Using CopyIndex and listKeys in outputs section - azure

Question

I'm trying to get the primaryConnectionStrings from an aRM template that creates multiple notification hubs
But I get this error
Error: Code=InvalidTemplate; Message=Deployment template validation failed: 'The template output 'connectionStrings' at line '291' and column '30' is not valid: The
template function 'copyIndex' is not expected at this location. The function can only be used in a resource with copy specified. Please see https://aka.ms/arm-copy for usage details.. Please see
https://aka.ms/arm-template-expressions for usage details.'.
I am clearly missing what this actually means as I've tried various incarnations of the template all of which have a copy for the resource.
I've tried this with a nested template (apologies if i've mangled the template, just removed some extraneous items):
"resources": [
{
"type": "Microsoft.NotificationHubs/namespaces",
"apiVersion": "2017-04-01",
"name": "[parameters('notificationHubName')]",
"location": "[resourceGroup().location]",
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hub Namespace"
},
"sku": {
"name": "[parameters('notificationHubSku')]"
},
"kind": "NotificationHub",
"properties": {
"namespaceType": "NotificationHub"
}
},
{
"type": "Microsoft.NotificationHubs/namespaces/AuthorizationRules",
"apiVersion": "2017-04-01",
"name": "[concat(parameters('notificationHubName'), '/RootManageSharedAccessKey')]",
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hub Namespace Auth Rules"
},
"dependsOn": [
"[resourceId('Microsoft.NotificationHubs/namespaces', parameters('notificationHubName'))]"
],
"properties": {
"rights": [
"Listen",
"Manage",
"Send"
]
}
},
{
"type": "Microsoft.Resources/deployments",
"apiVersion": "2018-05-01",
"name": "[concat('nestedTemplate', copyIndex('notificationHubEntities'))]",
"copy": {
"name": "notificationHubEntities",
"count": "[length(parameters('notificationHubEntities'))]"
},
"properties": {
"mode": "Incremental",
"template": {
"$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"resources": [
{
"type": "Microsoft.NotificationHubs/namespaces/notificationHubs",
"apiVersion": "2017-04-01",
"name": "[concat(parameters('notificationHubName'), '/', parameters('notificationHubEntities')[copyIndex('notificationHubEntities')])]",
"location": "[resourceGroup().location]",
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hubs"
},
"dependsOn": [
"[resourceId('Microsoft.NotificationHubs/namespaces', parameters('notificationHubName'))]"
],
"properties": {
"authorizationRules": []
}
},
{
"type": "Microsoft.NotificationHubs/namespaces/notificationHubs/authorizationRules",
"apiVersion": "2017-04-01",
"name": "[concat(parameters('notificationHubName'), '/',parameters('notificationHubEntities')[copyIndex('notificationHubEntities')],'/DefaultFullSharedAccessSignature')]",
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hub Auth Rules"
},
"dependsOn": [
"[resourceId('Microsoft.NotificationHubs/namespaces/notificationHubs',parameters('notificationHubName'), parameters('notificationHubEntities')[copyIndex('notificationHubEntities')])]",
"[resourceId('Microsoft.NotificationHubs/namespaces', parameters('notificationHubName'))]"
],
"properties": {
"rights": [
"Listen",
"Manage",
"Send"
]
}
},
],
"outputs" : {
"connectionString" : {
"type" : "object",
"value": "[listKeys(resourceId('Microsoft.NotificationHubs/namespaces/NotificationHubs/AuthorizationRules',parameters('notificationHubName'), parameters('notificationHubEntities')[copyIndex('notificationHubEntities')], 'DefaultFullSharedAccessSignature'),'2016-03-01').primaryConnectionString]"
}
}
}
}
}
],
"outputs": {
"connectionStrings" :
{
"type": "array",
"value": "[reference(concat('nestedTemplate', copyIndex('notificationHubEntities'))).outputs.connectionString.value]"
}
}
}
I've also tried with this:
"resources": [
{
"type": "Microsoft.NotificationHubs/namespaces",
"apiVersion": "2017-04-01",
"name": "[parameters('notificationHubName')]",
"location": "[resourceGroup().location]",
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hub Namespace"
},
"sku": {
"name": "[parameters('notificationHubSku')]"
},
"kind": "NotificationHub",
"properties": {
"namespaceType": "NotificationHub"
}
},
{
"type": "Microsoft.NotificationHubs/namespaces/AuthorizationRules",
"apiVersion": "2017-04-01",
"name": "[concat(parameters('notificationHubName'), '/RootManageSharedAccessKey')]",
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hub Namespace Auth Rules"
},
"dependsOn": [
"[resourceId('Microsoft.NotificationHubs/namespaces', parameters('notificationHubName'))]"
],
"properties": {
"rights": [
"Listen",
"Manage",
"Send"
]
}
},
{
"type": "Microsoft.NotificationHubs/namespaces/notificationHubs",
"apiVersion": "2017-04-01",
"name": "[concat(parameters('notificationHubName'), '/', parameters('notificationHubEntities')[copyIndex()])]",
"location": "[resourceGroup().location]",
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hubs"
},
"copy": {
"name": "addNotificationHub",
"count": "[length(parameters('notificationHubEntities'))]"
},
"dependsOn": [
"[resourceId('Microsoft.NotificationHubs/namespaces', parameters('notificationHubName'))]"
],
"properties": {
"authorizationRules": []
}
},
{
"type": "Microsoft.NotificationHubs/namespaces/notificationHubs/authorizationRules",
"apiVersion": "2017-04-01",
"name": "[concat(parameters('notificationHubName'), '/',parameters('notificationHubEntities')[copyIndex()],'/DefaultFullSharedAccessSignature')]",
"copy": {
"name": "addNotificationHub",
"count": "[length(parameters('notificationHubEntities'))]"
},
"tags": {
"Environment": "[parameters('environment')]",
"DisplayName": "Notification Hub Auth Rules"
},
"dependsOn": [
"[resourceId('Microsoft.NotificationHubs/namespaces/notificationHubs',parameters('notificationHubName'), parameters('notificationHubEntities')[copyIndex()])]",
"[resourceId('Microsoft.NotificationHubs/namespaces', parameters('notificationHubName'))]"
],
"properties": {
"rights": [
"Listen",
"Manage",
"Send"
]
}
}
],
"outputs": {
"connectionStrings" :
{
"type": "array",
"value": "[listKeys(resourceId('Microsoft.NotificationHubs/namespaces/NotificationHubs/AuthorizationRules',parameters('notificationHubName'), parameters('notificationHubEntities')[copyIndex()], 'DefaultFullSharedAccessSignature'),'2016-03-01').primaryConnectionString]"
}
}
I've tried using object instead of array but to no avail, so I'm a bit confused, any help would be appreciated as the error message seems misleading to me or I'm just not interpreting it correctly.

