The Flexibility of Drupal 8
A presentation at NYC Drupal Camp in in New York, NY, USA by Michael Miles
THE FLEXIBILITY OF DRUPAL 8
MIKE MILES Genuine (wearegenuine.com) All the internet places: mikemiles86
FLEXIBLITY
WHAT MAKES DRUPAL FLEXIBLE Modular design Decoupled systems Open Source nature
WHY FLEXIBLITY IS IMPORTANT Make Drupal do what you want No “right way”, just a “right for me” way Adjust for skillsets, time and budget
THREE AREAS OF FLEXIBILITY The Interface Display Layer Data Layer
FOCUS OF THIS SESSION To prove the flexiblity of Drupal To demostrate abilities of all skillsets To discuss considerations and limitations
THE DEMO Drupal 8.1.3 Standard Install Profile Change menu tabs using 8 different methods
THE BEFORE A plain Drupal 8 install with menu menu links before altering.
THE AFTER Drupal 8 main menu a er altering 8 different ways.
#1 DRUPAL CORE
THE “CLICKING BUTTONS” METHOD “Easy” and “Quick” Little to No dev skills needed Capabilities are limited
Use Drupal core to edit a main menu link. Limited to changing the title and the destination.
The first menu link has been altered using only Drupal core.
#2 MODULES
THE EXTEND CORE METHOD Requires time for research. Can’t find one? Can build your own (Dev skills needed) Requires long term maintence
Look for modules on Drupal.org to see if there is one that meets your needs. Found the Menu Links Attributes module for Drupal 8.
Many ways to download and enable modules. Will use the core interface to enable the Menu Links Attributes module a er downloading.
When editing a menu link, now have more attributes available to set.
Menu Links Attributes module requires some technial (YAML) knowledge to customize
1 attributes: 2 class: 3 label: ” 4 description: ” 5 target: 6 label: ” 7 description: ” 8 options: 9 _blank: ‘New window (_blank)’ 10 _self: ‘Same window (_self)’ 11 style: 12 label: ” 13 description: ” 14 _core: 15 default_config_hash: 9nRDOclwSlz2Os9mJXM1LXNbV2q-bADV0zipiWPXymk Add a new configurable ‘style’ attribute (lines 11-13) to the YAML
A er saving configuration, now able to add inline style to menu links
Using a contrib module allowed for altering the style of the “Modules” main menu link.
#3 TWIG TEMPLATES
THE ALTER MARKUP METHOD Almost everything is templated Need to know HTML and/or Twig Requires a custom theme
Can use Twig debug to learn which template the main menu uses.
1 <!— THEME DEBUG —> 2 <!— THEME HOOK: ‘menu__main’ —> 3 <!— FILE NAME SUGGESTIONS: 4 * menu—main.html.twig 5 x menu.html.twig 6 —> 7 <!— BEGIN OUTPUT from ‘core/themes/classy/templates/navigation/menu.html.twig’ —> 8 <ul class=”clearfix menu”> 9 <!— // … —> 10 <li class=”menu-item”> 11 <a href=”/node/3” data-drupal-link-system-path=”node/3”>Twig</a> 12 </li> 13 <!— // … —> 14 </ul> 15 <!— END OUTPUT from ‘core/themes/classy/templates/navigation/menu.html.twig’ Twig debug tells the available template names to override current template.
Create a custom theme (flex_theme), to override the menu—main.html.twig template.
1 {# … #} 2 {% if items %} 3 {# … #} 4 {% for item in items %} 5 {# … #} 6 <li{{ item.attributes.addClass(classes) }}> 7 {% if item.title == ‘Twig’ %} 8 {% set style = ‘background:#0F0;color:#F00’ %} 9 {{ link(item.title ~ ’ Alt’, item.url, { ‘style’: style }) }} 10 {% else %} 11 {{ link(item.title, item.url) }} 12 {% endif %} 13 {# … #} 14 </li> 15 {% endfor %} 16 </ul> 17 {% endif %} flex_theme/templates/menu—main.html.twig Add logic to twig template (lines 7-12) to check title of current link and alter the styling.
Enabling the new theme as default so that Drupal will use the custom twig template for output.
Result of using a custom theme with template to alter “Twig” menu link.
#4 CSS
THE ALTER DISPLAY METHOD Target any element on the “page” Need to know CSS and how to add a library Requires a custom theme or module
Will add some custom styling to existing custom theme (flex_theme)
1 .menu—main .menu li:nth-child(5) a { 2 background: #0000FF; 3 color: #FFF; 4 } themes/flex_theme/css/menu_alter.css Use custom CSS to target the 5th item in the main menu
1 menu-alter: 2 version: VERSION 3 css: 4 component: 5 css/menu_alter.css: {} themes/flex_theme/flex_theme.libraries.yml Custom CSS and JavaScript need to be added to a custom library. Custom libraries are defined in a *.libraries.yml file.
