Nested resources (#189)

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+### Unreleased
+Features
+- Support for nested resources (https://github.com/varvet/godmin/pull/189)
+
 ### 1.4.0 - 2017-02-15
 Features
 - Support group queries in scopes and filters (https://github.com/varvet/godmin/pull/208)

README.md

@@ -24,6 +24,7 @@ Godmin differs from tools like [ActiveAdmin](http://activeadmin.info/) and [Rail
   - [Redirecting](#redirecting)
   - [Pagination](#pagination)
   - [Exporting](#exporting)
+  - [Nested resources](#nested-resources)
 - [Views](#views)
   - [Forms](#forms)
   - [Navigation](#navigation)
@@ -510,7 +511,7 @@ If you wish to change the number of resources per page, you can override the `pe
 
 ```ruby
 class ArticlesService
-  include Godmin::Resources::Service
+  include Godmin::Resources::ResourceService
 
   def per_page
     50
@@ -524,12 +525,36 @@ The `attrs_for_export` method in the service object makes it possible to mark at
 
 ```ruby
 class ArticlesService
-  include Godmin::Resources::Service
+  include Godmin::Resources::ResourceService
 
   attrs_for_export :id, :title, :created_at, :updated_at
 end
 ```
 
+### Nested resources
+
+Nested resources can be implemented by nesting your routes:
+
+```ruby
+resources :blogs do
+  resources :blog_posts
+end
+```
+
+This will set up scoping of the nested resource as well as correct links in the breadcrumb.
+
+If you want to add a link to the nested resource from the parent's show and edit pages, you can add the following to the service object:
+
+```ruby
+class BlogService
+  include Godmin::Resources::ResourceService
+
+  has_many :blog_posts
+end
+```
+
+Otherwise, simply add links as you see fit using partial overrides.
+
 ## Views
 
 It's easy to override view templates and partials in Godmin, both globally and per resource. All you have to do is place a file with an identical name in your `app/views` directory. For instance, to override the `godmin/resource/index.html.erb` template for all resources, place a file under `app/views/resource/index.html.erb`. If you only wish to override it for articles, place it instead under `app/views/articles/index.html.erb`.

app/views/godmin/resource/_breadcrumb.html.erb

@@ -1,12 +1,22 @@
 <div id="breadcrumb">
   <ol class="breadcrumb">
+    <% if @resource_parents %>
+      <% @resource_parents.each do |parent| %>
+        <li>
+          <%= link_to parent.class.model_name.human(count: 2), parent.class %>
+        </li>
+        <li>
+          <%= link_to parent.to_s, parent %>
+        </li>
+      <% end %>
+    <% end %>
     <% if action_name == "index" %>
       <li class="active">
         <%= @resource_class.model_name.human(count: 2) %>
       </li>
     <% else %>
       <li>
-        <%= link_to @resource_class.model_name.human(count: 2), @resource_class %>
+        <%= link_to @resource_class.model_name.human(count: 2), [*@resource_parents, @resource_class] %>
       </li>
       <li class="active">
         <% if @resource.new_record? %>
@@ -16,29 +26,7 @@
         <% end %>
       </li>
       <% if @resource.persisted? %>
-        <li class="dropdown pull-right">
-          <a href="#" data-toggle="dropdown" role="button">
-            <%= translate_scoped("actions.label") %> <span class="caret"></span>
-          </a>
-          <ul class="dropdown-menu">
-            <% if policy(@resource).show? && action_name != "show" %>
-              <li>
-                <%= link_to translate_scoped("actions.show"), @resource %>
-              </li>
-            <% end %>
-            <% if policy(@resource).edit? && action_name != "edit" %>
-              <li>
-                <%= link_to translate_scoped("actions.edit"), [:edit, @resource]  %>
-              </li>
-            <% end %>
-            <% if policy(@resource).destroy? %>
-              <li>
-                <%= link_to translate_scoped("actions.destroy"), @resource, method: :delete,
-                  data: { confirm: translate_scoped("actions.confirm_message") } %>
-              </li>
-            <% end %>
-          </ul>
-        </li>
+        <%= render partial: "breadcrumb_actions" %>
       <% end %>
     <% end %>
   </ol>

app/views/godmin/resource/_breadcrumb_actions.html.erb

@@ -0,0 +1,41 @@
+<li class="dropdown pull-right">
+  <a href="#" data-toggle="dropdown">
+    <%= translate_scoped("actions.label") %> <span class="caret"></span>
