quot;name&quot;)\n\n    var tmpl = `&lt;!DOCTYPE html&gt;&lt;html&gt;&lt;body&gt;\n    &lt;form action=&quot;\/&quot; method=&quot;post&quot;&gt;\n        First name:&lt;br&gt;\n    &lt;input type=&quot;text&quot; name=&quot;name&quot; value=&quot;&quot;&gt;\n    &lt;input type=&quot;submit&quot; value=&quot;Submit&quot;&gt;\n    &lt;\/form&gt;&lt;p&gt;` + x + ` &lt;\/p&gt;&lt;\/body&gt;&lt;\/html&gt;`\n\n    t := template.New(&quot;main&quot;)\n    t, _ = t.Parse(tmpl)\n    t.Execute(w, &quot;Hello&quot;)\n}\n\n\/\/ good\nimport (\n    &quot;fmt&quot;\n    &quot;github.com\/go-playground\/validator\/v10&quot;\n)\n\nvar validate *validator.Validate\nvalidate = validator.New()\n\nfunc validateVariable(val) {\n    errs := validate.Var(val, &quot;gte=1,lte=100&quot;) \/\/ \u9650\u5236\u5fc5\u987b\u662f1-100\u7684\u6b63\u6574\u6570\n    if errs != nil {\n        fmt.Println(errs)\n        return false\n    }\n    return true\n}\n\nfunc handler(w http.ResponseWriter, r *http.Request) {\n    r.ParseForm()\n    x := r.Form.Get(&quot;name&quot;)\n\n    if validateVariable(x) {\n        var tmpl = `&lt;!DOCTYPE html&gt;&lt;html&gt;&lt;body&gt;\n            &lt;form action=&quot;\/&quot; method=&quot;post&quot;&gt;\n            First name:&lt;br&gt;\n            &lt;input type=&quot;text&quot; name=&quot;name&quot; value=&quot;&quot;&gt;\n            &lt;input type=&quot;submit&quot; value=&quot;Submit&quot;&gt;\n            &lt;\/form&gt;&lt;p&gt;` + x + ` &lt;\/p&gt;&lt;\/body&gt;&lt;\/html&gt;`\n        t := template.New(&quot;main&quot;)\n        t, _ = t.Parse(tmpl)\n        t.Execute(w, &quot;Hello&quot;)\n    } else {\n        \/\/ ...\n    }\n}\n<\/code><\/pre>\n<p><a id=\"2.1.5\"><\/a><\/p>\n<h3>1.5 Web\u8de8\u57df<\/h3>\n<h4>1.5.1\u3010\u5fc5\u987b\u3011\u8de8\u57df\u8d44\u6e90\u5171\u4eabCORS\u9650\u5236\u8bf7\u6c42\u6765\u6e90<\/h4>\n<ul>\n<li>CORS\u8bf7\u6c42\u4fdd\u62a4\u4e0d\u5f53\u53ef\u5bfc\u81f4\u654f\u611f\u4fe1\u606f\u6cc4\u6f0f\uff0c\u56e0\u6b64\u5e94\u5f53\u4e25\u683c\u8bbe\u7f6eAccess-Control-Allow-Origin\u4f7f\u7528\u540c\u6e90\u7b56\u7565\u8fdb\u884c\u4fdd\u62a4\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ good\nc := cors.New(cors.Options{\n    AllowedOrigins:   []string{&quot;http:\/\/qq.com&quot;, &quot;https:\/\/qq.com&quot;},\n    AllowCredentials: true,\n    Debug:            false,\n})\n\n\/\/ \u5f15\u5165\u4e2d\u95f4\u4ef6\nhandler = c.Handler(handler)<\/code><\/pre>\n<p><a id=\"2.1.6\"><\/a><\/p>\n<h3>1.6 \u54cd\u5e94\u8f93\u51fa<\/h3>\n<h4>1.6.1 \u3010\u5fc5\u987b\u3011\u8bbe\u7f6e\u6b63\u786e\u7684HTTP\u54cd\u5e94\u5305\u7c7b\u578b<\/h4>\n<ul>\n<li>\u54cd\u5e94\u5934Content-Type\u4e0e\u5b9e\u9645\u54cd\u5e94\u5185\u5bb9\uff0c\u5e94\u4fdd\u6301\u4e00\u81f4\u3002\u5982\uff1aAPI\u54cd\u5e94\u6570\u636e\u7c7b\u578b\u662fjson\uff0c\u5219\u54cd\u5e94\u5934\u4f7f\u7528<code>application\/json<\/code>\uff1b\u82e5\u4e3axml\uff0c\u5219\u8bbe\u7f6e\u4e3a<code>text\/xml<\/code>\u3002<\/li>\n<\/ul>\n<h4>1.6.2 \u3010\u5fc5\u987b\u3011\u6dfb\u52a0\u5b89\u5168\u54cd\u5e94\u5934<\/h4>\n<ul>\n<li>\u6240\u6709\u63a5\u53e3\u3001\u9875\u9762\uff0c\u6dfb\u52a0\u54cd\u5e94\u5934 <code>X-Content-Type-Options: nosniff<\/code>\u3002<\/li>\n<li>\u6240\u6709\u63a5\u53e3\u3001\u9875\u9762\uff0c\u6dfb\u52a0\u54cd\u5e94\u5934<code>X-Frame-Options <\/code>\u3002\u6309\u9700\u5408\u7406\u8bbe\u7f6e\u5176\u5141\u8bb8\u8303\u56f4\uff0c\u5305\u62ec\uff1a<code>DENY<\/code>\u3001<code>SAMEORIGIN<\/code>\u3001<code>ALLOW-FROM origin<\/code>\u3002\u7528\u6cd5\u53c2\u8003\uff1a<a href=\"https:\/\/developer.mozilla.org\/zh-CN\/docs\/Web\/HTTP\/X-Frame-Options\">MDN\u6587\u6863<\/a><\/li>\n<\/ul>\n<h4>1.6.3\u3010\u5fc5\u987b\u3011\u5916\u90e8\u8f93\u5165\u62fc\u63a5\u5230HTTP\u54cd\u5e94\u5934\u4e2d\u9700\u8fdb\u884c\u8fc7\u6ee4<\/h4>\n<ul>\n<li>\u5e94\u5c3d\u91cf\u907f\u514d\u5916\u90e8\u53ef\u63a7\u53c2\u6570\u62fc\u63a5\u5230HTTP\u54cd\u5e94\u5934\u4e2d\uff0c\u5982\u4e1a\u52a1\u9700\u8981\u5219\u9700\u8981\u8fc7\u6ee4\u6389<code>\\r<\/code>\u3001<code>\\n<\/code>\u7b49\u6362\u884c\u7b26\uff0c\u6216\u8005\u62d2\u7edd\u643a\u5e26\u6362\u884c\u7b26\u53f7\u7684\u5916\u90e8\u8f93\u5165\u3002<\/li>\n<\/ul>\n<h4>1.6.4\u3010\u5fc5\u987b\u3011\u5916\u90e8\u8f93\u5165\u62fc\u63a5\u5230response\u9875\u9762\u524d\u8fdb\u884c\u7f16\u7801\u5904\u7406<\/h4>\n<ul>\n<li>\u76f4\u51fahtml\u9875\u9762\u6216\u4f7f\u7528\u6a21\u677f\u751f\u6210html\u9875\u9762\u7684\uff0c\u63a8\u8350\u4f7f\u7528<code>text\/template<\/code>\u81ea\u52a8\u7f16\u7801\uff0c\u6216\u8005\u4f7f\u7528<code>html.EscapeString<\/code>\u6216<code>text\/template<\/code>\u5bf9<code>&lt;, &gt;, &amp;, &#039;,&quot;<\/code>\u7b49\u5b57\u7b26\u8fdb\u884c\u7f16\u7801\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">import (\n    &quot;html\/template&quot;\n)\n\nfunc outtemplate(w http.ResponseWriter, r *http.Request) {\n    param1 := r.URL.Query().Get(&quot;param1&quot;)\n    tmpl := template.New(&quot;hello&quot;)\n    tmpl, _ = tmpl.Parse(`{{define &quot;T&quot;}}{{.}}{{end}}`)\n    tmpl.ExecuteTemplate(w, &quot;T&quot;, param1)\n}<\/code><\/pre>\n<p><a id=\"2.1.7\"><\/a><\/p>\n<h3>1.7 \u4f1a\u8bdd\u7ba1\u7406<\/h3>\n<h4>1.7.1\u3010\u5fc5\u987b\u3011\u5b89\u5168\u7ef4\u62a4session\u4fe1\u606f<\/h4>\n<ul>\n<li>\u7528\u6237\u767b\u5f55\u65f6\u5e94\u91cd\u65b0\u751f\u6210session\uff0c\u9000\u51fa\u767b\u5f55\u540e\u5e94\u6e05\u7406session\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">import (\n    &quot;github.com\/gorilla\/handlers&quot;\n    &quot;github.com\/gorilla\/mux&quot;\n    &quot;net\/http&quot;\n)\n\n\/\/ \u521b\u5efacookie\nfunc setToken(res http.ResponseWriter, req *http.Request) {\n    expireToken := time.Now().Add(time.Minute * 30).Unix()\n    expireCookie := time.Now().Add(time.Minute * 30)\n\n    \/\/...