func (p LambdaPlugin) MetricKeyPrefix() string {
	return p.Prefix
}
MetricKeyPrefix interface for PluginWithPrefix
package mpawslambda
import (
	"flag"
	"log"
	"strings"
	"time"
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/credentials"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/cloudwatch"
	"github.com/aws/aws-sdk-go/service/cloudwatch/cloudwatchiface"
	mp "github.com/mackerelio/go-mackerel-plugin-helper"
)
const (
	namespace          = "AWS/Lambda"
	metricsTypeAverage = "Average"
	metricsTypeSum     = "Sum"
	metricsTypeMaximum = "Maximum"
	metricsTypeMinimum = "Minimum"
)
type metricsGroup struct {
	CloudWatchName string
	Metrics        []metric
}
type metric struct {
	MackerelName string
	Type         string
}
type LambdaPlugin struct {
	FunctionName string
	Prefix       string
	AccessKeyID     string
	SecretAccessKey string
	Region          string
	CloudWatch *cloudwatch.CloudWatch
}