Merge branch 'fix/github-importer' into 'master'

Refactoring rake task to import GitHub repositories

See merge request !10695

Gemfile

@@ -17,6 +17,8 @@ gem 'pg', '~> 0.18.2', group: :postgres
 gem 'rugged', '~> 0.25.1.1'
+gem 'faraday', '~> 0.11.0'
+
 # Authentication libraries
 gem 'devise', '~> 4.2'
 gem 'doorkeeper', '~> 4.2.0'
@@ -183,7 +185,7 @@ gem 'gemnasium-gitlab-service', '~> 0.2'
 gem 'slack-notifier', '~> 1.5.1'
 # Asana integration
-gem 'asana', '~> 0.4.0'
+gem 'asana', '~> 0.6.0'
 # FogBugz integration
 gem 'ruby-fogbugz', '~> 0.2.1'
@@ -342,7 +344,7 @@ gem 'html2text'
 gem 'ruby-prof', '~> 0.16.2'
 # OAuth
-gem 'oauth2', '~> 1.2.0'
+gem 'oauth2', '~> 1.3.0'
 # Soft deletion
 gem 'paranoia', '~> 2.2'

Gemfile.lock

@@ -47,7 +47,7 @@ GEM
     akismet (2.0.0)
     allocations (1.0.5)
     arel (6.0.4)
-    asana (0.4.0)
+    asana (0.6.0)
       faraday (~> 0.9)
       faraday_middleware (~> 0.9)
       faraday_middleware-multi_json (~> 0.0)
@@ -193,10 +193,10 @@ GEM
     factory_girl_rails (4.7.0)
       factory_girl (~> 4.7.0)
       railties (>= 3.0.0)
-    faraday (0.9.2)
+    faraday (0.11.0)
       multipart-post (>= 1.2, < 3)
-    faraday_middleware (0.10.0)
-      faraday (>= 0.7.4, < 0.10)
+    faraday_middleware (0.11.0.1)
+      faraday (>= 0.7.4, < 1.0)
     faraday_middleware-multi_json (0.0.6)
       faraday_middleware
       multi_json
@@ -452,15 +452,15 @@ GEM
       mini_portile2 (~> 2.1.0)
     numerizer (0.1.1)
     oauth (0.5.1)
-    oauth2 (1.2.0)
-      faraday (>= 0.8, < 0.10)
+    oauth2 (1.3.1)
+      faraday (>= 0.8, < 0.12)
       jwt (~> 1.0)
       multi_json (~> 1.3)
       multi_xml (~> 0.5)
       rack (>= 1.2, < 3)
     octokit (4.6.2)
       sawyer (~> 0.8.0, >= 0.5.3)
-    oj (2.17.4)
+    oj (2.17.5)
     omniauth (1.4.2)
       hashie (>= 1.2, < 4)
       rack (>= 1.0, < 3)
@@ -851,7 +851,7 @@ DEPENDENCIES
   after_commit_queue (~> 1.3.0)
   akismet (~> 2.0)
   allocations (~> 1.0)
-  asana (~> 0.4.0)
+  asana (~> 0.6.0)
   asciidoctor (~> 1.5.2)
   asciidoctor-plantuml (= 0.0.7)
   attr_encrypted (~> 3.0.0)
@@ -889,6 +889,7 @@ DEPENDENCIES
   email_reply_trimmer (~> 0.1)
   email_spec (~> 1.6.0)
   factory_girl_rails (~> 4.7.0)
+  faraday (~> 0.11.0)
   ffaker (~> 2.4)
   flay (~> 2.8.0)
   fog-aws (~> 0.9)
@@ -940,7 +941,7 @@ DEPENDENCIES
   mysql2 (~> 0.3.16)
   net-ssh (~> 3.0.1)
   nokogiri (~> 1.6.7, >= 1.6.7.2)
-  oauth2 (~> 1.2.0)
+  oauth2 (~> 1.3.0)
   octokit (~> 4.6.2)
   oj (~> 2.17.4)
   omniauth (~> 1.4.2)

