{"id":19,"date":"2026-02-15T19:53:36","date_gmt":"2026-02-15T11:53:36","guid":{"rendered":"http:\/\/43.138.147.217\/?p=19"},"modified":"2026-02-15T21:37:33","modified_gmt":"2026-02-15T13:37:33","slug":"%e5%9f%ba%e4%ba%8egolang%e5%ae%9e%e7%8e%b0%e5%8f%8d%e5%90%91%e4%bb%a3%e7%90%86%e6%9c%8d%e5%8a%a1%e5%99%a8%ef%bc%882%ef%bc%89%e8%b4%9f%e8%bd%bd%e5%9d%87%e8%a1%a1%e7%ae%97%e6%b3%95","status":"publish","type":"post","link":"https:\/\/fableary.top\/?p=19","title":{"rendered":"\u57fa\u4e8eGolang\u5b9e\u73b0\u53cd\u5411\u4ee3\u7406\u670d\u52a1\u5668\uff082\uff09\u8d1f\u8f7d\u5747\u8861\u7b97\u6cd5"},"content":{"rendered":"\n

\u56de\u987e\u4e0e\u76ee\u6807\uff1a<\/strong><\/p>\n\n\n\n

\u5728\u4e4b\u524d\u7684\u5b9e\u73b0\u4e2d\uff0c ReverseProxy \u51fd\u6570\u63a5\u6536\u4e00\u4e2a\u56fa\u5b9a\u7684 target *url.URL \u3002<\/p>\n\n\n\n

\u8981\u5b9e\u73b0\u8d1f\u8f7d\u5747\u8861\uff0c\u9700\u8981\uff1a<\/strong><\/p>\n\n\n\n

    \n
  1. \u7ba1\u7406\u4e00\u4e2a\u540e\u7aef\u5217\u8868\uff08\u652f\u6301\u591a\u4e2a\u76ee\u6807 URL \uff09\u3002<\/li>\n\n\n\n
  2. \u6839\u636e\u4e0d\u540c\u7684\u7b56\u7565\uff08\u8f6e\u8be2\u3001\u968f\u673a\u3001\u6700\u5c11\u8fde\u63a5\u3001IP \u54c8\u5e0c\uff09\u4ece\u5217\u8868\u4e2d\u9009\u62e9\u4e00\u4e2a\u76ee\u6807<\/li>\n\n\n\n
  3. \u4fdd\u8bc1\u5728\u591a goroutine \u5e76\u53d1\u4e0b\uff0c\u9009\u62e9\u8fc7\u7a0b\u662f\u5b89\u5168<\/strong>\u7684<\/li>\n<\/ol>\n\n\n\n

    \u4e00\u3001\u8bbe\u8ba1\u6570\u636e\u7ed3\u6784\uff1a<\/h3>\n\n\n\n

    1. \u540e\u7aef\u8282\u70b9\uff08Backend\uff09<\/h4>\n\n\n\n

    \u6bcf\u4e2a\u540e\u7aef\u9700\u8981\u5305\u542b\uff1a<\/p>\n\n\n\n

      \n
    • URL<\/code>\uff1a\u540e\u7aef\u7684\u5730\u5740\uff08\u6bd4\u5982 http:\/\/localhost:8001<\/code>\uff09<\/li>\n\n\n\n
    • Alive<\/code>\uff1a\u662f\u5426\u5065\u5eb7\uff08\u4e0b\u4e00\u9636\u6bb5\u5b9e\u73b0\uff0c\u5148\u9884\u7559\uff09<\/li>\n\n\n\n
    • Connections<\/code>\uff1a\u5f53\u524d\u6d3b\u8dc3\u8fde\u63a5\u6570\uff08\u7528\u4e8e\u201c\u6700\u5c11\u8fde\u63a5\u6570\u201d\u7b97\u6cd5\uff09<\/li>\n<\/ul>\n\n\n\n
      type Backend struct{\n\tURL *url.URL\n\tAlive bool \/\/ \u662f\u5426\u5b58\u6d3b\uff08\u5065\u5eb7\u68c0\u67e5\u7528\uff09\n\tConnections int64 \/\/ \u5f53\u524d\u6d3b\u8dc3\u8fde\u63a5\u6570\uff08\u539f\u5b50\u64cd\u4f5c\uff09\n}<\/code><\/pre>\n\n\n\n
      2. \u8d1f\u8f7d\u5747\u8861\u5668\uff08LoadBalancer\uff09<\/h4>\n\n\n\n
      \u8d1f\u8f7d\u5747\u8861\u5668\u7ba1\u7406\u6240\u6709\u540e\u7aef\uff0c\u5e76\u63d0\u4f9b\u9009\u62e9\u65b9\u6cd5\u3002<\/p>\n\n\n\n
