sample08.rb

get '/sample08' do
  haml :sample08
end

post '/sample08' do

  set :client_id, params[:clientId]
  set :private_key, params[:privateKey]
  set :guid, params[:guid]
  set :page_number, params[:pageNumber]
  set :source, params[:source]
  set :file_id, params[:fileId]
  set :base_path, params[:basePath]

  begin

    raise 'Please enter all required parameters' if settings.client_id.empty? or settings.private_key.empty?

    if settings.base_path.empty?
      base_path = 'https://api.groupdocs.com'
    elsif settings.base_path.match('/v2.0')
      base_path = settings.base_path.split('/v2.0')[0]
    else
      base_path = settings.base_path
    end

    GroupDocs.configure do |groupdocs|
      groupdocs.client_id = settings.client_id
      groupdocs.private_key = settings.private_key

      groupdocs.api_server = base_path # default is 'https://api.groupdocs.com'
    end

    file = nil
    doc = nil
    metadata = nil

    case settings.source
      when 'guid'
        file = GroupDocs::Storage::File.new({:guid => settings.file_id})
      when 'local'

        filepath = "#{Dir.tmpdir}/#{params[:file][:filename]}"

        File.open(filepath, 'wb') { |f| f.write(params[:file][:tempfile].read) }

        file = GroupDocs::Storage::File.upload!(filepath, {})
      when 'url'
        file = GroupDocs::Storage::File.upload_web!(settings.url)
      else
        raise 'Wrong GUID source.'
    end

    doc = file.to_document
    metadata = doc.metadata!()

    images = doc.page_images!(800, 400, {:first_page => 0, :page_count => metadata.views_count})

    unless images.empty?
      image = images[Integer(settings.page_number)]
    end

  rescue Exception => e
    err = e.message
  end

  haml :sample08, :locals => {:clientId => settings.client_id, :privateKey => settings.private_key, :guid => settings.guid, :pageNumber => settings.page_number, :image => image, :err => err}
end