From 9560aa2903a7504f92964f19ff2cbf385edbff37 Mon Sep 17 00:00:00 2001
From: Martin Fenner <martin.fenner@datacite.org>
Date: Wed, 12 Apr 2017 18:54:56 +0200
Subject: [PATCH] intial commit

---
 .env                                          |   4 +
 .travis.yml                                   |  14 ++
 CHANGELOG.md                                  |   0
 Dockerfile                                    |  45 ++++
 Gemfile                                       |  30 +++
 Gemfile.lock                                  | 175 +++++++++++++
 LICENSE                                       |   2 +-
 README.md                                     |   4 +-
 app.rb                                        | 161 ++++++++++++
 config.ru                                     |   9 +
 docker-compose.yml                            |  13 +
 lib/content_negotiation.rb                    |   7 +
 lib/helpers.rb                                | 101 ++++++++
 spec/api_spec.rb                              | 164 +++++++++++++
 .../get_registered_content_types/absent.yml   |  40 +++
 .../get_registered_content_types/present.yml  |  40 +++
 .../available_content_type.yml                |  38 +++
 .../registered_content_type.yml               |  40 +++
 .../unsupported_content_type.yml              |  73 ++++++
 .../Helpers/should_pass_thru/doi.yml          |  38 +++
 .../vnd_citationstyles_csl_json/header.yml    |  38 +++
 .../vnd_citationstyles_csl_json/link.yml      |  40 +++
 .../vnd_citationstyles_csl_json/redirect.yml  | 232 ++++++++++++++++++
 .../vnd_datacite_datacite_json/header.yml     |  40 +++
 .../vnd_datacite_datacite_json/link.yml       |  38 +++
 .../vnd_datacite_datacite_json/redirect.yml   | 232 ++++++++++++++++++
 .../vnd_datacite_datacite_xml/header.yml      |  38 +++
 .../vnd_datacite_datacite_xml/link.yml        |  40 +++
 .../vnd_datacite_datacite_xml/redirect.yml    | 232 ++++++++++++++++++
 .../vnd_schemaorg_ld_json/header.yml          |  40 +++
 .../vnd_schemaorg_ld_json/link.yml            |  38 +++
 .../vnd_schemaorg_ld_json/redirect.yml        | 232 ++++++++++++++++++
 .../application/x-bibtex/header.yml           |  40 +++
 .../application/x-bibtex/link.yml             |  40 +++
 .../application/x-bibtex/redirect.yml         | 232 ++++++++++++++++++
 .../x-research-info-systems/header.yml        |  38 +++
 .../x-research-info-systems/link.yml          |  40 +++
 .../x-research-info-systems/redirect.yml      | 232 ++++++++++++++++++
 spec/heartbeat_spec.rb                        |  10 +
 spec/helpers_spec.rb                          |  89 +++++++
 spec/spec_helper.rb                           |  60 +++++
 vendor/docker/00_app_env.conf                 |   2 +
 vendor/docker/cors.conf                       |   3 +
 vendor/docker/ntp.conf                        |   4 +
 vendor/docker/webapp.conf                     |  10 +
 45 files changed, 3036 insertions(+), 2 deletions(-)
 create mode 100644 .env
 create mode 100644 .travis.yml
 create mode 100644 CHANGELOG.md
 create mode 100644 Dockerfile
 create mode 100644 Gemfile
 create mode 100644 Gemfile.lock
 create mode 100644 app.rb
 create mode 100644 config.ru
 create mode 100644 docker-compose.yml
 create mode 100644 lib/content_negotiation.rb
 create mode 100644 lib/helpers.rb
 create mode 100644 spec/api_spec.rb
 create mode 100644 spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/absent.yml
 create mode 100644 spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/present.yml
 create mode 100644 spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/available_content_type.yml
 create mode 100644 spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/registered_content_type.yml
 create mode 100644 spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/unsupported_content_type.yml
 create mode 100644 spec/fixtures/vcr_cassettes/Helpers/should_pass_thru/doi.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_citationstyles_csl_json/header.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_citationstyles_csl_json/link.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_citationstyles_csl_json/redirect.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/header.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/link.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/redirect.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/header.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/link.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/redirect.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/header.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/link.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/redirect.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/x-bibtex/header.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/x-bibtex/link.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/x-bibtex/redirect.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/x-research-info-systems/header.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/x-research-info-systems/link.yml
 create mode 100644 spec/fixtures/vcr_cassettes/content_negotiation/application/x-research-info-systems/redirect.yml
 create mode 100644 spec/heartbeat_spec.rb
 create mode 100644 spec/helpers_spec.rb
 create mode 100644 spec/spec_helper.rb
 create mode 100644 vendor/docker/00_app_env.conf
 create mode 100644 vendor/docker/cors.conf
 create mode 100644 vendor/docker/ntp.conf
 create mode 100644 vendor/docker/webapp.conf

diff --git a/.env b/.env
new file mode 100644
index 0000000..88e07db
--- /dev/null
+++ b/.env
@@ -0,0 +1,4 @@
+TRUSTED_IP=127.0.0.1
+SEARCH_URL=https://search.datacite.org/
+CITEPROC_URL=https://citation.datacite.org/format
+LOG_LEVEL=debug
diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 0000000..0d5442a
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,14 @@
+language: ruby
+rvm:
+- 2.3.3
+
+addons:
+  code_climate:
+    repo_token: $CODECLIMATE_REPO_TOKEN
+
+install:
+- travis_retry bundle install
+
+script:
+- bundle exec rspec
+- bundle exec codeclimate-test-reporter
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..e69de29
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..a79d31f
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,45 @@
+FROM phusion/passenger-full:0.9.20
+MAINTAINER Martin Fenner "mfenner@datacite.org"
+
+# Set correct environment variables.
+ENV HOME /home/app
+
+# Allow app user to read /etc/container_environment
+RUN usermod -a -G docker_env app
+
+# Use baseimage-docker's init process.