      type LoadBalancer struct{\n\tbackends []*Backend\n\tcurrent uint64 \/\/ \u8f6e\u8be2\u7528\uff0c\u6307\u5411\u4e0b\u4e00\u4e2a\u8981\u9009\u62e9\u7684\u540e\u7aef\u7d22\u5f15\n\tmu sync.RWMutex \/\/ \u4fdd\u62a4 backends \u5207\u7247\uff08\u6bd4\u5982\u52a8\u6001\u589e\u5220\u540e\u7aef\uff09\n}<\/code><\/pre>\n\n\n\n
      3. \u521d\u59cb\u5316<\/h4>\n\n\n\n
      \u53ef\u4ee5\u4ece\u914d\u7f6e\u6587\u4ef6\u6216\u786c\u7f16\u7801\u521b\u5efa\u51e0\u4e2a\u540e\u7aef\uff1a<\/p>\n\n\n\n
      func NewLoadBalancer(urls []string) *LoadBalancer{\n\tvar backends []*Backend\n\tfor _, u := range urls{\n\t\tparsed, _ := url.Parse(u)\n\t\tbackends = append(backends, &Backend{\n\t\t\tURL: parsed,\n\t\t\tAlive: true,\n\t\t\tConnections: 0,\n\t\t})\n\t}\n\treturn &LoadBalancer{\n\t\tbackends: backends,\n\t\tcurrent: 0,\n\t}\n}<\/code><\/pre>\n\n\n\n
      \u4e8c\u3001\u5b9e\u73b0\u8d1f\u8f7d\u5747\u8861\u7b97\u6cd5<\/h3>\n\n\n\n
      1. \u8f6e\u8be2\uff08Round Robin\uff09<\/h4>\n\n\n\n
      \u8f6e\u8be2\u5c31\u662f\u6309\u7167\u987a\u5e8f\u8f6e\u6d41\u9009\u62e9\u540e\u7aef\u3002<\/p>\n\n\n\n
      \u5173\u952e\u5728\u4e8e\u5e76\u53d1\u5b89\u5168<\/strong>\uff1a\u591a\u4e2a\u8bf7\u6c42\u540c\u65f6\u8fdb\u6765\uff0c\u4e0d\u80fd\u90fd\u9009\u540c\u4e00\u4e2a\u3002<\/p>\n\n\n\n
      \u53ef\u4ee5\u5229\u7528\u539f\u5b50\u64cd\u4f5c<\/strong>\u6765\u9012\u589e\u7d22\u5f15\u3002<\/p>\n\n\n\n
      func (lb *LoadBalancer) NextRoundRobin() *Backend {\n\tlb.mu.RLock() \/\/ \u52a0\u8bfb\u9501\uff0c\u7981\u6b62\u5176\u4ed6 goroutine \u4fee\u6539 backends\n    defer lb.mu.RUnlock()\n\t\/\/ \u6ce8\u610f\u5230\uff1a\u4e00\u81f4\u6027\u54c8\u5e0c\u53ef\u4ee5\u907f\u514d\u8d8a\u754c\u95ee\u9898\uff0c\u540e\u7eed\u8fdb\u884c\u5b66\u4e60\n\n\tn := uint64(len(lb.backends))\n\tif n == 0{\n\t\treturn nil\n\t}\n\n\t\/\/ \u539f\u5b50\u5730\u589e\u52a0 current \uff0c\u5e76\u53d6\u6a21\n\tnext := atomic.AddUint64(&lb.current, 1) % n\n\n\treturn lb.backends[next]\n}<\/code><\/pre>\n\n\n\n
      2. \u968f\u673a\uff08Random\uff09<\/h4>\n\n\n\n
      \u968f\u673a\u9009\u62e9\u4e00\u4e2a\u540e\u7aef\u3002<\/p>\n\n\n\n
      \u8fd9\u91cc\u4f7f\u7528 math\/rand \u6765\u8fdb\u884c\u968f\u673a\u9009\u62e9\uff0c\u6ce8\u610f rand \u5305\u9ed8\u8ba4\u4e0d\u662f\u5e76\u53d1\u5b89\u5168\u7684\uff0c\u56e0\u6b64\u8fd9\u91cc\u91c7\u7528\u52a0\u9501\u4fdd\u62a4 rand \u8c03\u7528\u3002<\/p>\n\n\n\n
