AJAX_ify StockArticle manipulation; Introduce publish/subscribe pattern for DOM updates

app/controllers/stockit_controller.rb

@@ -5,29 +5,61 @@ class StockitController < ApplicationController
         order('suppliers.name, article_categories.name, articles.name')
   end
   
+  def index_on_stock_article_create # See publish/subscribe design pattern in /doc.
+    @stock_article = StockArticle.find(params[:id])
+    
+    render :layout => false
+  end
+
+  def index_on_stock_article_update # See publish/subscribe design pattern in /doc.
+    @stock_article = StockArticle.find(params[:id])
+    
+    render :layout => false
+  end
+
+  # three possibilites to fill a new_stock_article form
+  # (1) start from blank or use params
   def new
-    @stock_article = StockArticle.new
+    @stock_article = StockArticle.new(params[:stock_article])
+
+    render :layout => false
+  end
+  
+  # (2) StockArticle as template
+  def copy
+    @stock_article = StockArticle.find(params[:stock_article_id]).dup
+    
+    render :layout => false
+  end
+  
+  # (3) non-stock Article as template
+  def derive
+    @stock_article = Article.find(params[:old_article_id]).becomes(StockArticle).dup
+    
+    render :layout => false
   end
 
   def create
     @stock_article = StockArticle.new(params[:stock_article])
-    if @stock_article.save
-      redirect_to stock_articles_path, :notice => I18n.t('stockit.stock_create.notice')
+    if @stock_article.valid? and @stock_article.save
+      render :layout => false
     else
-      render :action => 'new'
+      render :action => 'new', :layout => false
     end
   end
 
   def edit
     @stock_article = StockArticle.find(params[:id])
+    
+    render :layout => false
   end
 
   def update
     @stock_article = StockArticle.find(params[:id])
     if @stock_article.update_attributes(params[:stock_article])
-      redirect_to stock_articles_path, :notice => I18n.t('stockit.stock_update.notice')
+      render :layout => false
     else
-      render :action => 'edit'
+      render :action => 'edit', :layout => false
     end
   end
 
@@ -36,9 +68,15 @@ class StockitController < ApplicationController
     @stock_changes = @stock_article.stock_changes.order('stock_changes.created_at DESC')
   end
 
+  def show_on_stock_article_update # See publish/subscribe design pattern in /doc.
+    @stock_article = StockArticle.find(params[:id])
+    
+    render :layout => false
+  end
+
   def destroy
-    @article = StockArticle.find(params[:id])
-    @article.mark_as_deleted
+    @stock_article = StockArticle.find(params[:id])
+    @stock_article.mark_as_deleted
     render :layout => false
   rescue => error
     render :partial => "destroy_fail", :layout => false,

app/helpers/stockit_helper.rb

@@ -14,4 +14,13 @@ module StockitHelper
       link_to t('.stock_taking'), stock_taking_path(stock_change.stock_taking)
     end
   end
+  
+  def stock_article_price_hint(stock_article)
+    t('simple_form.hints.stock_article.edit_stock_article.price',
+      :stock_article_copy_link => link_to(t('.copy_stock_article'),
+        stock_article_copy_path(stock_article),
+        :remote => true
+      )
+    )
+  end
 end

app/views/stockit/_form.html.haml

@@ -1,9 +1,12 @@
-= simple_form_for stock_article, :validate => true do |f|
+= simple_form_for stock_article, remote: true, :validate => true do |f|
+  .modal-header
+    = link_to t('ui.marks.close').html_safe, '#', class: 'close', data: {dismiss: 'modal'}
+    %h3= title
+  .modal-body
     = f.association :supplier
     = f.input :name
     = f.input :unit
     = f.input :note
-
     - if stock_article.new_record?
       = f.input :price
       = f.input :tax, :wrapper => :append do
@@ -11,8 +14,8 @@
         %span.add-on %
       = f.input :deposit
     - else
-    = f.input :price, :input_html => {:disabled => 'disabled'}, :hint => t('.price_hint')
+      = f.input :price, :input_html => {:disabled => 'disabled'}, :hint => stock_article_price_hint(stock_article).html_safe
     = f.association :article_category
-  .form-actions
-    = f.submit class: 'btn'
-    = link_to t('ui.or_cancel'), stock_articles_path
+  .modal-footer
+    = link_to t('ui.close'), '#', class: 'btn', data: {dismiss: 'modal'}
+    = f.submit :class => 'btn btn-primary', 'data-disable-with' => t('ui.please_wait')