+CMD ["/sbin/my_init"]
+
+# Install Ruby 2.3.3
+RUN bash -lc 'rvm --default use ruby-2.3.3'
+
+# Update installed APT packages
+RUN apt-get update && apt-get upgrade -y -o Dpkg::Options::="--force-confold" && \
+    apt-get install ntp -y && \
+    apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+
+# Enable Passenger and Nginx and remove the default site
+# Preserve env variables for nginx
+RUN rm -f /etc/service/nginx/down && \
+    rm /etc/nginx/sites-enabled/default
+COPY vendor/docker/webapp.conf /etc/nginx/sites-enabled/webapp.conf
+COPY vendor/docker/00_app_env.conf /etc/nginx/conf.d/00_app_env.conf
+COPY vendor/docker/cors.conf /etc/nginx/conf.d/cors.conf
+
+# Use Amazon NTP servers
+COPY vendor/docker/ntp.conf /etc/ntp.conf
+
+# Copy webapp folder
+COPY . /home/app/webapp/
+RUN mkdir -p /home/app/webapp/vendor/bundle && \
+    chown -R app:app /home/app/webapp && \
+    chmod -R 755 /home/app/webapp
+
+# Install Ruby gems
+WORKDIR /home/app/webapp
+RUN gem update --system && \
+    gem install bundler && \
+    /sbin/setuser app bundle install --path vendor/bundle
+
+# Expose web
+EXPOSE 80
diff --git a/Gemfile b/Gemfile
new file mode 100644
index 0000000..46b8c33
--- /dev/null
+++ b/Gemfile
@@ -0,0 +1,30 @@
+source 'http://rubygems.org'
+
+gem 'dotenv'
+gem 'bugsnag'
+gem 'awesome_print'
+gem 'activesupport'
+gem 'sinatra'
+gem 'sinatra-contrib'
+gem 'multi_json'
+gem 'json', '~> 1.8', '>= 1.8.5'
+gem 'oj', '~> 2.18', '>= 2.18.1'
+gem 'iso8601', '~> 0.9.0'
+gem 'maremma', '~> 3.0'
+gem 'bolognese', '~> 0.8.5'
+gem 'nokogiri', '~> 1.6.8'
+
+group :development do
+  gem "better_errors"
+  gem "binding_of_caller"
+  gem 'thin', '~> 1.7'
+end
+
+group :test do
+  gem 'rspec'
+  gem 'capybara'
+  gem 'webmock', '~> 1.20.0'
+  gem 'vcr', '~> 3.0.3'
+  gem 'codeclimate-test-reporter', '~> 1.0.0'
+  gem 'simplecov'
+end
diff --git a/Gemfile.lock b/Gemfile.lock
new file mode 100644
index 0000000..7bceed9
--- /dev/null
+++ b/Gemfile.lock
@@ -0,0 +1,175 @@
+GEM
+  remote: http://rubygems.org/
+  specs:
+    activesupport (4.2.8)
+      i18n (~> 0.7)
+      minitest (~> 5.1)
+      thread_safe (~> 0.3, >= 0.3.4)
+      tzinfo (~> 1.1)
+    addressable (2.5.1)
+      public_suffix (~> 2.0, >= 2.0.2)
+    awesome_print (1.7.0)
+    backports (3.7.0)
+    better_errors (2.1.1)
+      coderay (>= 1.0.0)
+      erubis (>= 2.6.6)
+      rack (>= 0.9.0)
+    bibtex-ruby (4.4.3)
+      latex-decode (~> 0.0)
+    binding_of_caller (0.7.2)
+      debug_inspector (>= 0.0.1)
+    bolognese (0.8.14)
+      activesupport (~> 4.2, >= 4.2.5)
+      bibtex-ruby (~> 4.1)
+      builder (~> 3.2, >= 3.2.2)
+      colorize (~> 0.8.1)
+      loofah (~> 2.0, >= 2.0.3)
+      maremma (~> 3.5)
+      namae (~> 0.10.2)
+      nokogiri (~> 1.6, >= 1.6.8)
+      postrank-uri (~> 1.0, >= 1.0.18)
+      thor (~> 0.19)
+    bugsnag (5.3.0)
+    builder (3.2.3)
+    capybara (2.13.0)
+      addressable
+      mime-types (>= 1.16)
+      nokogiri (>= 1.3.3)
+      rack (>= 1.0.0)
+      rack-test (>= 0.5.4)
+      xpath (~> 2.0)
+    codeclimate-test-reporter (1.0.8)
+      simplecov (<= 0.13)
+    coderay (1.1.1)
+    colorize (0.8.1)
+    crack (0.4.3)
+      safe_yaml (~> 1.0.0)
+    daemons (1.2.4)
+    debug_inspector (0.0.2)
+    diff-lcs (1.3)
+    docile (1.1.5)
+    dotenv (2.2.0)
+    erubis (2.7.0)
+    eventmachine (1.2.3)
+    excon (0.45.4)
+    faraday (0.9.2)
+      multipart-post (>= 1.2, < 3)
+    faraday-encoding (0.0.4)
+      faraday
+    faraday_middleware (0.10.1)
+      faraday (>= 0.7.4, < 1.0)
+    i18n (0.8.1)
+    iso8601 (0.9.1)
+    json (1.8.6)
+    latex-decode (0.2.2)
+      unicode (~> 0.4)
+    loofah (2.0.3)
+      nokogiri (>= 1.5.9)
+    maremma (3.5.6)
+      activesupport (~> 4.2, >= 4.2.5)
+      addressable (>= 2.3.6)
+      builder (~> 3.2, >= 3.2.2)
+      excon (~> 0.45.0)
+      faraday (~> 0.9.2)
+      faraday-encoding (~> 0.0.1)
+      faraday_middleware (~> 0.10.0)
+      multi_json (~> 1.11.2)
+      nokogiri (~> 1.6, >= 1.6.8)
+      oj (~> 2.18, >= 2.18.1)
+    mime-types (3.1)
+      mime-types-data (~> 3.2015)
+    mime-types-data (3.2016.0521)
+    mini_portile2 (2.1.0)
+    minitest (5.10.1)
+    multi_json (1.11.3)
+    multipart-post (2.0.0)
+    namae (0.10.2)
+    nokogiri (1.6.8.1)
+      mini_portile2 (~> 2.1.0)
+    oj (2.18.5)
+    postrank-uri (1.0.22)
+      addressable (>= 2.3.0, < 2.6)
+      nokogiri (>= 1.6.1, < 1.8)
+      public_suffix (>= 2.0.0, < 2.1)
+    public_suffix (2.0.5)
+    rack (1.6.5)
+    rack-protection (1.5.3)
+      rack
+    rack-test (0.6.3)
+      rack (>= 1.0)
+    rspec (3.5.0)
+      rspec-core (~> 3.5.0)
+      rspec-expectations (~> 3.5.0)
+      rspec-mocks (~> 3.5.0)
+    rspec-core (3.5.4)
+      rspec-support (~> 3.5.0)
+    rspec-expectations (3.5.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.5.0)
+    rspec-mocks (3.5.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.5.0)
+    rspec-support (3.5.0)
