Summary

From 2022-08-05 12:02 PM PT to 2:22 PM, update manifests served from EAS Update would cause apps that received a new update not to launch.

Scope

Apps that received a new update during this time frame would not launch.

If an app was already launched and backgrounded, it was not affected. If an app checked for an update and already had the latest update or had no update available, it was not affected.

Cause

The Expo Updates specification defines a way to specify the HTTP headers a client should use when requesting assets. The expo-updates module supported parsing string-valued headers but not other types. During this incident, the EAS Update service declared a Boolean-valued header, which caused a parsing error.

Resolution

Resiliency: the next release of the expo-updates library will handle non-string-valued headers by converting them to strings. Longer-term, we are thinking about ways to handle broader classes of errors.

Test coverage: we added an end-to-end test running an Android app with EAS Update’s staging tier.

Documentation: the Expo Updates specification now mentions that header values must be strings.