      var rngMu sync.Mutex\nfunc (lb *LoadBalancer) NextRandom() *Backend {\n\tlb.mu.RLock()\n\tdefer lb.mu.RUnlock()\n\n\tn := len(lb.backends)\n\tif n == 0{\n\t\treturn nil\n\t}\n\n\trngMu.Lock()\n\tidx := rand.Intn(n)\n\trngMu.Unlock()\n\n\t\/\/ \u66f4\u597d\u7684\u505a\u6cd5\uff1a\u4f7f\u7528 rand.New(rand.NewSource(time.Now().UnixNano())) \n\t\/\/ \u521b\u5efa\u4e00\u4e2a\u79c1\u6709\u7684\u968f\u673a\u6e90\uff0c\u5e76\u7528\u4e00\u4e2a sync.Mutex \u4fdd\u62a4\u5b83\n\n\treturn lb.backends[idx]\n}<\/code><\/pre>\n\n\n\n
      3. \u6700\u5c11\u8fde\u63a5\u6570\uff08Least Connections\uff09<\/h4>\n\n\n\n
      \u9009\u62e9\u5f53\u524d\u6d3b\u8dc3\u8fde\u63a5\u6570\u6700\u5c0f\u7684\u540e\u7aef\u3002<\/p>\n\n\n\n
      \u6d3b\u8dc3\u8fde\u63a5\u6570 Connections \u9700\u8981\u5728\u8f6c\u53d1\u8bf7\u6c42\u65f6\u589e\u52a0\uff0c\u5728\u8bf7\u6c42\u5b8c\u6210\u540e\u51cf\u5c11\u3002<\/p>\n\n\n\n
      func (lb *LoadBalancer) NextLeastConnections() *Backend {\n\tlb.mu.RLock()\n\tdefer lb.mu.RUnlock()\n\n\tvar selected *Backend\n\tvar minConns int64 = 1<<63 - 1\n\n\tfor _, b := range lb.backends {\n\t\tif !b.Alive {\n\t\t\tcontinue\n\t\t}\n\n\t\tconns := atomic.LoadInt64(&b.Connections)\n\t\tif conns < minConns {\n\t\t\tminConns = conns\n\t\t\tselected = b\n\t\t}\n\t}\n\n\treturn selected\n}<\/code><\/pre>\n\n\n\n
      4. IP \u54c8\u5e0c\uff08IP Hash\uff09<\/h4>\n\n\n\n
      \u6839\u636e\u5ba2\u6237\u7aef IP \u8ba1\u7b97\u54c8\u5e0c\u503c\uff0c\u7136\u540e\u6620\u5c04\u5230\u540e\u7aef\u3002<\/p>\n\n\n\n
      \u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u540c\u4e00\u4e2a\u5ba2\u6237\u7aef\u7684\u8bf7\u6c42\u603b\u662f\u6253\u5230\u540c\u4e00\u4e2a\u540e\u7aef\uff08\u5982\u679c\u540e\u7aef\u6570\u91cf\u4e0d\u53d8\u7684\u8bdd\uff09\u3002<\/p>\n\n\n\n
      func (lb *LoadBalancer) NextIPHash(ip string) *Backend {\n\tlb.mu.RLock()\n\tdefer lb.mu.RUnlock()\n\n\n\n\tn := len(lb.backends)\n\tif n == 0 {\n\t\treturn nil\n\t}\n\n\t\/\/ \u7b80\u5355\u7684\u54c8\u5e0c\uff1a\u628a IP \u5b57\u7b26\u4e32\u8f6c\u6210\u6574\u6570\u7136\u540e\u53d6\u6a21\n\th := fnv.New32a()\n\th.Write([]byte(ip))\n\thash := h.Sum32()\n\tidx := int(hash) % n\n\treturn lb.backends[idx]\n}<\/code><\/pre>\n\n\n\n
      \u6ce8\u610f\uff1a<\/strong>IP \u54c8\u5e0c\u9700\u8981\u5728\u53cd\u5411\u4ee3\u7406\u5904\u7406\u5668\u4e2d\u83b7\u53d6\u5ba2\u6237\u7aef IP \u3002\u53ef\u4ee5\u4ece r.RemoteAddr \u62ff\u5230\uff0c\u9700\u8981\u5206\u5272\u51fa IP \u3002\u5982\u679c\u6709 X-Forwarded-For \u5934\uff0c\u53ef\u80fd\u8fd8\u9700\u8981\u5904\u7406\u4ee3\u7406\u94fe\u7684\u60c5\u51b5\uff0c\u8fd9\u91cc\u7684\u5904\u7406\u5148\u76f4\u63a5\u4f7f\u7528 r.RemoteAddr \u3002<\/p>\n\n\n\n
