{"record":{"id":"ce1f1dd97a88c47c","repo":"hyperledger/fabric","slug":"unmarshalling-block-s","errorCode":null,"errorMessage":"unmarshalling block: %s","messagePattern":"unmarshalling block: (.+?)","errorType":"console","errorClass":null,"httpStatus":null,"severity":"error","filePath":"cmd/osnadmin/main.go","lineNumber":214,"sourceCode":"func readBodyBytes(body io.ReadCloser) ([]byte, error) {\n\tbodyBytes, err := io.ReadAll(body)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"reading http response body: %s\", err)\n\t}\n\tbody.Close()\n\n\treturn bodyBytes, nil\n}\n\nfunc errorOutput(err error) string {\n\treturn fmt.Sprintf(\"Error: %s\\n\", err)\n}\n\nfunc validateBlockChannelID(blockBytes []byte, channelID string) error {\n\tblock := &common.Block{}\n\terr := proto.Unmarshal(blockBytes, block)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"unmarshalling block: %s\", err)\n\t}\n\n\tblockChannelID, err := protoutil.GetChannelIDFromBlock(block)\n\tif err != nil {\n\t\treturn err\n\t}\n\n\t// quick sanity check that the orderer admin is joining\n\t// the channel they think they're joining.\n\tif channelID != blockChannelID {\n\t\treturn fmt.Errorf(\"specified --channelID %s does not match channel ID %s in config block\", channelID, blockChannelID)\n\t}\n\n\treturn nil\n}\n\nfunc validateEnvelopeChannelID(envelopeBytes []byte, channelID string) error {\n\tenvelope := &common.Envelope{}","sourceCodeStart":196,"sourceCodeEnd":232,"githubUrl":"https://github.com/hyperledger/fabric/blob/2736b63f8fd5932511d56fe68b7039d15977f7f6/cmd/osnadmin/main.go#L196-L232","documentation":"validateBlockChannelID unmarshals the --configBlock bytes into common.Block with proto.Unmarshal; any parse failure is wrapped as this error. It means the file is not a valid protobuf-encoded fabric block.","triggerScenarios":"Passing a text/gzip file, an envelope instead of a block, a truncated or corrupted block, or an empty file as --configBlock.","commonSituations":"Using an old serialized block from an incompatible fabric version, transferring the file with corruption (e.g. wrong binary mode), or mixing up the config update envelope with the config block.","solutions":["Verify the file is a binary protobuf block (e.g. produced by `peer channel fetch config` or `configtxgen -outputBlock`).","Re-fetch or regenerate the config block.","Ensure the file was not corrupted or truncated in transfer.","Confirm you passed the block to --configBlock, not the envelope."],"exampleFix":"// before\nosnadmin channel join --channelID mychannel --configBlock config_update_envelope.pb\n// after\nosnadmin channel join --channelID mychannel --configBlock mychannel.block","handlingStrategy":"validation","validationCode":"func looksLikeBlock(b []byte) bool {\n    block := &common.Block{}\n    return proto.Unmarshal(b, block) == nil\n}\n// run before invoking osnadmin join","typeGuard":"func isProtoBlock(b []byte) bool {\n    blk := &common.Block{}\n    if proto.Unmarshal(b, blk) != nil { return false }\n    return blk.Header != nil && blk.Data != nil\n}","tryCatchPattern":"if err := runOsnadmin(); err != nil {\n    if strings.Contains(err.Error(), \"unmarshalling block:\") {\n        log.Fatalf(\"--configBlock is not a valid protobuf block: %v\", err)\n    }\n}","preventionTips":["Only pass binary blocks produced by configtxgen or peer channel fetch.","Verify file integrity (checksum) after container/host transfers.","Don't gzip or base64-transform blocks without decoding before use.","Keep block and envelope artifacts in clearly named separate files."],"tags":["protobuf","validation","hyperledger-fabric"],"backgroundTag":"protobuf-unmarshal-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"}