1 2 3 4 5 6 7 8 9 name: Flex Theme type: theme description: An theme to demo the flexibility of Drupal 8. package: Core version: VERSION core: 8.x base theme: bartik libraries: - flex_theme/menu-alter themes/flex_theme/flex_theme.info.yml Add custom library as a dependency of the theme in the *.info.yml file. Drupal will include this library on any page where this theme is used.
The “CSS” menu link has been altered using custom CSS. Only able to alter the display of menu item.
#5 JAVASCRIPT
THE DOM MANIPULATION METHOD Change based on actions Need to know JavaScript and how to add a library Dependent on client browser, delay in execution
Will add new JavaScript and CSS to custom theme to alter data using custom JavaScript.
1 (function ($, Drupal) { 2 “use strict”; 3 Drupal.behaviors.flexThemeMenuAlterMain = { 4 attach: function (context) { 5 $(‘.menu—main ul.menu li a’).each(function(){ 6 if ($(this).attr(‘href’) == ‘/node/5’) { 7 $(this).addClass(‘yellow-menu’); 8 $(this).attr(‘style’, ‘color: #000;’); 9 $(this).attr(‘target’, ‘_blank’); 10 $(this).text($(this).text() + Drupal.t(’ Alt’)); 11 } 12 }); 13 } 14 } 15 })(jQuery, Drupal); themes/flex_theme/js/menu_alter_main.js Write a Drupal Behaviour that will trigger whenever the DOM loads. Target a specific menu item to change value and add a custom class.
1 .yellow-menu { 2 background: #FFFF00; 3 } themes/flex_theme/css/menu_alter_main.css Add some basic CSS for to a custom class name.
1 menu-alter: 2 version: VERSION 3 css: 4 component: 5 css/menu_alter.css: {} 6 menu-alter-main: 7 version: VERSION 8 css: 9 component: 10 css/menu_alter_main.css: {} 11 js: 12 js/menu_alter_main.js: {} 13 dependencies: 14 - core/jquery 15 - core/jquery.once 16 - core/drupal themes/flex_theme/flex_theme.libraries.yml Add a second library to libraries.yml file. A Liibrary can define both CSS and JS files to include, as well as, any dependencies on other libraries.
1 {{ attach_library(‘flex_theme/menu-alter-main’) }} 2 {# … #} 3 {% if items %} 4 {# … #} 5 {% for item in items %} 6 {# … #} 7 <li{{ item.attributes.addClass(classes) }}> 8 {% if item.title == ‘Twig’ %} 9 {% set style = ‘background:#0F0;color:#F00’ %} 10 {{ link(item.title ~ ’ Alt’, item.url, { ‘style’: style }) }} 11 {% else %} 12 {{ link(item.title, item.url) }} 13 {% endif %} 14 {# … #} themes/flex_theme/templates/menu—main.html.twig Libraries can be attached from within a template files, by using the twig function ‘attach_library’. Attaching new library only when the template menu—main.html.twig is included on page.
The “JavaScript” menu item is altered a er custom JavaScript triggers, changing values and assigning a new class name for syling.
#6 HOOKS
THE ALTER DATA METHOD Provided by core and modules Requires PHP and Drupal skillset Requires custom theme or module
Can use Twig debug to learn naming convention for hooks
1 <!— THEME DEBUG —> 2 <!— THEME HOOK: ‘menu__main’ —> 3 <!— FILE NAME SUGGESTIONS: 4 X menu—main.html.twig 5 X menu—main.html.twig 6 * menu.html.twig 7 —> 8 <!— BEGIN OUTPUT from ‘themes/flex_theme/templates/menu—main.html.twig’ —> 9 <ul class=”clearfix menu”> 10 <!— // … —> 11 </ul> 12 <!— END OUTPUT from ‘themes/flex_theme/templates/menu—main.html.twig’ Twig debug information informs that theme hooks should contain ‘menu__main’ (line 2)
Will create a custom module (flex_module) to implement hooks.
