Search results libraries added

Gitlab::SearchResults and Gitlab::ProjectSearchResults are libraries we
are going to use to get search results based on query, enitity type and
pagination.

It will allow us to get only issues from project #23 where title or
description includes 'foo'.

Ex:

search_results = Gitlab::ProjectSearchResults.new(project.id, 'foo', 'issues')

search_results.objects => # [<Issues #23>, <Issues #34>]
search_results.issues_count => 2
search_results.total_count => 12 (it includes results from comments and
merge requests too)
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

lib/gitlab/project_search_results.rb

+module Gitlab
+  class ProjectSearchResults < SearchResults
+    attr_reader :project, :repository_ref
+
+    def initialize(project_id, query, scope = nil, page = nil, repository_ref = nil)
+      @project = Project.find(project_id)
+      @repository_ref = repository_ref
+      @page = page
+      @query = Shellwords.shellescape(query) if query.present?
+      @scope = scope
+
+      unless %w(blobs notes issues merge_requests).include?(@scope)
+        @scope = default_scope
+      end
+    end
+
+    def objects
+      case scope
+      when 'notes'
+        notes.page(page).per(per_page)
+      when 'blobs'
+        Kaminari.paginate_array(blobs).page(page).per(per_page)
+      else
+        super
+      end
+    end
+
+    def total_count
+      @total_count ||= issues_count + merge_requests_count + blobs_count + notes_count
+    end
+
+    def blobs_count
+      @blobs_count ||= blobs.count
+    end
+
+    def notes_count
+      @notes_count ||= notes.count
+    end
+
+    private
+
+    def blobs
+      if project.empty_repo?
+        []
+      else
+        project.repository.search_files(query, repository_ref)
+      end
+    end
+
+    def notes
+      Note.where(project_id: limit_project_ids).search(query).order('updated_at DESC')
+    end
+
+    def default_scope
+      'blobs'
+    end
+
+    def limit_project_ids
+      [project.id]
+    end
+  end
+end

lib/gitlab/search_results.rb

+module Gitlab
+  class SearchResults
+    attr_reader :scope, :objects, :query, :page
+
+    # Limit search results by passed project ids
+    # It allows us to search only for projects user has access to
+    attr_reader :limit_project_ids
+
+    def initialize(limit_project_ids, query, scope = nil, page = nil)
+      @limit_project_ids = limit_project_ids || Project.all
+      @page = page
+      @query = Shellwords.shellescape(query) if query.present?
+      @scope = scope
+
+      unless %w(projects issues merge_requests).include?(@scope)
+        @scope = default_scope
+      end
+    end
+
+    def objects
+      case scope
+      when 'projects'
+        projects.page(page).per(per_page)
+      when 'issues'
+        issues.page(page).per(per_page)
+      when 'merge_requests'
+        merge_requests.page(page).per(per_page)
+      else
+        Kaminari.paginate_array([]).page(page).per(per_page)
+      end
+    end
+
+    def total_count
+      @total_count ||= projects_count + issues_count + merge_requests_count
+    end
+
+    def projects_count
+      @projects_count ||= projects.count
+    end
+
+    def issues_count
+      @issues_count ||= issues.count
+    end
+
+    def merge_requests_count
+      @merge_requests_count ||= merge_requests.count
+    end
+
+    def empty?
+      total_count.zero?
+    end
+
+    private
+
+    def projects
+      Project.where(id: limit_project_ids).search(query)
+    end
+
+    def issues
+      Issue.where(project_id: limit_project_ids).search(query).order('updated_at DESC')
+    end
+
+    def merge_requests
+      MergeRequest.in_projects(limit_project_ids).search(query).order('updated_at DESC')
+    end
+
+    def default_scope
+      'projects'
+    end
+
+    def per_page
+      20
+    end
+  end
+end