+  </a>
+  <ul class="dropdown-menu">
+    <% if policy(@resource).show? && action_name != "show" %>
+      <li>
+        <%= link_to translate_scoped("actions.show"), [*@resource_parents, @resource] %>
+      </li>
+    <% end %>
+    <% if policy(@resource).edit? && action_name != "edit" %>
+      <li>
+        <%= link_to translate_scoped("actions.edit"), [:edit, *@resource_parents, @resource]  %>
+      </li>
+    <% end %>
+    <% if policy(@resource).destroy? %>
+      <li>
+        <%= link_to translate_scoped("actions.destroy"), [*@resource_parents, @resource], method: :delete,
+          data: { confirm: translate_scoped("actions.confirm_message") } %>
+      </li>
+    <% end %>
+  </ul>
+</li>
+
+<% if @resource_service.has_many_map.present? %>
+  <li class="dropdown pull-right">
+    <a href="#" data-toggle="dropdown">
+      <%= translate_scoped("associations.label") %> <span class="caret"></span>
+    </a>
+    <ul class="dropdown-menu">
+      <% @resource_service.has_many_map.each do |name, options| %>
+        <% if policy(options[:class_name].constantize).index? %>
+          <li>
+            <%= link_to(options[:class_name].constantize.model_name.human(count: 2),
+              send("#{@resource_class.name.underscore}_#{name}_path", @resource)) %>
+          </li>
+        <% end %>
+      <% end %>
+    </ul>
+  </li>
+<% end %>

app/views/godmin/resource/_button_actions.html.erb

@@ -1,3 +1,3 @@
 <% if policy(@resource_service.build_resource({})).new? %>
-  <%= link_to t("helpers.submit.create", model: @resource_class.model_name.human), [:new, @resource_class.model_name.singular_route_key], class: "btn btn-default" %>
+  <%= link_to t("helpers.submit.create", model: @resource_class.model_name.human), [:new, *@resource_parents, @resource_class.model_name.singular_route_key], class: "btn btn-default" %>
 <% end %>

app/views/godmin/resource/columns/_actions.html.erb

@@ -2,23 +2,23 @@
   <% if policy(resource).show? %>
     <%= link_to(
       translate_scoped("actions.show"),
-      resource,
+      [*@resource_parents, resource],
       class: "btn btn-default",
       title: translate_scoped("actions.show_title", resource: resource)
     ) %>
   <% end %>
   <% if policy(resource).edit? %>
     <%= link_to(
       translate_scoped("actions.edit"),
-      [:edit, resource],
+      [:edit, *@resource_parents, resource],
       class: "btn btn-default",
       title: translate_scoped("actions.edit_title", resource: resource)
     ) %>
   <% end %>
   <% if policy(resource).destroy? %>
     <%= link_to(
       translate_scoped("actions.destroy"),
-      resource,
+      [*@resource_parents, resource],
       method: :delete,
       class: "btn btn-default",
       title: translate_scoped("actions.destroy_title", resource: resource),

app/views/godmin/resource/show.html.erb

@@ -1,6 +1,6 @@
 <%= render partial: "breadcrumb" %>
 
-<table class="table table-striped">
+<table class="table">
   <% @resource_service.attrs_for_show.each do |attr| %>
     <tr>
       <th><%= @resource_class.human_attribute_name(attr) %></th>

config/locales/en.yml

@@ -25,6 +25,8 @@ en:
       confirm_message: Are you sure?
       export: Export
       export_as: As
+    associations:
+      label: Nested resources
     sessions:
       sign_in: Sign in
       sign_out: Sign out

config/locales/pt-BR.yml

@@ -25,6 +25,8 @@ pt-BR:
       confirm_message: Você tem certeza?
       export: Exportar
       export_as: Como
+    associations:
+      label: Nested resources
     sessions:
       sign_in: Entrar
       sign_out: Sair

config/locales/sv.yml

@@ -25,6 +25,8 @@ sv:
       confirm_message: Är du säker?
       export: Exportera
       export_as: Som
+    associations:
+      label: Nästlade resurser
     sessions:
       sign_in: Logga in
       sign_out: Logga ut

lib/godmin/helpers/batch_actions.rb

@@ -6,7 +6,7 @@ def batch_action_link(name, options)
 
         link_to(
           translate_scoped("batch_actions.labels.#{name}", default: name.to_s.titleize),
-          @resource_class,
+          [*@resource_parents, @resource_class],
           method: :patch,
           class: "btn btn-default hidden",
           data: {

lib/godmin/helpers/forms.rb

@@ -2,7 +2,11 @@ module Godmin
   module Helpers
     module Forms
       def form_for(record, options = {}, &block)
-        super(record, { builder: FormBuilders::FormBuilder, inline_errors: false }.merge(options), &block)
