Azure ARM templates - Stream Analytics identity.principalId as output - azure

Question

I have a working ARM Template for a Stream Analytics job which creates it's own 'managed identity' which can be queried using AZ CLI, e.g.:
'az stream-analytics job show -g <resource_group> -n <stream_analytics_job_name> -o json --query 'identity.principalId'
(Deployment is via Terraform 'azurerm_template_deployment' module).
Added an ARM template output to return this key using 'listkeys':
"outputs": {
"principalId": {
"type": "string",
"value": "[listkeys(resourceId('Microsoft.StreamAnalytics/streamingjobs', parameters('StreamAnalyticsJobName')), parameters('ASAApiVersion')).identity.principalId]"
}
}
}
Now the ARM deployment fails as seen in the resource group deployments list with:
{
"code": "DeploymentFailed",
"message": "At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/DeployOperations for usage details.",
"details": [
{
"code": "NotFound",
"message": "{\r\n \"code\": \"NotFound\",\r\n \"message\": \"The webpage cannot be found.\",\r\n \"details\": {\r\n \"code\": \"404\",\r\n \"message\": \"The webpage cannot be found.\",\r\n \"correlationId\": \"<redacted>\",\r\n \"requestId\": \"<redacted>\"\r\n }\r\n}"
}
]
}
From the resource group Activity Log, under the 'Write Steam Analytics Job', there are failed operations for listkeys - none of which give any further clues.
'identity.principalId' found for this Stream Analytics job via https://resources.azure.com:
...etc...
"identity": {
"principalId": "<redacted>",
"tenantId": "<redacted>",
"type": "SystemAssigned"
},
Have also tried the following ARM template output with the same result:
"outputs": {
"principalId": {
"type": "string",
"value": "[listkeys(resourceId('Microsoft.StreamAnalytics/streamingjobs', parameters('StreamAnalyticsJobName')), parameters('ASAApiVersion')).principalId]"
}
}
Similar issues found but none for Stream Analytics:
Azure ARM templates : DocumentDB primaryMasterKey as OUTPUT
How to return Redis primaryKey via ARM template output?
https://devkimchi.com/2018/01/05/list-of-access-keys-from-output-values-after-arm-template-deployment/
Research:
https://learn.microsoft.com/en-us/azure/azure-resource-manager/templates/template-outputs?tabs=azure-powershell
https://learn.microsoft.com/en-us/azure/stream-analytics/powerbi-output-managed-identity
https://www.terraform.io/docs/providers/azurerm/r/template_deployment.html
Any help much appreciated, thanks.

Answer 1

Came across the answer elsewhere (How to get Principal Id in app service using Arm template?) as I was trying to obtain a principal ID not a key (my bad).
Using the following ARM Template output worked:
"outputs": {
"principalId": {
"type": "string",
"value": "[reference(resourceId('Microsoft.StreamAnalytics/streamingjobs', parameters('StreamAnalyticsJobName')), parameters('ASAApiVersion'), 'Full').identity.principalId]"
}
}