      \u4e09\u3001\u96c6\u6210\u5230 ReverseProxy<\/h3>\n\n\n\n
      \u73b0\u5728\u4fee\u6539 ReverseProxy \u51fd\u6570\uff0c\u8ba9\u5b83\u4e0d\u518d\u63a5\u6536\u5355\u4e2a target \uff0c\u800c\u662f\u63a5\u6536\u4e00\u4e2a\u8d1f\u8f7d\u5747\u8861\u5668\u5b9e\u4f8b\uff0c\u5e76\u6839\u636e\u7b56\u7565\u9009\u62e9\u540e\u7aef\u3002<\/p>\n\n\n\n
      func ReverseProxy(lb *LoadBalancer, strategy string) http.HandlerFunc {\n\treturn func(w http.ResponseWriter, r *http.Request) {\n\t\t\/\/ 1. \u6839\u636e\u7b56\u7565\u9009\u62e9\u540e\u7aef\n\t\tvar backend *Backend\n\t\tswitch strategy{\n\t\tcase \"round-robin\":\n\t\t\tbackend = lb.NextRoundRobin()\n\t\tcase \"random\":\n\t\t\tbackend = lb.NextRandom()\n\t\tcase \"least-conn\":\n\t\t\tbackend = lb.NextLeastConnections()\n\t\tcase \"ip-hash\":\n\t\t\tip, _, _ := net.SplitHostPort(r.RemoteAddr)\n\t\t\tbackend = lb.NextIPHash(ip)\n\t\tdefault:\n\t\t\thttp.Error(w, \"unknown strategy\", http.StatusInternalServerError)\n\t\t\treturn\n\t\t}\n\n\t\tif backend == nil {\n\t\t\thttp.Error(w, \"no available backend\", http.StatusServiceUnavailable)\n\t\t\treturn\n\t\t}\n\n\t\t\/\/ 2. \u589e\u52a0\u8fde\u63a5\u6570\uff08\u7528\u4e8e\u6700\u5c11\u8fde\u63a5\u6570\u7b56\u7565\uff09\n\t\tatomic.AddInt64(&backend.Connections, 1)\n\t\t\/\/ \u5728\u51fd\u6570\u8fd4\u56de\u524d\u51cf\u5c11\u8fde\u63a5\u6570\n\t\tdefer atomic.AddInt64(&backend.Connections, -1)\n\n\t\t\/\/ 3. \u6784\u5efa\u8f6c\u53d1\u8bf7\u6c42\uff08\u4e0e\u4e4b\u524d\u76f8\u540c\uff0c\u4f46 target \u6362\u6210 backend.URL)\n\t\tproxyURL := backend.URL.ResolveReference(r.URL)\n\t\treq, err := http.NewRequest(r.Method, proxyURL.String(), r.Body)\n\t\tif err != nil{\n\t\t\thttp.Error(w, err.Error(), http.StatusInternalServerError)\n\t\t\treturn\n\t\t}\n\n\t\treq.Header = r.Header.Clone()\n\t\treq.Host = backend.URL.Host\n\n\t\t\/\/ 4. \u53d1\u9001\u8bf7\u6c42\n\t\tclient := http.DefaultClient\n\t\tresp, err := client.Do(req)\n\t\tif err != nil {\n\t\t\thttp.Error(w, err.Error(), http.StatusBadGateway)\n\t\t\treturn\n\t\t}\n\t\tdefer resp.Body.Close()\n\n\t\t\/\/ 5. \u5199\u56de\u54cd\u5e94\uff08\u6ce8\u610f\u987a\u5e8f\uff1a\u5148 Header\uff0c\u518d WriteHeader)\n\t\tfor key, values := range resp.Header{\n\t\t\tfor _, value := range values{\n\t\t\t\tw.Header().Add(key, value)\n\t\t\t}\n\t\t}\n\t\tw.WriteHeader(resp.StatusCode)\n\t\tio.Copy(w, resp.Body)\n\t}\n}<\/code><\/pre>\n\n\n\n
      \u56db\u3001\u5e76\u53d1\u5b89\u5168\u95ee\u9898\u8ba8\u8bba<\/h3>\n\n\n\n