\n\n    cookie := http.Cookie{\n        Name:     &quot;Auth&quot;,\n        Value:    signedToken,\n        Expires:  expireCookie, \/\/ \u8fc7\u671f\u5931\u6548\n        HttpOnly: true,\n        Path:     &quot;\/&quot;,\n        Domain:   &quot;127.0.0.1&quot;,\n        Secure:   true,\n    }\n\n    http.SetCookie(res, &amp;cookie)\n    http.Redirect(res, req, &quot;\/profile&quot;, 307)\n}\n\n\/\/ \u5220\u9664cookie\nfunc logout(res http.ResponseWriter, req *http.Request) {\n    deleteCookie := http.Cookie{\n        Name:    &quot;Auth&quot;,\n        Value:   &quot;none&quot;,\n        Expires: time.Now(),\n    }\n    http.SetCookie(res, &amp;deleteCookie)\n    return\n}<\/code><\/pre>\n<h4>1.7.2\u3010\u5fc5\u987b\u3011CSRF\u9632\u62a4<\/h4>\n<ul>\n<li>\u6d89\u53ca\u7cfb\u7edf\u654f\u611f\u64cd\u4f5c\u6216\u53ef\u8bfb\u53d6\u654f\u611f\u4fe1\u606f\u7684\u63a5\u53e3\u5e94\u6821\u9a8c<code>Referer<\/code>\u6216\u6dfb\u52a0<code>csrf_token<\/code>\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ good\nimport (\n    &quot;github.com\/gorilla\/csrf&quot;\n    &quot;github.com\/gorilla\/mux&quot;\n    &quot;net\/http&quot;\n)\n\nfunc main() {\n    r := mux.NewRouter()\n    r.HandleFunc(&quot;\/signup&quot;, ShowSignupForm)\n    r.HandleFunc(&quot;\/signup\/post&quot;, SubmitSignupForm)\n    \/\/ \u4f7f\u7528csrf_token\u9a8c\u8bc1\n    http.ListenAndServe(&quot;:8000&quot;,\n        csrf.Protect([]byte(&quot;32-byte-long-auth-key&quot;))(r))\n}<\/code><\/pre>\n<p><a id=\"2.1.8\"><\/a><\/p>\n<h3>1.8 \u8bbf\u95ee\u63a7\u5236<\/h3>\n<h4>1.8.1\u3010\u5fc5\u987b\u3011\u9ed8\u8ba4\u9274\u6743<\/h4>\n<ul>\n<li>\n<p>\u9664\u975e\u8d44\u6e90\u5b8c\u5168\u53ef\u5bf9\u5916\u5f00\u653e\uff0c\u5426\u5219\u7cfb\u7edf\u9ed8\u8ba4\u8fdb\u884c\u8eab\u4efd\u8ba4\u8bc1\uff0c\u4f7f\u7528\u767d\u540d\u5355\u7684\u65b9\u5f0f\u653e\u5f00\u4e0d\u9700\u8981\u8ba4\u8bc1\u7684\u63a5\u53e3\u6216\u9875\u9762\u3002<\/p>\n<\/li>\n<li>\n<p>\u6839\u636e\u8d44\u6e90\u7684\u673a\u5bc6\u7a0b\u5ea6\u548c\u7528\u6237\u89d2\u8272\uff0c\u4ee5\u6700\u5c0f\u6743\u9650\u539f\u5219\uff0c\u8bbe\u7f6e\u4e0d\u540c\u7ea7\u522b\u7684\u6743\u9650\uff0c\u5982\u5b8c\u5168\u516c\u5f00\u3001\u767b\u5f55\u53ef\u8bfb\u3001\u767b\u5f55\u53ef\u5199\u3001\u7279\u5b9a\u7528\u6237\u53ef\u8bfb\u3001\u7279\u5b9a\u7528\u6237\u53ef\u5199\u7b49<\/p>\n<\/li>\n<li>\n<p>\u6d89\u53ca\u7528\u6237\u81ea\u8eab\u76f8\u5173\u7684\u6570\u636e\u7684\u8bfb\u5199\u5fc5\u987b\u9a8c\u8bc1\u767b\u5f55\u6001\u7528\u6237\u8eab\u4efd\u53ca\u5176\u6743\u9650\uff0c\u907f\u514d\u8d8a\u6743\u64cd\u4f5c<\/p>\n<pre><code class=\"language-sql\">-- \u4f2a\u4ee3\u7801\nselect id from table where id=:id and