creating a new guid at each iteration in an ARM template - azure

Question

I try to script an ARM template like this:
{
"type": "Microsoft.EventHub/namespaces/ipfilterrules",
"apiVersion": "2018-01-01-preview",
"name": "[concat(parameters('name'), '/fr', copyIndex())]",
"location": "[resourceGroup().location]",
"properties": {
"ipMask": "[parameters('ipMasks')[copyIndex()]]",
"action": "Accept",
"filterName": "[concat('fr', copyIndex())]"
},
"copy": {
"name": "eventHubfirewallrulescopy",
"count": "[length(parameters('ipMasks'))]"
}
What I really want to to is to feed "name" and "filtername" by the same GUID value. in order to have something like this:
{
"type": "Microsoft.EventHub/namespaces/ipfilterrules",
"apiVersion": "2018-01-01-preview",
"name": "[concat(parameters('name'), 'd8fb1ab2-a6cb-439f-9354-918bd96d6ace')]",
"location": "[resourceGroup().location]",
"properties": {
"ipMask": "[parameters('ipMasks')[copyIndex()]]",
"action": "Accept",
"filterName": "d8fb1ab2-a6cb-439f-9354-918bd96d6ace"
},
"copy": {
"name": "eventHubfirewallrulescopy",
"count": "[length(parameters('ipMasks'))]"
}
As you can see this is a multi deployement resource. So I need a new guid generated at each iteration.
I first thought to create a variable using guid() function, but it is not permitted.
Is there any other idea?
thank you

Answer 1

How about defining a proxy parameter in the template for which you do not pass the value and is initialed to default new guid and use it in the variables later to generate the unique string? Something like this
{
"$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"guidValue": {
"type": "string",
"defaultValue": "[newGuid()]"
}
},
"variables": {
"unique_string":"[uniqueString(parameters('guidValue'))]"
},
"resources":
[
.. your resources with names derived from variables('unique_string')
],
"outputs": {
"unique_string": {
"type": "string",
"value": "[variables('unique_string')]"
}
}
}
Hope this helps?

Answer 2

If the length of parameters('ipMasks') is known you can use either a pregenerated array of guids with the same length and then use copyIndex to pick the guid in the same way that you pick the ip masks. If a random guid is needed (in my case a static guid was needed) the same scenario with a generated guid list should work:
[
"[newGuid()]",
"[newGuid()]",
"[newGuid()]",
"[newGuid()]",
"[newGuid()]"
]
Assuming a fixed array parameter of 5 items.