lib/github/client.rb

+module Github
+  class Client
+    attr_reader :connection, :rate_limit
+
+    def initialize(options)
+      @connection = Faraday.new(url: options.fetch(:url)) do |faraday|
+        faraday.options.open_timeout = options.fetch(:timeout, 60)
+        faraday.options.timeout = options.fetch(:timeout, 60)
+        faraday.authorization 'token', options.fetch(:token)
+        faraday.adapter :net_http
+      end
+
+      @rate_limit = RateLimit.new(connection)
+    end
+
+    def get(url, query = {})
+      exceed, reset_in = rate_limit.get
+      sleep reset_in if exceed
+
+      Github::Response.new(connection.get(url, query))
+    end
+  end
+end

lib/github/collection.rb

+module Github
+  class Collection
+    attr_reader :options
+
+    def initialize(options)
+      @options = options
+    end
+
+    def fetch(url, query = {})
+      return [] if url.blank?
+
+      Enumerator.new do |yielder|
+        loop do
+          response = client.get(url, query)
+          response.body.each { |item| yielder << item }
+
+          raise StopIteration unless response.rels.key?(:next)
+          url = response.rels[:next]
+        end
+      end.lazy
+    end
+
+    private
+
+    def client
+      @client ||= Github::Client.new(options)
+    end
+  end
+end