+    safe_yaml (1.0.4)
+    simplecov (0.13.0)
+      docile (~> 1.1.0)
+      json (>= 1.8, < 3)
+      simplecov-html (~> 0.10.0)
+    simplecov-html (0.10.0)
+    sinatra (1.4.8)
+      rack (~> 1.5)
+      rack-protection (~> 1.4)
+      tilt (>= 1.3, < 3)
+    sinatra-contrib (1.4.7)
+      backports (>= 2.0)
+      multi_json
+      rack-protection
+      rack-test
+      sinatra (~> 1.4.0)
+      tilt (>= 1.3, < 3)
+    thin (1.7.0)
+      daemons (~> 1.0, >= 1.0.9)
+      eventmachine (~> 1.0, >= 1.0.4)
+      rack (>= 1, < 3)
+    thor (0.19.4)
+    thread_safe (0.3.6)
+    tilt (2.0.7)
+    tzinfo (1.2.3)
+      thread_safe (~> 0.1)
+    unicode (0.4.4.4)
+    vcr (3.0.3)
+    webmock (1.20.4)
+      addressable (>= 2.3.6)
+      crack (>= 0.3.2)
+    xpath (2.0.0)
+      nokogiri (~> 1.3)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  activesupport
+  awesome_print
+  better_errors
+  binding_of_caller
+  bolognese (~> 0.8.5)
+  bugsnag
+  capybara
+  codeclimate-test-reporter (~> 1.0.0)
+  dotenv
+  iso8601 (~> 0.9.0)
+  json (~> 1.8, >= 1.8.5)
+  maremma (~> 3.0)
+  multi_json
+  nokogiri (~> 1.6.8)
+  oj (~> 2.18, >= 2.18.1)
+  rspec
+  simplecov
+  sinatra
+  sinatra-contrib
+  thin (~> 1.7)
+  vcr (~> 3.0.3)
+  webmock (~> 1.20.0)
+
+BUNDLED WITH
+   1.12.5
diff --git a/LICENSE b/LICENSE
index 87a03af..2e4df08 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2017 crosscite
+Copyright (c) 2017 DataCite
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index 8f0bf4e..6dc1565 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,3 @@
-# content-resolver
\ No newline at end of file
+# content-resolver
+
+[![Build Status](https://travis-ci.org/crosscite/content-negotiation.svg?branch=master)](https://travis-ci.org/crosscite/content-negotiation)
diff --git a/app.rb b/app.rb
new file mode 100644
index 0000000..c355b19
--- /dev/null
+++ b/app.rb
@@ -0,0 +1,161 @@
+# # load ENV variables from .env file if it exists
+env_file =  File.expand_path("../.env", __FILE__)
+if File.exist?(env_file)
+  require 'dotenv'
+  Dotenv.load! env_file
+end
+
+# load ENV variables from container environment if json file exists
+# see https://github.com/phusion/baseimage-docker#envvar_dumps
+env_json_file = "/etc/container_environment.json"
+if File.exist?(env_json_file)
+  env_vars = JSON.parse(File.read(env_json_file))
+  env_vars.each { |k, v| ENV[k] = v }
+end
+
+require 'active_support/all'
+
+# required ENV variables, can be set in .env file
+ENV['APPLICATION'] ||= "content-negotiation"
+ENV['SITE_TITLE'] ||= "DataCite Content Resolver"
+ENV['LOG_LEVEL'] ||= "info"
+ENV['API_URL'] ||= "https://api.datacite.org"
+ENV['SEARCH_URL'] ||= "https://search.datacite.org"
+
+env_vars = %w(SITE_TITLE LOG_LEVEL API_URL)
+env_vars.each { |env| fail ArgumentError,  "ENV[#{env}] is not set" unless ENV[env].present? }
+
+require 'sinatra'
+require 'sinatra/json'
+require 'sinatra/contrib'
+require 'sinatra/config_file'
+require 'cgi'
+require 'maremma'
+require 'bolognese'
+require 'open-uri'
+require 'uri'
+require 'better_errors'
+
+Dir[File.join(File.dirname(__FILE__), 'lib', '*.rb')].each { |f| require f }
+
+LOG_LEVELS = {
+  "debug" => ::Logger::DEBUG,
+  "info" => ::Logger::INFO,
+  "warn" => ::Logger::WARN,
+}
+
+configure do
+  set :app_file, __FILE__
+
+  # Work around rack protection referrer bug
+  set :protection, except: :json_csrf
+
+  # Set log level
+  set :logging, LOG_LEVELS[ENV['LOG_LEVEL']]
+
+  # include bolognese utility methods
+  include Bolognese::Utils
+  include Bolognese::DoiUtils
+
+  # optionally use Bugsnag for error tracking
+  if ENV['BUGSNAG_KEY']
+    require 'bugsnag'
+    Bugsnag.configure do |config|
+      config.api_key = ENV['BUGSNAG_KEY']
+      config.project_root = settings.root
+      config.app_version = App::VERSION
+      config.release_stage = ENV['RACK_ENV']
+      config.notify_release_stages = %w(production stage development)
+    end
+
+    use Bugsnag::Rack
+    enable :raise_errors
+  end
+end
+
+configure :development do
+  use BetterErrors::Middleware
+  BetterErrors::Middleware.allow_ip! ENV['TRUSTED_IP']
+  BetterErrors.application_root = File.expand_path('..', __FILE__)
+
+  enable :raise_errors, :dump_errors
+  # disable :show_exceptions
+end
+
+after do
+  response.headers['Access-Control-Allow-Origin'] = '*'
+end
+
+get '/heartbeat' do
+  content_type 'text/html'
+
+  'OK'
+end
+
+# return content in one of the formats supported by bolognese gem
+get %r{/content/([^/]+/[^/]+)/(.+)} do
+  # id can be DOI or DOI expressed as URL
+  id = Bolognese::Utils.normalize_id(params[:captures].last)
+  halt 404, "#{params[:captures].last} not found" unless id.present?
+
+  # from is DOI registration agency name
+  from = Bolognese::Utils.find_from_format(id: id)
+
+  content_type = params[:captures].first
+  to = available_content_types[content_type]
+  halt 404, "content for #{content_type} not supported" unless to.present?
