{"record":{"id":"f2b19d58a015a5c6","repo":"JuliusBrussee/caveman","slug":"cachebench-trace-line-d-invalid-prefix","errorCode":null,"errorMessage":"cachebench: trace line %d: invalid prefix","messagePattern":"cachebench: trace line (.+?): invalid prefix","errorType":"validation","errorClass":null,"httpStatus":null,"severity":"error","filePath":"cacheengine/cachebench/trace.go","lineNumber":322,"sourceCode":"\t\tvar record TraceRecord\n\t\tif err := decoder.Decode(&record); err != nil {\n\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: %w\", line, err)\n\t\t}\n\t\tvar trailing any\n\t\tif err := decoder.Decode(&trailing); err != io.EOF {\n\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: trailing JSON\", line)\n\t\t}\n\t\tif record.Schema != TraceSchema && record.Schema != TraceSchemaV2 && record.Schema != TraceSchemaV1 || !validBoundedText(record.RequestID, 512, false) || seen[record.RequestID] {\n\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: invalid schema or request_id\", line)\n\t\t}\n\t\tif _, err := time.Parse(time.RFC3339Nano, record.At); err != nil || !validTraceIdentity(record) || record.PrefixTokens < 0 {\n\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: incomplete request identity\", line)\n\t\t}\n\t\tif len(record.Body) > limits.MaxBodyBytes || !json.Valid(record.Body) || record.BodySHA256 == \"\" || record.BodySHA256 != bodyDigest(record.Body) {\n\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: invalid body or digest\", line)\n\t\t}\n\t\tif record.StableSegmentCount < 0 || record.StableSegmentCount > len(record.Prefix) || !validPrefix(record.Prefix) {\n\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: invalid prefix\", line)\n\t\t}\n\t\tif record.Schema == TraceSchema || record.Schema == TraceSchemaV2 {\n\t\t\tif record.ExpectedRPM <= 0 || record.ExpectedCalls <= 0 || !validTimingBasis(record.TimingBasis) {\n\t\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: incomplete replay metadata\", line)\n\t\t\t}\n\t\t}\n\t\tif record.Schema == TraceSchema {\n\t\t\tif record.DeclaredInputTokens <= 0 || record.DeclaredInputTokens < record.PrefixTokens || record.MaxOutputTokens <= 0 || !requestBudgetMatchesBody(record) {\n\t\t\t\treturn nil, fmt.Errorf(\"cachebench: trace line %d: incomplete or mismatched billed-token budget\", line)\n\t\t\t}\n\t\t}\n\t\tseen[record.RequestID] = true\n\t\trecord.Body = append(json.RawMessage(nil), record.Body...)\n\t\trecords = append(records, record)\n\t}\n\tif err := scanner.Err(); err != nil {\n\t\treturn nil, fmt.Errorf(\"cachebench: read trace: %w\", err)\n\t}","sourceCodeStart":304,"sourceCodeEnd":340,"githubUrl":"https://github.com/JuliusBrussee/caveman/blob/27d5a3981a347890211bb1bf2439e5c821a63bc9/cacheengine/cachebench/trace.go#L304-L340","documentation":"Error \"cachebench: trace line %d: invalid prefix\" thrown in JuliusBrussee/caveman.","triggerScenarios":"Thrown at cacheengine/cachebench/trace.go:322 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Fix the prefix on the trace line."],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"27d5a3981a347890211bb1bf2439e5c821a63bc9","analyzedAt":"2026-08-15T09:26:11.751Z","schemaVersion":2},"datasetVersion":"2026-08-15T17:31:12.345Z"}