What is the correct approach to extract data from the cloudwatch agent json file below to create a terraformcloudwatch alarm and send it to SNS as notification.

cloudwatch agent json file

name of the file cloudwatchagent.json

{"metrics": {"metrics_collected": {"disk": {"measurement": ["used_percent",                       # this is the data i need to extract                ],"metrics_collection_interval": 60,"resources": ["*"                ]            },        }    }}

cloudwatch terraform configuration

resource "aws_cloudwatch_metric_alarm""disk-space" {  alarm_name                = "web-disk-space"  comparison_operator       = "GreaterThanOrEqualToThreshold"  evaluation_periods        = "1"  metric_name               = "???"           # not sure what to use here since `used_percent` data are in the json file  namespace                 = "AWS/EC2"  period                    = "120"  statistic                 = "Average"  threshold                 = "1"  alarm_description         = "This metric send an alarm to avoid running out of disk space"  alarm_actions             = [ "${aws_sns_topic.alarm.arn}" ]  dimensions {    InstanceId = "${aws_instance.foo.id}"       # send the data to aws SNS  }}