{"record":{"id":"0daa4e89234165fe","repo":"flipped-aurora/gin-vue-admin","slug":"w-0daa4e","errorCode":null,"errorMessage":"请求上游接口失败: %w","messagePattern":"请求上游接口失败: %w","errorType":"http","errorClass":null,"httpStatus":null,"severity":"error","filePath":"server/mcp/http_client.go","lineNumber":120,"sourceCode":"\n// defaultUpstreamTimeout 是回打主服务公共(免鉴权)接口的默认超时。\nconst defaultUpstreamTimeout = 10 * time.Second\n\n// fetchPublicUpstream 回打主服务的公共(免鉴权)接口:带超时的 GET + 标准信封解析。\n// 动态 tool 与编排 prompt 的注册共用同一模式,T 为信封 Data 字段的具体负载类型。\nfunc fetchPublicUpstream[T any](path string) (*upstreamEnvelope[T], error) {\n\ttimeoutCtx, cancel := context.WithTimeout(context.Background(), defaultUpstreamTimeout)\n\tdefer cancel()\n\n\treq, err := http.NewRequestWithContext(timeoutCtx, http.MethodGet, upstreamURL(path), nil)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"构建请求失败: %w\", err)\n\t}\n\treq.Header.Set(\"Accept\", \"application/json\")\n\n\tresp, err := http.DefaultClient.Do(req)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"请求上游接口失败: %w\", err)\n\t}\n\tdefer resp.Body.Close()\n\n\trawBody, err := io.ReadAll(resp.Body)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"读取响应失败: %w\", err)\n\t}\n\tif resp.StatusCode >= http.StatusBadRequest {\n\t\treturn nil, fmt.Errorf(\"上游接口返回状态码 %d: %s\", resp.StatusCode, string(rawBody))\n\t}\n\n\tvar result upstreamEnvelope[T]\n\tif err := json.Unmarshal(rawBody, &result); err != nil {\n\t\treturn nil, fmt.Errorf(\"解析响应失败: %w\", err)\n\t}\n\tif result.Code != 0 {\n\t\treturn nil, fmt.Errorf(\"上游接口业务错误: %s\", result.Msg)\n\t}","sourceCodeStart":102,"sourceCodeEnd":138,"githubUrl":"https://github.com/flipped-aurora/gin-vue-admin/blob/3136500ef380842b0eb6c4daa87c3f8a47fcf9e0/server/mcp/http_client.go#L102-L138","documentation":"The same helper fails with this error when http.DefaultClient.Do returns an error: DNS resolution failure, connection refused/reset, TLS errors, or the context deadline (defaultUpstreamTimeout) expiring before the response arrives.","triggerScenarios":"GET to the public upstream endpoint fails at transport level: upstream down, wrong host/port, firewall, DNS outage, or slow upstream exceeding defaultUpstreamTimeout.","commonSituations":"Upstream service not running during local dev; network egress blocked in CI/container; typo in upstream hostname; upstream latency spike triggering the timeout; TLS cert expired on the upstream.","solutions":["Check the wrapped error message for root cause (dial tcp: connection refused / no such host / context deadline exceeded)","Verify the upstream service is reachable: curl the same URL from the server host","If timeouts are the cause, review defaultUpstreamTimeout and upstream load","Check DNS/egress rules (proxy env, firewall) in the deployment environment"],"exampleFix":"// before\nresp, err := http.DefaultClient.Do(req) // context deadline exceeded\n// after\nclient := &http.Client{Timeout: 30 * time.Second} // and ensure upstream is reachable\nresp, err := client.Do(req)","handlingStrategy":"retry","validationCode":"// pre-check reachability before invoking the tool\nconn, err := net.DialTimeout(\"tcp\", host, 3*time.Second)\nif err != nil { return fmt.Errorf(\"upstream unreachable: %w\", err) }\nconn.Close()","typeGuard":"func isTimeoutErr(err error) bool { return errors.Is(err, context.DeadlineExceeded) || errors.Is(err, os.ErrDeadlineExceeded) }","tryCatchPattern":"resp, err := client.Do(req)\nif err != nil {\n  if isTimeoutErr(err) {\n    return nil, fmt.Errorf(\"upstream timeout, retry later: %w\", err)\n  }\n  return nil, fmt.Errorf(\"upstream request failed: %w\", err)\n}\ndefer resp.Body.Close()","preventionTips":["Retry transient transport errors with backoff (respecting the request context)","Confirm upstream health (curl / health endpoint) before tool calls","Set a realistic defaultUpstreamTimeout for upstream latency","Verify DNS/proxy/egress config in containers and CI"],"tags":["network","http","upstream","timeout"],"backgroundTag":"connection-refused","analyzedSha":"3136500ef380842b0eb6c4daa87c3f8a47fcf9e0","analyzedAt":"2026-08-31T13:50:02.721Z","schemaVersion":2},"datasetVersion":"2026-08-31T19:17:28.585Z"}