lib/github/error.rb

+module Github
+  RepositoryFetchError = Class.new(StandardError)
+end

lib/github/import.rb

+require_relative 'error'
+module Github
+  class Import
+    include Gitlab::ShellAdapter
+
+    class MergeRequest < ::MergeRequest
+      self.table_name = 'merge_requests'
+
+      self.reset_callbacks :save
+      self.reset_callbacks :commit
+      self.reset_callbacks :update
+      self.reset_callbacks :validate
+    end
+
+    class Issue < ::Issue
+      self.table_name = 'issues'
+
+      self.reset_callbacks :save
+      self.reset_callbacks :commit
+      self.reset_callbacks :update
+      self.reset_callbacks :validate
+    end
+
+    class Note < ::Note
+      self.table_name = 'notes'
+
+      self.reset_callbacks :save
+      self.reset_callbacks :commit
+      self.reset_callbacks :update
+      self.reset_callbacks :validate
+    end
+
+    class LegacyDiffNote < ::LegacyDiffNote
+      self.table_name = 'notes'
+
+      self.reset_callbacks :commit
+      self.reset_callbacks :update
+      self.reset_callbacks :validate
+    end
+
+    attr_reader :project, :repository, :repo, :options, :errors, :cached, :verbose
+
+    def initialize(project, options)
+      @project = project
+      @repository = project.repository
+      @repo = project.import_source
+      @options = options
+      @verbose = options.fetch(:verbose, false)
+      @cached  = Hash.new { |hash, key| hash[key] = Hash.new }
+      @errors  = []
+    end
+
+    # rubocop: disable Rails/Output
+    def execute
+      puts 'Fetching repository...'.color(:aqua) if verbose
+      fetch_repository
+      puts 'Fetching labels...'.color(:aqua) if verbose
+      fetch_labels
+      puts 'Fetching milestones...'.color(:aqua) if verbose
+      fetch_milestones
+      puts 'Fetching pull requests...'.color(:aqua) if verbose
+      fetch_pull_requests
+      puts 'Fetching issues...'.color(:aqua) if verbose
+      fetch_issues
+      puts 'Cloning wiki repository...'.color(:aqua) if verbose
+      fetch_wiki_repository
+      puts 'Expiring repository cache...'.color(:aqua) if verbose
+      expire_repository_cache
+
+      true
+    rescue Github::RepositoryFetchError
+      false
+    ensure
+      keep_track_of_errors
+    end
+
+    private
+
+    def fetch_repository
+      begin
+        project.create_repository unless project.repository.exists?
+        project.repository.add_remote('github', "https://{options.fetch(:token)}@github.com/#{repo}.git")
+        project.repository.set_remote_as_mirror('github')
+        project.repository.fetch_remote('github', forced: true)
+      rescue Gitlab::Shell::Error => e
+        error(:project, "https://github.com/#{repo}.git", e.message)
+        raise Github::RepositoryFetchError
+      end
+    end
+
+    def fetch_wiki_repository
+      wiki_url  = "https://{options.fetch(:token)}@github.com/#{repo}.wiki.git"
+      wiki_path = "#{project.path_with_namespace}.wiki"
+
+      unless project.wiki.repository_exists?
+        gitlab_shell.import_repository(project.repository_storage_path, wiki_path, wiki_url)
+      end
+    rescue Gitlab::Shell::Error => e
+      # GitHub error message when the wiki repo has not been created,
+      # this means that repo has wiki enabled, but have no pages. So,
+      # we can skip the import.
+      if e.message !~ /repository not exported/
+        errors(:wiki, wiki_url, e.message)
+      end
+    end
+
+    def fetch_labels
+      url = "/repos/#{repo}/labels"
+
+      while url
+        response = Github::Client.new(options).get(url)
+
+        response.body.each do |raw|
+          begin
+            representation = Github::Representation::Label.new(raw)
+
+            label = project.labels.find_or_create_by!(title: representation.title) do |label|
+              label.color = representation.color
+            end
+
+            cached[:label_ids][label.title] = label.id
+          rescue => e
+            error(:label, representation.url, e.message)
+          end
+        end
+
+        url = response.rels[:next]
+      end
+    end
+
+    def fetch_milestones
+      url = "/repos/#{repo}/milestones"
+
+      while url
+        response = Github::Client.new(options).get(url, state: :all)
+
+        response.body.each do |raw|
+          begin
+            milestone = Github::Representation::Milestone.new(raw)
+            next if project.milestones.where(iid: milestone.iid).exists?
+
+            project.milestones.create!(
+              iid: milestone.iid,
+              title: milestone.title,
+              description: milestone.description,
+              due_date: milestone.due_date,
+              state: milestone.state,
+              created_at: milestone.created_at,
+              updated_at: milestone.updated_at
+            )
+          rescue => e
