private void GetEnvironmentVariablesForFeature(NuGetFeatureFlagConstants featureFlag, out bool isFeatureForcedEnabled, out bool isFeatureForcedDisabled)
{
isFeatureForcedEnabled = false;
isFeatureForcedDisabled = false;
if (!string.IsNullOrEmpty(featureFlag.EnvironmentVariable))
{
string envVarOverride = _environmentVariableReader.GetEnvironmentVariable(featureFlag.EnvironmentVariable);
isFeatureForcedDisabled = envVarOverride == "0";
isFeatureForcedEnabled = envVarOverride == "1";
}
}
public async Task <bool> IsFeatureEnabledAsync(NuGetFeatureFlagConstants featureFlag)
{
GetEnvironmentVariablesForFeature(featureFlag, out bool isFeatureForcedEnabled, out bool isFeatureForcedDisabled);
// Perform the check from the feature flag service only once.
// There are events sent for targetted notification changes, but we don't listen to those at this point.
if (!_featureFlagCache.TryGetValue(featureFlag.Name, out bool featureEnabled))
{
var featureFlagService = await _ivsFeatureFlags.GetValueAsync();
await NuGetUIThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync();
featureEnabled = featureFlagService.IsFeatureEnabled(featureFlag.Name, defaultValue: featureFlag.DefaultState);
_featureFlagCache.Add(featureFlag.Name, featureEnabled);
}
return(!isFeatureForcedDisabled && (isFeatureForcedEnabled || featureEnabled));
}