Make React Native device-ID promises settle before trusting telemetry startup

Source facts

The React Native plug-in’s device-information interface permits getUniqueId to return a string or a promise. For a promise, event processing waits until it resolves or rejects. Microsoft documents a default five-second uniqueIdPromiseTimeout that unblocks processing using a previously configured value, and setDeviceId can also release the waiting state. The source warns against an implementation whose promise never settles. Microsoft Learn.

Applicability

Investigate this startup dependency when the application supplies its own device-information module. Keep the identity lookup’s completion and the later delivery of telemetry as separate observations; neither an initialized SDK nor an eventual event proves the custom lookup behaved correctly.

DSE recommendation

Define explicit success and failure completion for the custom device-ID lookup and test both paths during application startup. Ask the developer to document the intended fallback rather than relying on an accidental timeout. Avoid changing the identity scheme merely to conceal a blocked startup dependency, and keep any chosen identifier consistent with the application’s approved data-handling design.

Verification

In a test build, exercise immediate success, deliberate rejection and a lookup delayed beyond the configured timeout. Record when the lookup settles, when event processing resumes and which expected identifier is attached. Confirm that the fallback behavior is intentional and does not misattribute events. Keep a never-settling implementation as a defect even if the documented timeout eventually allows telemetry to continue.

Official references

Microsoft Learn: JavaScript framework extensions and device information. Source reviewed September 9, 2026.