Azure: Assign Roles via ARM Template to storage container - azure

Question

I'm trying to assign the role "Storage Blob Data Contributor (Preview)" to a specific storage container via arm template. But I just can't figure out the correct syntax.
This is what I have:
{
"$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"principalId": {
"type": "string",
"metadata": {
"description": "The principal to assign the role to"
}
},
"builtInRoleType": {
"type": "string",
"allowedValues": [
"Contributor",
"Reader",
"StorageBlobDataContributor"
],
"metadata": {
"description": "Built-in role to assign"
}
}
},
"variables": {
"apiVersion": "2017-05-01",
"Owner": "[concat('/subscriptions/', subscription().subscriptionId, '/providers/Microsoft.Authorization/roleDefinitions/', '8e3af657-a8ff-443c-a75c-2fe8c4bcb635')]",
"Contributor": "[concat('/subscriptions/', subscription().subscriptionId, '/providers/Microsoft.Authorization/roleDefinitions/', 'b24988ac-6180-42a0-ab88-20f7382dd24c')]",
"Reader": "[concat('/subscriptions/', subscription().subscriptionId, '/providers/Microsoft.Authorization/roleDefinitions/', 'acdd72a7-3385-48ef-bd42-f606fba81ae7')]",
"StorageBlobDataContributor": "[concat('/subscriptions/', subscription().subscriptionId, '/providers/Microsoft.Authorization/roleDefinitions/', 'ba92f5b4-2d11-453d-a403-e96b0029c9fe')]",
"TestVariable": "[concat('STORAGEACCOUNTNAME','/Microsoft.Authorization/',guid(subscription().subscriptionId))]"
},
"resources": [
{
"type": "Microsoft.Storage/storageAccounts/providers/roleAssignments",
"apiVersion": "[variables('apiVersion')]",
"name": "[variables('TestVariable')]",
"properties": {
"roleDefinitionId": "[variables('Reader')]",
"principalId": "[parameters('principalId')]"
}
},
{
"type": "Microsoft.Storage/storageAccounts/STORAGEACCOUNTNAME/blobServices/containers/blobCONTAINERNAME/providers/Microsoft.Authorization/roleAssignments",
"apiVersion": "[variables('apiVersion')]",
"name": "STORAGEACCOUNTNAME/blobServices/containers/default/blobCONTAINERNAME/Microsoft.Authorization/NEW-GUID",
"properties": {
"roleDefinitionId": "[variables('StorageBlobDataContributor')]",
"principalId": "[parameters('principalId')]"
}
}
],
"outputs": {}
}
I can attach the reader role to the storage account itself succesfully.
But for the container I get the following error:
new-AzResourceGroupDeployment : 09:21:24 - Error: Code=InvalidTemplate; Message=Deployment template validation failed: 'The template resource
'STORAGEACCOUNTNAME/blobServices/containers/CONTAINERNAME/Microsoft.Authorization/GUID' for type
'Microsoft.Storage/storageAccounts/STORAGEACCOUNTNAME/blobServices/default/containers/CONTAINERNAME/providers/Microsoft.Authorization/roleAssignments' at line '44' and column '9' has incorrect
segment lengths. A nested resource type must have identical number of segments as its resource name. A root resource type must have segment length one greater than its resource name. Please see
https://aka.ms/arm-template/#resources for usage details.'.
I have tried so many ways trying to attach the role, that I out of idea's.
Can someone help me?

Answer 1

you need to construct something like this:
resourceId/Microsoft.Authorization/roleAssignments/NEW-GUID
and resourceId is normally being constructed as
type: provider/namespace
name: name
provider/namespace/name
for example, for subnet it would be (notice it takes 1 segment from each line in turn, except for the first one, first one is always 2 segments):
type: microsoft.network/virtualnetworks/subnets
name: vnetName/subnetName
microsoft.network/virtualnetworks/vnetName/subnets/subnetName
if that is even possible it would look like something like this:
"type": "Microsoft.Storage/storageAccounts/blobServices/containers/providers/roleAssignments",
"name": "STORAGEACCOUNTNAME/default/CONTAINERNAME/Microsoft.Authorization/NEW-GUID"
Microsoft.Storage/storageAccounts/STORAGEACCOUNTNAME/containers/CONTAINERNAME/providers/Microsoft.Authorization/roleAssignments/NEW-GUID

Answer 2

Made some little adjustments:
"type": "Microsoft.Storage/storageAccounts/blobServices/containers/providers/roleAssignments",
"name": "STORAGEACCOUNTNAME/default/CONTAINERNAME/Microsoft.Authorization/NEW-GUID"
This way I can assign roles on the container itself. Thanks 4c74356b41 for pointing me in the right direction

Answer 3

Using Erik's answer above (which I've up-voted of course, thx Erik!), I was able to solve the similar issue for RBAC permissions on a Queue of a Storage Account using ARM templates.
Here is an example ARM template for adding Sender role to a single Queue of a Storage Account...
<..snip..>
"parameters": {
"PrincipalId": {
"type": "string",
"minLength": 36,
"maxLength": 36
}
},
"variables": {
"SubscriptionId": "[concat('/subscriptions/', subscription().subscriptionId)]",
"RoleDefinitions": "[concat(variables('SubscriptionId'), '/providers/Microsoft.Authorization/roleDefinitions/')]",
"QueueSenderRole": "c6a89b2d-59bc-44d0-9896-0f6e12d7b80a"
},
"resources": [
{
"type": "Microsoft.Storage/storageAccounts/queueServices/queues/providers/roleAssignments",
"name": "mystorageaccount/default/myqueue/Microsoft.Authorization/00000000-1234-0000-5678-000000000000", // NB example only; pick an idempotent but unique value
"apiVersion": "2018-09-01-preview",
"properties": {
"roleDefinitionId": "[concat(variables('RoleDefinitions'), variables('QueueSenderRole'))]",
"principalId": "[parameters('PrincipalId')]"
}
}
]