Azure ARM template - Output - reference storage key

Bit tricky, I got stuck here for a bit on the API version:

  
"variables":{
  
"storageAccountName": "[concat('storage', variables('environment'), variables('regionCode'))]",
      
"storageAccountId": "[concat(resourceGroup().id,'/providers/Microsoft.Storage/storageAccounts/', variables('storageAccountName'))]"
  
}
  
…

   
"outputs": {
      
"storageAccountId": {
        
"type": "string",
        
"value": "[listKeys(variables('storageAccountId'),'2015-05-01-preview').key1]"
      
}
  
}
  

Don’t do the mistake I was doing, where using the latest API version doesn’t work:

  
"value": "[listKeys(resourceid('Microsoft.Storage/storageAccounts', variables('storageAccountname')),'2016-01-01′).key1]"