fix_s3_headers.rb

require 'aws-sdk'

AWS.config({
  access_key_id: '',
  secret_access_key: ''
})

s3 = AWS::S3.new

bucket = s3.buckets['bucket-name']

bucket.objects.each do |obj|
  puts "Updating #{obj.key}"
  content_type = case obj.key.split('.')[1]
    when 'png'
      'image/png'
    when 'jpg'
      'image/jpeg'
    when 'jpeg'
      'image/jpeg'
    when 'gif'
      'image/gif'
  end

  obj.copy_from(
    obj.key,
    {
      :metadata => {},
      :acl => :public_read,
      :content_type => content_type,
      :cache_control => 'max-age=4838400, public',
      :expires => 'Wed, 19 Apr 2023 23:10:13 GMT+00:00',
    }
  )
end