hermes

• AWS Cost Optimization Library

Motivation

In order to reduce AWS cost, It is necessary to effectively buy Reserved Instances. But AWS pricing is complicated and difficult. This library shows the RI that you should buy now, based on the future instance usage and the current RI purchase.

Required

# set aws credential "example" with iam policy "hermes"

$ cat ~/.aws/credentials
[example]
aws_access_key_id = ********************
aws_secret_access_key = ****************************************

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "hermes",
      "Effect": "Allow",
      "Action": [
        "ec2:DescribeReserved*",
        "rds:DescribeReserved*",
        "elasticache:DescribeReserved*",
        "organizations:List*",
        "organizations:Describe*",
        "ce:Get*"
      ],
      "Resource": "*"
    }
  ]
}

Install

$ go get github.com/itsubaki/hermes

CommandLine Example

$ AWS_PROFILE=example hermes fetch
write: /var/tmp/hermes/pricing/ap-northeast-1.out
write: /var/tmp/hermes/pricing/us-west-2.out
write: /var/tmp/hermes/usage/2019-08.out
write: /var/tmp/hermes/usage/2019-07.out
write: /var/tmp/hermes/usage/2019-06.out
write: /var/tmp/hermes/usage/2019-04.out
write: /var/tmp/hermes/usage/2019-03.out
write: /var/tmp/hermes/usage/2019-02.out
write: /var/tmp/hermes/usage/2019-01.out
write: /var/tmp/hermes/usage/2018-12.out
write: /var/tmp/hermes/usage/2018-11.out
write: /var/tmp/hermes/usage/2018-10.out
write: /var/tmp/hermes/usage/2018-09.out

$ AWS_PROFILE=example hermes pricing | jq .
[
  {
    "Version": "20190730012138",
    "SKU": "PDMPNVN5SPA5HWHH",
    "OfferTermCode": "6QCMYABX3D",
    "Region": "ap-northeast-1",
    "InstanceType": "ds1.8xlarge",
    "UsageType": "APN1-Node:dw.hs1.8xlarge",
    "LeaseContractLength": "1yr",
    "PurchaseOption": "All Upfront",
    "OnDemand": 9.52,
    "ReservedQuantity": 49020,
    "ReservedHrs": 0,
    "Tenancy": "",
    "PreInstalled": "",
    "OperatingSystem": "",
    "Operation": "RunComputeNode:0001",
    "CacheEngine": "",
    "DatabaseEngine": "",
    "OfferingClass": "standard",
    "NormalizationSizeFactor": ""
  }
  ...
]

$ AWS_PROFILE=example hermes usage | jq .
[
  {
    "account_id": "123456789012",
    "description": "example",
    "region": "us-west-2",
    "usage_type": "USW2-NodeUsage:cache.t2.small",
    "cache_engine": "Redis",
    "date": "2019-08",
    "instance_hour": 101,
    "instance_num": 0.135752688172043
  }
  ...
]

$ AWS_PROFILE=example hermes usage --format csv  | column -t -s, | less -S

$ cat purchase.json | hermes | jq .
{
  "region": "ap-northeast-1",
  "usage_type": "APN1-BoxUsage:c4.large",
  "platform": "Linux/UNIX",
  "instance_num": 1648
}

API Example

price := pricing.Price{
  Region:                  "ap-northeast-1",
  UsageType:               "APN1-BoxUsage:c4.large",
  Tenancy:                 "Shared",
  PreInstalled:            "NA",
  OperatingSystem:         "Linux",
  OfferingClass:           "standard",
  LeaseContractLength:     "1yr",
  PurchaseOption:          "All Upfront",
  OnDemand:                0.126,
  ReservedQuantity:        738,
  ReservedHrs:             0,
  NormalizationSizeFactor: "4",
}

forecast := []usage.Quantity{
  {InstanceNum: 120},
  {InstanceNum: 110},
  {InstanceNum: 100},
  {InstanceNum: 90},
  {InstanceNum: 80},
  {InstanceNum: 70},
  {InstanceNum: 60},
  {InstanceNum: 50},
  {InstanceNum: 40},
  {InstanceNum: 30},
  {InstanceNum: 20},
  {InstanceNum: 10},
}

q, _ := BreakEvenPoint(forecast, price)
if q.InstanceNum != 40 {
  t.Errorf("%v", q.InstanceNum)
}