What you need to know
A working createUiDefinition control can still produce a name, type or default that the ARM template does not accept.
Potentially affected
Azure managed-application createUiDefinition.json interfaces paired with ARM templates.
DSE recommendation
Test the UI definition and main template as one parameter contract.
Source facts
The template test toolkit checks that control values in createUiDefinition.json are allowed by the main template’s parameters. Microsoft’s examples fail when parameter names differ or when a template integer parameter receives a control’s string value. A template default must also be one of the control’s allowed values.
For a VM SizeSelector, the tests compare the UI outputs with the main template parameters and require a template default to match the control’s allowedSizes. Microsoft Learn.
Applicability
Identify the exact UI definition and main template released together. Distinguish a control’s displayed label from the output parameter name and the value’s actual type.
DSE recommendation
DSE recommends reviewing every UI output alongside the receiving parameter before publication. Compare names, types, defaults and permitted choices, especially after changing a dropdown or size selector. Keep the two files versioned as one deliverable. Do not bypass a contract failure by accepting all values or changing a parameter type without checking the deployment’s real requirement.
Verification
Run the relevant toolkit tests against the paired files, then exercise representative UI selections in an approved test experience. Include the default and boundary choices, and inspect the resulting parameter values without exposing secrets. Retain both file revisions and test results. A successful portal preview alone should not replace the cross-file validation evidence.
Official references
Microsoft Learn: createUiDefinition.json test cases for Azure Resource Manager test toolkit. Source retrieved September 9, 2026.
Review the official source
createUiDefinition.json test cases for Azure Resource Manager test toolkit - Azure Resource Manager | Microsoft Learn · Verified September 9, 2026
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DSE can help confirm applicability, protect service continuity, and validate the result across physical security and IT systems.
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