userid=session.userid<\/code><\/pre>\n<\/li>\n<li>\n<p>\u6ca1\u6709\u72ec\u7acb\u8d26\u53f7\u4f53\u7cfb\u7684\u5916\u7f51\u670d\u52a1\u4f7f\u7528<code>QQ<\/code>\u6216<code>\u5fae\u4fe1<\/code>\u767b\u5f55\uff0c\u5185\u7f51\u670d\u52a1\u4f7f\u7528<code>\u7edf\u4e00\u767b\u5f55\u670d\u52a1<\/code>\u767b\u5f55\uff0c\u5176\u4ed6\u4f7f\u7528\u8d26\u53f7\u5bc6\u7801\u767b\u5f55\u7684\u670d\u52a1\u9700\u8981\u589e\u52a0\u9a8c\u8bc1\u7801\u7b49\u4e8c\u6b21\u9a8c\u8bc1<\/p>\n<\/li>\n<\/ul>\n<p><a id=\"2.1.9\"><\/a><\/p>\n<h3>1.9 \u5e76\u53d1\u4fdd\u62a4<\/h3>\n<h4>1.9.1\u3010\u5fc5\u987b\u3011\u7981\u6b62\u5728\u95ed\u5305\u4e2d\u76f4\u63a5\u8c03\u7528\u5faa\u73af\u53d8\u91cf<\/h4>\n<ul>\n<li>\u5728\u5faa\u73af\u4e2d\u542f\u52a8\u534f\u7a0b\uff0c\u5f53\u534f\u7a0b\u4e2d\u4f7f\u7528\u5230\u4e86\u5faa\u73af\u7684\u7d22\u5f15\u503c\uff0c\u7531\u4e8e\u591a\u4e2a\u534f\u7a0b\u540c\u65f6\u4f7f\u7528\u540c\u4e00\u4e2a\u53d8\u91cf\u4f1a\u4ea7\u751f\u6570\u636e\u7ade\u4e89\uff0c\u9020\u6210\u6267\u884c\u7ed3\u679c\u5f02\u5e38\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc main() {\n    runtime.GOMAXPROCS(runtime.NumCPU())\n    var group sync.WaitGroup\n\n    for i := 0; i &lt; 5; i++ {\n        group.Add(1)\n        go func() {\n            defer group.Done()\n            fmt.Printf(&quot;%-2d&quot;, i) \/\/ \u8fd9\u91cc\u6253\u5370\u7684i\u4e0d\u662f\u6240\u671f\u671b\u7684\n        }()\n    }\n    group.Wait()\n}\n\n\/\/ good\nfunc main() {\n    runtime.GOMAXPROCS(runtime.NumCPU())\n    var group sync.WaitGroup\n\n    for i := 0; i &lt; 5; i++ {\n        group.Add(1)\n        go func(j int) {\n            defer func() {\n                if r := recover(); r != nil {\n                    fmt.Println(&quot;Recovered in start()&quot;)\n                }\n                group.Done()\n            }()\n            fmt.Printf(&quot;%-2d&quot;, j) \/\/ \u95ed\u5305\u5185\u90e8\u4f7f\u7528\u5c40\u90e8\u53d8\u91cf\n        }(i) \/\/ \u628a\u5faa\u73af\u53d8\u91cf\u663e\u5f0f\u5730\u4f20\u7ed9\u534f\u7a0b\n    }\n    group.Wait()\n}<\/code><\/pre>\n<h4>1.9.2\u3010\u5fc5\u987b\u3011\u7981\u6b62\u5e76\u53d1\u5199map<\/h4>\n<ul>\n<li>\u5e76\u53d1\u5199map\u5bb9\u6613\u9020\u6210\u7a0b\u5e8f\u5d29\u6e83\u5e76\u5f02\u5e38\u9000\u51fa\uff0c\u5efa\u8bae\u52a0\u9501\u4fdd\u62a4<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ bad\nfunc main() {\n    m := make(map[int]int)\n    \/\/ \u5e76\u53d1\u8bfb\u5199\n    go func() {\n        for {\n            _ = m[1]\n        }\n    }()\n    go func() {\n        for {\n            m[2] = 1\n        }\n    }()\n    select {}\n}<\/code><\/pre>\n<h4>1.9.3\u3010\u5fc5\u987b\u3011\u786e\u4fdd\u5e76\u53d1\u5b89\u5168<\/h4>\n<p>\u654f\u611f\u64cd\u4f5c\u5982\u679c\u672a\u4f5c\u5e76\u53d1\u5b89\u5168\u9650\u5236\uff0c\u53ef\u5bfc\u81f4\u6570\u636e\u8bfb\u5199\u5f02\u5e38\uff0c\u9020\u6210\u4e1a\u52a1\u903b\u8f91\u9650\u5236\u88ab\u7ed5\u8fc7\u3002\u53ef\u901a\u8fc7\u540c\u6b65\u9501\u6216\u8005\u539f\u5b50\u64cd\u4f5c\u8fdb\u884c\u9632\u62a4\u3002<\/p>\n<p>\u901a\u8fc7\u540c\u6b65\u9501\u5171\u4eab\u5185\u5b58<\/p>\n<pre><code