{"record":{"id":"6ec4fe50b41a4e2f","repo":"jeessy2/ddns-go","slug":"could-not-download-release-from-s-v","errorCode":null,"errorMessage":"could not download release from %s: %v","messagePattern":"could not download release from (.+?): (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"util/update/package.go","lineNumber":68,"sourceCode":"\n// to 从 assetURL 下载可执行文件，并用下载的文件替换当前的可执行文件。\n// 这个函数是用于更新二进制文件的低级 API。因为它不使用源提供者，而是直接通过 HTTP 从 URL 下载 asset 。\n// 所以这个函数不能用于更新私有仓库的 release。\n// cmdPath 是命令可执行文件的文件路径。\nfunc to(assetURL, assetFileName, cmdPath string) error {\n\tsrc, err := downloadAssetFromURL(assetURL)\n\tif err != nil {\n\t\treturn err\n\t}\n\tdefer src.Close()\n\treturn decompressAndUpdate(src, assetFileName, cmdPath)\n}\n\nfunc downloadAssetFromURL(url string) (rc io.ReadCloser, err error) {\n\tclient := util.CreateHTTPClient()\n\tresp, err := client.Get(url)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"could not download release from %s: %v\", url, err)\n\t}\n\tif resp.StatusCode >= 300 {\n\t\tresp.Body.Close()\n\t\treturn nil, fmt.Errorf(\"could not download release from %s. Response code: %d\", url, resp.StatusCode)\n\t}\n\n\treturn resp.Body, nil\n}\n","sourceCodeStart":50,"sourceCodeEnd":77,"githubUrl":"https://github.com/jeessy2/ddns-go/blob/5874c2e6667c69357ab95079421131104bd3fcae/util/update/package.go#L50-L77","documentation":"downloadAssetFromURL in util/update/package.go performs client.Get(url) with the shared HTTP client; if the transport-level request itself fails, it wraps the cause with the URL using %v. This means DNS failure, connection refused/timeout, TLS errors, or context cancellation prevented even receiving an HTTP response.","triggerScenarios":"client.Get(url) returns a non-nil err — no HTTP status was obtained. Raised from downloadAssetFromURL and propagated to its caller to() during the update download step.","commonSituations":"Offline machine or broken DNS; firewall/proxy blocking the release host (e.g. github.com); wrong release URL configured; TLS certificate problems; request deadline exceeded on slow networks.","solutions":["Check network connectivity and DNS for the release host (curl -I <url>).","Inspect the wrapped %v cause to identify DNS vs connection vs TLS failure and fix accordingly (proxy env HTTPS_PROXY, VPN, /etc/hosts).","Correct the release asset URL in the update configuration if it points to a nonexistent host.","Add retry with backoff around downloadAssetFromURL for transient network errors."],"exampleFix":"// before\nrc, err := to(assetURL)\n// after\nvar rc io.ReadCloser\nfor i := 0; i < 3 && rc == nil; i++ {\n\trc, err = to(assetURL)\n\tif err != nil {\n\t\ttime.Sleep(time.Duration(1<<i) * time.Second)\n\t}\n}","handlingStrategy":"retry","validationCode":"// before calling the updater\nurlObj, err := neturl.Parse(assetURL)\nif err != nil || urlObj.Scheme != \"https\" {\n\treturn fmt.Errorf(\"invalid asset URL: %s\", assetURL)\n}\n// connectivity precheck\nresp, err := http.Head(assetURL)\nif err != nil {\n\treturn fmt.Errorf(\"release host unreachable: %v\", err)\n}","typeGuard":null,"tryCatchPattern":"var lastErr error\nfor attempt := 0; attempt < 3; attempt++ {\n\trc, err := downloadAssetFromURL(url)\n\tif err == nil { return rc, nil }\n\tlastErr = err\n\ttime.Sleep(time.Duration(1<<attempt) * time.Second)\n}\nreturn nil, fmt.Errorf(\"download failed after retries: %w\", lastErr)","preventionTips":["Check connectivity/DNS and proxy settings (HTTPS_PROXY) before running updates.","Use retries with exponential backoff for transient network failures.","Validate the release URL configuration points at a reachable host.","Set reasonable client timeouts so failures surface fast and clearly."],"tags":["go","network","http","updater"],"backgroundTag":"http-request-failed","analyzedSha":"5874c2e6667c69357ab95079421131104bd3fcae","analyzedAt":"2026-09-03T15:41:16.799Z","contentChangedAt":"2026-09-03T15:41:16.799Z","schemaVersion":2},"datasetVersion":"2026-09-11T00:17:11.886Z"}