Supporting alignment across GA4GH standards: TASC seeks feedback on new pagination guide

21 Feb 2024

The Technical Alignment Subcommittee (TASC) aims to harmonise aspects of GA4GH technical products and support interoperability. Learn more and provide feedback on their current project about pagination methods.

The GA4GH Technical Alignment Subcommittee (TASC) has developed recommendations for how GA4GH technical products handle pagination. The community is invited to provide feedback and attend an open meeting on February 26 at 14:00 UTC.

When an investigator queries a database, they may receive hundreds or even thousands of results back. To help the user process and navigate the information, software applications use a technique called pagination. In their latest project, TASC provides guidelines for how software developers can implement pagination in GA4GH products.

TASC launched in 2020 to ensure GA4GH standards can be used together effectively, collecting issues from across the Work Streams and developing guidance to support technical consistency and alignment. Members of TASC, which include at least one representative from each Work Stream, bring together knowledge and expertise from multiple organisations and countries. Through its efforts, TASC aims to lower the barriers to GA4GH-wide interoperability and, in turn, increase adoption of GA4GH standards: a key imperative of the 2020 GA4GH Strategic Plan. 

Getting on the same page about pagination 

There are a variety of pagination methods used in software development, and developers across GA4GH will at some point decide how to implement it. To support alignment across the Work Streams and improve both the developer and user experience, TASC aims to simplify the decision making process and share guidance with the community.

Pagination involves dividing data into smaller, more manageable chunks instead of receiving one long response back from a data query.  Like turning the pages of a book, which makes it easier for the reader to keep their place, pagination provides a structured approach to navigating information — making it easier to process, display, and analyse data. Behind the scenes, pagination also improves computer performance, like improving efficiency when executing a task or reducing the size of result payloads.

After reviewing and describing pagination methods used by the Tool Registry Service, Beacon, and Data Connect APIs, TASC proposes that GA4GH technical products use either offset-based or token-based pagination methods. 

For use cases in which users wish to explore and jump around within a small result set, TASC recommends employing offset based pagination. This flexible approach allows the user to skip pages at will and configure the number of records they would like to see at a time. To implement offset-based pagination, TASC suggests encoding two parameters — the maximum number of records to display, and from which “page” to retrieve that data.

When implementing pagination on a much larger result set, TASC recommends switching over to token-based pagination. In token-based pagination, the user feeds a unique token to the application, which then returns a specified page of data. The application also responds back with a token for the next page of data, ensuring consistency and predictability. 

In the current draft of the pagination guide, TASC encourages new GA4GH standards to apply one of these two techniques depending on their use case, and invites existing GA4GH standards to consult with TASC on whether and how to adopt these approaches. 

To share your thoughts on the pagination guide, TASC invites the community to attend the next TASC meeting on February 26 at 14:00 UTC. Feedback can also be submitted through the Github issues page in the TASC repository.