app/views/stockit/_stock_article.html.haml

@@ -0,0 +1,14 @@
+%tr{:class => stock_article_classes(stock_article), :id => "stockArticle-#{stock_article.id}"}
+  %td= link_to stock_article.name, stock_article
+  %td= stock_article.quantity
+  %td= stock_article.quantity - stock_article.quantity_available
+  %th= stock_article.quantity_available
+  %td= stock_article.unit
+  %td= stock_article.price
+  %td= number_to_percentage stock_article.tax
+  %td= link_to stock_article.supplier.name, stock_article.supplier
+  %td= stock_article.article_category.name
+  %td
+    = link_to t('ui.edit'), edit_stock_article_path(stock_article), remote: true, class: 'btn btn-mini'
+    = link_to t('ui.delete'), stock_article, :method => :delete, :confirm => t('.confirm_delete', :name => stock_article.name),
+      class: 'btn btn-mini btn-danger', :remote => true

app/views/stockit/_stock_article_details.html.haml

@@ -0,0 +1,26 @@
+#stockArticleDetails
+  %dl.dl-horizontal
+    %dt= heading_helper(StockArticle, :supplier)
+    %dd= link_to stock_article.supplier.name, stock_article.supplier
+    %dt= heading_helper(StockArticle, :name)
+    %dd= stock_article.name
+    %dt= heading_helper(StockArticle, :unit)
+    %dd= stock_article.unit
+    %dt= heading_helper(StockArticle, :price)
+    %dd= number_to_currency stock_article.price
+    %dt= heading_helper(StockArticle, :tax)
+    %dd= number_to_percentage stock_article.tax
+    %dt= heading_helper(StockArticle, :deposit)
+    %dd= number_to_currency stock_article.deposit
+    %dt= heading_helper(StockArticle, :fc_price)
+    %dd= number_to_currency stock_article.fc_price
+    %dt= heading_helper(StockArticle, :article_category)
+    %dd= stock_article.article_category.name
+    %dt= heading_helper(StockArticle, :note)
+    %dd= stock_article.note
+    %dt= heading_helper(StockArticle, :quantity)
+    %dd= stock_article.quantity
+    %dt= heading_helper(StockArticle, :quantity_available)
+    %dd= stock_article.quantity_available
+  .form-actions
+    = link_to t('ui.edit'), edit_stock_article_path(stock_article), remote: true, class: 'btn'

app/views/stockit/copy.js.erb

@@ -0,0 +1,9 @@
+$('#modalContainer').html('<%= j(render(
+  :partial => "form",
+  :locals => {
+    :title => t('.title'),
+    :stock_article => @stock_article
+  }
+)) %>');
+
+$('#modalContainer').modal();

app/views/stockit/create.js.erb

@@ -0,0 +1,15 @@
+$('div.container-fluid').prepend('<%= j(render(
+  :partial => 'shared/alert_success',
+  :locals => {
+    :alert_message => t('.notice', :name => @stock_article.name)
+  }
+)) %>');
+
+// Publish database changes.
+// See publish/subscribe design pattern in /doc.
+$(document).trigger({
+  type: 'StockArticle#create',
+  stock_article_id: <%= @stock_article.id %>
+});
+
+$('#modalContainer').modal('hide');

app/views/stockit/destroy.js.erb

@@ -0,0 +1,13 @@
+$('div.container-fluid').prepend('<%= j(render(
+  :partial => 'shared/alert_success',
+  :locals => {
+    :alert_message => t('.notice', :name => @stock_article.name)
+  }
+)) %>');
+
+// Publish database changes.
+// See publish/subscribe design pattern in /doc.
+$(document).trigger({
+  type: 'StockArticle#destroy',
+  stock_article_id: <%= @stock_article.id %>
+});

app/views/stockit/destroy.js.haml

@@ -1,8 +0,0 @@
--# please polish the following line if you know how, same in partial _destroy_fail
-var successDiv = $('<div class="alert fade in alert-success"><a class="close" data-dismiss="alert" href="#">#{escape_javascript(t('ui.marks.close').html_safe)}</a></div>');
-
-successDiv.append(document.createTextNode('#{escape_javascript(t('.notice', name: @article.name))}'));
-$('div.container-fluid').prepend(successDiv);
-
-$('#stockArticle-#{@article.id}').remove();
--# WARNING: Do not use a simple .fadeOut() above, because it conflicts with the show/hide function of unavailable articles.