      \u8fd9\u91cc\u7684 lb.mu \u8bfb\u5199\u9501\u4e3b\u8981\u4fdd\u62a4 backends \u5207\u7247\u672c\u8eab\uff0c\u9632\u6b62\u5728\u904d\u5386\u65f6\u5207\u7247\u88ab\u4fee\u6539\uff08\u6bd4\u5982\u5065\u5eb7\u68c0\u67e5\u52a8\u6001\u79fb\u9664\u540e\u7aef\uff09\u3002\u76ee\u524d\u6211\u4eec\u8fd8\u6ca1\u5b9e\u73b0\u52a8\u6001\u66f4\u65b0\uff0c\u4f46\u5148\u52a0\u4e0a\uff0c\u4e3a\u540e\u7eed\u51c6\u5907\u3002<\/p>\n\n\n\n
      \u4e94\u3001\u5b8c\u6574\u793a\u4f8b\u4ee3\u7801<\/h3>\n\n\n\n
      \u4e3a\u4e86\u65b9\u4fbf\u6d4b\u8bd5\uff0c\u53ef\u4ee5\u5728 main \u51fd\u6570\u4e2d\u521b\u5efa\u51e0\u4e2a\u6d4b\u8bd5\u540e\u7aef\u5730\u5740\uff0c\u7136\u540e\u542f\u52a8\u4ee3\u7406\u3002<\/p>\n\n\n\n
      \u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n\n\n\n
      package main\n\nimport (\n\t\"hash\/fnv\"\n\t\"io\"\n\t\"log\"\n\t\"math\/rand\"\n\t\"net\"\n\t\"net\/http\"\n\t\"net\/url\"\n\t\"sync\"\n\t\"sync\/atomic\"\n\t\"time\"\n)\n\ntype Backend struct{\n\tURL *url.URL\n\tAlive bool \/\/ \u662f\u5426\u5b58\u6d3b\uff08\u5065\u5eb7\u68c0\u67e5\u7528\uff09\n\tConnections int64 \/\/ \u5f53\u524d\u6d3b\u8dc3\u8fde\u63a5\u6570\uff08\u539f\u5b50\u64cd\u4f5c\uff09\n}\n\ntype LoadBalancer struct{\n\tbackends []*Backend\n\tcurrent uint64 \/\/ \u8f6e\u8be2\u7528\uff0c\u6307\u5411\u4e0b\u4e00\u4e2a\u8981\u9009\u62e9\u7684\u540e\u7aef\u7d22\u5f15\n\tmu sync.RWMutex \/\/ \u4fdd\u62a4 backends \u5207\u7247\uff08\u6bd4\u5982\u52a8\u6001\u589e\u5220\u540e\u7aef\uff09\n}\n\n\/\/ \u521d\u59cb\u5316\nfunc NewLoadBalancer(urls []string) *LoadBalancer{\n\tvar backends []*Backend\n\tfor _, u := range urls{\n\t\tparsed, _ := url.Parse(u)\n\t\tbackends = append(backends, &Backend{\n\t\t\tURL: parsed,\n\t\t\tAlive: true,\n\t\t\tConnections: 0,\n\t\t})\n\t}\n\treturn &LoadBalancer{\n\t\tbackends: backends,\n\t\tcurrent: 0,\n\t}\n}\n\n\/\/ \u5b9e\u73b0\u8d1f\u8f7d\u5747\u8861\u7b97\u6cd5\n\n\/\/ 1. \u8f6e\u8be2\nfunc (lb *LoadBalancer) NextRoundRobin() *Backend {\n\tlb.mu.RLock() \/\/ \u52a0\u8bfb\u9501\uff0c\u7981\u6b62\u5176\u4ed6 goroutine \u4fee\u6539 backends\n    defer lb.mu.RUnlock()\n\t\/\/ \u6ce8\u610f\u5230\uff1a\u4e00\u81f4\u6027\u54c8\u5e0c\u53ef\u4ee5\u907f\u514d\u8d8a\u754c\u95ee\u9898\uff0c\u540e\u7eed\u8fdb\u884c\u5b66\u4e60\n\n\tn := uint64(len(lb.backends))\n\tif n == 0{\n\t\treturn nil\n\t}\n\n\t\/\/ \u539f\u5b50\u5730\u589e\u52a0 current \uff0c\u5e76\u53d6\u6a21\n\tnext := atomic.AddUint64(&lb.current, 1) % n\n\n\treturn lb.backends[next]\n}\n\n\/\/ 2. \u968f\u673a\nvar rngMu sync.Mutex\nfunc (lb *LoadBalancer) NextRandom() *Backend {\n\tlb.mu.RLock()\n\tdefer lb.mu.RUnlock()\n\n\tn := len(lb.backends)\n\tif