+            error(:milestone, milestone.url, e.message)
+          end
+        end
+
+        url = response.rels[:next]
+      end
+    end
+
+    def fetch_pull_requests
+      url = "/repos/#{repo}/pulls"
+
+      while url
+        response = Github::Client.new(options).get(url, state: :all, sort: :created, direction: :asc)
+
+        response.body.each do |raw|
+          pull_request  = Github::Representation::PullRequest.new(raw, options.merge(project: project))
+          merge_request = MergeRequest.find_or_initialize_by(iid: pull_request.iid, source_project_id: project.id)
+          next unless merge_request.new_record? && pull_request.valid?
+
+          begin
+            restore_branches(pull_request)
+
+            author_id                       = user_id(pull_request.author, project.creator_id)
+            merge_request.iid               = pull_request.iid
+            merge_request.title             = pull_request.title
+            merge_request.description       = format_description(pull_request.description, pull_request.author)
+            merge_request.source_project    = pull_request.source_project
+            merge_request.source_branch     = pull_request.source_branch_name
+            merge_request.source_branch_sha = pull_request.source_branch_sha
+            merge_request.target_project    = pull_request.target_project
+            merge_request.target_branch     = pull_request.target_branch_name
+            merge_request.target_branch_sha = pull_request.target_branch_sha
+            merge_request.state             = pull_request.state
+            merge_request.milestone_id      = milestone_id(pull_request.milestone)
+            merge_request.author_id         = author_id
+            merge_request.assignee_id       = user_id(pull_request.assignee)
+            merge_request.created_at        = pull_request.created_at
+            merge_request.updated_at        = pull_request.updated_at
+            merge_request.save!(validate: false)
+
+            merge_request.merge_request_diffs.create
+
+            # Fetch review comments
+            review_comments_url = "/repos/#{repo}/pulls/#{pull_request.iid}/comments"
+            fetch_comments(merge_request, :review_comment, review_comments_url, LegacyDiffNote)
+
+            # Fetch comments
+            comments_url = "/repos/#{repo}/issues/#{pull_request.iid}/comments"
+            fetch_comments(merge_request, :comment, comments_url)
+          rescue => e
+            error(:pull_request, pull_request.url, e.message)
+          ensure
+            clean_up_restored_branches(pull_request)
+          end
+        end
+
+        url = response.rels[:next]
+      end
+    end
+
+    def fetch_issues
+      url = "/repos/#{repo}/issues"
+
+      while url
+        response = Github::Client.new(options).get(url, state: :all, sort: :created, direction: :asc)
+
+        response.body.each do |raw|
+          representation = Github::Representation::Issue.new(raw, options)
+
+          begin
+            # Every pull request is an issue, but not every issue
+            # is a pull request. For this reason, "shared" actions
+            # for both features, like manipulating assignees, labels
+            # and milestones, are provided within the Issues API.
+            if representation.pull_request?
+              next unless representation.has_labels?
+
+              merge_request = MergeRequest.find_by!(target_project_id: project.id, iid: representation.iid)
+              merge_request.update_attribute(:label_ids, label_ids(representation.labels))
+            else
+              next if Issue.where(iid: representation.iid, project_id: project.id).exists?
+
+              author_id          = user_id(representation.author, project.creator_id)
+              issue              = Issue.new
+              issue.iid          = representation.iid
+              issue.project_id   = project.id
+              issue.title        = representation.title
+              issue.description  = format_description(representation.description, representation.author)
+              issue.state        = representation.state
+              issue.label_ids    = label_ids(representation.labels)
+              issue.milestone_id = milestone_id(representation.milestone)
+              issue.author_id    = author_id
+              issue.assignee_id  = user_id(representation.assignee)
+              issue.created_at   = representation.created_at
+              issue.updated_at   = representation.updated_at
+              issue.save!(validate: false)
+
+              # Fetch comments
+              if representation.has_comments?
+                comments_url = "/repos/#{repo}/issues/#{issue.iid}/comments"
+                fetch_comments(issue, :comment, comments_url)
+              end
+            end