app/views/stockit/edit.html.haml

@@ -1,3 +0,0 @@
-- title t('.title')
-
-= render :partial => 'form', :locals => {:stock_article => @stock_article}

app/views/stockit/edit.js.erb

@@ -0,0 +1,9 @@
+$('#modalContainer').html('<%= j(render(
+  :partial => "form",
+  :locals => {
+    :title => t('.title'),
+    :stock_article => @stock_article
+  }
+)) %>');
+
+$('#modalContainer').modal();

app/views/stockit/index.html.haml

@@ -3,6 +3,30 @@
   :javascript
     $(function() {
       $('tr.unavailable').hide();
+      
+      // Subscribe to database changes.
+      // See publish/subscribe design pattern in /doc.
+      $(document).on('StockArticle#create', function(e) {
+        $.ajax({
+          url: '#{index_on_stock_article_create_stock_articles_path}',
+          type: 'get',
+          data: {id: e.stock_article_id},
+          contentType: 'application/json; charset=UTF-8'
+        });
+      });
+      
+      $(document).on('StockArticle#destroy', function(e) {
+        $('#stockArticle-' + e.stock_article_id).remove();
+      });
+      
+      $(document).on('StockArticle#update', function(e) {
+        $.ajax({
+          url: '#{index_on_stock_article_update_stock_articles_path}',
+          type: 'get',
+          data: {id: e.stock_article_id},
+          contentType: 'application/json; charset=UTF-8'
+        });
+      });
     })
 
 .well.well-small
@@ -17,7 +41,7 @@
     .btn-group
       = link_to_if @current_user.role_orders?, t('.order_online'), new_order_path(supplier_id: 0),
         class: 'btn', class: 'btn btn-primary'
-      = link_to t('.new_stock_article'), new_stock_article_path, class: 'btn'
+      = link_to t('.new_stock_article'), new_stock_article_path, remote: true, class: 'btn'
       = link_to t('.new_stock_taking'), new_stock_taking_path, class: 'btn'
       = link_to t('.show_stock_takings'), stock_takings_path, class: 'btn'
 
@@ -42,22 +66,9 @@
       %th= t '.article.supplier'
       %th= t '.article.category'
       %th
-  %tbody
-    - for article in @stock_articles
-      %tr{:class => stock_article_classes(article), :id => "stockArticle-#{article.id}"}
-        %td= link_to article.name, article
-        %td= article.quantity
-        %td= article.quantity - article.quantity_available
-        %th= article.quantity_available
-        %td= article.unit
-        %td= article.price
-        %td= number_to_percentage article.tax
-        %td= link_to article.supplier.name, article.supplier
-        %td= article.article_category.name
-        %td
-          = link_to t('ui.edit'), edit_stock_article_path(article), class: 'btn btn-mini'
-          = link_to t('ui.delete'), article, :method => :delete, :confirm => t('.confirm_delete'),
-            class: 'btn btn-mini btn-danger', :remote => true
+  %tbody#articles-tbody
+    - for stock_article in @stock_articles
+      = render :partial => 'stock_article', :locals => {:stock_article => stock_article}
 %p
   = t '.stock_worth'
   = number_to_currency StockArticle.stock_value

app/views/stockit/index_on_stock_article_create.js.erb

@@ -0,0 +1,12 @@
+// Handle more advanced DOM update after AJAX database manipulation.
+// See publish/subscribe design pattern in /doc.
+(function() {
+  var stock_article_row = $('<%= j(render(
+    :partial => 'stock_article',
+    :locals => {
+      :stock_article => @stock_article
+    }
+  )) %>');
+
+  $('#articles-tbody').prepend(stock_article_row);
+})();

app/views/stockit/index_on_stock_article_update.js.erb

@@ -0,0 +1,12 @@
+// Handle more advanced DOM update after AJAX database manipulation.
+// See publish/subscribe design pattern in /doc.
+(function() {
+  var stock_article_row = $('<%= j(render(
+    :partial => 'stock_article',
+    :locals => {
+      :stock_article => @stock_article
+    }
+  )) %>');
+
+  $('#stockArticle-<%= @stock_article.id %>').replaceWith(stock_article_row);
+})();

