List of Access Keys from Output Values after ARM Template Deployment

CosmosDb.json

{
  "variables": {
    "cosmosDbAccount": {
      "name": "my-cosmos-db"
    },
    "resourceId": "[resourceId('Microsoft.DocumentDB/databaseAccounts', variables('cosmosDbAccount').name)]",
    "apiVersion": "[providers('Microsoft.DocumentDB', 'databaseAccounts').apiVersions[0]]"
  },
  "resources": [],
  "outputs": {
    "documentEndpoint": {
      "type": "string",
      "value": "[reference(variables('resourceId'), variables('apiVersion')).documentEndpoint]"
    },
    "accountKey": {
      "type": "string",
      "value": "[listKeys(variables('resourceId'), variables('apiVersion')).primaryMasterKey]"
    },
    "connectionString": {
      "type": "string",
      "value": "[concat('AccountEndpoint=https://', variables('cosmosDbAccount').name, '.documents.azure.com:443/;AccountKey=', listKeys(variables('resourceId'), variables('apiVersion')).primaryMasterKey, ';')]"
    }
  }
}