{"record":{"id":"b89aa6ed87426831","repo":"clockworklabs/SpacetimeDB","slug":"failed-to-generate-table-due-to-validation-errors-b89aa6","errorCode":null,"errorMessage":"Failed to generate table due to validation errors","messagePattern":"Failed to generate table due to validation errors","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"crates/codegen/src/unrealcpp.rs","lineNumber":1152,"sourceCode":"            let schema = TableSchema::from_module_def(module, table, (), 0.into())\n                .validated()\n                .expect(\"table schema should validate\");\n            let table_cpp_content = generate_table_cpp(self.module_prefix, module, table, self.module_name, &schema);\n            let table_cpp_filename = format!(\n                \"Source/{}/Private/ModuleBindings/Tables/{}Table.g.cpp\",\n                self.module_name,\n                format_args!(\"{module_prefix}{}\", table.name.deref().to_case(Case::Pascal))\n            );\n            files.push(OutputFile {\n                filename: table_cpp_filename,\n                code: table_cpp_content,\n            });\n        }\n        for view in module.views() {\n            let tbl = TableDef::from(view.clone());\n            let schema = TableSchema::from_view_def_for_codegen(module, view)\n                .validated()\n                .expect(\"Failed to generate table due to validation errors\");\n            let view_cpp_content = generate_table_cpp(self.module_prefix, module, &tbl, self.module_name, &schema);\n            let view_cpp_filename = format!(\n                \"Source/{}/Private/ModuleBindings/Tables/{}Table.g.cpp\",\n                self.module_name,\n                format_args!(\"{module_prefix}{}\", view.name.deref().to_case(Case::Pascal))\n            );\n            files.push(OutputFile {\n                filename: view_cpp_filename,\n                code: view_cpp_content,\n            });\n        }\n\n        files\n    }\n}\n\n// Helper function to generate table .cpp implementation files\nfn generate_table_cpp(","sourceCodeStart":1134,"sourceCodeEnd":1170,"githubUrl":"https://github.com/clockworklabs/SpacetimeDB/blob/6dee26c6efc2856793e12b148a59742964f5d783/crates/codegen/src/unrealcpp.rs#L1134-L1170","documentation":"Panic in SpacetimeDB's Unreal Engine C++ binding generator (`spacetime generate --lang cpp` etc.). When generating code for each module view, the generator builds a `TableSchema::from_view_def_for_codegen(...)` and calls `.validated()`; if the view's schema collects any validation errors, `expect` panics and aborts codegen. It means the module's view definition itself is structurally invalid from the schema validator's perspective.","triggerScenarios":"Running codegen for Unreal C++ bindings against a module whose `view` definition fails `TableSchema` validation — e.g. a view projecting unsupported types, mismatched column/index definitions, or a view referencing elements the schema validator rejects. The sibling loop over tables uses the same pattern, so a bad table can also surface here when `TableDef::from(view)` is built.","commonSituations":"Upgrading SpacetimeDB CLI or module SDK versions where view validation rules tightened; hand-editing a `.satellite`/module schema; adding a new view with exotic types (e.g. certain sum types or nested structures) that Unreal codegen cannot map; mixing old generated bindings with a new module.","solutions":["Re-run `spacetime build` / validation on the module to surface the underlying validation error messages before codegen (the panic message itself hides the error list).","Inspect recently added views in the module and remove or fix the one that fails validation (often an unsupported type or bad projection).","Check SpacetimeDB release notes for schema-validation changes and update the module SDK (`spacetime` CLI + `spacetimedb-std`) to matching versions.","If the view is optional for your game client, delete it from the module and regenerate to confirm it is the culprit, then re-add incrementally."],"exampleFix":"// module (before): view with a type Unreal codegen cannot validate\nview BadView { projection: SomeUnsupportedType }\n\n// module (after): project a supported scalar/product type\nview BadView { projection: String }","handlingStrategy":"validation","validationCode":"// Before codegen, validate every table/view schema the same way codegen does\nuse spacetimedb_schema::table::TableSchema;\nfor view in module.views() {\n    if let Err(errors) = TableSchema::from_view_def_for_codegen(module, view).validated() { /* fix errors before generate */ }\n}","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Run `spacetime build` and fix all schema-validation errors before `spacetime generate`.","Keep the CLI and module SDK (`spacetimedb-std`) on the same release line.","Add new views incrementally and regenerate after each addition so failures localize."],"tags":["rust","spacetimedb","codegen","unreal","schema","validation","panic"],"backgroundTag":"schema-validation-failed","analyzedSha":"6dee26c6efc2856793e12b148a59742964f5d783","analyzedAt":"2026-08-20T06:08:37.179Z","contentChangedAt":"2026-08-20T06:08:37.179Z","schemaVersion":2},"datasetVersion":"2026-09-14T00:17:10.932Z"}