GitHub has enhanced its Issues search functionality by introducing support for nested queries and boolean operators, enabling users to construct complex searches using logical AND/OR operators and nested parentheses.
The development of this feature involved challenges such as maintaining backward compatibility, ensuring performance under high query volume, and creating a user-friendly experience for nested searches.
The new syntax allows users to build queries across all fields using logical operators, for example, finding all issues that are open, authored by a specific user, and of certain types.
Previously, Issues search only supported a flat list of query fields and terms joined by a logical AND. The community's demand for more flexibility in search led to the implementation of advanced search capabilities.
The technical architecture involved swapping out the existing search module with a new module capable of handling nested queries while supporting the existing query formats.
The development process included stages like parsing the user input, transforming it into an Elasticsearch query document, and executing the query against Elasticsearch.
To ensure backward compatibility, extensive testing was conducted, and a validation process was implemented, comparing results from the old and new search systems.
Preventing performance degradation was a key consideration, with strategies like running equivalent queries against both systems and carefully refactoring critical paths using scientist, a Ruby library.
User experience was preserved by limiting the number of nested query levels, providing helpful UI cues, and collaborating with product and design teams.
The rollout of the new feature was done cautiously to minimize risk to users, with a phased integration approach and internal testing before wider release.