n == 0{\n\t\treturn nil\n\t}\n\n\trngMu.Lock()\n\tidx := rand.Intn(n)\n\trngMu.Unlock()\n\n\t\/\/ \u66f4\u597d\u7684\u505a\u6cd5\uff1a\u4f7f\u7528 rand.New(rand.NewSource(time.Now().UnixNano())) \n\t\/\/ \u521b\u5efa\u4e00\u4e2a\u79c1\u6709\u7684\u968f\u673a\u6e90\uff0c\u5e76\u7528\u4e00\u4e2a sync.Mutex \u4fdd\u62a4\u5b83\n\n\treturn lb.backends[idx]\n}\n\n\/\/ 3. \u6700\u5c11\u8fde\u63a5\u6570\nfunc (lb *LoadBalancer) NextLeastConnections() *Backend {\n\tlb.mu.RLock()\n\tdefer lb.mu.RUnlock()\n\n\tvar selected *Backend\n\tvar minConns int64 = 1<<63 - 1\n\n\tfor _, b := range lb.backends {\n\t\tif !b.Alive {\n\t\t\tcontinue\n\t\t}\n\n\t\tconns := atomic.LoadInt64(&b.Connections)\n\t\tif conns < minConns {\n\t\t\tminConns = conns\n\t\t\tselected = b\n\t\t}\n\t}\n\n\treturn selected\n}\n\n\/\/ 4. IP Hash\nfunc (lb *LoadBalancer) NextIPHash(ip string) *Backend {\n\tlb.mu.RLock()\n\tdefer lb.mu.RUnlock()\n\n\n\n\tn := len(lb.backends)\n\tif n == 0 {\n\t\treturn nil\n\t}\n\n\t\/\/ \u7b80\u5355\u7684\u54c8\u5e0c\uff1a\u628a IP \u5b57\u7b26\u4e32\u8f6c\u6210\u6574\u6570\u7136\u540e\u53d6\u6a21\n\th := fnv.New32a()\n\th.Write([]byte(ip))\n\thash := h.Sum32()\n\tidx := int(hash) % n\n\treturn lb.backends[idx]\n}\n\nfunc ReverseProxy(lb *LoadBalancer, strategy string) http.HandlerFunc {\n\treturn func(w http.ResponseWriter, r *http.Request) {\n\t\t\/\/ 1. \u6839\u636e\u7b56\u7565\u9009\u62e9\u540e\u7aef\n\t\tvar backend *Backend\n\t\tswitch strategy{\n\t\tcase \"round-robin\":\n\t\t\tbackend = lb.NextRoundRobin()\n\t\tcase \"random\":\n\t\t\tbackend = lb.NextRandom()\n\t\tcase \"least-conn\":\n\t\t\tbackend = lb.NextLeastConnections()\n\t\tcase \"ip-hash\":\n\t\t\tip, _, _ := net.SplitHostPort(r.RemoteAddr)\n\t\t\tbackend = lb.NextIPHash(ip)\n\t\tdefault:\n\t\t\thttp.Error(w, \"unknown strategy\", http.StatusInternalServerError)\n\t\t\treturn\n\t\t}\n\n\t\tif backend == nil {\n\t\t\thttp.Error(w, \"no available backend\", http.StatusServiceUnavailable)\n\t\t\treturn\n\t\t}\n\n\t\t\/\/ 2. \u589e\u52a0\u8fde\u63a5\u6570\uff08\u7528\u4e8e\u6700\u5c11\u8fde\u63a5\u6570\u7b56\u7565\uff09\n\t\tatomic.AddInt64(&backend.Connections, 1)\n\t\t\/\/ \u5728\u51fd\u6570\u8fd4\u56de\u524d\u51cf\u5c11\u8fde\u63a5\u6570\n\t\tdefer atomic.AddInt64(&backend.Connections, -1)\n\n\t\t\/\/ 3. \u6784\u5efa\u8f6c\u53d1\u8bf7\u6c42\uff08\u4e0e\u4e4b\u524d\u76f8\u540c\uff0c\u4f46 target \u6362\u6210 backend.URL)\n\t\tproxyURL := backend.URL.ResolveReference(r.URL)\n\t\treq, err := http.NewRequest(r.Method, proxyURL.String(), r.Body)\n\t\tif