Top 10 Drupal Interview Questions and Answers 2024

Custom modules and themes can be created in Drupal using PHP and CSS/HTML respectively.

• To create a custom module, define a .info.yml file, a .module file, and a .routing.yml file.

• To create a custom theme, define a .info.yml file, a .theme file, and a .libraries.yml file.

• Use Drupal's hook system to add functionality to your module.

• Use Twig templates to customize the HTML/CSS of your theme.

• Use Drupal's theming functions to add dynamic content to your theme.

• Examples of custom mo...read more

Debugging in Drupal involves using tools like Devel module, watchdog(), and error logs.

• Enable Devel module for debugging information

• Use watchdog() function to log messages to Drupal's watchdog log

• Check error logs for PHP errors and warnings

• Use dpm() function to print variables for debugging purposes

To add Drupal patches, use the patch command in the terminal.

• Download the patch file and place it in the root directory of the Drupal installation.

• Open the terminal and navigate to the root directory of the Drupal installation.

• Run the command 'patch -p1 < [patch_file_name].patch' to apply the patch.

• Verify that the patch has been applied successfully by checking the affected files.

Drupal provides various services to extend its functionality and features.

• Drupal core services such as database, cache, and logging

• Third-party services like RESTful web services, search, and email

• Custom services created by developers to meet specific needs

• Services can be accessed through Drupal's Service Container

Types of Drupal entities include nodes, users, taxonomy terms, and custom entities.

• Nodes: Basic content type in Drupal, can represent articles, pages, etc.

• Users: Represents individuals who can log in and interact with the site.

• Taxonomy terms: Used for categorizing content.

• Custom entities: Entities created by developers for specific needs.

Developed a custom Drupal module for creating a custom content type with specific fields and functionality.

• Created a custom module folder within the Drupal installation

• Defined the custom content type and its fields in the module's .info file

• Implemented hook functions to handle data processing and display logic

• Used Drupal's Form API to create custom forms for data input and editing

• Integrated with other Drupal modules or external services for additional functionality

Drupal Cache Mechanism stores and retrieves data to improve website performance.

• Drupal has multiple cache bins like page cache, block cache, and dynamic page cache.

• Cache tags are used to invalidate specific cache items when content is updated.

• Cache contexts allow different versions of a page to be served based on user roles or languages.

• Cache max-age sets the time for which a cached item is considered valid before it needs to be refreshed.

Drupal best practices involve following coding standards, using modules wisely, optimizing performance, and maintaining security.

• Follow Drupal coding standards to ensure consistency and readability of code

• Use contributed modules from trusted sources and avoid unnecessary custom code

• Optimize performance by caching content, enabling compression, and minimizing database queries

• Maintain security by keeping Drupal core and modules up to date, using secure coding practices, and imp...read more

Drupal 7 and 9 have significant differences in terms of technology, features, and performance.

• Drupal 9 has removed deprecated code from Drupal 7 and introduced new features like the Layout Builder and Claro admin theme.

• Drupal 9 requires PHP 7.3 or higher, while Drupal 7 supports PHP 5.6.

• Drupal 9 has improved performance and security compared to Drupal 7.

• Drupal 9 has better support for modern web technologies like HTML5 and CSS3.

• Drupal 9 has a more streamlined upgrade process ...read more

To create a custom form in Drupal, you can use the Form API to define the form structure and functionality.

• Use hook_form_alter() to modify existing forms or hook_form_FORM_ID_alter() to alter a specific form.

• Define the form elements using the Form API functions like 'textfield', 'select', 'submit', etc.

• Implement a submit handler to process the form data and perform any necessary actions.

• Use the Form API validation functions to validate user input before submission.

Drupal 8 offers improved performance, better security, and more modern features compared to Drupal 7.

• Drupal 8 has a more user-friendly admin interface

• Drupal 8 uses Symfony components for improved performance

• Drupal 8 has better multilingual support out of the box

• Drupal 8 has improved content authoring capabilities with CKEditor integration

• Drupal 8 has enhanced mobile responsiveness with built-in responsive themes

Creating a custom theme in Drupal involves creating a new folder in the themes directory and adding necessary files.

• Create a new folder in the themes directory with a unique name

• Add a .info.yml file to define the theme

• Create a .theme file for theme-specific functions

• Add CSS and JS files for styling and functionality

• Enable the custom theme in the Drupal admin interface

Drupal views allow for filtering and aggregating content based on context filters.

• Context filters allow you to filter content based on contextual information, such as the current user or page being viewed.

• Aggregation allows you to group and summarize content based on certain criteria, such as counting the number of items in a category.

• Combining context filters and aggregation can provide powerful ways to display and analyze content in Drupal views.