+
+  logger.info "#{id} as #{content_type}"
+
+  content_type content_type
+
+  # generate metadata
+  generate(id: id, from: from, to: to)
+end
+
+# legacy support for link-based text/html
+# text/html in accept header is handled by handle proxy
+get %r{/text/html/(.+)} do
+  # id can be DOI or DOI expressed as URL
+  id = Bolognese::Utils.normalize_id(params[:captures].first)
+  halt 404, "#{params[:captures].first} not found" unless id.present?
+
+  url = ENV['SEARCH_URL'] + "works/" + doi_from_url(id)
+  logger.info "#{id} as text/html"
+
+  content_type "text/html"
+
+  redirect url, 303
+end
+
+# link-based content type
+get %r{/([^/]+/[^/]+)/(.+)} do
+  # id can be DOI or DOI expressed as URL
+  id = Bolognese::Utils.normalize_id(params[:captures].last)
+  halt 404, "#{params[:captures].last} not found" unless id.present?
+
+  accept_header = [params[:captures].first]
+  url = redirect_by_content_type(id: id, accept_header: accept_header)
+
+  logger.info "#{id} as #{accept_header.first}"
+
+  content_type accept_header.first
+
+  redirect url, 303
+end
+
+# content type via accept header
+get %r{/(.+)} do
+  # id can be DOI or DOI expressed as URL
+  id = Bolognese::Utils.normalize_id(params[:captures].first)
+  halt 404, "#{params[:captures].first} not found" unless id.present?
+
+  accept_header = request.accept.map { |a| a.to_s }
+  url = redirect_by_content_type(id: id, accept_header: accept_header)
+
+  logger.info "#{id} as #{accept_header.first}"
+
+  content_type accept_header.first
+
+  redirect url, 303
+end
diff --git a/config.ru b/config.ru
new file mode 100644
index 0000000..7e4e031
--- /dev/null
+++ b/config.ru
@@ -0,0 +1,9 @@
+Encoding.default_external = Encoding::UTF_8
+
+require 'rubygems'
+require 'bundler'
+
+Bundler.require
+require './app'
+
+run Sinatra::Application
diff --git a/docker-compose.yml b/docker-compose.yml
new file mode 100644
index 0000000..b4d1dec
--- /dev/null
+++ b/docker-compose.yml
@@ -0,0 +1,13 @@
+version: '2'
+
+services:
+  content-negotiation:
+    env_file:
+      - .env
+    image: crosscite/content-negotiation
+    build: .
+    ports:
+      - "8080:80"
+    volumes:
+      - ./spec:/home/app/webapp/spec
+      - ./app:/home/app/webapp/app
diff --git a/lib/content_negotiation.rb b/lib/content_negotiation.rb
new file mode 100644
index 0000000..11496cf
--- /dev/null
+++ b/lib/content_negotiation.rb
@@ -0,0 +1,7 @@
+require 'sinatra/base'
+require_relative 'helpers'
+
+# convenience class for testing
+class ContentNegotiation
+  include Sinatra::Helpers
+end
diff --git a/lib/helpers.rb b/lib/helpers.rb
new file mode 100644
index 0000000..2860a76
--- /dev/null
+++ b/lib/helpers.rb
@@ -0,0 +1,101 @@
+module Sinatra
+  module Helpers
+    def normalize_id(id)
+      Bolognese::Utils.normalize_id(id)
+    end
+
+    def doi_from_url(id)
+      Bolognese::DoiUtils.doi_from_url(id)
+    end
+
+    def validate_doi(id)
+      Bolognese::DoiUtils.validate_doi(id)
+    end
+
+    def generate(id: nil, from: nil, to: nil)
+      Bolognese::Utils.generate(id: id, from: from, to: to)
+    end
+
+    # determine content-type for the response, in that order:
+    # 1. content-type registered for DOI
+    # 2. content-type available in content negotiation
+    # 3. formatted citation via DOI formatter service
+    # 4. no content-type found, pass through to URL registered in handle system
+    # then redirect based on content_type
+    def redirect_by_content_type(id: nil, accept_header: nil)
+      should_redirect_registered(id: id, accept_header: accept_header) ||
+      should_redirect_available(id: id, accept_header: accept_header) ||
+      should_redirect_citation(id: nil, accept_header: nil) ||
+      should_pass_thru(id: id)
+    end
+
+    def should_redirect_registered(id: nil, accept_header: nil)
+      registered_content_types = get_registered_content_types(id)
+
+      content_type = (accept_header & registered_content_types.keys).first
+      registered_content_types[content_type]
+    end
+
+    def should_redirect_citation(id: nil, accept_header: nil)
+      content_type = accept_header.find { |i| i.start_with?("text/x-bibliography") }
+      return nil unless content_type.present?
+
+      hsh = content_type.split("; ").reduce({}) do |sum, i|
+        k, v = i.split("=")
+        sum[k] = v if v.present?
+        sum
+      end
+
+      params = { doi: doi_from_url(id),
+                 style: hsh["style"] || "apa",
+                 locale: hsh["locale"] || "en-US" }
+
+      ENV['CITEPROC_URL'] + "?" + URI.encode_www_form(params)
+    end
+
+    def should_redirect_available(id: nil, accept_header: nil)
+      content_type = (accept_header & available_content_types.keys).first
+      return nil unless content_type.present?
+
+      "/content/" + content_type + "/" + doi_from_url(id)
+    end
+
+    def should_pass_thru(id: nil)
+      return nil unless validate_doi(id)
+
+      response = Maremma.head id, limit: 0
+      response.headers["location"]
+    end
+
+    # content-types registered for that DOI
+    def get_registered_content_types(id)
+      doi = doi_from_url(id)
+      media_url = ENV['SEARCH_URL'] + "api?q=doi:#{doi}&fl=doi,media&wt=json"
+      response = Maremma.get media_url
+      doc = response.body.dig("data", "response", "docs").first
+      if doc.present?
