Ruby on rails 4 /contacts未初始化常量Contact:：GoogleDrive处的名称错误

我现在正在学习“RailsApps项目”Rails 4.1教程，并且一直停留在电子表格连接部分。在测试应用程序时，我遇到以下错误：

NameError at /contacts
uninitialized constant Contact::GoogleDrive

update_spreadsheet () Users/sikendersingh/sideshow/learn-rails/app/models/contact.rb

  validates_presence_of :content
  validates_format_of :email, :with => /\A[-a-z0-9_+\.]+\@([-a-z0-9]+\.)+[a-z0-9]{2,4}\z/i
  validates_length_of :content, :maximum => 500
  def update_spreadsheet
    connection = GoogleDrive.login(Rails.application.secrets.email_provider_username, Rails.application.secrets.email_provider_password
)
    ss = connection.spreadsheet_by_title('Learn-Rails-Example')
    if ss.nil?
      ss = connection.create_spreadsheet('Learn-Rails-Example')
    end

以下是整个文件：

class Contact < ActiveRecord::Base
  has_no_table

  column :name, :string
  column :email, :string
  column :content, :string

  validates_presence_of :name
  validates_presence_of :email
  validates_presence_of :content
  validates_format_of :email, :with => /\A[-a-z0-9_+\.]+\@([-a-z0-9]+\.)+[a-z0-9]{2,4}\z/i
  validates_length_of :content, :maximum => 500

  def update_spreadsheet
    connection = GoogleDrive.login(Rails.application.secrets.email_provider_username, Rails.application.secrets.email_provider_password
)
    ss = connection.spreadsheet_by_title('Learn-Rails-Example')
    if ss.nil?
      ss = connection.create_spreadsheet('Learn-Rails-Example')
    end
    ws = ss.worksheets[0]
    last_row = 1 + ws.num_rows
    ws[last_row, 1] = Time.new
    ws[last_row, 2] = self.name
    ws[last_row, 3] = self.email
    ws[last_row, 4] = self.content
    ws.save
  end

end

class联系人/\A[-A-z0-9\+\.]+\@（[-A-z0-9]+\.）+[A-z0-9]{2,4}\z/i
验证的长度为：content，：max=>500
def更新电子表格
connection=GoogleDrive.login（Rails.application.secrets.email\u provider\u用户名，Rails.application.secrets.email\u provider\u密码
)
ss=连接。电子表格按标题（“Learn-Rails-Example”）
如果ss.nil？
ss=连接。创建_电子表格（'Learn-Rails-Example'）
终止
ws=ss.工作表[0]
最后一行=1+ws.num行
ws[最后一行，1]=Time.new
ws[last_row，2]=self.name
ws[最后一行，3]=self.email
ws[最后一行，4]=self.content
ws.save
终止
终止

发现问题：

意外地安装了“google drive”gem而不是“google_drive”gem

在secrets.yml文件中，我有实际的用户名、密码等，而不是“GMAIL_username”，然后再去查看我的bashrc文件

---

你安装了gem'google_drive'吗？是的，全部安装了，这是我的gem文件：ource'ruby'2.1.1'gem'rails'，4.1.1'#rails defaults gem'sqlite3'gem'sass rails'，'~>4.0.3'gem'uglifier'，'>=1.3.0'gem'coffee rails'，'~>4.0.0'gem'jquery rails'gem'turbolinks'gem'jbuilder，'>2.0'gem'spring'，小组：：开发#学习rails gem'activerecord无表'gem'基础rails'gem'长臂猿'gem'谷歌硬盘'gem'高压'gem'简单形式'gem'小组：开发做gem'更好的错误'gem'安静的资产'gem'rails\u布局'end