Drupal 7 to 9 Migration for Enterprise Content Management

Introduction: Large enterprise with an extensive online presence, faced the challenge of upgrading its Drupal 7-based content management system to the latest version, Drupal 9. This case study delves into the migration process, focusing on the challenges encountered and the strategies employed to overcome them.

Challenges Faced:

  1. Deprecated Modules:
    • The existing Drupal 7 installation relied on several contributed modules that were deprecated or no longer supported in Drupal 9.
    • The migration team had to identify suitable replacements and assess the impact on existing functionality.
    • Custom modules interacting with deprecated ones posed additional challenges and required thorough code review and refactoring.
  2. Theme Updates:
    • The Drupal 7 theme was incompatible with the newer theming system introduced in Drupal 8 and continued in Drupal 9.
    • The design had to be modernized to adhere to Drupal's new theming standards.
    • Legacy CSS and JavaScript needed adjustment to align with the latest best practices and to ensure a responsive user experience across devices.
  3. Database Migration:
    • The database schema in Drupal 9 differed significantly from Drupal 7.
    • Data mapping and transformation were critical, especially for content types, fields, and configurations.
    • Legacy data inconsistencies and redundancies needed resolution to maintain data integrity in the upgraded system.

Strategies and Solutions:

  1. Module Replacement and Customization:
    • The migration team conducted a thorough analysis of contributed modules in use.
    • Deprecated modules were replaced with Drupal 9 equivalents or custom solutions were developed where necessary.
    • An iterative approach was adopted, addressing each module's migration individually to minimize disruptions.
  2. Theming Overhaul:
    • The theme was redesigned following Drupal 9 theming standards, incorporating responsive design principles.
    • CSS and JavaScript were refactored to leverage Drupal 9's asset management system.
    • User acceptance testing played a crucial role in ensuring the new theme met both functional and aesthetic requirements.
  3. Database Migration and Data Cleansing:
    • A meticulous mapping process was undertaken to migrate content types, taxonomies, and other data entities.
    • Legacy data inconsistencies were addressed during the migration process, preventing the carryover of issues to the upgraded system.
    • Regular backups and version control were used to mitigate risks and facilitate rollback in case of unforeseen issues.

Outcome: The successful migration resulted in an up-to-date Drupal 9 content management system for Corporation. The website now benefits from improved security, performance, and the latest features offered by the Drupal community. Despite the challenges, the project was completed within the stipulated timeframe, showcasing the resilience and expertise of the migration team.

Conclusion: This case study illustrates the complexity of migrating from Drupal 7 to Drupal 9, emphasizing the importance of a well-planned strategy, thorough testing, and collaboration between development and content teams. It highlights the adaptability and robustness of Drupal's migration tools and the commitment of the development team to overcome obstacles and deliver a successful migration.