+        doc.fetch("media", []).reduce({}) do|sum, i|
+          content_type, url = i.split(":", 2)
+          sum[content_type] = url
+          sum
+        end
+      else
+        {}
+      end
+    end
+
+    # content-types supported by bolognese gem
+    def available_content_types
+      {
+        'application/vnd.datacite.datacite+xml' => 'datacite',
+        'application/vnd.datacite.datacite+json' => 'datacite_json',
+        'application/vnd.schemaorg.ld+json' => 'schema_org',
+        'application/vnd.citationstyles.csl+json' => 'citeproc',
+        'application/x-research-info-systems' => 'ris',
+        'application/x-bibtex' => 'bibtex'
+      }
+    end
+  end
+end
+
+Sinatra::Application.helpers Sinatra::Helpers
diff --git a/spec/api_spec.rb b/spec/api_spec.rb
new file mode 100644
index 0000000..d2a915f
--- /dev/null
+++ b/spec/api_spec.rb
@@ -0,0 +1,164 @@
+require 'spec_helper'
+
+describe 'content negotiation', vcr: true do
+  context "application/vnd.datacite.datacite+xml" do
+    it "header" do
+      get '/10.5061/dryad.8515', nil, { "HTTP_ACCEPT" => "application/vnd.datacite.datacite+xml" }
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.datacite.datacite+xml/10.5061/dryad.8515")
+    end
+
+    it "link" do
+      get '/application/vnd.datacite.datacite+xml/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.datacite.datacite+xml/10.5061/dryad.8515")
+    end
+
+    it "redirect" do
+      get '/content/application/vnd.datacite.datacite+xml/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq("http://example.org/content/application/vnd.datacite.datacite+xml/10.5061/dryad.8515")
+    end
+  end
+
+  context "application/vnd.datacite.datacite+xml" do
+    it "header" do
+      get '/10.5061/dryad.8515', nil, { "HTTP_ACCEPT" => "application/vnd.datacite.datacite+xml" }
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.datacite.datacite+xml/10.5061/dryad.8515")
+    end
+
+    it "link" do
+      get '/application/vnd.datacite.datacite+xml/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.datacite.datacite+xml/10.5061/dryad.8515")
+    end
+
+    it "redirect" do
+      get '/content/application/vnd.datacite.datacite+xml/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq("")
+    end
+  end
+
+  context "application/vnd.datacite.datacite+json" do
+    it "header" do
+      get '/10.5061/dryad.8515', nil, { "HTTP_ACCEPT" => "application/vnd.datacite.datacite+json" }
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.datacite.datacite+json/10.5061/dryad.8515")
+    end
+
+    it "link" do
+      get '/application/vnd.datacite.datacite+json/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.datacite.datacite+json/10.5061/dryad.8515")
+    end
+
+    it "redirect" do
+      get '/content/application/vnd.datacite.datacite+json/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq("")
+    end
+  end
+
+  context "application/vnd.schemaorg.ld+json" do
+    it "header" do
+      get '/10.5061/dryad.8515', nil, { "HTTP_ACCEPT" => "application/vnd.schemaorg.ld+json" }
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.schemaorg.ld+json/10.5061/dryad.8515")
+    end
+
+    it "link" do
+      get '/application/vnd.schemaorg.ld+json/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.schemaorg.ld+json/10.5061/dryad.8515")
+    end
+
+    it "redirect" do
+      get '/content/application/vnd.schemaorg.ld+json/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq("")
+    end
+  end
+
+  context "application/vnd.citationstyles.csl+json" do
+    it "header" do
+      get '/10.5061/dryad.8515', nil, { "HTTP_ACCEPT" => "application/vnd.citationstyles.csl+json" }
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.citationstyles.csl+json/10.5061/dryad.8515")
+    end
+
+    it "link" do
+      get '/application/vnd.citationstyles.csl+json/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/vnd.citationstyles.csl+json/10.5061/dryad.8515")
+    end
+
+    it "redirect" do
+      get '/content/application/vnd.citationstyles.csl+json/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq("")
+    end
+  end
+
+  context "application/x-research-info-systems" do
+    it "header" do
+      get '/10.5061/dryad.8515', nil, { "HTTP_ACCEPT" => "application/x-research-info-systems" }
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/x-research-info-systems/10.5061/dryad.8515")
+    end
+
+    it "link" do
+      get '/application/x-research-info-systems/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/x-research-info-systems/10.5061/dryad.8515")
+    end
+
+    it "redirect" do
+      get '/content/application/x-research-info-systems/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq("")
+    end
+  end
+
+  context "application/x-bibtex" do
+    it "header" do
+      get '/10.5061/dryad.8515', nil, { "HTTP_ACCEPT" => "application/x-bibtex" }
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/x-bibtex/10.5061/dryad.8515")
+    end
+
+    it "link" do
+      get '/application/x-bibtex/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(303)
+      expect(last_response.headers["Location"]).to eq("http://example.org/content/application/x-bibtex/10.5061/dryad.8515")
+    end
+
+    it "redirect" do
+      get '/content/application/x-bibtex/10.5061/dryad.8515'
+
+      expect(last_response.status).to eq(200)
+      expect(last_response.body).to eq("")
+    end
+  end
+end
diff --git a/spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/absent.yml b/spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/absent.yml
new file mode 100644
index 0000000..6153f6c
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/absent.yml
@@ -0,0 +1,40 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5061/dryad.8515&wt=json
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - text/html,application/json,application/xml;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5
+  response:
+    status:
+      code: 200
+      message: ''
+    headers:
+      Access-Control-Allow-Methods:
+      - GET, POST, OPTIONS
+      Access-Control-Allow-Origin:
+      - "*"
+      Content-Type:
+      - application/json;charset=UTF-8
+      Date:
+      - Wed, 12 Apr 2017 13:22:09 GMT
+      Server:
+      - openresty/1.11.2.2
+      Content-Length:
+      - '116'
+      Connection:
+      - keep-alive
+    body:
+      encoding: UTF-8
+      string: '{"responseHeader":{"status":0,"QTime":6},"response":{"numFound":1,"start":0,"docs":[{"doi":"10.5061/DRYAD.8515"}]}}
+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:09 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/present.yml b/spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/present.yml
new file mode 100644
index 0000000..c670cc1
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/Helpers/get_registered_content_types/present.yml
@@ -0,0 +1,40 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5284/1015681&wt=json
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - text/html,application/json,application/xml;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5
+  response:
+    status:
+      code: 200
+      message: ''
+    headers:
+      Access-Control-Allow-Methods:
+      - GET, POST, OPTIONS
