AWS lambda calculator

aws-lambda-calculator.go

package main

import (
	"flag"
	"fmt"
)

type Pricing struct {
	Region          string
	PerRequestPrice float64 // in USD per 1 million requests
	PerMemoryPrice  float64 // in USD per GB-second
}

var pricingByRegion = map[string]Pricing{
	"us-east-1": {
		Region:          "US East (N. Virginia)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"us-east-2": {
		Region:          "US East (Ohio)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"us-west-1": {
		Region:          "US West (N. California)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"us-west-2": {
		Region:          "US West (Oregon)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"af-south-1": {
		Region:          "Africa (Cape Town)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001833,
	},
	"ap-east-1": {
		Region:          "Asia Pacific (Hong Kong)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00002333,
	},
	"ap-south-1": {
		Region:          "Asia Pacific (Mumbai)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"ap-northeast-3": {
		Region:          "Asia Pacific (Osaka-Local)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00002,
	},
	"ap-northeast-2": {
		Region:          "Asia Pacific (Seoul)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"ap-southeast-1": {
		Region:          "Asia Pacific (Singapore)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"ap-southeast-2": {
		Region:          "Asia Pacific (Sydney)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"ap-northeast-1": {
		Region:          "Asia Pacific (Tokyo)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"ca-central-1": {
		Region:          "Canada (Central)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"eu-central-1": {
		Region:          "EU (Frankfurt)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"eu-west-1": {
		Region:          "EU (Ireland)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"eu-west-2": {
		Region:          "EU (London)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"eu-south-1": {
		Region:          "EU (Milan)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00002,
	},
	"eu-west-3": {
		Region:          "EU (Paris)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"eu-north-1": {
		Region:          "EU (Stockholm)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
	"me-south-1": {
		Region:          "Middle East (Bahrain)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00002,
	},
	"sa-east-1": {
		Region:          "South America (São Paulo)",
		PerRequestPrice: 0.20,
		PerMemoryPrice:  0.00001667,
	},
}

func calculateLambdaCost(region string, memory int, requests int, executionTime int) (float64, error) {

	pricing, ok := pricingByRegion[region]
	if !ok {
		return 0.0, fmt.Errorf("unknown region %s", region)
	}

	gbSec := float64(requests) * float64(memory) / 1024.0

	if executionTime > 1 {
		gbSec = gbSec * (float64(executionTime) / 1000.0) // convert to seconds
	}

	computeCharges := gbSec * pricing.PerMemoryPrice
	requestCharges := float64(requests) / 1000000.0 * pricing.PerRequestPrice
	totalCharges := computeCharges + requestCharges

	return totalCharges, nil
}

var (
	region   string
	memory   int
	requests int
	exectime int
)

func main() {

	flag.StringVar(&region, "rg", "", "Region of AWS run  - us-west-2")
	flag.IntVar(&memory, "mm", 0, "Memory allocated - in MegaByte")
	flag.IntVar(&requests, "rq", 0, "Total of Requests - times/month")
	flag.IntVar(&exectime, "ex", 0, "Execution durationn - time in milliseconds")

	flag.Parse()

	if region == "" {
		region = "us-west-2"
	}

	if memory == 0 {
		memory = 256
	}

	if requests == 0 {
		requests = 10000
	}

	if exectime == 0 {
		exectime = 1000
	}

	costs, err := calculateLambdaCost(region, memory, requests, exectime)
	if err != nil {
		fmt.Println(err)
		return
	}

	fmt.Printf("Allocated Memory: %d MB\n", memory)
	fmt.Printf("No of invocations (request): %d\n", requests)
	fmt.Printf("Execution duration: %d milliseconds\n", exectime)
	fmt.Printf("TotalCharges: $%.3f\n", costs)

}