没有路线匹配...缺少必需的键答案

【问题标题】：No route matches ... missing required keys没有路线匹配...缺少必需的键
【发布时间】：2017-10-17 01:05:56
【问题描述】：

我有两个控制器和型号Projects 和Schemas。 Schemasbelongs_to 项目。 Projectshas_manyschemas。我正在寻找http://localhost:3000/projects/SLUG-PROJECT/schemas/SLUG-SCHEMA。

以下是我的SchemaController 代码：

class Projects::SchemasController < ApplicationController
  before_action :set_schema, only: [:show, :edit, :update, :destroy]
  before_action :set_project, only: [:index, :show, :new, :edit, :update, :destroy]


  def index
    @schemas = Schema.all
  end


  def show
  end


  def new
    @schema = Schema.new
  end


  def edit
  end


  def create
    @schema = Schema.new(schema_params)

    respond_to do |format|
      if @schema.save
        format.html { redirect_to project_url(@schema.project_id), notice: 'Schema was successfully created.' }
      else
        format.html { render :new }
      end
    end
  end


  def update
    respond_to do |format|
      if @schema.update(schema_params)
        format.html { redirect_to project_url(@schema.project_id), notice: 'Schema was successfully updated.' }
      else
        format.html { render :edit }
      end
    end
  end



  def destroy
    @schema.destroy
    respond_to do |format|
      format.html { redirect_to project_url(@schema.project_id), notice: 'Schema was successfully destroyed.' }
    end
  end




  private

    def set_schema
      @schema = Schema.find(params[:id])
    end

    def set_project
      @project = Project.friendly.find(params[:project_id])
    end


    def schema_params
      params.require(:schema).permit(:number, :identification, :reference, :name, :description, :author, :controller, :priority, :notes, :status, :cycle, :slug, :project_id)
    end

end

这是我的代码：

respond_to do |format|
  if @schema.update(schema_params)
    format.html { redirect_to project_url(@schema.project_id), notice: 'Schema was successfully updated.' }
  else
    format.html { render :edit }
  end

它适用于索引和显示页面，但更新、编辑和销毁时出现以下错误：

ActionController::UrlGenerationError in Projects::SchemasController#update

No route matches {:action=>"show", :controller=>"projects", :id=>nil} missing required keys: [:id]

谁能帮我弄清楚这是怎么回事？

【问题讨论】：

您介意分享您的 config/routes.rb 吗？

标签： ruby-on-rails ruby friendly-id

【解决方案1】：

您正在寻找的是嵌套路由。在这种情况下，您可以包含此路由声明：

resources :projects do
  resources :schemas
end

除了projects 的路由之外，此声明还将schemas 路由到SchemasController。 schema URL 需要 project:

/projects/:project_id/schemas/:id

这还将创建路由助手，例如 project_schemas_url 和 edit_project_schema_path。这些助手将Project 的实例作为第一个参数：project_schemas_url(@project)。

记住始终在现有的project 上实例化schemas，例如：

@project.schemas.build

【讨论】：