app/views/stockit/new.html.haml

@@ -1,22 +0,0 @@
-- title t('.title')
-
-- content_for :head do
-  :javascript
-    $(function() {
-      $('#article_search').autocomplete({
-          source: '#{articles_search_stock_articles_path}',
-          select: function(e, ui) {
-            alert(ui.item.value);
-            //location.href = '#{nil}' + ui.item.value;
-          }
-        });
-    })
-
-
-/
-  TODO: Fix this
-  %p
-  = t '.search_text'
-  = text_field_tag 'article_search'
-#stock_article_form
-  = render :partial => 'form', :locals => {:stock_article => @stock_article}

app/views/stockit/new.js.erb

@@ -0,0 +1,9 @@
+$('#modalContainer').html('<%= j(render(
+  :partial => "form",
+  :locals => {
+    :title => t('.title'),
+    :stock_article => @stock_article
+  }
+)) %>');
+
+$('#modalContainer').modal();

app/views/stockit/show.html.haml

@@ -1,32 +1,22 @@
 - title @stock_article.name
+- content_for :javascript do
+  :javascript
+    $(function() {
+      // Subscribe to database changes.
+      // See publish/subscribe design pattern in /doc.
+      $(document).on('StockArticle#update', function(e) {
+        $.ajax({
+          url: '#{show_on_stock_article_update_stock_articles_path}',
+          type: 'get',
+          data: {id: e.stock_article_id},
+          contentType: 'application/json; charset=UTF-8'
+        });
+      });
+    });
 
 .row-fluid
   .span6
-    %dl.dl-horizontal
-      %dt= StockArticle.human_attribute_name 'supplier'
-      %dd= link_to @stock_article.supplier.name, @stock_article.supplier
-      %dt= StockArticle.human_attribute_name 'name'
-      %dd= @stock_article.name
-      %dt= StockArticle.human_attribute_name 'unit'
-      %dd= @stock_article.unit
-      %dt= StockArticle.human_attribute_name 'price'
-      %dd= number_to_currency @stock_article.price
-      %dt= StockArticle.human_attribute_name 'tax'
-      %dd= number_to_percentage @stock_article.tax
-      %dt= StockArticle.human_attribute_name 'deposit'
-      %dd= number_to_currency @stock_article.deposit
-      %dt= StockArticle.human_attribute_name 'fc_price'
-      %dd= number_to_currency @stock_article.fc_price
-      %dt= StockArticle.human_attribute_name 'article_category'
-      %dd= @stock_article.article_category.name
-      %dt= StockArticle.human_attribute_name 'note'
-      %dd= @stock_article.note
-      %dt= StockArticle.human_attribute_name 'quantity'
-      %dd= @stock_article.quantity
-      %dt= StockArticle.human_attribute_name 'quantity_available'
-      %dd= @stock_article.quantity_available
-    .form-actions
-      = link_to t('ui.edit'), edit_stock_article_path(@stock_article), class: 'btn'
+    = render :partial => 'stock_article_details', :locals => {:stock_article => @stock_article}
   
   .span6
     %h2= t('.stock_changes')

app/views/stockit/show_on_stock_article_update.js.erb

@@ -0,0 +1,13 @@
+// Handle more advanced DOM update after AJAX database manipulation.
+// See publish/subscribe design pattern in /doc.
+(function() {
+  var stock_article_details = $('<%= j(render(
+    :partial => 'stock_article_details',
+    :locals => {
+      :stock_article => @stock_article
+    }
+  )) %>');
+
+  $('#stockArticleDetails').replaceWith(stock_article_details);
+  $('h1').first().text('<%= j(@stock_article.name) %>');
+})();

app/views/stockit/update.js.erb

@@ -0,0 +1,15 @@
+$('div.container-fluid').prepend('<%= j(render(
+  :partial => 'shared/alert_success',
+  :locals => {
+    :alert_message => t('.notice', :name => @stock_article.name)
+  }
+)) %>');
+
+// Publish database changes.
+// See publish/subscribe design pattern in /doc.
+$(document).trigger({
+  type: 'StockArticle#update',
+  stock_article_id: <%= @stock_article.id %>
+});
+
+$('#modalContainer').modal('hide');

