About the feature

Content management systems, especially those with a large amount of content, practically require that content to be searchable. Search engines such as Google have made search features ubiquitous, as users expect to find what they want and need as quickly as possible. Drupal is built to manage content and is capable of managing content at scale. As such, the search function is a widely used and popular feature that is built into the Drupal core and is highly extensible. Next, we explore how search capabilities are built into Drupal.

Implementation

The search function is a specific feature built on top of existing content entities. Other systems introduce their entity types, but the functionality provided by the search function is only designed for the existing content-related entity types. This feature is provided by the Search module in Drupal core.

Implementing a search function requires an index for storage. At a high level, this can be considered a mapping...