create-install-domain.sh

#!/bin/bash

#   usage: ./create-install-domain.sh <github_repo> <domain>
# example: ./create-install-domain.sh kaorimatz/dotfiles dot.kaorimatz.org

set -e
set -u

S3_REGION=ap-northeast-1
S3_HOSTED_ZONE_ID=Z2M4EHUR26P7ZW
S3_WEBSITE_ENDPOINT=s3-website-ap-northeast-1.amazonaws.com

github_repo=$1
domain=$2

# Create an empty bucket
aws s3api create-bucket --bucket "$domain" --create-bucket-configuration LocationConstraint="$S3_REGION"

# Apply a routing rule which redirects to your install script
# https://docs.aws.amazon.com/AmazonS3/latest/dev/HowDoIWebsiteConfiguration.html
aws s3api put-bucket-website --region "$S3_REGION" --bucket "$domain" --website-configuration "$(cat <<EOF
{
    "IndexDocument": {
        "Suffix": "index.html"
    },
    "RoutingRules": [
        {
            "Redirect": {
                "ReplaceKeyWith": "$github_repo/master/install.sh",
                "HostName": "raw.githubusercontent.com",
                "Protocol": "https",
                "HttpRedirectCode": "301"
            }
        }
    ]
}
EOF
)"

# Get the hosted zone id of Route53
hosted_zone_name=$(echo "$domain" | awk -F '.' '{ printf "%s.%s.", $(NF-1), $NF }')
hosted_zone_id=$(aws route53 list-hosted-zones --output text --query "HostedZones[?Name==\`$hosted_zone_name\`].Id")

# Create A record pointing to the created bucket
aws route53 change-resource-record-sets --hosted-zone-id "$hosted_zone_id" --change-batch "$(cat <<EOF
{
  "Changes": [
    {
      "Action": "CREATE",
      "ResourceRecordSet": {
        "Name": "$domain.",
        "Type": "A",
        "AliasTarget": {
          "HostedZoneId": "$S3_HOSTED_ZONE_ID",
          "DNSName": "$S3_WEBSITE_ENDPOINT.",
          "EvaluateTargetHealth": false
        }
      }
    }
  ]
}
EOF
)"