1 // Implements hook_preprocess_HOOK(). 2 function flex_module_preprocess_menu__main(&$variables) { 3 // Loop through all menu tabs. 4 foreach ($variables[‘items’] as &$menu_tab) { 5 // Current tab pointing to node/6 ? 6 if ($menu_tab[‘url’]->toString() == ‘/node/6’) { 7 // Alter Title 8 $menu_tab[‘title’] .= ’ Alt’; 9 // Existing attributes? 10 $attributes = $menu_tab[‘url’]->getOption(‘attributes’); 11 // Add custom styling. 12 $attributes[‘style’] .= ‘color:#FFF;background:#F00;’; 13 // Add back modified attributes. 14 $menu_tab[‘url’]->setOption(‘attributes’, $attributes); 15 } 16 } 17 } module/custom/flex_module/flex_module.module Implement a preprocess hook targeted at the main menu. Loop through all the menu items and alter any that point to node/6
Can enable modules from command line using Drush.
“Hooks” menu item has been altered by using preprocess hook in a custom module
#7 SERVICES
THE REPLACE CORE METHOD Replace/Alter global systems Requires advanced Drupal and OOP skillset Requires a custom module
Using a custom service requires some PHP classes within a custom module.
1 namespace Drupal\flex_module; 2 3 use Drupal\Core\DependencyInjection\ServiceProviderBase; 4 use Drupal\Core\DependencyInjection\ContainerBuilder; 5 6 class FlexModuleServiceProvider extends ServiceProviderBase { 7 /** 8 * {@inheritdoc} 9 */ 10 public function alter(ContainerBuilder $container) { 11 // Override menu_link_tree class with custom. 12 $definition = $container->getDefinition(‘menu.link_tree’); 13 $definition->setClass(‘Drupal\flex_module\FlexModuleMenuLinkTree’); 14 } 15 } modules/custom/flex_module/src/FlexModuleServiceProvider.php Need to create a *ServiceProvider class that extends the ServiceProviderBase class (line 6). Will override the ‘alter’ method (lines 10 -14), and change the PHP class uses for the menu Tree service (lines 12 - 13)
1 namespace Drupal\flex_module; 2 use Drupal\Core\Menu\MenuLinkTree; 3 4 class FlexModuleMenuLinkTree extends MenuLinkTree { 5 // Overrides \Drupal\Core\Menu\MenuLinkTree::build(). 6 public function build(array $tree) { 7 $build = parent::build($tree); 8 if (isset($build[‘#items’]) && $build[‘#theme’] == ‘menu__main’) { 9 $n = 0; 10 foreach ($build[‘#items’] as &$item ) { 11 if (++$n == 8) { 12 // Change Title, path and add styling. 13 $item[‘title’] .= ’ Alt’; 14 $item[‘url’]->setOption(‘attributes’, array( 15 ‘style’ => ‘color:#00F;background:#FFA500;’, 16 )); 17 } 18 } 19 } 20 return $build; modules/custom/flex_module/src/FlexModuleMenuLinkTree.php 21 } Create a new service class that extends the core MenuLinkTree service (line 4). Will override the core ‘build’ method, so that can use custom logic to tartget the 8th main menu item.
Drupal now uses custom menu link tree service to render menu links. Custom logic thus casues the “Services” menu tab to be altered.
#8 COMBINATIONS
THE REAL WORLD METHOD Most control over Drupal Use multiple skillsets Requires more time and effort
1 namespace Drupal\flex_module; 2 use Drupal\Core\Menu\MenuLinkTree; 3 4 class FlexModuleMenuLinkTree extends MenuLinkTree { 5 // Overrides \Drupal\Core\Menu\MenuLinkTree::build(). 6 public function build(array $tree) { 7 $build = parent::build($tree); 8 if (isset($build[‘#items’]) && $build[‘#theme’] == ‘menu__main’) { 9 $n = 0; 10 foreach ($build[‘#items’] as &$item ) { 11 // … 12 if ($item[‘url’]->toString() == ‘/node/8’) { 13 $item[‘title’] .= ’ Alt’; 14 } 15 } 16 } 17 return $build; 18 } 19 } modules/custom/flex_module/src/FlexModuleMenuLinkTree.php Use custom service to alter the Display title of a menu link (lines 12 - 14)
1 // Implements hook_preprocess_HOOK(). 2 function flex_module_preprocess_menu__main(&$variables) { 3 $size = count($variables[‘items’]); 4 $m = 1; 5 // Loop through all menu tabs. 6 foreach ($variables[‘items’] as &$menu_tab) { 7 // Current tab pointing to node/6 ? 8 if ($menu_tab[‘url’]->toString() == ‘/node/6’) { 9 // … 10 } 11 $menu_tab[‘is_combo’] = ($m++ == $size); 12 } 13 } modules/custom/flex_module/flex_module.module Use a preprocess hook in a custom module to target items in main menu. Will add new menu item boolean attribute to check if last item (line #11).
