revit-failure-handling

# Revit Failure Handling `RevitApiContext.BeginFailureSuppressionScope` returns a disposable scope that resolves or cancels Revit failures. Use it only for a known failure the operation can safely handle — never to make an unknown failure appear successful. ## When to use - A predictable warning or recoverable error blocks a headless operation (opening, family load, transaction commit). - Reviewing that suppression is bounded to the operation that raises the failure. ## When not to use - The interruption is a UI dialog, not a failure — use `RevitContext.BeginDialogSuppressionScope`. - The API is being called from outside the API context — dispatch the work through a Toolkit external event. ## Workflow ### Step 1: Bound the suppression scope Wrap only the operation that raises the expected failure, and run unrelated work outside the scope. The scope subscribes to the application-level `FailuresProcessing` event, and it applies to both a transaction commit and a document open. ```csharp using (RevitApiContext.BeginFailureSuppressionScope()) { using var transaction = new Transaction(document, "Operation"); transaction.Start(); // ... operation that raises the expected failure transaction.Commit(); } ``` Opening a file can raise the same recoverable warnings. In an unattended or headless host, for example Autodesk Design Automation, no user can dismiss the warning. Open the document inside the scope: ```csharp using (RevitApiContext.BeginFailureSuppressionScope()) { var document = RevitApiContext.Application.OpenDocumentFile(path); } ``` ### Step 2: Choose resolve or cancel The default resolves resolvable failures. Pass `resolveErrors: false` when the caller must observe unresolved errors, not auto-resolve them. ### Step 3: Verify Assert the resulting document or artifact is valid, and confirm the normal error boundary still receives an unrelated failure. ## Validation - [ ] The suppressed failure is known and expected. - [ ] The scope covers one bounded operation, not unrelated work. - [ ] The resulting model or file remains valid. - [ ] Unrelated failures remain observable. ## Common Pitfalls | Pitfall | Correct approach | |----------------------------------------------------------|-----------------------------------------------------------------------| | Wrapping a whole pipeline to hide any failure | Scope suppression to the one operation that raises the known failure. | | Suppressing a UI dialog with a failure scope | Use `RevitContext.BeginDialogSuppressionScope`. | | Auto-resolving errors the caller must process manually | Pass `resolveErrors: false`. | | `RevitApiContext` not found | The `Nice3point.Revit.Toolkit` package is not referenced. |