```ruby
# frozen_string_literal: true

require 'singleton'

module VpnModule
  class S3Certificates
    include Singleton

    @bucket_connection = nil

    def initialize
      credential_stub = Aws::Credentials.new(ENV['S3_KEY'], ENV['S3_SECRET'])
      client_stub = Aws::S3::Client.new(
        region: 'us-east-1',
        credentials: credential_stub,
        stub_responses: Rails.env.test?
      )
      s3 = Aws::S3::Resource.new(client: client_stub)
      @bucket_connection = s3.bucket(ENV['S3_BUCKET'])
    end

    def find_or_create_cert_for(filename)
      certificate_bundle = @bucket_connection.object("#{filename}.zip")
      return certificate_bundle.presigned_url(:get, expires_in: 10.minutes.to_i) if certificate_bundle.exists?
      create_certificate_for(filename)
      nil
    end

    def cert_ready_for?(filename)
      return true if bucket_file_exists?("#{filename}.zip")
      create_certificate_for(filename) unless bucket_file_exists?(filename)
      false
    end

    def bucket_file_exists?(filename)
      @bucket_connection.object(filename).exists?
    end

    def create_certificate_for(filename)
      @bucket_connection.object(filename).put
    end
  end
end
```

Add rescue statements for S3 so that S3 does not cause our whole site to not work if it goes down
user
```ruby
# frozen_string_literal: true

require 'singleton'

module VpnModule
  class S3Certificates
    include Singleton

    @bucket_connection = nil

    def initialize
      credential_stub = Aws::Credentials.new(ENV['S3_KEY'], ENV['S3_SECRET'])
      client_stub = Aws::S3::Client.new(
        region: 'us-east-1',
        credentials: credential_stub,
        stub_responses: Rails.env.test?
      )
      s3 = Aws::S3::Resource.new(client: client_stub)
      @bucket_connection = s3.bucket(ENV['S3_BUCKET'])
    end

    def find_or_create_cert_for(filename)
      certificate_bundle = @bucket_connection.object("#{filename}.zip")
      return certificate_bundle.presigned_url(:get, expires_in: 10.minutes.to_i) if certificate_bundle.exists?
      create_certificate_for(filename)
      nil
    rescue # If S3 errors for any reason then we return nil so that the application does not error
      nil
    end

    def cert_ready_for?(filename)
      return true if bucket_file_exists?("#{filename}.zip")
      create_certificate_for(filename) unless bucket_file_exists?(filename)
      false
    end

    def bucket_file_exists?(filename)
      @bucket_connection.object(filename).exists?
    rescue
      false
    end

    def create_certificate_for(filename)
      @bucket_connection.object(filename).put
    rescue
      false
    end
  end
end
```
assistant