in src/main/scala/com/gu/invoicing/common/HttpHelper.scala [15:20]
def queryStringParameterOrThrow(request: APIGatewayProxyRequestEvent, parameterName: String): String = {
request.getQueryStringParameters.asScala.getOrElse(
parameterName,
throw new RuntimeException(s"Query string Parameter $parameterName was missing from the url"),
)
}