+          rescue => e
+            error(:issue, representation.url, e.message)
+          end
+        end
+
+        url = response.rels[:next]
+      end
+    end
+
+    def fetch_comments(noteable, type, url, klass = Note)
+      while url
+        comments = Github::Client.new(options).get(url)
+
+        ActiveRecord::Base.no_touching do
+          comments.body.each do |raw|
+            begin
+              representation  = Github::Representation::Comment.new(raw, options)
+              author_id       = user_id(representation.author, project.creator_id)
+
+              note            = klass.new
+              note.project_id = project.id
+              note.noteable   = noteable
+              note.note       = format_description(representation.note, representation.author)
+              note.commit_id  = representation.commit_id
+              note.line_code  = representation.line_code
+              note.author_id  = author_id
+              note.created_at = representation.created_at
+              note.updated_at = representation.updated_at
+              note.save!(validate: false)
+            rescue => e
+              error(type, representation.url, e.message)
+            end
+          end
+        end
+
+        url = comments.rels[:next]
+      end
+    end
+
+    def fetch_releases
+      url = "/repos/#{repo}/releases"
+
+      while url
+        response = Github::Client.new(options).get(url)
+
+        response.body.each do |raw|
+          representation = Github::Representation::Release.new(raw)
+          next unless representation.valid?
+
+          release = ::Release.find_or_initialize_by(project_id: project.id, tag: representation.tag)
+          next unless relese.new_record?
+
+          begin
+            release.description = representation.description
+            release.created_at  = representation.created_at
+            release.updated_at  = representation.updated_at
+            release.save!(validate: false)
+          rescue => e
+            error(:release, representation.url, e.message)
+          end
+        end
+
+        url = response.rels[:next]
+      end
+    end
+
+    def restore_branches(pull_request)
+      restore_source_branch(pull_request) unless pull_request.source_branch_exists?
+      restore_target_branch(pull_request) unless pull_request.target_branch_exists?
+    end
+
+    def restore_source_branch(pull_request)
+      repository.create_branch(pull_request.source_branch_name, pull_request.source_branch_sha)
+    end
+
+    def restore_target_branch(pull_request)
+      repository.create_branch(pull_request.target_branch_name, pull_request.target_branch_sha)
+    end
+
+    def remove_branch(name)
+      repository.delete_branch(name)
+    rescue Rugged::ReferenceError
+      errors << { type: :branch, url: nil, error: "Could not clean up restored branch: #{name}" }
+    end
+
+    def clean_up_restored_branches(pull_request)
+      return if pull_request.opened?
+
+      remove_branch(pull_request.source_branch_name) unless pull_request.source_branch_exists?
+      remove_branch(pull_request.target_branch_name) unless pull_request.target_branch_exists?
+    end
+
+    def label_ids(labels)
+      labels.map { |attrs| cached[:label_ids][attrs.fetch('name')] }.compact
+    end
+
+    def milestone_id(milestone)
+      return unless milestone.present?
+
+      project.milestones.select(:id).find_by(iid: milestone.iid)&.id
+    end
+
+    def user_id(user, fallback_id = nil)
+      return unless user.present?
+      return cached[:user_ids][user.id] if cached[:user_ids].key?(user.id)
+
+      gitlab_user_id = user_id_by_external_uid(user.id) || user_id_by_email(user.email)
+
+      cached[:gitlab_user_ids][user.id] = gitlab_user_id.present?
+      cached[:user_ids][user.id] = gitlab_user_id || fallback_id
+    end
+
+    def user_id_by_email(email)
+      return nil unless email
+
+      ::User.find_by_any_email(email)&.id
+    end
+
+    def user_id_by_external_uid(id)
+      return nil unless id
+
+      ::User.select(:id)
+            .joins(:identities)
+            .merge(::Identity.where(provider: :github, extern_uid: id))
+            .first&.id
+    end
+
+    def format_description(body, author)
+      return body if cached[:gitlab_user_ids][author.id]
+
+      "*Created by: #{author.username}*\n\n#{body}"
+    end
+
+    def expire_repository_cache
+      repository.expire_content_cache
+    end
+
+    def keep_track_of_errors
+      return unless errors.any?
+
+      project.update_column(:import_error, {
+        message: 'The remote data could not be fully imported.',
+        errors: errors
+      }.to_json)
+    end
+
+    def error(type, url, message)
+      errors << { type: type, url: Gitlab::UrlSanitizer.sanitize(url), error: message }
+    end
+  end
+end