+      Access-Control-Allow-Origin:
+      - "*"
+      Content-Type:
+      - application/json;charset=UTF-8
+      Date:
+      - Wed, 12 Apr 2017 13:22:10 GMT
+      Server:
+      - openresty/1.11.2.2
+      Content-Length:
+      - '282'
+      Connection:
+      - keep-alive
+    body:
+      encoding: UTF-8
+      string: '{"responseHeader":{"status":0,"QTime":6},"response":{"numFound":1,"start":0,"docs":[{"doi":"10.5284/1015681","media":["application/pdf:http://archaeologydataservice.ac.uk/catalogue/adsdata/arch-1045-1/dissemination/pdf/356_ThewatertreatmentplantSaltersfordGrantham_Little.pdf"]}]}}
+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:10 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/available_content_type.yml b/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/available_content_type.yml
new file mode 100644
index 0000000..970d46a
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/available_content_type.yml
@@ -0,0 +1,38 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5438/0000-0c2g&wt=json
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - text/html,application/json,application/xml;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5
+  response:
+    status:
+      code: 200
+      message: ''
+    headers:
+      Access-Control-Allow-Methods:
+      - GET, POST, OPTIONS
+      Access-Control-Allow-Origin:
+      - "*"
+      Content-Type:
+      - application/json;charset=UTF-8
+      Date:
+      - Wed, 12 Apr 2017 13:22:11 GMT
+      Server:
+      - openresty/1.11.2.2
+      Connection:
+      - keep-alive
+    body:
+      encoding: UTF-8
+      string: '{"responseHeader":{"status":0,"QTime":3},"response":{"numFound":1,"start":0,"docs":[{"doi":"10.5438/0000-0C2G","media":["application/xml:https://blog.datacite.org/oi-project-underway-for-open-org-id-registry/oi-project-underway-for-open-org-id-registry.xml"]}]}}
+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:10 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/registered_content_type.yml b/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/registered_content_type.yml
new file mode 100644
index 0000000..1c8fce4
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/registered_content_type.yml
@@ -0,0 +1,40 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5284/1015681&wt=json
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - text/html,application/json,application/xml;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5
+  response:
+    status:
+      code: 200
+      message: ''
+    headers:
+      Access-Control-Allow-Methods:
+      - GET, POST, OPTIONS
+      Access-Control-Allow-Origin:
+      - "*"
+      Content-Type:
+      - application/json;charset=UTF-8
+      Date:
+      - Wed, 12 Apr 2017 13:22:10 GMT
+      Server:
+      - openresty/1.11.2.2
+      Content-Length:
+      - '282'
+      Connection:
+      - keep-alive
+    body:
+      encoding: UTF-8
+      string: '{"responseHeader":{"status":0,"QTime":0},"response":{"numFound":1,"start":0,"docs":[{"doi":"10.5284/1015681","media":["application/pdf:http://archaeologydataservice.ac.uk/catalogue/adsdata/arch-1045-1/dissemination/pdf/356_ThewatertreatmentplantSaltersfordGrantham_Little.pdf"]}]}}
+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:10 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/unsupported_content_type.yml b/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/unsupported_content_type.yml
new file mode 100644
index 0000000..d7f472f
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/Helpers/redirect_by_content_type/unsupported_content_type.yml
@@ -0,0 +1,73 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5438/0000-0c2g&wt=json
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - text/html,application/json,application/xml;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5
+  response:
+    status:
+      code: 200
+      message: ''
+    headers:
+      Access-Control-Allow-Methods:
+      - GET, POST, OPTIONS
+      Access-Control-Allow-Origin:
+      - "*"
+      Content-Type:
+      - application/json;charset=UTF-8
+      Date:
+      - Wed, 12 Apr 2017 13:22:11 GMT
+      Server:
+      - openresty/1.11.2.2
+      Connection:
+      - keep-alive
+    body:
+      encoding: UTF-8
+      string: '{"responseHeader":{"status":0,"QTime":1},"response":{"numFound":1,"start":0,"docs":[{"doi":"10.5438/0000-0C2G","media":["application/xml:https://blog.datacite.org/oi-project-underway-for-open-org-id-registry/oi-project-underway-for-open-org-id-registry.xml"]}]}}
+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:11 GMT
+- request:
+    method: head
+    uri: https://doi.org/10.5438/0000-0C2G
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - text/html,application/json,application/xml;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5
+  response:
+    status:
+      code: 303
+      message: ''
+    headers:
+      Server:
+      - Apache-Coyote/1.1
+      Vary:
+      - Accept
+      Location:
+      - https://blog.datacite.org/oi-project-underway-for-open-org-id-registry/
+      Expires:
+      - Wed, 12 Apr 2017 13:23:04 GMT
+      Content-Type:
+      - text/html;charset=utf-8
+      Content-Length:
+      - '227'
+      Date:
+      - Wed, 12 Apr 2017 13:22:10 GMT
+    body:
+      encoding: UTF-8
+      string: ''
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:11 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/Helpers/should_pass_thru/doi.yml b/spec/fixtures/vcr_cassettes/Helpers/should_pass_thru/doi.yml
new file mode 100644
index 0000000..c453567
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/Helpers/should_pass_thru/doi.yml
@@ -0,0 +1,38 @@
+---
+http_interactions:
+- request:
+    method: head
+    uri: https://doi.org/10.5284/1015681
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - text/html,application/json,application/xml;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5
+  response:
+    status:
+      code: 303
+      message: ''
+    headers:
+      Server:
+      - Apache-Coyote/1.1
+      Vary:
+      - Accept
+      Location:
+      - http://archaeologydataservice.ac.uk/archives/view/greylit/details.cfm?id=13979
+      Expires:
+      - Wed, 12 Apr 2017 13:23:04 GMT
+      Content-Type:
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--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_citationstyles_csl_json/link.yml
@@ -0,0 +1,40 @@
+---
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--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_citationstyles_csl_json/redirect.yml
@@ -0,0 +1,232 @@
+---
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+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/header.yml
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diff --git a/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/link.yml b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/link.yml
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--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/link.yml
@@ -0,0 +1,38 @@
+---
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+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_json/redirect.yml
