upload.json

{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "location": {
      "type": "string"
    },
    "uniquePrefix": {
      "type": "string"
    },
    "index": {
      "type": "int"
    },
    "uploadScriptURI": {
      "type": "string"
    }
  },
  "resources": [
    {
      "type": "Microsoft.Compute/virtualMachines/extensions",
      "name": "[concat('transfer', parameters('uniquePrefix'), 'vm/ext')]",
      "apiVersion": "2015-05-01-preview",
      "location": "[parameters('location')]",
      "properties": {
        "publisher": "Microsoft.OSTCExtensions",
        "type": "CustomScriptForLinux",
        "typeHandlerVersion": "1.4",
        "settings": {
          "fileUris": [
            "[parameters('uploadScriptURI')]"
          ]
        },
        "protectedSettings": {
          "commandToExecute": "[concat('bash upload.sh ', concat(uniqueString(concat(resourceGroup().id, parameters('uniquePrefix'), parameters('index'))), parameters('uniquePrefix')), ' ', listKeys(concat('Microsoft.Storage/storageAccounts/', concat(uniqueString(concat(resourceGroup().id, parameters('uniquePrefix'), parameters('index'))), parameters('uniquePrefix'))), '2015-05-01-preview').key1)]"
        }
      }
    }
  ]
}