Rails 5：查找属于公司的所有用户，这些用户属于 current_user

Question

In my app User can have many Companies and vice versa. In Accounts table id of User and id of its Company is stored. I want to find all Users who belong to Companies, which belong to current_user. Let's assume that the current_user is like master User (not Admin, as that would be system Admin) of those companies. How do I do this? My guess is to do it with Arel, but then how should it look in Model, Controller, View? Many thanks for any help. I'm on Rails 5.

models/user.rb

class User < ApplicationRecord
has_many :accounts, dependent: :destroy
has_many :companies, through: :accounts

models/account.rb

class Account < ApplicationRecord
belongs_to :company
belongs_to :user
accepts_nested_attributes_for :company, :user

models/company.rb

class Company < ApplicationRecord
has_many :accounts, dependent: :destroy
has_many :users, through: :accounts
accepts_nested_attributes_for :accounts, :users

My schema.rb looks like this:

create_table "accounts", force: :cascade do |t|
t.integer  "company_id"
t.integer  "user_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.index ["company_id"], name: "index_accounts_on_company_id"
t.index ["user_id"], name: "index_accounts_on_user_id"
end

  create_table "companies", force: :cascade do |t|
t.string   "name"
t.string   "legal_name"
t.string   "reg_number"
t.string   "address"
t.string   "bank_acc"
t.string   "description"
t.string   "website"
t.datetime "created_at",              null: false
t.datetime "updated_at",              null: false
t.integer  "role",        default: 0
t.integer  "currency",    default: 0
end

  create_table "users", force: :cascade do |t|
t.string   "name"
t.string   "email"
t.datetime "created_at",                      null: false
t.datetime "updated_at",                      null: false
t.string   "password_digest"
t.string   "remember_digest"
t.boolean  "admin",           default: false
t.index ["email"], name: "index_users_on_email", unique: true
end

Answer 1

You can find current user's companies, and eager load users who belong to those companies

@companies = current_user.companies.includes(:users)

To list all users(may be in a view), loop through @companies and all its users

@companies.each do |company|
  company.users.each do |user|
    puts user.name
  end
end

Or use map/collect to assign them to a variable.

@users = @companies.map(&:users).flatten