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new file mode 100644
index 0000000..1faea4a
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/header.yml
@@ -0,0 +1,38 @@
+---
+http_interactions:
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+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5061/dryad.8515&wt=json
+    body:
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+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:14 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/link.yml b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/link.yml
new file mode 100644
index 0000000..b6b34e8
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/link.yml
@@ -0,0 +1,40 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5061/dryad.8515&wt=json
+    body:
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+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:14 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/redirect.yml b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/redirect.yml
new file mode 100644
index 0000000..7be7e89
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_datacite_datacite_xml/redirect.yml
@@ -0,0 +1,232 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://api.datacite.org/prefixes/10.5061
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
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+      Accept:
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+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:13 GMT
+- request:
+    method: get
+    uri: https://doi.org/10.5061/dryad.8515
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
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+      Accept:
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+  response:
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+      code: 303
+      message: ''
+    headers:
+      Server:
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+      Date:
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+    body:
+      encoding: UTF-8
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+  recorded_at: Wed, 12 Apr 2017 13:22:14 GMT
+- request:
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diff --git a/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/header.yml b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/header.yml
new file mode 100644
index 0000000..1cb5e7e
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/header.yml
@@ -0,0 +1,40 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5061/dryad.8515&wt=json
+    body:
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+      string: ''
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+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:22 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/link.yml b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/link.yml
new file mode 100644
index 0000000..f537c76
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/link.yml
@@ -0,0 +1,38 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://search.datacite.org/api?fl=doi,media&q=doi:10.5061/dryad.8515&wt=json
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
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+
+'
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:24 GMT
+recorded_with: VCR 3.0.3
diff --git a/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/redirect.yml b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/redirect.yml
new file mode 100644
index 0000000..4714848
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/content_negotiation/application/vnd_schemaorg_ld_json/redirect.yml
@@ -0,0 +1,232 @@
+---
+http_interactions:
+- request:
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+    uri: https://api.datacite.org/prefixes/10.5061
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
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+      Accept:
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+  response:
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+      message: ''
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+      X-Powered-By:
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+      X-Request-Id:
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+      Connection:
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+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:23 GMT
+- request:
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+    uri: https://doi.org/10.5061/dryad.8515
+    body:
+      encoding: US-ASCII
+      string: ''
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+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:23 GMT
+- request:
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+    uri: http://data.datacite.org/10.5061%2Fdryad.8515
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+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - application/vnd.datacite.datacite+xml
+  response:
+    status:
+      code: 303
+      message: ''
+    headers:
+      Server:
+      - Apache-Coyote/1.1
+      Vary:
+      - Accept
+      Location:
+      - http://data.datacite.org/10.5061%2Fdryad.8515
+      Expires:
+      - Wed, 12 Apr 2017 13:23:04 GMT
+      Content-Type:
+      - text/html;charset=utf-8
+      Content-Length:
+      - '175'
+      Date:
+      - Wed, 12 Apr 2017 13:22:15 GMT
+    body:
+      encoding: UTF-8
+      string: |-
+        <html><head><title>Handle Redirect</title></head>
+        <body><a href="http://data.datacite.org/10.5061%2Fdryad.8515">http://data.datacite.org/10.5061%2Fdryad.8515</a></body></html>
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:16 GMT
+- request:
+    method: get
+    uri: http://data.datacite.org/10.5061%2Fdryad.8515
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - application/vnd.datacite.datacite+xml
+  response:
+    status:
+      code: 301
+      message: ''
+    headers:
+      Content-Type:
+      - text/html
+      Date:
+      - Wed, 12 Apr 2017 13:22:16 GMT
+      Location:
+      - https://data.datacite.org/10.5061%2Fdryad.8515
+      Server:
+      - openresty/1.11.2.2
+      Content-Length:
+      - '191'
+      Connection:
+      - keep-alive
+    body:
+      encoding: UTF-8
+      string: "<html>\r\n<head><title>301 Moved Permanently</title></head>\r\n<body
+        bgcolor=\"white\">\r\n<center><h1>301 Moved Permanently</h1></center>\r\n<hr><center>openresty/1.11.2.2</center>\r\n</body>\r\n</html>\r\n"
+    http_version: 
+  recorded_at: Wed, 12 Apr 2017 13:22:16 GMT
+- request:
+    method: get
+    uri: https://data.datacite.org/10.5061%2Fdryad.8515
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      User-Agent:
+      - Maremma - https://github.com/datacite/maremma
+      Accept:
+      - application/vnd.datacite.datacite+xml
+  response:
+    status:
+      code: 200
+      message: ''
+    headers:
+      Access-Control-Allow-Methods:
+      - GET, POST, OPTIONS
+      Access-Control-Allow-Origin:
+      - "*"
+      Cache-Control:
+      - no-transform, max-age=3600
+      Content-Type:
+      - application/vnd.datacite.datacite+xml
+      Date:
+      - Wed, 12 Apr 2017 13:22:16 GMT
+      Last-Modified:
+      - Sat, 04 Feb 2017 17:54:37 GMT
+      Server:
+      - openresty/1.11.2.2