config/locales/en.yml

@@ -1348,7 +1348,7 @@ en:
         units_to_order: If you change the total amount of delivered units, you also have to change individual group amounts by clicking on the article name. They will not be automatically recalculated and so ordergroups may be accounted for articles that were not delivered!
         update_current_price: Also update the price of the current order
       stock_article:
-        copy_stock_article:
+        copy:
           name: Please modify
         edit_stock_article:
           price: <ul><li>Price changes are forbidden.</li><li>If necessary, %{stock_article_copy_link}.</li></ul>
@@ -1421,8 +1421,10 @@ en:
   stockit:
     check:
       not_empty: ! '%{name} could not be deleted, the inventory is not zero.'
+    create:
+      notice: New stock article »%{name}« was created.
     destroy:
-      notice: Article %{name} was deleted.
+      notice: Article »%{name}« was deleted.
     edit:
       title: Edit stock articles
     form:
@@ -1461,10 +1463,10 @@ en:
       reason: Reason
       stock_changes: Stock quantity changes
       stock_taking: Inventory
-    stock_create:
-      notice: Stock article was created.
-    stock_update:
-      notice: Stock article was saved.
+    stock_article:
+      confirm_delete: Are you sure you want to delete the stock article »%{name}«?
+    update:
+      notice: Stock article »%{name}« was saved.
   suppliers:
     create:
       notice: Supplier was created

config/routes.rb

@@ -86,9 +86,15 @@ Foodsoft::Application.routes.draw do
     end
 
     resources :stock_articles, :to => 'stockit' do
+      get :copy
       collection do
         get :articles_search
         get :fill_new_stock_article_form
+        
+        get :index_on_stock_article_create
+        get :index_on_stock_article_update
+        
+        get :show_on_stock_article_update
       end
     end
 

doc/design_patterns/publish_subscribe.md

@@ -0,0 +1,33 @@
+# Publish/subscribe pattern
+## Handling DOM updates after AJAX database manipulation
+
+As an example, let us consider the manipulation (create, update...) of `StockArticles`. This can be done in different views, e.g., `stock_articles/index`, `stock_articles/show` and `deliveries/_form` through modals using AJAX requests. As an advantage of the AJAX technique, the user does not need to reload the entire page. However, (after the update of the `StockArticle` in the database) it is generally required to update the DOM in the current view such that the page properly reacts to the asynchronous actions.
+
+The process can be divided in two steps: **1.** AJAX database manipulation and **2.** DOM updates for the particular view. The crucial point is the coupling of the two steps since the controller for the first step offers the same functionality to all views and does not need to know anything about the current view.
+
+1. AJAX database manipulation
+    1. Example: current view `deliveries/_form` offers a link for the AJAX action `StockArticle#new`. This opens a modal filled with `stock_articles/_form`.
+    2. AJAX form post addresses the `StockArticle#create` action which handles the database manipulation.
+    3. The database manipulation is finished by the rendering of, e.g., `stock_articles/create.js.erb`. The key task there is to **publish** the database changes by calling `trigger`, i.e.,
+        $(document).trigger({
+          type: 'StockArticle#create',
+          stock_article_id: <%= @stock_article.id %>
+        });
+2. DOM updates for the particular view
+    1. Each view has the opportunity to **subscribe** to particular events of the previous step. A very simple example is the update of the `stock_articles/index` view after `StockArticle#destroy`:
+        $(document).on('StockArticle#destroy', function(e) {
+          $('#stockArticle-' + e.stock_article_id).remove();
+        });
+    
+    However, in most of the situations you will like to use the full power of the MVC framework in order to read new data from the database and render some partial. Let us consider this slightly more advanced case in the following.
+    
+    The view `stock_articles/index` could listen (amongst others) to `StockArticle#create` like this:
+        $(document).on('StockArticle#create', function(e) {
+          $.ajax({
+            url: '#{index_on_stock_article_create_stock_articles_path}',
+            type: 'get',
+            data: {id: e.stock_article_id},
+            contentType: 'application/json; charset=UTF-8'
+          });
+        });
+    2. The action `StockArticles#index_on_stock_article_create` is a special helper action to handle DOM updates of the `stock_articles/index` view after the creation of a new `StockArticle` with the given `id`.