err != nil{\n\t\t\thttp.Error(w, err.Error(), http.StatusInternalServerError)\n\t\t\treturn\n\t\t}\n\n\t\treq.Header = r.Header.Clone()\n\t\treq.Host = backend.URL.Host\n\n\t\t\/\/ 4. \u53d1\u9001\u8bf7\u6c42\n\t\tclient := http.DefaultClient\n\t\tresp, err := client.Do(req)\n\t\tif err != nil {\n\t\t\thttp.Error(w, err.Error(), http.StatusBadGateway)\n\t\t\treturn\n\t\t}\n\t\tdefer resp.Body.Close()\n\n\t\t\/\/ 5. \u5199\u56de\u54cd\u5e94\uff08\u6ce8\u610f\u987a\u5e8f\uff1a\u5148 Header\uff0c\u518d WriteHeader)\n\t\tfor key, values := range resp.Header{\n\t\t\tfor _, value := range values{\n\t\t\t\tw.Header().Add(key, value)\n\t\t\t}\n\t\t}\n\t\tw.WriteHeader(resp.StatusCode)\n\t\tio.Copy(w, resp.Body)\n\t}\n}\n\nfunc main() {\n\tbackendURLs := []string {\n\t\t\"http:\/\/127.0.0.1:8001\",\n        \"http:\/\/127.0.0.1:8002\",\n        \"http:\/\/127.0.0.1:8003\",\n\t}\n\tlb := NewLoadBalancer(backendURLs)\n\n\tstrategy := \"round-robin\"\n\n\thttp.HandleFunc(\"\/\", ReverseProxy(lb, strategy))\n\n\tlog.Println(\"Starting proxy server on :8080\")\n\tlog.Fatal(http.ListenAndServe(\":8080\", nil))\n}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
      \u56de\u987e\u4e0e\u76ee\u6807\uff1a \u5728\u4e4b\u524d\u7684\u5b9e\u73b0\u4e2d\uff0c ReverseProxy \u51fd\u6570\u63a5\u6536\u4e00\u4e2a\u56fa\u5b9a\u7684 target *url.URL  … \u9605\u8bfb\u66f4\u591a<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-19","post","type-post","status-publish","format-standard","hentry","category-golangproxy"],"_links":{"self":[{"href":"https:\/\/fableary.top\/index.php?rest_route=\/wp\/v2\/posts\/19","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fableary.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fableary.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fableary.top\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/fableary.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=19"}],"version-history":[{"count":2,"href":"https:\/\/fableary.top\/index.php?rest_route=\/wp\/v2\/posts\/19\/revisions"}],"predecessor-version":[{"id":23,"href":"https:\/\/fableary.top\/index.php?rest_route=\/wp\/v2\/posts\/19\/revisions\/23"}],"wp:attachment":[{"href":"https:\/\/fableary.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=19"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fableary.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=19"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fableary.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=19"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}