{"record":{"id":"af896ba67ba472f3","repo":"hyperledger/fabric","slug":"error-marshaling-computed-config-update","errorCode":null,"errorMessage":"error marshaling computed config update","messagePattern":"error marshaling computed config update","errorType":"console","errorClass":null,"httpStatus":null,"severity":"error","filePath":"cmd/configtxlator/main.go","lineNumber":225,"sourceCode":"\t\treturn errors.Wrapf(err, \"error reading updated config\")\n\t}\n\n\tupdtConf := &cb.Config{}\n\terr = proto.Unmarshal(updtIn, updtConf)\n\tif err != nil {\n\t\treturn errors.Wrapf(err, \"error unmarshalling updated config\")\n\t}\n\n\tcu, err := update.Compute(origConf, updtConf)\n\tif err != nil {\n\t\treturn errors.Wrapf(err, \"error computing config update\")\n\t}\n\n\tcu.ChannelId = channelID\n\n\toutBytes, err := proto.Marshal(cu)\n\tif err != nil {\n\t\treturn errors.Wrapf(err, \"error marshaling computed config update\")\n\t}\n\n\t_, err = output.Write(outBytes)\n\tif err != nil {\n\t\treturn errors.Wrapf(err, \"error writing config update to output\")\n\t}\n\n\treturn nil\n}\n","sourceCodeStart":207,"sourceCodeEnd":235,"githubUrl":"https://github.com/hyperledger/fabric/blob/2736b63f8fd5932511d56fe68b7039d15977f7f6/cmd/configtxlator/main.go#L207-L235","documentation":"computeUpdt in the configtxlator tool marshals the computed protobuf ConfigUpdate to bytes before writing to the output file. If proto.Marshal fails on the ConfigUpdate, this wrapped error is returned and configtxlator output computation aborts. proto.Marshal should rarely fail unless the message contains unmarshalable state (e.g. required proto2 fields unset, or nil message with required fields).","triggerScenarios":"Running 'configtxlator compute-update' where the generated ConfigUpdate protobuf cannot be marshaled — typically a nil or malformed ConfigUpdate, or corrupted intermediate config data produced by mismatched input config blocks.","commonSituations":"Feeding config blocks from different channels into configtxlator; corrupted or truncated config block protobufs; custom/modified config proto extensions that are invalid; using output from an earlier failed decode step.","solutions":["Verify both input config blocks are from the same channel and valid protobufs (decode them with configtxlator decode first).","Check the wrapped inner error in the log to identify which field failed marshaling.","Re-export the config blocks from a live orderer (fetch config block) instead of reusing cached files.","Rebuild configtxlator to match your fabric protos version."],"exampleFix":"null","handlingStrategy":"validation","validationCode":"// validate inputs before compute-update\nfor _, f := range []string{originalPath, updatedPath} {\n    b, err := os.ReadFile(f)\n    if err != nil { log.Fatalf(\"cannot read %s: %v\", f, err) }\n    var cb common.Config\n    if err := proto.Unmarshal(b, &cb); err != nil {\n        log.Fatalf(\"%s is not a valid protobuf Config: %v\", f, err)\n    }\n}","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Decode both input blocks with 'configtxlator decode' to prove they are valid Configs","Ensure both inputs come from the same channel","Regenerate inputs from a live orderer rather than reusing stale files","Match configtxlator version to your fabric network version"],"tags":["configtxlator","protobuf","serialization"],"backgroundTag":"protobuf-marshal-failed","analyzedSha":"2736b63f8fd5932511d56fe68b7039d15977f7f6","analyzedAt":"2026-09-04T08:52:36.465Z","contentChangedAt":"2026-09-04T08:52:36.465Z","schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}