How can I set dependencies on child resources in nested ARM template? - azure

Question

I am trying to use nested templates to deploy a resource group and multiple resources within it on subscription level.
Microsoft documentation has an example of deploying resource group and storage account that I'm trying to follow. I am trying to create another inner level of dependency between a Storage Account resource and a Container resource. That is, the container should only be deployed after the deployment of the storage account is finished. Here is simplified version of my template:
{
"$schema": "https://schema.management.azure.com/schemas/2018-05-01/subscriptionDeploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"rgName": {
"type": "string"
},
"rgLocation": {
"type": "string"
},
"storagePrefix": {
"type": "string",
"maxLength": 11
},
"containerName": {
"type": "string"
}
},
"variables": {
"storageName": "[concat(parameters('storagePrefix'), uniqueString(subscription().id, parameters('rgName')))]"
},
"resources": [
{
"type": "Microsoft.Resources/resourceGroups",
"apiVersion": "2021-04-01",
"name": "[parameters('rgName')]",
"location": "[parameters('rgLocation')]",
"properties": {}
},
{
"type": "Microsoft.Resources/deployments",
"apiVersion": "2021-04-01",
"name": "storageDeployment",
"resourceGroup": "[parameters('rgName')]",
"dependsOn": [
"[resourceId('Microsoft.Resources/resourceGroups/', parameters('rgName'))]"
],
"properties": {
"mode": "Incremental",
"template": {
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {},
"variables": {},
"resources": [
{
"type": "Microsoft.Storage/storageAccounts",
"apiVersion": "2021-04-01",
"name": "[variables('storageName')]",
"location": "[parameters('rgLocation')]",
"sku": {
"name": "Standard_LRS"
},
"kind": "StorageV2"
},
{
"type": "Microsoft.Storage/storageAccounts/blobServices/containers",
"apiVersion": "2021-06-01",
"name": "[format('{0}/default/{1}', variables('storageName'), parameters('containerName'))]",
"dependsOn": [
"[resourceId('Microsoft.Storage/storageAccounts', variables('storageName'))]"
]
}
],
"outputs": {}
}
}
}
],
"outputs": {}
}
When I try to deploy this template using PowerShell script New-AzSubscriptionDeployment, I get the following error:
| InvalidTemplate - Long running operation failed with status 'Failed'. Additional Info:'Deployment template validation failed: 'The resource 'Microsoft.Storage/storageAccounts/myStorageAccount' is not defined in the template. Please see https://aka.ms/arm-template for usage details.'.'
I kind of know it has to do with the dependsOn part of the container resource. But how can I resolve this problem?
EDIT: The selected answer solves the problem with dependencies, however the issue still persists in cases where a value needs to be called using concat or listKeys expressions. Here's an example where setting the value for AzureWebJobsStorage throws an error in a nested template:
{
"type": "Microsoft.Web/sites",
[ ... ]
"dependsOn": [
"[variables('hostingPlanName')]",
"[variables('functionAppStorageAccountName')]"
],
"properties": {
"serverFarmId": "[variables('hostingPlanName')]",
"siteConfig": {
"appSettings": [
{
"name": "AzureWebJobsStorage",
"value": "[concat('DefaultEndpointsProtocol=https;AccountName=', variables('functionAppstorageAccountName'), ';EndpointSuffix=', environment().suffixes.storage, ';AccountKey=',listKeys(resourceId('Microsoft.Storage/storageAccounts', variables('functionAppstorageAccountName')), '2021-04-01').keys[0].value)]"
}
[ ... ]
]
}
The value for AzureWebJobsStorage causes the deployment to fail with the following error:
`Status Message: The Resource 'Microsoft.Storage/storageAccounts/stfuncaedotestfeb16g' under resource group '<null>' was not found. For more details
| please go to https://aka.ms/ARMResourceNotFoundFix (Code:ResourceNotFound) CorrelationId: 55942377-6d0f-40ec-9733-33b9c3ea13de
I tried being more verbose by using resource group name (and then subscription ID), but that didn't solve the problem.

Answer 1

You should be able to use:
"dependsOn": [
"[variables('storageName')]"
]
Note that will only work if there is no other resource in the template with the same name - otherwise you have to manually construct the full resourceId, like:
[format('{0}/resourceGroups/{1}/providers/Microsoft.Storage/storageAccounts/{2}', subscription().id, parameters('rgName'), variables('storageName'))]
The latter form will always work, just a bit more verbose.
A bit more detail is that the resourceId function doesn't work as you would expect at subscription scope.