lib/github/rate_limit.rb

+module Github
+  class RateLimit
+    SAFE_REMAINING_REQUESTS = 100
+    SAFE_RESET_TIME         = 500
+    RATE_LIMIT_URL          = '/rate_limit'.freeze
+
+    attr_reader :connection
+
+    def initialize(connection)
+      @connection = connection
+    end
+
+    def get
+      response = connection.get(RATE_LIMIT_URL)
+
+      # GitHub Rate Limit API returns 404 when the rate limit is disabled
+      return false unless response.status != 404
+
+      body      = Oj.load(response.body, class_cache: false, mode: :compat)
+      remaining = body.dig('rate', 'remaining').to_i
+      reset_in  = body.dig('rate', 'reset').to_i
+      exceed    = remaining <= SAFE_REMAINING_REQUESTS
+
+      [exceed, reset_in]
+    end
+  end
+end

lib/github/repositories.rb

+module Github
+  class Repositories
+    attr_reader :options
+
+    def initialize(options)
+      @options = options
+    end
+
+    def fetch
+      Collection.new(options).fetch(repos_url)
+    end
+
+    private
+
+    def repos_url
+      '/user/repos'
+    end
+  end
+end

lib/github/representation/base.rb

+module Github
+  module Representation
+    class Base
+      def initialize(raw, options = {})
+        @raw     = raw
+        @options = options
+      end
+
+      def id
+        raw['id']
+      end
+
+      def url
+        raw['url']
+      end
+
+      def created_at
+        raw['created_at']
+      end
+
+      def updated_at
+        raw['updated_at']
+      end
+
+      private
+
+      attr_reader :raw, :options
+    end
+  end
+end

lib/github/representation/branch.rb

+module Github
+  module Representation
+    class Branch < Representation::Base
+      attr_reader :repository
+
+      def user
+        raw.dig('user', 'login') || 'unknown'
+      end
+
+      def repo
+        return @repo if defined?(@repo)
+
+        @repo = Github::Representation::Repo.new(raw['repo']) if raw['repo'].present?
+      end
+
+      def ref
+        raw['ref']
+      end
+
+      def sha
+        raw['sha']
+      end
+
+      def short_sha
+        Commit.truncate_sha(sha)
+      end
+
+      def exists?
+        branch_exists? && commit_exists?
+      end
+
+      def valid?
+        sha.present? && ref.present?
+      end
+
+      private
+
+      def branch_exists?
+        repository.branch_exists?(ref)
+      end
+
+      def commit_exists?
+        repository.branch_names_contains(sha).include?(ref)
+      end
+
+      def repository
+        @repository ||= options.fetch(:repository)
+      end
+    end
+  end
+end

lib/github/representation/comment.rb

+module Github
+  module Representation
+    class Comment < Representation::Base
+      def note
+        raw['body'] || ''
+      end
+
+      def author
+        @author ||= Github::Representation::User.new(raw['user'], options)
+      end
+
+      def commit_id
+        raw['commit_id']
+      end
+
+      def line_code
+        return unless on_diff?
+
+        parsed_lines = Gitlab::Diff::Parser.new.parse(diff_hunk.lines)
+        generate_line_code(parsed_lines.to_a.last)
+      end
+
+      private
+
+      def generate_line_code(line)
+        Gitlab::Diff::LineCode.generate(file_path, line.new_pos, line.old_pos)
+      end
+
+      def on_diff?
+        diff_hunk.present?
+      end
+
+      def diff_hunk
+        raw['diff_hunk']
+      end
+
+      def file_path
+        raw['path']
+      end
+    end
+  end
+end

lib/github/representation/issuable.rb

+module Github
+  module Representation
+    class Issuable < Representation::Base
+      def iid
+        raw['number']
+      end
+
+      def title
+        raw['title']
+      end
+
+      def description
+        raw['body'] || ''
+      end
+
+      def milestone
+        return unless raw['milestone'].present?
+
+        @milestone ||= Github::Representation::Milestone.new(raw['milestone'])
+      end
+
+      def author
+        @author ||= Github::Representation::User.new(raw['user'], options)
+      end
+
+      def assignee
+        return unless assigned?
+
+        @assignee ||= Github::Representation::User.new(raw['assignee'], options)
+      end
+
+      def assigned?
+        raw['assignee'].present?
+      end
+    end
+  end
+end

lib/github/representation/issue.rb

+module Github
+  module Representation
+    class Issue < Representation::Issuable
+      def labels
+        raw['labels']
+      end
+
+      def state
+        raw['state'] == 'closed' ? 'closed' : 'opened'
+      end
+
+      def has_comments?
+        raw['comments'] > 0
+      end
+
+      def has_labels?
+        labels.count > 0
+      end
+
+      def pull_request?
+        raw['pull_request'].present?
+      end
+    end
+  end
+end