class=\"language-go\">\/\/ good\nvar count int\n\nfunc Count(lock *sync.Mutex) {\n    lock.Lock() \/\/ \u52a0\u5199\u9501\n    count++\n    fmt.Println(count)\n    lock.Unlock() \/\/ \u89e3\u5199\u9501\uff0c\u4efb\u4f55\u4e00\u4e2aLock()\u6216RLock()\u5747\u9700\u8981\u4fdd\u8bc1\u5bf9\u5e94\u6709Unlock()\u6216RUnlock()\n}\n\nfunc main() {\n    lock := &amp;sync.Mutex{}\n    for i := 0; i &lt; 10; i++ {\n        go Count(lock) \/\/ \u4f20\u9012\u6307\u9488\u662f\u4e3a\u4e86\u9632\u6b62\u51fd\u6570\u5185\u7684\u9501\u548c\u8c03\u7528\u9501\u4e0d\u4e00\u81f4\n    }\n    for {\n        lock.Lock()\n        c := count\n        lock.Unlock()\n        runtime.Gosched() \/\/ \u4ea4\u51fa\u65f6\u95f4\u7247\u7ed9\u534f\u7a0b\n        if c &gt; 10 {\n            break\n        }\n    }\n}<\/code><\/pre>\n<ul>\n<li>\u4f7f\u7528<code>sync\/atomic<\/code>\u6267\u884c\u539f\u5b50\u64cd\u4f5c<\/li>\n<\/ul>\n<pre><code class=\"language-go\">\/\/ good\nimport (\n    &quot;sync&quot;\n    &quot;sync\/atomic&quot;\n)\n\nfunc main() {\n    type Map map[string]string\n    var m atomic.Value\n    m.Store(make(Map))\n    var mu sync.Mutex \/\/ used only by writers\n    read := func(key string) (val string) {\n        m1 := m.Load().(Map)\n        return m1[key]\n    }\n    insert := func(key, val string) {\n        mu.Lock() \/\/ \u4e0e\u6f5c\u5728\u5199\u5165\u540c\u6b65\n        defer mu.Unlock()\n        m1 := m.Load().(Map) \/\/ \u5bfc\u5165struct\u5f53\u524d\u6570\u636e\n        m2 := make(Map)      \/\/ \u521b\u5efa\u65b0\u503c\n        for k, v := range m1 {\n            m2[k] = v\n        }\n        m2[key] = val\n        m.Store(m2) \/\/ \u7528\u65b0\u7684\u66ff\u4ee3\u5f53\u524d\u5bf9\u8c61\n    }\n    _, _ = read, insert\n}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u901a\u7528\u7c7b 1. \u4ee3\u7801\u5b9e\u73b0\u7c7b 1.1 \u5185\u5b58\u7ba1\u7406 1.1.1\u3010\u5fc5\u987b\u3011\u5207\u7247\u957f\u5ea6\u6821\u9a8c \u5728\u5bf9slice\u8fdb\u884c\u64cd\u4f5c\u65f6\uff0c\u5fc5\u987b\u5224\u65ad\u957f\u5ea6\u662f\u5426\u5408\u6cd5\uff0c\u9632\u6b62\u7a0b\u5e8fpa   \u2026 &#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0},"categories":[150],"tags":[],"_links":{"self":[{"href":"\/index.php?rest_route=\/wp\/v2\/posts\/2029"}],"collection":[{"href":"\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2029"}],"version-history":[{"count":1,"href":"\/index.php?rest_route=\/wp\/v2\/posts\/2029\/revisions"}],"predecessor-version":[{"id":2030,"href":"\/index.php?rest_route=\/wp\/v2\/posts\/2029\/revisions\/2030"}],"wp:attachment":[{"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2029"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2029"},{"taxonomy":"post_tag","embeddable":true,"href":"\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2029"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}