5.7.0

[5.7.0] - 2022-01-07

Added:

• HTTPConfigurationBuilder.Header allows adding custom HTTP headers to all of the SDK's requests.

Changed:

• The SDK will now log a message at Error level whenever it detects flag data that should not be possible according to LaunchDarkly's validation rules (for instance, a rule that references a nonexistent variation index, or a circular reference in flag prerequisites). Previously, such messages were only logged at Warn level and only if LoggingConfigurationBuilder.LogEvaluationErrors was enabled; that is still the default behavior for other kinds of errors (such as "flag not found"), but malformed data is considered a more serious error because it should not be possible and may require assistance from LaunchDarkly support.

Fixed:

• If the SDK detects a circular reference in flag prerequisites (for example, flag A has flag B as a prerequisite and vice versa), it will now refuse to evaluate the affected flags, returning the default value and an error reason of MALFORMED_FLAG. Previously, such a condition would cause infinite recursion and a stack overflow. LaunchDarkly does not allow circular references to be created in flag configurations, but under rare circumstances an SDK could incorrectly perceive such a state if it received updates out of order; or, the SDK could be configured to use data from a file that contained such references.