KeyFilter applied to FeatureFlags

[erik-neumann]

After upgrading to 8.1.0 we realized that some of our FeatureFlags do not properly load anymore. Those AppConfiguration instances that do not work anymore all have a KeyFilter (other than KeyFilter.Any) defined. Those with no filter or KeyFilter.Any are fine. Workaround seems to be adding .appconfig.featureflag/* to the KeyFilters.

    .UseFeatureFlags()
    .Select("Prefix:*")
    .Select(".appconfig.featureflag/*"); // We need to add this line to load feature flags properly

These configs are purely Azure AppConfiguration related, no conflicting appconfig.json or other provider setting does exist. I validated by checking the behaviour of config.Providers[].Data.

[zhiyuanliang-ms]

Hi, Erik Neumann (@erik-neumann) Sorry for the inconvenience. This is a bug. The reason of the bug is this line.

If you call UseFeatureFlags before calling Select, the feature flag selector (which is set here) will be cleared wrongly.

A better workaround would be calling Select before calling UseFeatureFlags

.Select("Prefix:*")
.UseFeatureFlags();

We will fix this bug as soon as possible.

[amerjusupovic]

Version 8.1.1 is now released with the fix for this issue