Amazon S3 Redirect Rules Generator

README.md

Amazon S3 Redirect Rules Generator

A Ruby script to generate simple Amazon S3 Redirection Rules XML file.

Update: There is an app for that now! Use Amazon S3 Redirector (Web app) and you can generate the XML without any knowledge about Ruby. Thanks to @rainforestapp. BTW, It's open source too.

Dependencies

• Nokogiri

Usage

ruby s3-routes-generator.rb input.txt

The generated XML is printed to STDOUT.

Assumptions on S3 Bucket

It assumes that:

1. Website Hosting is enabled.
2. Index Document is set to index.html.

Conversion Rules

1. For target path, if it ends with /, then index.html will be appended.
2. For source and target path, the leading / will be removed, because S3's object key does not begin with /.

Sample Input

One rule per line. Each rule is constructed by source and target path, spearated by at least 1 space.

Please not that rules are matched using KeyPrefixEquals, and is First-In-First-Out, so if you have multiple redirections from same prefixes (typically /dir and /dir/subdir), please put the longer one before the shorter one, i.e. Depth-First.

/home                        /
/products/iphone/specs.html  /iphone/specs.html
/products/iphone/            /iphone/
/products/ipad/accessories/  /ipad/accessories.html
/products/ipad/              /ipad/
/products                    /

Sample Output

<?xml version="1.0"?>
<RoutingRules>
  <RoutingRule>
    <Condition>
      <KeyPrefixEquals>home</KeyPrefixEquals>
    </Condition>
    <Redirect>
      <ReplaceKeyWith>index.html</ReplaceKeyWith>
    </Redirect>
  </RoutingRule>
  <RoutingRule>
    <Condition>
      <KeyPrefixEquals>products/iphone/specs.html</KeyPrefixEquals>
    </Condition>
    <Redirect>
      <ReplaceKeyWith>iphone/specs.html</ReplaceKeyWith>
    </Redirect>
  </RoutingRule>
  <RoutingRule>
    <Condition>
      <KeyPrefixEquals>products/iphone/</KeyPrefixEquals>
    </Condition>
    <Redirect>
      <ReplaceKeyWith>iphone/index.html</ReplaceKeyWith>
    </Redirect>
  </RoutingRule>
  <RoutingRule>
    <Condition>
      <KeyPrefixEquals>products/ipad/accessories/</KeyPrefixEquals>
    </Condition>
    <Redirect>
      <ReplaceKeyWith>ipad/accessories.html</ReplaceKeyWith>
    </Redirect>
  </RoutingRule>
  <RoutingRule>
    <Condition>
      <KeyPrefixEquals>products/ipad/</KeyPrefixEquals>
    </Condition>
    <Redirect>
      <ReplaceKeyWith>ipad/index.html</ReplaceKeyWith>
    </Redirect>
  </RoutingRule>
  <RoutingRule>
    <Condition>
      <KeyPrefixEquals>products</KeyPrefixEquals>
    </Condition>
    <Redirect>
      <ReplaceKeyWith>index.html</ReplaceKeyWith>
    </Redirect>
  </RoutingRule>
</RoutingRules>

References

• Configure a Bucket for Website Hosting - Amazon Simple Storage Service

License

None. I release this script to Public Domain.

s3-routes-generator.rb

require 'nokogiri'

routes = []

src = File.read(ARGV[0])

src.each_line do |line|
  from, to = line.split(/\s+/)

  from.gsub!(/\A\//, '')
  to.gsub!(/\/\z/, '/index.html')
  to.gsub!(/\A\//, '')

  routes << { :from => from, :to => to }
end

builder = Nokogiri::XML::Builder.new do |xml|
  xml.RoutingRules {
    routes.each do |route|
      xml.RoutingRule {
        xml.Condition {
          xml.KeyPrefixEquals route[:from]
        }

        xml.Redirect {
          xml.ReplaceKeyWith route[:to]
        }
      }
    end
  }
end

puts builder.to_xml

@RameshJhajharia @grantgeorge WIth the standard advanced conditional redirect rules on an S3 bucket, you cannot detect a user agent, you can only act on the key of the request: https://docs.aws.amazon.com/AmazonS3/latest/dev/how-to-page-redirect.html#advanced-conditional-redirects