Dropdown to adjust page size. Fixes #1195

Author: fbacall

app/assets/javascripts/application.js

@@ -50,6 +50,15 @@ function redirect_to_sort_url(){
     window.location.replace(url.toString());
 }
 
+function apply_per_page(){
+    url = new URL(window.location.href);
+    url.searchParams.set(
+        "per_page",
+        $("#per_page").val()
+    );
+    window.location.replace(url.toString());
+}
+
 function redirect_with_updated_search(param, paramVal) {
     url = new URL(window.location.href);
     // special case for empty range types

app/assets/stylesheets/application.scss

@@ -418,10 +418,21 @@ ul.unstyled {
 }
 
 .search-results-count {
-  margin-right: 5px;
+  margin-right: 1em;
   display: inline-block
 }
 
+.search-results-per-page {
+  display: inline-block;
+
+  select {
+    border: none;
+    padding: 0;
+    background: transparent;
+    border-bottom: 1px dashed $text-color;
+  }
+}
+
 .index-display-options {
   margin: 5px 0;
 }

app/controllers/concerns/searchable_index.rb

@@ -1,5 +1,8 @@
 # The concern for searchable index
 module SearchableIndex
+  DEFAULT_PAGE_SIZE = 10
+  PER_PAGE_OPTIONS = [10, 20, 50, 100]
+
   extend ActiveSupport::Concern
 
   included do
@@ -19,7 +22,7 @@ def count
   def fetch_resources
     if TeSS::Config.solr_enabled
       page = page_param.blank? ? 1 : page_param.to_i
-      per_page = per_page_param.blank? ? 10 : per_page_param.to_i
+      per_page = per_page_param.blank? ? DEFAULT_PAGE_SIZE : per_page_param.to_i
 
       @search_results = @model.search_and_filter(current_user, @search_params, @facet_params,
                                     page: page, per_page: per_page, sort_by: @sort_by)

app/helpers/application_helper.rb

@@ -708,4 +708,9 @@ def omniauth_login_link(provider, config)
       method: :post
     )
   end
+
+  def per_page_options_for_select
+    options_for_select(SearchableIndex::PER_PAGE_OPTIONS.map { |k| [k, k] },
+                       params[:per_page].presence || SearchableIndex::DEFAULT_PAGE_SIZE)
+  end
 end

app/views/search/common/_search_panel.html.erb

@@ -27,6 +27,10 @@
         <div class="search-results-count">
           <%= pluralize(resources.total, resource_type.model_name.human.downcase ) %> found
         </div>
+        <div class="search-results-per-page form-inline pull-right">
+            <label for="per_page"><%= t('sidebar.per_page') %></label>
+            <%= select_tag('per_page', per_page_options_for_select, onchange: 'apply_per_page()', class: 'font-size-sm') %>
+        </div>
       <% end %>
     </div>
   </div>

config/locales/en.yml

@@ -910,6 +910,7 @@ en:
       values:
         show_hidden: 'Show hidden items'
         hide_hidden: 'Hide hidden items'
+    per_page: 'Results per page: '
   collections:
     show:
       curate_materials: "Curate materials"