Question

我正在使用Rails 4中的一个简单的项目管理工具，让我头疼的部分有三个主要模型：Projects，Users和Memberships。

用户可以有很多项目，项目可以有很多用户。我以下列方式在Projects和Users之间实现了has_many through成员关系：

项目：

class Project < ActiveRecord::Base
  has_many :memberships
  has_many :users, through: :memberships
end

用户：

class User < ActiveRecord::Base
   has_many :memberships
   has_many :projects, through: :memberships
end

成员：

class Membership < ActiveRecord::Base
    belongs_to :user
    belongs_to :project
end

到目前为止，我还没有在Stack Overflow上看到它，但我为成员资格创建了一个单独的控制器，只有:create和:destroy。到目前为止，:create似乎工作正常。

主要问题在于会员资格的销毁功能。我实现的销毁功能是：

def destroy
    Membership.find(:id).destroy
    redirect_to current_project || request.referer
end

rake routes表示会员资格路径存在，但以下尝试给我：

我尝试使用link_to helper删除会员资格：

<%= link_to "delete", membership, method: :delete %> 
EDIT: error: undefined local variable or method `membership' 

<%= link_to "delete", @membership, method: :delete %>
EDIT: error: Sorry something went wrong --> goes to /memberships

<%= link_to "delete, membership_path(@membership), method: :delete %>
EDIT: error No route matches {:action=>"destroy", :controller=>"memberships", :id=>nil} missing required keys: [:id]

都会出错。

编辑：根据要求还提供projects_controller #show功能

def show
    @user = current_user
    @project = current_user.projects.find(params[:id])
    @members = @project.users
    @projects = @user.projects
    @membership = @project.memberships.build if logged_in?
    @memberships = @project.memberships
end

如何确保使用@project.membership_ids中的关联ID删除成员身份？我应该包含一些额外的参数吗？

Answer 1

resources :memberships, only: [:create, :destroy]

更新

在你的摧毁行动Membership.find(:id).destroy中，不知道我早些时候错过了这个。它应该利用params并且更符合这一点：

# MembershipsController
def destroy
    @membership = Membership.find(params[:id])
    if @membership.destroy
        redirect_to current_project || request.referer
    else
        #
    end
end

您的ProjectsController显示操作并未将@membership定义为Membership个对象。

def show
    @user = current_user
    @project = @user.projects.find(params[:id])
    @membership = Membership.find_by user: @user, project: @project

    # build is used for nested attributes, not sure why you'd have this in a show action...
    # @project.memberships.build if logged_in?

    # the following are redundant.
    @projects = @user.projects
    @members = @project.users
    @memberships = @project.memberships
end

在视图中：<%= link_to "delete", @membership, method: :delete %>

如果您希望在删除父项后销毁项目或用户的所有成员资格，请对User＆amp; Project型号：

class Project < ActiveRecord::Base
    has_many :memberships, dependent: :destroy
    has_many :users, through: :memberships
end

class User < ActiveRecord::Base
    has_many :memberships, dependent: :destroy
    has_many :projects, through: :memberships
end

Answer 2

您的代码无效的原因是您没有指定link_to的路径。我不相信你需要@membership所以我编辑了它。

<%= link_to "delete", membership_path(@membership), method: :delete %>

销毁has_many：通过不使用link_to帮助程序

2 个答案:

更新