Exercise - Use copy to reduce repetition

  • 5 minutes

In this final exercise, you continue to work with storage accounts. This time, you use the copy construct to provision multiple storage accounts from a single definition.

Copy gives you a single, central location that you need to update when your requirements change.

Create the ARM template

Here, you create an Azure Resource Manager (ARM) template that defines a storage account resource. The template uses copy to create similar versions of the same resource a specified number of times.

  1. In Visual Studio Code, create a file named copy.json in the same directory that contains azuredeploy.json.

  2. Add these contents to copy.json:

    {
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "storageCount": {
      "type": "int",
      "defaultValue": 1,
      "metadata": {
        "description": "the number of storage accounts copies being deployed"
      }
    },
    "storageAccountName": {
      "type": "string",
      "defaultValue": "storage",
      "metadata": {
        "description": "the name of the storage account"
      }
    }
  },
  "functions": [],
  "variables": {},
  "resources": [
    {
      "name": "[concat(parameters('storageAccountName'), copyIndex())]",
      "type": "Microsoft.Storage/storageAccounts",
      "apiVersion": "2019-06-01",
      "tags": {
        "displayName": "storageaccount1"
      },
      "location": "[resourceGroup().location]",
      "kind": "StorageV2",
      "sku": {
        "name": "Premium_LRS",
        "tier": "Premium"
      },
      "copy": {
        "name": "storagecopy",
        "count": "[parameters('storageCount')]"
      }
    }
  ],
  "outputs": {}
}

The storageCount parameter defines the number of copies to create.

Under resources, note the storage account resource. To make the storage account name unique, the template uses copyIndex() to append the current index to the storage account name.

The copy section reads the number of copies to make from the storageCount parameter.

Deploy the template

Here, you deploy the template as you did previously. The deployment step provisions two similar storage accounts.

  1. Create a PowerShell variable that holds the storage account name.

    $STORAGE_ACCT_NAME="tailwindsa" + (Get-Random -Count 1)

  2. Run the following New-AzResourceGroupDeployment command to deploy the template:

    New-AzResourceGroupDeployment `
-TemplateFile "./copy.json" `
-storageAccountName $STORAGE_ACCT_NAME `
-storageCount 2

    Here, you set storageCount to 2 to provision two storage accounts.

Verify the deployment

Although the output shows that two storage accounts were created, here you run the Get-AzResource command to focus on the output resources.

Run the following Get-AzResource command to ensure the resources were deployed:

Get-AzResource -Name tailwindsa* -ResourceGroupName <rgn>resource group name</rgn> | Select-Object -Property Name,ResourceId

The tailwindsa* argument specifies to show just the identifiers matching the name prefix you gave the resources.

Your output resembles this:

Name                 ResourceId
----                 ----------
tailwindsa1852777810 /subscriptions/11112222-3333-4444-5555-1111222233334444/resourceGroups/<rgn>resoure group</rgn>/providers/Microsoft.Storage/storageAccount…
tailwindsa1852777811 /subscriptions/11112222-3333-4444-5555-1111222233334444/resourceGroups/<rgn>resoure group</rgn>/providers/Microsoft.Storage/storageAccount…

In this example:

  • tailwindsa185277781 is the base name that was generated for the storage account ("tailwindsa" + Get-Random -Count 1).
  • tailwindsa1852777810 (the base name plus "0") is the first storage account.
  • tailwindsa1852777811 (the base name plus "1") is the second storage account.

Great work! As your needs change, such as the performance tier you need, you can modify your resource definitions from a single location.

Clean up

The sandbox automatically cleans up your resources when you're finished with this module.

When you're working in your own subscription, it's a good idea at the end of a project to identify whether you still need the resources you created. Resources that you leave running can cost you money. You can delete resources individually or delete the resource group to delete the entire set of resources.

Create the ARM template

Here, you create an Azure Resource Manager (ARM) template that defines a storage account resource. The template uses copy to create similar versions of the same resource a specified number of times.

  1. In Visual Studio Code, create a file named copy.json in the same directory that contains azuredeploy.json.

  2. Add these contents to copy.json:

    {
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "storageCount": {
      "type": "int",
      "defaultValue": 1,
      "metadata": {
        "description": "the number of storage accounts being deployed"
      }
    },
    "storageAccountName": {
      "type": "string",
      "defaultValue": "storage",
      "metadata": {
        "description": "the name of the storage account"
      }
    }
  },
  "functions": [],
  "variables": {},
  "resources": [
    {
      "name": "[concat(parameters('storageAccountName'), copyIndex())]",
      "type": "Microsoft.Storage/storageAccounts",
      "apiVersion": "2019-06-01",
      "tags": {
        "displayName": "storageaccount1"
      },
      "location": "[resourceGroup().location]",
      "kind": "StorageV2",
      "sku": {
        "name": "Premium_LRS",
        "tier": "Premium"
      },
      "copy": {
        "name": "storagecopy",
        "count": "[parameters('storageCount')]"
      }
    }
  ],
  "outputs": {}
}

The storageCount parameter defines the number of copies to create.

Under resources, note the storage account resource. To make the storage account name unique, the template uses copyIndex() to append the current index to the storage account name.

The copy section reads the number of copies to make from the storageCount parameter.

Deploy the template

Here, you deploy the template as you did previously. The deployment step provisions two similar storage accounts.

  1. Create a Bash variable that holds the storage account name.

    STORAGE_ACCT_NAME=tailwindsa$RANDOM

  2. Run the following az deployment group create command to deploy the template:

    az deployment group create \
  --template-file copy.json \
  --parameters storageAccountName=$STORAGE_ACCT_NAME storageCount=2

    Here, you set storageCount to 2 to provision two storage accounts.

Verify the deployment

Although the output shows that two storage accounts were created, here you run the az deployment group show command to focus on the output resources.

Run the following az deployment group show command to display details about the deployment:

az deployment group show \
  --name copy \
  --query "properties.outputResources[].id" \
  --output tsv

The --query argument specifies to show just the identifiers from the output resources.

Your output resembles this:

/subscriptions/aaaa0a0a-bb1b-cc2c-dd3d-eeeeee4e4e4e/resourceGroups/<rgn>resource group name</rgn>/providers/Microsoft.Storage/storageAccounts/tailwindsa9820
/subscriptions/aaaa0a0a-bb1b-cc2c-dd3d-eeeeee4e4e4e/resourceGroups/<rgn>resource group name</rgn>/providers/Microsoft.Storage/storageAccounts/tailwindsa9821

In this example:

  • tailwindsa982 is the base name that was generated for the storage account (tailwindsa$RANDOM).
  • tailwindsa9820 (the base name plus "0") is the first storage account.
  • tailwindsa9821 (the base name plus "1") is the second storage account.

Great work! As your needs change, such as the performance tier you need, you can modify your resource definitions from a single location.

Clean up

The sandbox automatically cleans up your resources when you're finished with this module.

When you're working in your own subscription, it's a good idea at the end of a project to identify whether you still need the resources you created. Resources that you leave running can cost you money. You can delete resources individually or delete the resource group to delete the entire set of resources.