Answer 1

To accomplish requirement of creating multiple notification hubs and it's authorization rules, you can use below ARM template.
Template Parameter File (notificationhub.parameters.json):
{
"$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"namespaceName": {
"value": "mm-namespace"
},
"notificationhubNamePrefix": {
"value": "mm-notificationhub"
},
"notificationhubAuthorizationruleNamePrefix": {
"value": "mm-notificationhubAuthorizationrule"
}
}
}
Template File (notificationhub.json):
{
"$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"namespaceName": {
"type": "string",
"defaultValue": "mm-namespace",
"metadata": {
"description": "namespaceName sample description"
}
},
"notificationhubNamePrefix": {
"type": "string",
"defaultValue": "mm-notificationhub",
"metadata": {
"description": "notificationhubName sample description"
}
},
"notificationhubAuthorizationruleNamePrefix": {
"type": "string",
"defaultValue": "mm-notificationhubAuthorizationrule",
"metadata": {
"description": "notificationhubAuthorizationruleName sample description"
}
},
"location": {
"type": "string",
"defaultValue": "[resourceGroup().location]",
"metadata": {
"description": "The location in which the resources should be deployed."
}
},
"notificationhubNameSuffix": {
"type": "array",
"defaultValue": [
"00",
"01",
"02"
]
},
"notificationhubAuthorizationruleNameSuffix": {
"type": "array",
"defaultValue": [
"00",
"01",
"02"
]
}
},
"variables": {},
"resources": [
{
"name": "[parameters('namespaceName')]",
"type": "Microsoft.NotificationHubs/namespaces",
"apiVersion": "2017-04-01",
"location": "[parameters('location')]",
"tags": {},
"sku": {
"name": "Free"
},
"properties": {
"namespaceType": "NotificationHub"
}
},
{
"name": "[concat(parameters('namespaceName'), '/', parameters('notificationhubNamePrefix'), parameters('notificationhubNameSuffix')[copyIndex()])]",
"type": "Microsoft.NotificationHubs/namespaces/notificationHubs",
"apiVersion": "2017-04-01",
"location": "[parameters('location')]",
"sku": {
"name": "Free"
},
"copy": {
"name": "notificationhubscopy",
"count": "[length(parameters('notificationhubNameSuffix'))]"
},
"dependsOn": [
"[resourceId('Microsoft.NotificationHubs/namespaces', parameters('namespaceName'))]"
]
},
{
"name": "[concat(parameters('namespaceName'), '/', parameters('notificationhubNamePrefix'), parameters('notificationhubNameSuffix')[copyIndex()], '/', parameters('notificationhubAuthorizationruleNamePrefix'), parameters('notificationhubAuthorizationruleNameSuffix')[copyIndex()])]",
"type": "Microsoft.NotificationHubs/namespaces/notificationHubs/AuthorizationRules",
"apiVersion": "2017-04-01",
"properties": {
"rights": [
"Listen",
"Manage",
"Send"
]
},
"copy": {
"name": "notificationhubsauthroizationrulescopy",
"count": "[length(parameters('notificationhubAuthorizationruleNameSuffix'))]"
},
"dependsOn": [
"notificationhubscopy"
]
}
]
}
Deployment:
AFAIK, to accomplish requirement of getting output (in this case primaryConnectionStrings of multiple notification hubs' authorization rules) from ARM template is currently an unsupported feature. I already see related feature requests / feedback here and here. I would recommend you to up-vote these feature requests / feedback or create a new feature request / feedback explaining your use case and requirement. Azure feature team would consider and work on the feature request / feedback based on the votes, visibility and priority on it.
Azure document references:
ARM template reference for NotificationHubs
Resolve Invalid Template errors
Create multiple instances of a resource using copy and copyIndex
ARM template functions like list (ListKeys)
ARM template structure
Defining order for deploying resources in ARM templates
Hope this helps!! Cheers!!

Answer 2

You can't use a copy loop in outputs today - listing the keys is fine, but you have to know how many you need at design time and hardcode each output. We're working on a fix for that but not there yet.
You could emulate this by using your second option - deploying in a nested deployment and outputting each key in it's own deployment, but then you have to iterate through all the deployments to get all the outputs.