AWS Reserved Instance discount calculator

aws-ri-discount-calculator calcurates Reserved Instance discount by monthly report csv.

$ bundle exec bin/calc ./PATH_TO_REPORT/AAA775901AAA-aws-billing-csv-YYYY-MM.csv
+--------------+----------------+--------------+--------------+
| account_id   | csv_total_cost | ec2_discount | rds_discount |
+--------------+----------------+--------------+--------------+
| AAA775901AAA | $100.123       | $20.111      | $10.987      |
| BBB748336BBB | $500.03        | $100.456     | $0.0         |
| CCC061764CCC | $10.149        | $0.0         | $0.0         |
| ...          | ...            | ...          | ...          |
| ZZZ654481ZZZ | $1358.917      | $479.434     | $240.934     |
| ------------ | -------------- | ------------ | ------------ |
| total        | $3470.013      | $850.62      | $450.0       |
+--------------+----------------+--------------+--------------+

Index

• Requirements
• Installation
• Usage
• How does it works
• Notes
• License

Requirements

aws-ri-discount-calculator requires the following to run:

• Ruby
• Monthly report csv.

※ No IAM credential required.

Installation

$ git clone <this repository url>
$ cd aws-ri-discount-calculator
$ bundle install

Usage

• table output

$ bundle exec bin/calc ./PATH_TO_REPORT/AAA775901AAA-aws-billing-csv-YYYY-MM.csv
+--------------+----------------+--------------+--------------+
| account_id   | csv_total_cost | ec2_discount | rds_discount |
+--------------+----------------+--------------+--------------+
| AAA775901AAA | $100.123       | $20.111      | $10.987      |
| BBB748336BBB | $500.03        | $100.456     | $0.0         |
| CCC061764CCC | $10.149        | $0.0         | $0.0         |
| ...          | ...            | ...          | ...          |
| ZZZ654481ZZZ | $1358.917      | $479.434     | $240.934     |
| ------------ | -------------- | ------------ | ------------ |
| total        | $3470.013      | $850.62      | $450.0       |
+--------------+----------------+--------------+--------------+

• tsv output (for paste Excel etc...)

$ bundle exec bin/calc ./PATH_TO_REPORT/AAA775901AAA-aws-billing-csv-YYYY-MM.csv tsv
account_id	csv_total_cost	ec2_discount	rds_discount
AAA775901AAA	$100.123	$20.111	$10.987
BBB748336BBB	$500.03	$100.456	$0.0
CCC061764CCC	$10.149	$0.0	$0.0
...	...	...	...
ZZZ654481ZZZ	$1358.917	$479.434	$240.934

How does it works

1. Parse monthly report csv.
2. Find line for reserved instance usage. Retrieve BlendedRate, UsageQuantity.
3. Retrieve Ondemand Price by AWS Price List API
4. Calculate (Ondemand Price - BlendedRate) * UsageQuantity.

Notes

• Implemented services are EC2 RDS only.
• XXX_discount columns DON'T include(subtract) purchase costs of RI.

License

MIT

Author

Satoshi Tajima