+        super(record, {
+          url: [*@resource_parents, record],
+          builder: FormBuilders::FormBuilder,
+          inline_errors: false
+        }.merge(options), &block)
       end
     end
   end

lib/godmin/resources/resource_controller.rb

@@ -17,6 +17,7 @@ module ResourceController
 
         before_action :set_resource_service
         before_action :set_resource_class
+        before_action :set_resource_parents
         before_action :set_resources, only: :index
         before_action :set_resource, only: [:show, :new, :edit, :create, :update, :destroy]
       end
@@ -83,6 +84,10 @@ def set_resource_class
         @resource_class = resource_class
       end
 
+      def set_resource_parents
+        @resource_parents = resource_parents
+      end
+
       def set_resources
         @resources = resources
         authorize(@resources) if authorization_enabled?
@@ -98,17 +103,31 @@ def resource_service_class
       end
 
       def resource_service
+        resource_service = resource_service_class.new
+
         if authentication_enabled?
-          resource_service_class.new(admin_user: admin_user)
-        else
-          resource_service_class.new
+          resource_service.options[:admin_user] = admin_user
+        end
+
+        if resource_parents.present?
+          resource_service.options[:resource_parent] = resource_parents.last
         end
+
+        resource_service
       end
 
       def resource_class
         @resource_service.resource_class
       end
 
+      def resource_parents
+        params.to_unsafe_h.each_with_object([]) do |(name, value), parents|
+          if name =~ /(.+)_id$/
+            parents << $1.classify.constantize.find(value)
+          end
+        end
+      end
+
       def resources
         @resource_service.resources(params)
       end
@@ -151,11 +170,11 @@ def redirect_after_update
       end
 
       def redirect_after_save
-        @resource
+        [*@resource_parents, @resource]
       end
 
       def redirect_after_destroy
-        resource_class.model_name.route_key.to_sym
+        [*@resource_parents, resource_class.model_name.route_key.to_sym]
       end
 
       def redirect_flash_message

lib/godmin/resources/resource_service.rb

@@ -1,3 +1,4 @@
+require "godmin/resources/resource_service/associations"
 require "godmin/resources/resource_service/batch_actions"
 require "godmin/resources/resource_service/filters"
 require "godmin/resources/resource_service/ordering"
@@ -9,6 +10,7 @@ module Resources
     module ResourceService
       extend ActiveSupport::Concern
 
+      include Associations
       include BatchActions
       include Filters
       include Ordering
@@ -21,7 +23,6 @@ def initialize(options = {})
         @options = options
       end
 
-      # TODO: should this raise its own error?
       def resource_class
         @options[:resource_class] || resource_class_name.constantize
       end
@@ -31,7 +32,11 @@ def resource_class_name
       end
 
       def resources_relation
-        resource_class.all
+        if options[:resource_parent].present?
+          resource_class.where(options[:resource_parent].class.name.underscore => options[:resource_parent])
+        else
+          resource_class.all
+        end
       end
 
       def resources(params)

lib/godmin/resources/resource_service/associations.rb

@@ -0,0 +1,23 @@
+module Godmin
+  module Resources
+    module ResourceService
+      module Associations
+        extend ActiveSupport::Concern
+
+        delegate :has_many_map, to: "self.class"
+
+        module ClassMethods
+          def has_many_map
+            @has_many_map ||= {}
+          end
+
+          def has_many(attr, options = {})
+            has_many_map[attr] = {
+              class_name: attr.to_s.singularize.classify
+            }.merge(options)
+          end
+        end
+      end
+    end
+  end
+end

test/dummy/app/controllers/comments_controller.rb

@@ -0,0 +1,3 @@
+class CommentsController < ApplicationController
+  include Godmin::Resources::ResourceController
+end

test/dummy/app/models/article.rb

@@ -1,5 +1,6 @@
 class Article < ActiveRecord::Base
   belongs_to :admin_user
+  has_many :comments
 
   def non_orderable_column
     "Not orderable"

test/dummy/app/models/comment.rb

@@ -0,0 +1,7 @@
+class Comment < ActiveRecord::Base
+  belongs_to :article
+
+  def to_s
+    title
+  end
+end