+      Vary:
+      - Accept
+      Content-Length:
+      - '2601'
+      Connection:
+      - keep-alive
+    body:
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+    http_version: 
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+recorded_with: VCR 3.0.3
diff --git a/spec/heartbeat_spec.rb b/spec/heartbeat_spec.rb
new file mode 100644
index 0000000..72c7193
--- /dev/null
+++ b/spec/heartbeat_spec.rb
@@ -0,0 +1,10 @@
+require 'spec_helper'
+
+describe '/heartbeat' do
+  it "get heartbeat" do
+    get '/heartbeat'
+
+    expect(last_response.status).to eq(200)
+    expect(last_response.body).to eq("OK")
+  end
+end
diff --git a/spec/helpers_spec.rb b/spec/helpers_spec.rb
new file mode 100644
index 0000000..e32aa95
--- /dev/null
+++ b/spec/helpers_spec.rb
@@ -0,0 +1,89 @@
+require 'spec_helper'
+
+describe "Helpers", type: :model, vcr: true do
+  let(:fixture_path) { "#{Sinatra::Application.root}/spec/fixtures/" }
+  subject { ContentNegotiation.new }
+
+  context "normalize_id" do
+    it "doi" do
+      id = subject.normalize_id("10.5061/DRYAD.8515")
+      expect(id).to eq("https://doi.org/10.5061/dryad.8515")
+    end
+
+    it "http dx.doi.org" do
+      id = subject.normalize_id("http://dx.doi.org/10.5284/1015681")
+      expect(id).to eq("https://doi.org/10.5284/1015681")
+    end
+  end
+
+  context "doi_from_url" do
+    it "url" do
+      doi = subject.doi_from_url("https://doi.org/10.5061/dryad.8515")
+      expect(doi).to eq("10.5061/dryad.8515")
+    end
+
+    it "doi" do
+      doi = subject.doi_from_url("10.5061/dryad.8515")
+      expect(doi).to eq("10.5061/dryad.8515")
+    end
+
+    it "not a doi" do
+      doi = subject.doi_from_url("https://doi.org/10.5061")
+      expect(doi).to be nil
+    end
+  end
+
+  context "get_registered_content_types" do
+    it "present" do
+      content_types = subject.get_registered_content_types("https://doi.org/10.5284/1015681")
+      expect(content_types).to eq("application/pdf" => "http://archaeologydataservice.ac.uk/catalogue/adsdata/arch-1045-1/dissemination/pdf/356_ThewatertreatmentplantSaltersfordGrantham_Little.pdf")
+    end
+
+    it "absent" do
+      content_types= subject.get_registered_content_types("https://doi.org/10.5061/dryad.8515")
+      expect(content_types).to be_empty
+    end
+  end
+
+  context "redirect_by_content_type" do
+    it "registered content_type" do
+      id = "https://doi.org/10.5284/1015681"
+      accept_header = ["application/pdf"]
+      redirect_url = subject.redirect_by_content_type(id: id, accept_header: accept_header)
+      expect(redirect_url).to eq("http://archaeologydataservice.ac.uk/catalogue/adsdata/arch-1045-1/dissemination/pdf/356_ThewatertreatmentplantSaltersfordGrantham_Little.pdf")
+    end
+
+    it "available content_type" do
+      id = "https://doi.org/10.5438/0000-0C2G"
+      accept_header = ["application/vnd.datacite.datacite+xml"]
+      redirect_url = subject.redirect_by_content_type(id: id, accept_header: accept_header)
+      expect(redirect_url).to eq("/content/application/vnd.datacite.datacite+xml/10.5438/0000-0c2g")
+    end
+
+    it "citation" do
+      id = "https://doi.org/10.5438/0000-0C2G"
+      accept_header = ["text/x-bibliography; style=modern-language-association-8th-edition; locale=fr-FR"]
+      redirect_url = subject.should_redirect_citation(id: id, accept_header: accept_header)
+      expect(redirect_url).to eq("/content/application/vnd.datacite.datacite+xml/10.5438/0000-0c2g")
+    end
+
+    it "unsupported content_type" do
+      id = "https://doi.org/10.5438/0000-0C2G"
+      accept_header = ["application/vnd.crossref.unixref+xml"]
+      redirect_url = subject.redirect_by_content_type(id: id, accept_header: accept_header)
+      expect(redirect_url).to eq("https://blog.datacite.org/oi-project-underway-for-open-org-id-registry/")
+    end
+  end
+
+  context "should_pass_thru" do
+    it "doi" do
+      url = subject.should_pass_thru(id: "https://doi.org/10.5284/1015681")
+      expect(url).to eq("http://archaeologydataservice.ac.uk/archives/view/greylit/details.cfm?id=13979")
+    end
+
+    it "no doi" do
+      url = subject.should_pass_thru(id: "http://archaeologydataservice.ac.uk/archives/view/greylit/details.cfm?id=13979")
+      expect(url).to be nil
+    end
+  end
+end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
new file mode 100644
index 0000000..6b33b1b
--- /dev/null
+++ b/spec/spec_helper.rb
@@ -0,0 +1,60 @@
+ENV['RACK_ENV'] = 'test'
+
+# set up Code Climate
+require 'simplecov'
+SimpleCov.start
+
+require 'sinatra'
+require 'rspec'
+require 'rack/test'
+require 'webmock/rspec'
+require 'vcr'
+
+require File.join(File.dirname(__FILE__), '..', 'app.rb')
+
+# require files in lib folder
+Dir[File.join(File.dirname(__FILE__), '../lib/**/*.rb')].each { |f| require f }
+
+# setup test environment
+set :environment, :test
+set :run, false
+set :raise_errors, true
+set :logging, false
+set :dump_errors, false
+set :show_exceptions, false
+
+def app
+  Sinatra::Application
+end
+
+RSpec.configure do |config|
+  config.include Rack::Test::Methods
+  config.order = :random
+end
+
+WebMock.disable_net_connect!(
+  allow: ['codeclimate.com:443', ENV['PRIVATE_IP'], ENV['HOSTNAME']],
+  allow_localhost: true
+)
+
+VCR.configure do |c|
+  c.cassette_library_dir = 'spec/fixtures/vcr_cassettes'
+  c.hook_into :webmock
+  c.ignore_localhost = true
+  c.ignore_hosts 'codeclimate.com'
+  c.filter_sensitive_data('<ORCID_UPDATE_KEY>') { ENV['ORCID_UPDATE_KEY'] }
+  c.filter_sensitive_data('<ORCID_UPDATE_TOKEN>') { ENV['ORCID_UPDATE_TOKEN'] }
+  c.allow_http_connections_when_no_cassette = false
+  c.configure_rspec_metadata!
+end
+
+def capture_stdout(&block)
+  stdout, string = $stdout, StringIO.new
+  $stdout = string
+
+  yield
+
+  string.tap(&:rewind).read
+ensure
+  $stdout = stdout
+end
diff --git a/vendor/docker/00_app_env.conf b/vendor/docker/00_app_env.conf
new file mode 100644
index 0000000..c4a9494
--- /dev/null
+++ b/vendor/docker/00_app_env.conf
@@ -0,0 +1,2 @@
+# File will be overwritten if user runs the container with `-e PASSENGER_APP_ENV=...`!
+passenger_app_env development;
diff --git a/vendor/docker/cors.conf b/vendor/docker/cors.conf
new file mode 100644
index 0000000..faaeffe
--- /dev/null
+++ b/vendor/docker/cors.conf
@@ -0,0 +1,3 @@
+# enable CORS
+more_set_headers 'Access-Control-Allow-Origin: *';
+more_set_headers 'Access-Control-Allow-Headers: Content-Type,Accept,Accept-Encoding,Origin,User-Agent,Cache-Control,Keep-Alive';
diff --git a/vendor/docker/ntp.conf b/vendor/docker/ntp.conf
new file mode 100644
index 0000000..b075221
--- /dev/null
+++ b/vendor/docker/ntp.conf
@@ -0,0 +1,4 @@
+server 0.amazon.pool.ntp.org iburst
+server 1.amazon.pool.ntp.org iburst
+server 2.amazon.pool.ntp.org iburst
+server 3.amazon.pool.ntp.org iburst
diff --git a/vendor/docker/webapp.conf b/vendor/docker/webapp.conf
new file mode 100644
index 0000000..fb67ac2
--- /dev/null
+++ b/vendor/docker/webapp.conf
@@ -0,0 +1,10 @@
+server {
+    listen 80 default_server;
+    server_name _;
+    root /home/app/webapp/public;
+
+    passenger_enabled on;
+    passenger_user app;
+    passenger_ruby /usr/bin/ruby;
+    merge_slashes off;
+}