{"record":{"id":"d83908c937709d6a","repo":"apache/beam","slug":"unable-to-genereate-schema-uuid-for-type-s-v","errorCode":null,"errorMessage":"unable to genereate schema uuid for type %s: %v","messagePattern":"unable to genereate schema uuid for type (.+?): (.+?)","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"sdks/go/pkg/beam/core/runtime/graphx/schema/schema.go","lineNumber":87,"sourceCode":"\n// RegisterType converts the type to it's schema representation, and converts it back to\n// a synthetic type so we can map from the synthetic type back to the user type.\n// Recursively registers other named struct types in any component parts.\nfunc RegisterType(ut reflect.Type) {\n\tdefaultRegistry.RegisterType(ut)\n}\n\n// getUUID generates a UUID using the string form of the type name.\nfunc getUUID(ut reflect.Type) string {\n\t// String produces non-empty output for pointer and slice types.\n\ttypename := ut.String()\n\thasher := fnv.New128a()\n\tif n, err := hasher.Write([]byte(typename)); err != nil || n != len(typename) {\n\t\tpanic(fmt.Sprintf(\"unable to generate schema uuid for %s, wrote out %d bytes, want %d: err %v\", typename, n, len(typename), err))\n\t}\n\tid, err := uuid.NewRandomFromReader(bytes.NewBuffer(hasher.Sum(nil)))\n\tif err != nil {\n\t\tpanic(fmt.Sprintf(\"unable to genereate schema uuid for type %s: %v\", typename, err))\n\t}\n\treturn id.String()\n}\n\n// Registered returns whether the given type has been registered with\n// the schema package.\nfunc (r *Registry) Registered(ut reflect.Type) bool {\n\tr.reconcileRegistrations()\n\tr.rwmu.RLock()\n\tdefer r.rwmu.RUnlock()\n\t_, ok := r.syntheticToUser[ut]\n\treturn ok\n}\n\nvar sdfRtrackerType = reflect.TypeOf((*sdf.RTracker)(nil)).Elem()\n\n// RegisterType converts the type to it's schema representation, and converts it back to\n// a synthetic type so we can map from the synthetic type back to the user type.","sourceCodeStart":69,"sourceCodeEnd":105,"githubUrl":"https://github.com/apache/beam/blob/12126d8942aaf848030c478b4c6a28c6af861c66/sdks/go/pkg/beam/core/runtime/graphx/schema/schema.go#L69-L105","documentation":"After hashing the typename, getUUID seeds uuid.NewRandomFromReader with the digest to produce a deterministic UUID. If that call errors, the library panics because schema UUID generation is fundamental and cannot meaningfully continue.","triggerScenarios":"fromType or structToSchema calling getUUID when uuid.NewRandomFromReader fails — practically only when the reader cannot supply 16 bytes, indicating an internal bug.","commonSituations":"Effectively unreachable in normal use; would surface as an internal invariant break during schema registration or serialization.","solutions":["Retry the operation","Upgrade the Beam SDK / google/uuid dependency to a fixed version","File a bug with a reproducing stack trace if it persists"],"exampleFix":null,"handlingStrategy":"try-catch","validationCode":null,"typeGuard":null,"tryCatchPattern":"defer func() { if r := recover(); r != nil { err = fmt.Errorf(\"schema uuid generation failed: %v\", r) } }()","preventionTips":["Keep the google/uuid dependency current","Retry on transient failures","File a bug if reproducible — this signals an internal bug"],"tags":["go","apache-beam","schema","uuid","panic"],"backgroundTag":"internal-invariant-violation","analyzedSha":"12126d8942aaf848030c478b4c6a28c6af861c66","analyzedAt":"2026-09-13T01:50:10.254Z","contentChangedAt":"2026-09-13T01:50:10.254Z","schemaVersion":2},"datasetVersion":"2026-09-20T03:17:13.778Z"}