Azure ARM copy Index not working in Json

Question

I am trying to deploy multiple Azure VNETs using the code below,it

it gives error below

{
  "error": {
    "code": "InvalidTemplate",
    "details": null,
    "message": "Deployment template validation failed: 'The template resource '[concat(variables('namePrefix'), parameters('VNetSettings').vnets.name, [copyIndex(1)])]' at line '1' and column '923' is not valid: The language expression property 'name' has an invalid array index.. Please see https://aka.ms/arm-template-expressions for usage details.'.",
    "target": null
  },
  "properties": null
}

This is my Code below. I want to use coyIndex to loop through multiple instances of azure virtual networks. Based on number of vnet names provided i want it get number of instances to be created.

{
    "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "VNetSettings": {
            "type": "object"
        },
        "namingSettings": {
            "type": "object"
        }
    },
    "variables": {
        "namePrefix": "[concat(parameters('namingSettings').name.org,'-',parameters('namingSettings').name.accountEnv,'-',parameters('namingSettings').name.sdlcEnv,'-',parameters('namingSettings').name.region,'-',parameters('namingSettings').name.appname,'-')]"
    },
    "resources": [
        {
            "apiVersion": "2018-04-01",
            "type": "Microsoft.Network/virtualNetworks",
            "name": "[concat(variables('namePrefix'), parameters('VNetSettings').vnets.name, [copyIndex(1)])]",
            "location": "[resourceGroup().location]",
            "copy": {
                "name": "vnetcopy",
                "count": "[length(parameters('VNetSettings').vnets.name)]"
            },
            "scale": null,
            "properties": {
                "addressSpace": {
                    "addressPrefixes": [
                        "[parameters('VNetSettings').vnets.cidr]"
                    ]
                }
            }
        }
    ]
}

Update

Parameter fileenter code here

{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentParameters.json#",
  "contentVersion": "1.0.0.0",

  "parameters":{
     "namingSettings": {
      "value": {
        "name": {
          "org": "it",
          "accountEnv": "nonprod",
          "sdlcEnv": "it-test",
          "region": "eastus2",
          "tier": "",
          "object": "",
          "networkbuild": "network",
          "auditbuild": "audit",
          "automationbuild": "automation",
          "dnsbuild": "dns",
          "appname": "network"
        }
      }
    },
     "VNetSettings": {
      "value": {
        "vnets": [
          {
            "name": "vnet0",
            "cidr": "10.10.10.0/24",
          }
        ],

        }
    }
}
}

your name prefix looks really long, you WILL run into issues with it — 4c74356b41, Aug 05 '18 at 16:00
what is the recommendation to achieve intended resource name ? — pcz, Aug 05 '18 at 17:10
i have no idea what is your desired resource name, but storage accounts have 24 character limit (and dont allow `-`) windows vms have 15 character limit unless you change the OS name and so on — 4c74356b41, Aug 05 '18 at 17:20

4c74356b41 · Accepted Answer · 2018-08-05T17:20:11.080

Your concat() input is wrong. copyIndex() should not be inside []. Try this:

"[concat(variables('namePrefix'), parameters('VNetSettings').vnets.name, copyIndex(1))]"

copyIndex() is just another function, you only wrap the string with [] once no matter how many functions are inside

you need to adjust your template to reflect the fact you are iterating over an array (right now you iterate over the name, and vnets.name is not a valid construct in the ARM Templates).

you need to do something like this:

{
    "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "VNetSettings": {
            "type": "object"
        },
        "namingSettings": {
            "type": "object"
        }
    },
    "variables": {
        "namePrefix": "[concat(parameters('namingSettings').name.org,'-',parameters('namingSettings').name.accountEnv,'-',parameters('namingSettings').name.sdlcEnv,'-',parameters('namingSettings').name.region,'-',parameters('namingSettings').name.appname,'-')]"
    },
    "resources": [
        {
            "apiVersion": "2018-04-01",
            "type": "Microsoft.Network/virtualNetworks",
            "name": "[concat(variables('namePrefix'), parameters('VNetSettings').vnets[copyIndex()].name)]",
            "location": "[resourceGroup().location]",
            "copy": {
                "name": "vnetcopy",
                "count": "[length(parameters('VNetSettings').vnets)]"
            },
            "scale": null,
            "properties": {
                "addressSpace": {
                    "addressPrefixes": [
                        "[parameters('VNetSettings').vnets[copyIndex()].cidr]"
                    ]
                }
            }
        }
    ]
}

notice you need to use copyIndex() to get to the current vnet in your array and you need to use the .vnet to determine length

Thank you for the answer ! I tried it ,it still gives same error — pcz, Aug 05 '18 at 16:07
could you provide parameters file? you can change all the names, but the structure has to be the same — 4c74356b41, Aug 05 '18 at 16:12
Added parameter file in the question under `updated` section — pcz, Aug 05 '18 at 16:59
by the way, the error you got kinda suggested what you were doing wrong, you were trying to access a `.name` index\method of array, which it complained about — 4c74356b41, Aug 05 '18 at 18:02
oh,okay. I am pretty new to json and Azure ARMS templates. I read about copyIndex and count method but was not getting syntax correct .Thanks again ! — pcz, Aug 05 '18 at 18:10

Azure ARM copy Index not working in Json

Update

1 Answers1