The Amazon Resource Name (ARN) of the CloudWatch Logs log group or Kinesis Data Firehose delivery stream to receive access logs. If you specify a Kinesis Data Firehose delivery stream, the stream name must begin with amazon-apigateway-.
amazon-apigateway-
A single line format of the access logs of data, as specified by selected $context variables. The format must include at least $context.requestId.
$context.requestId