Upcoming changes to schema composition for Schema Stitching projects

Laurin Quast

Due to limitations within the stitching implementation powered by graphql-tools (opens in a new tab), we are going to slightly alter the behaviour of the schema composition for better predictability of the schema composition result.

Currently, composition for schema stitching projects can lead to unexpected (seemingly unpredictable schema changes) appearing when publishing a service schema or running a schema check.

The reason for this is that the composite schema output from the stitching composition implementation is affected by the order of the input (subgraph) schemas. Today, the input schemas/subgraphs for the composition are ordered by their creation date (publish date). This means that each publish/check (unless they are strictly run in the same order), can result in a different output schema.

Some of you reached out to us because of this confusion and unpredictability.

Due to these limitations, we decided to make subtle changes to the sorting of the input subgraph schemas in order to make the output composite schema more predictable.

Starting on 20.04.2024, the subgraphs will always be sorted alphanumerically by their name to ensure a stable input order across schema publishes and schema checks.

We also recommend everyone that uses the graphql-tools stitching implementation to sort their schemas alphanumerically by their name in their gateway implementation. The Hive CDN will also serve the service list in that given order.