【发布时间】：2018-04-06 21:25:58
【问题描述】：
这是一个很常见的问题，有几十篇博客文章涵盖了这个问题。我只是不知道我做错了什么。 抱歉，帖子太长了。
我有一个Mono-Transitive many-to-many relationship。
一个会话可能有多个字幕。字幕员可能有多个会话。多对多关系由“成员”完成。
class Session < ApplicationRecord
# This will tell to delete all the memberships
# in case the current session is deleted.
has_many :memberships, dependent: :destroy
# Added this, see:
# https://www.sitepoint.com/master-many-to-many-associations-with-activerecord/
has_many :captionists, through: :memberships
# https://www.sitepoint.com/complex-rails-forms-with-nested-attributes/
# Allows us to delete the membersihps if not included.
accepts_nested_attributes_for :memberships, :allow_destroy => true
validates :uuid, presence: true, uniqueness: true
validates :name, presence: true, uniqueness: false
validates :url, presence: true, uniqueness: true
validates :passcode, presence: true, uniqueness: true
validates :shortcode, presence: true, uniqueness: true
end
class Captionist < ApplicationRecord
has_many :memberships
# Added this, see:
# https://www.sitepoint.com/master-many-to-many-associations-with-activerecord/
has_many :sessions, through: :memberships
validates :uuid, presence: true, uniqueness: true
validates :full_name, presence: true, uniqueness: false
validates :access_token, presence: true, uniqueness: true
validates :passcode, presence: true, uniqueness: false
end
# Mono Transitive Association
# https://www.sitepoint.com/master-many-to-many-associations-with-activerecord/
class Membership < ApplicationRecord
belongs_to :session
belongs_to :captionist
validates :uuid, presence: true, uniqueness: true
validates :hostname, presence: true, uniqueness: false
validates :web_port, presence: true, uniqueness: false
validates :tcp_port, presence: true, uniqueness: false
end
这是我的 session_controller（它在管理命名空间下）
module Admin
class SessionsController < Admin::BaseAdminController
def index
# List of sessions
# Careful on not to iterate through everything, as Rails will interpret it
# as all.
# Default is #25
# This uses the kaminari gem.
# https://github.com/kaminari/kaminari
@sessions = Session.page(params[:page] || 1)
@page_count = @sessions.total_pages
end
def edit
@session = Session.includes(:memberships).includes(:captionists).find(params[:id])
if !@session
raise ActionController::RoutingError.new('Not Found')
end
end
def update
@session = Session.find(params[:id])
if @session.update_attributes(session_params)
respond_to do |format|
format.html { redirect_to edit_admin_session_path , notice: 'Session was successfully updated.' }
end
return
end
render 'edit'
end
def session_params
return params.require(:session).permit(:name, :passcode, :shortcode,
membership_attributes: [:id, :hostname, :tag_teaming, :web_port, :tcp_port, :allowing_connections, :_destroy])
end
end
end
最后但并非最不重要的一点是 .erb 文件：
<h1>Editting!!</h1>
<%= link_to 'Go Back To list', admin_sessions_path %>
<%= form_for :session, method: :patch, class:'container' do |f| %>
<div class="form-group">
<%= f.label :name %>
<%= f.text_field :name, class: 'form-control' %><br />
</div>
<div class="form-group">
<%= f.label :passcode %>
<%= f.text_field :passcode, class: 'form-control' %><br />
</div>
<%= f.label :shortcode %>
<%= f.text_field :shortcode, class: 'form-control' %><br />
<%= f.label :memberships %>
<table class="table table-striped table-hover">
<thead class="thead-dark">
<tr>
<th scope="col"> Allowing Connections </th>
<th scope="col">Tag Teaming</th>
<th scope="col">Hostname</th>
<th scope="col">Web Port</th>
<th scope="col">TCP Port</th>
<th scope="col">Captionist Name </th>
<th scope="col">Action</th>
</tr>
</thead>
<!-- HERE'S THE PART THAT is giving me the problem -->
<% @session.memberships.map do |membership| %>
<%= f.fields_for membership do |ff| %>
<tr class="nested-fields">
<%= ff.hidden_field :id %>
<td>
<%= ff.label :allowing_connections %>
<%= ff.check_box :allowing_connections %>
</td>
<td>
<%= ff.label :tag_teaming %>
<%= ff.check_box :tag_teaming %>
</td>
<td>
<%= ff.label :hostname %>
<%= ff.text_field :hostname %>
</td>
<td>
<%= ff.label :web_port %>
<%= ff.text_field :web_port %>
</td>
<td>
<%= ff.label :tcp_port %>
<%= ff.text_field :tcp_port %>
</td>
<td>
<%= membership.captionist.full_name %>
</td>
<td>
<%= ff.check_box :_destroy %>
</td>
</tr>
<% end %>
<% end %>
</table>
<%= f.submit 'Update', class: 'btn btn-primary' %>
<% end %>
这里是发送的参数：
{"name"=>"Session Correct name", "passcode"=>"A Passcode", "shortcode"=>"A Shortcode", "membership"=>{"id"=>"106", "allowing_connections"=>"0", "tag_teaming"=>"0", "hostname"=>"delete hostname", "web_port"=>"80", "tcp_port"=>"3001", "_destroy"=>"0"}} permitted: false>
这是我将参数列入白名单的方式：
return params.require(:session).permit(:name, :passcode, :shortcode,
membership_attributes: [:id, :hostname, :tag_teaming, :web_port, :tcp_port, :allowing_connections, :_destroy])
有什么问题？
1) 现在，如果我提交我得到的表单： unpermitted_params=["membership"] 在控制台的末尾 2) 我检查了数据库是否已正确迁移。外键设置正确。我可以毫无问题地浏览属性。我所做的是在执行迁移后添加关系 has_many 。我不知道是否需要添加某种迁移才能使更新正常工作。 3）我试过替换
<%= form_for :session, method: :patch, class:'container' do |f| %>
对于：
但我收到一个错误：
找不到#的有效映射
4) 我也尝试删除 <% @session.memberships.map do |membership| %>，但我不会填充这些字段。我看到的另一个问题是输入的名称都是相同的。每当我发送要更新的参数时，它只是被反映的嵌套部分的最后一个。
这是来自服务器的响应（params[:session]）：
Parameters {"name"=>"Session Correct name", "passcode"=>"A Passcode", "shortcode"=>"A Shortcode", "membership"=>{"id"=>"106", "allowing_connections"=>"0", "tag_teaming"=>"0", "hostname"=>"delete hostname", "web_port"=>"80", "tcp_port"=>"3001", "_destroy"=>"0"}} permitted: false>
不嵌套的部分得到更新。
有什么想法吗？
谢谢！
编辑（2018 年 4 月 9 日）：添加了发送的参数（我这里没有）。修复了格式和 HTML 的问题。
【问题讨论】：
-
看起来参数在这里的格式中丢失了：> 这是发送的参数：
-
不确定这是否与任何事情有关，但我不建议将隐藏字段放在
和 之间。这可能会导致语法错误，并可能在渲染中丢失。 @emptywalls：感谢您指出这一点！另外，感谢隐藏字段。我要把它从那里移到桌子外面。@JoseA：实际上，我把它移到了
标签： ruby-on-rails activerecord erb nested-forms form-for