lib/github/representation/label.rb

+module Github
+  module Representation
+    class Label < Representation::Base
+      def color
+        "##{raw['color']}"
+      end
+
+      def title
+        raw['name']
+      end
+    end
+  end
+end

lib/github/representation/milestone.rb

+module Github
+  module Representation
+    class Milestone < Representation::Base
+      def iid
+        raw['number']
+      end
+
+      def title
+        raw['title']
+      end
+
+      def description
+        raw['description']
+      end
+
+      def due_date
+        raw['due_on']
+      end
+
+      def state
+        raw['state'] == 'closed' ? 'closed' : 'active'
+      end
+    end
+  end
+end

lib/github/representation/pull_request.rb

+module Github
+  module Representation
+    class PullRequest < Representation::Issuable
+      attr_reader :project
+
+      delegate :user, :repo, :ref, :sha, to: :source_branch, prefix: true
+      delegate :user, :exists?, :repo, :ref, :sha, :short_sha, to: :target_branch, prefix: true
+
+      def source_project
+        project
+      end
+
+      def source_branch_exists?
+        !cross_project? && source_branch.exists?
+      end
+
+      def source_branch_name
+        @source_branch_name ||=
+          if cross_project? || !source_branch_exists?
+            source_branch_name_prefixed
+          else
+            source_branch_ref
+          end
+      end
+
+      def target_project
+        project
+      end
+
+      def target_branch_name
+        @target_branch_name ||= target_branch_exists? ? target_branch_ref : target_branch_name_prefixed
+      end
+
+      def state
+        return 'merged' if raw['state'] == 'closed' && raw['merged_at'].present?
+        return 'closed' if raw['state'] == 'closed'
+
+        'opened'
+      end
+
+      def opened?
+        state == 'opened'
+      end
+
+      def valid?
+        source_branch.valid? && target_branch.valid?
+      end
+
+      private
+
+      def project
+        @project ||= options.fetch(:project)
+      end
+
+      def source_branch
+        @source_branch ||= Representation::Branch.new(raw['head'], repository: project.repository)
+      end
+
+      def source_branch_name_prefixed
+        "gh-#{target_branch_short_sha}/#{iid}/#{source_branch_user}/#{source_branch_ref}"
+      end
+
+      def target_branch
+        @target_branch ||= Representation::Branch.new(raw['base'], repository: project.repository)
+      end
+
+      def target_branch_name_prefixed
+        "gl-#{target_branch_short_sha}/#{iid}/#{target_branch_user}/#{target_branch_ref}"
+      end
+
+      def cross_project?
+        return true if source_branch_repo.nil?
+
+        source_branch_repo.id != target_branch_repo.id
+      end
+    end
+  end
+end

lib/github/representation/release.rb

+module Github
+  module Representation
+    class Release < Representation::Base
+      def description
+        raw['body']
+      end
+
+      def tag
+        raw['tag_name']
+      end
+
+      def valid?
+        !raw['draft']
+      end
+    end
+  end
+end

lib/github/representation/repo.rb

+module Github
+  module Representation
+    class Repo < Representation::Base
+    end
+  end
+end

lib/github/representation/user.rb

+module Github
+  module Representation
+    class User < Representation::Base
+      def email
+        return @email if defined?(@email)
+
+        @email = Github::User.new(username, options).get.fetch('email', nil)
+      end
+
+      def username
+        raw['login']
+      end
+    end
+  end
+end

lib/github/response.rb

+module Github
+  class Response
+    attr_reader :raw, :headers, :status
+
+    def initialize(response)
+      @raw     = response
+      @headers = response.headers
+      @status  = response.status
+    end
+
+    def body
+      Oj.load(raw.body, class_cache: false, mode: :compat)
+    end
+
+    def rels
+      links = headers['Link'].to_s.split(', ').map do |link|
+        href, name = link.match(/<(.*?)>; rel="(\w+)"/).captures
+
+        [name.to_sym, href]
+      end
+
+      Hash[*links.flatten]
+    end
+  end
+end