{"record":{"id":"4e658e79f7e54abc","repo":"kubernetes/kops","slug":"error-reading-response-for-q-v","errorCode":null,"errorMessage":"error reading response for %q: %v","messagePattern":"error reading response for %q: (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"util/pkg/vfs/context.go","lineNumber":272,"sourceCode":"\tdone, err := RetryWithBackoff(opts.backoff, func() (bool, error) {\n\t\tklog.V(4).Infof(\"Performing HTTP request: GET %s\", httpURL)\n\t\treq, err := http.NewRequest(\"GET\", httpURL, nil)\n\t\tif err != nil {\n\t\t\treturn false, err\n\t\t}\n\t\tfor k, v := range httpHeaders {\n\t\t\treq.Header.Add(k, v)\n\t\t}\n\t\tresponse, err := http.DefaultClient.Do(req)\n\t\tif response != nil {\n\t\t\tdefer response.Body.Close()\n\t\t}\n\t\tif err != nil {\n\t\t\treturn false, fmt.Errorf(\"error fetching %q: %v\", httpURL, err)\n\t\t}\n\t\tbody, err = io.ReadAll(response.Body)\n\t\tif err != nil {\n\t\t\treturn false, fmt.Errorf(\"error reading response for %q: %v\", httpURL, err)\n\t\t}\n\t\tif response.StatusCode == 404 {\n\t\t\t// We retry on 404s in case of eventual consistency\n\t\t\treturn false, os.ErrNotExist\n\t\t}\n\t\tif response.StatusCode >= 500 && response.StatusCode <= 599 {\n\t\t\t// Retry on 5XX errors\n\t\t\treturn false, fmt.Errorf(\"unexpected response code %q for %q: %v\", response.Status, httpURL, string(body))\n\t\t}\n\n\t\tif response.StatusCode == 200 {\n\t\t\treturn true, nil\n\t\t}\n\n\t\t// Don't retry on other errors\n\t\treturn true, fmt.Errorf(\"unexpected response code %q for %q: %v\", response.Status, httpURL, string(body))\n\t})\n\tif err != nil {","sourceCodeStart":254,"sourceCodeEnd":290,"githubUrl":"https://github.com/kubernetes/kops/blob/4c8573c808a73d578c5eadc86d410646ea0b0d73/util/pkg/vfs/context.go#L254-L290","documentation":"After a successful HTTP response, readHTTPLocation reads the body with io.ReadAll. If reading the body fails mid-stream (connection reset, unexpected EOF, chunked-encoding break) the error is wrapped as 'error reading response for <url>'. Like the fetch error, this is a retryable condition inside the backoff loop.","triggerScenarios":"ReadFile over http(s) where the TCP connection drops while the body is being read, a proxy/LB truncates the response, or the server closes the connection before finishing the chunked body.","commonSituations":"Unstable networks or VPN drops mid-transfer; load balancers with short idle timeouts killing large downloads; misbehaving proxies stripping/truncating chunked responses.","solutions":["Simply retry - the built-in exponential backoff (5 steps) usually rides out transient resets","Check for proxy/LB idle timeout limits and raise them for the target URL","Test with `curl -v --raw <url>` to reproduce truncation and identify the terminating hop","Provide the file over a more reliable host/CDN if the server repeatedly resets"],"exampleFix":"// before\nwait.Backoff{Duration: 500 * time.Millisecond, Factor: 2, Steps: 5} // may exhaust on flaky links\n// after\nvfs.WithBackoff(wait.Backoff{Duration: time.Second, Factor: 2, Steps: 10, Cap: 30 * time.Second})","handlingStrategy":"retry","validationCode":"// no pre-call validation exists for mid-body truncation; rely on retries and integrity checks\nfunc bodyReadSafe(loc string) error { return nil }","typeGuard":null,"tryCatchPattern":"err := wait.ExponentialBackoff(wait.Backoff{Duration: time.Second, Factor: 2, Steps: 6}, func() (bool, error) {\n\t_, err := vfs.Context.ReadFile(loc)\n\tif err != nil && strings.Contains(err.Error(), \"error reading response\") {\n\t\treturn false, nil // truncated body - retry\n\t}\n\treturn err == nil, err\n})","preventionTips":["Serve large files from hosts/CDNs with generous idle timeouts","Avoid flaky links/proxies; investigate repeated unexpected-EOF errors at the LB","Validate downloaded content (hash/parse) after ReadFile so truncation is caught"],"tags":["network","http","io"],"backgroundTag":"http-body-read-error","analyzedSha":"4c8573c808a73d578c5eadc86d410646ea0b0d73","analyzedAt":"2026-09-05T04:13:19.212Z","contentChangedAt":"2026-09-05T04:13:19.212Z","schemaVersion":2},"datasetVersion":"2026-09-12T07:17:12.445Z"}