1 (function ($, Drupal) { 2 “use strict”; 3 Drupal.behaviors.flexThemeMenuAlterMain = { 4 attach: function (context) { 5 $(‘.menu—main ul.menu li a’).each(function(){ 6 // … 7 if ($(this).data(‘combo’) == 1) { 8 $(this).addClass(‘combo-item’); 9 } 10 }); 11 } 12 } 13 })(jQuery, Drupal); themes/flex_theme/js/menu_alter_main.js Will use custom JavaScript that is part of a custom library to add the class ‘combo-item’ to any main menu link that has the data-attribute “combo”
1 .menu—main .menu li a.combo-item { 2 color: #000; 3 font-weight: 800; 4 text-shadow: 0 0 #000 !important; 5 background: red; /* not working, let’s see some red */ 6 background: -moz-linear-gradient( top , 7 rgba(255, 0, 0, 1) 0%, 8 rgba(255, 255, 0, 1) 15%, 9 rgba(0, 255, 0, 1) 30%, 10 rgba(0, 255, 255, 1) 50%, 11 rgba(0, 0, 255, 1) 65%, 12 rgba(255, 0, 255, 1) 80%, 13 rgba(255, 0, 0, 1) 100%); 14 background: -webkit-gradient(linear, left top, left bottom, 15 color-stop(0%, rgba(255, 0, 0, 1)), 16 color-stop(15%, rgba(255, 255, 0, 1)), 17 color-stop(30%, rgba(0, 255, 0, 1)), 18 color-stop(50%, rgba(0, 255, 255, 1)), 19 color-stop(65%, rgba(0, 0, 255, 1)), 20 color-stop(80%, rgba(255, 0, 255, 1)), themes/flex_theme/css/menu_alter.css 21 color-stop(100%, rgba(255, 0, 0, 1))); Write a CSS rule to change background color of any menu item with the class ‘combo-item’
1 <ul class=”menu”> 2 {% endif %} 3 {% for item in items %} 4 {# … #} 5 <li{{ item.attributes.addClass(classes) }}> 6 {% if item.title == ‘Twig’ %} 7 {# … #} 8 {% elseif item.is_combo %} 9 {{ link(item.title | reverse, item.url) }} 10 {% else %} 11 {{ link(item.title, item.url) }} 12 {% endif %} 13 {# … #} 14 </li> 15 {% endfor %} 16 </ul> theme/flex_theme/tempplates/menu—main.html.twig Will use a custom templte to build main menu. Will check to see if menu item has attribute ‘is_combo’ and if so, will reverse the menu text.
1 attributes: 2 class: 3 label: ” 4 description: ” 5 target: 6 label: ” 7 description: ” 8 options: 9 _blank: ‘New window (_blank)’ 10 _self: ‘Same window (_self)’ 11 style: 12 label: ” 13 description: ” 14 data-combo: 15 label: ‘Combo Item’ 16 description: ‘Is this a combo menu item?’ 17 options: 18 0: ‘No’ 19 1: ‘Yes’ 20 _core: 21 default_config_hash: 9nRDOclwSlz2Os9mJXM1LXNbV2q-bADV0zipiWPXymk Will update the configuration of Menu Link Attributes module, to include a custom ‘data-combo’ attribute (lines 14-19).
Will use Drupal core to edit menu item and set custom attribute ‘data-combo’ to ‘Yes’
Result of using multiple manipulations methods, the last menu item is greatly altered.
WHAT DID WE LEARN? Drupal is flexible! No “right” way, just “right for me” way
RESOURCES bit.ly/NYC16Flex This presentation bit.ly/NYC16FlexSlides Annotated Slides bit.ly/NYC16FlexCode Demo code (theme and module) mike-miles.com My blog
FEEDBACK @MIKEMILES86
THANK YOU!
No other CMS offers more flexibility then Drupal. If you need to implement a piece of functionality or change a piece of data, there are a million different ways you can go about it. However, this flexibility can also be daunting and frustrating.How do you know if you are going about your changes the “right” way? The truth of the matter is that there is no “right” way - just the “right for me” way. Any method you choose will come with it’s own sets of drawbacks and benefits.
In this session we will demonstrate the flexibility of Drupal by going over 8 different ways in Drupal 8 that data can be manipulated. From non-technical methods, “frontend” javascript & templating methods, to “Backend” methods such as building a custom module and overriding services. This session will demonstrate how to implement each one outlining their individual pros and cons, proving that no matter your skill sets you can make Drupal 8 do what you want.
