Ruby on rails 获取创建消息ruby on rails mongoid的用户

我正在尝试一个查询，以获取在特定sala中创建消息的用户，但我找不到方法。 我有查询来获取特定sala的消息，但无法获取创建消息的用户

Mensajes_控制器（我从sala获得信息的地方）

设置_sala（获取我想要的信息的房间）

门萨耶模型

class Mensaje
  include Mongoid::Document
  include Mongoid::Timestamps::Created

      field :cuerpo, type: String

      validates :cuerpo, presence: true

      belongs_to :user, foreign_key: :user_id
      belongs_to :sala, foreign_key: :sala_id

end

用户模型

class User
    include Mongoid::Document
    include ActiveModel::SecurePassword

      has_secure_password
      field :password_digest, type: String
      field :email, type: String
      field :nombre, type: String

      has_many :salas
      has_many :mensajes

      validates :nombre, presence: true
      validates :email, presence: true
      validates :password_digest, presence: true

end

更新-Gemfile

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.5.5'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '~> 5.2.3'
# Use Puma as the app server
gem 'puma', '~> 3.11'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.5'
# Use Redis adapter to run Action Cable in production
gem 'redis', '~> 4.0'
# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.12'
gem 'bcrypt', '~> 3.1.7'
gem 'mongoid-bcrypt-ruby'

gem 'devise'

gem 'kaminari-mongoid'
gem 'mongo'
# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

gem 'mongoid', '~> 7.0.5'

# Reduces boot times through caching; required in config/boot.rb
gem 'bootsnap', '>= 1.1.0', require: false

# Use Rack CORS for handling Cross-Origin Resource Sharing (CORS), making cross-origin AJAX possible
gem 'rack-cors'

gem 'jwt_sessions', '~> 2.3'
gem 'mongoid-rspec', github: 'mongoid/mongoid-rspec', ref: '68c95b133be1a1482fe882e39afd33262147d1f4'

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
  gem 'pry-rails'
  gem 'rspec-rails'
  gem 'factory_bot_rails'
  gem 'shoulda-matchers'
end

group :development do
  gem 'listen', '>= 3.0.5', '< 3.2'
  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
end


# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

源代码'https://rubygems.org'
git|u源（：github）{| repo |“https://github.com/#{repo}.git}
ruby“2.5.5”
#捆绑边缘Rails：gem'Rails'，github'Rails/Rails'
gem'rails'，“~>5.2.3”
#使用Puma作为应用程序服务器
宝石“彪马”，“大于3.11”
#轻松构建JSON API。阅读更多：https://github.com/rails/jbuilder
gem'jbuilder'，“~>2.5”
#使用Redis适配器在生产中运行操作电缆
gem'redis'，“~>4.0”
#使用ActiveModel具有\u安全\u密码
#gem'bcrypt'，“~>3.1.12”
gem'bcrypt'，“~>3.1.7”
宝石“mongoid bcrypt ruby”
宝石“设计”
宝石“kaminari mongoid”
宝石“mongo”
#使用Capistrano进行部署
#gem“capistrano rails”，集团：：开发
gem'mongoid'，“~>7.0.5”
#通过缓存减少启动时间；config/boot.rb中需要
gem'bootsnap'，'>=1.1.0'，require:false
#使用机架CORS处理跨源资源共享（CORS），使跨源AJAX成为可能
宝石“机架cors”
gem“jwt_课程”，“~>2.3”
gem“mongoid rspec”，github：“mongoid/mongoid rspec”，参考：“68c95b133be1a1482fe882e39afd33262147d1f4”
小组：开发，：测试
#在代码中的任意位置调用“byebug”以停止执行并获得调试器控制台
gem'byebug'，平台：[：mri，：mingw，：x64_mingw]
宝石“撬轨”
gem'rspec rails'
gem“工厂机器人轨道”
宝石“应该是匹配者”
结束
小组：发展怎么办
gem'listen'，'>=3.0.5'，'<3.2'
#Spring通过让应用程序在后台运行来加速开发。阅读更多：https://github.com/rails/spring
宝石“春天”
gem‘SpringWatcherListen’，“~>2.0.0”
结束
#Windows不包括zoneinfo文件，因此捆绑tzinfo数据
gem'tzinfo data'，平台：[:mingw，:mswin，:x64_mingw，:jruby]

您可以随时提出任何您可能需要的问题。谢谢

这个怎么样

@mensaje.user

---

安装kaminari mongoid，也许还有mongo gem。

这是我尝试时抛出的错误：NoMethodError（未定义的方法“user”for#）在创建

@mensaje

作为

@mensaje=@sala.mensajes.desc（“'u id'）.limit（20）之前，尝试
@mensaje
@mensaje

？尝试

Mensaje.last.user

NoMethodError（未定义的方法用户用于nil:NilClass）

？是否确定此模型至少有一个对象？检查pls

Mensaje.all

class User
    include Mongoid::Document
    include ActiveModel::SecurePassword

      has_secure_password
      field :password_digest, type: String
      field :email, type: String
      field :nombre, type: String

      has_many :salas
      has_many :mensajes

      validates :nombre, presence: true
      validates :email, presence: true
      validates :password_digest, presence: true

end

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.5.5'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '~> 5.2.3'
# Use Puma as the app server
gem 'puma', '~> 3.11'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.5'
# Use Redis adapter to run Action Cable in production
gem 'redis', '~> 4.0'
# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.12'
gem 'bcrypt', '~> 3.1.7'
gem 'mongoid-bcrypt-ruby'

gem 'devise'

gem 'kaminari-mongoid'
gem 'mongo'
# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

gem 'mongoid', '~> 7.0.5'

# Reduces boot times through caching; required in config/boot.rb
gem 'bootsnap', '>= 1.1.0', require: false

# Use Rack CORS for handling Cross-Origin Resource Sharing (CORS), making cross-origin AJAX possible
gem 'rack-cors'

gem 'jwt_sessions', '~> 2.3'
gem 'mongoid-rspec', github: 'mongoid/mongoid-rspec', ref: '68c95b133be1a1482fe882e39afd33262147d1f4'

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
  gem 'pry-rails'
  gem 'rspec-rails'
  gem 'factory_bot_rails'
  gem 'shoulda-matchers'
end

group :development do
  gem 'listen', '>= 3.0.5', '< 3.2'
  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
end


# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]