[PM-3708] Allow local overrides for flag values (#3243)

* Allow local overrides for flag values

* Rename helper method

src/Core/Constants.cs

@@ -46,4 +46,13 @@ public static class FeatureFlagKeys
             .Select(x => (string)x.GetRawConstantValue())
             .ToList();
     }
+
+    public static Dictionary<string, string> GetLocalOverrideFlagValues()
+    {
+        // place overriding values when needed locally (offline), or return null
+        return new Dictionary<string, string>()
+        {
+            { TrustedDeviceEncryption, "true" }
+        };
+    }
 }

src/Core/Services/Implementations/LaunchDarklyFeatureService.cs

@@ -29,24 +29,12 @@ public class LaunchDarklyFeatureService : IFeatureService, IDisposable
             // support configuration directly from settings
             else if (globalSettings.LaunchDarkly?.FlagValues?.Any() is true)
             {
-                var source = TestData.DataSource();
-                foreach (var kvp in globalSettings.LaunchDarkly.FlagValues)
-                {
-                    if (bool.TryParse(kvp.Value, out bool boolValue))
-                    {
-                        source.Update(source.Flag(kvp.Key).ValueForAll(LaunchDarkly.Sdk.LdValue.Of(boolValue)));
-                    }
-                    else if (int.TryParse(kvp.Value, out int intValue))
-                    {
-                        source.Update(source.Flag(kvp.Key).ValueForAll(LaunchDarkly.Sdk.LdValue.Of(intValue)));
-                    }
-                    else
-                    {
-                        source.Update(source.Flag(kvp.Key).ValueForAll(LaunchDarkly.Sdk.LdValue.Of(kvp.Value)));
-                    }
-                }
-
-                ldConfig.DataSource(source);
+                ldConfig.DataSource(BuildDataSource(globalSettings.LaunchDarkly.FlagValues));
+            }
+            // support local overrides
+            else if (FeatureFlagKeys.GetLocalOverrideFlagValues()?.Any() is true)
+            {
+                ldConfig.DataSource(BuildDataSource(FeatureFlagKeys.GetLocalOverrideFlagValues()));
             }
             else
             {
@@ -187,4 +175,26 @@ public class LaunchDarklyFeatureService : IFeatureService, IDisposable
 
         return builder.Build();
     }
+
+    private TestData BuildDataSource(Dictionary<string, string> values)
+    {
+        var source = TestData.DataSource();
+        foreach (var kvp in values)
+        {
+            if (bool.TryParse(kvp.Value, out bool boolValue))
+            {
+                source.Update(source.Flag(kvp.Key).ValueForAll(LaunchDarkly.Sdk.LdValue.Of(boolValue)));
+            }
+            else if (int.TryParse(kvp.Value, out int intValue))
+            {
+                source.Update(source.Flag(kvp.Key).ValueForAll(LaunchDarkly.Sdk.LdValue.Of(intValue)));
+            }
+            else
+            {
+                source.Update(source.Flag(kvp.Key).ValueForAll(LaunchDarkly.Sdk.LdValue.Of(kvp.Value)));
+            }
+        }
+
+        return source;
+    }
 }

test/Core.Test/Services/LaunchDarklyFeatureServiceTests.cs

@@ -20,14 +20,6 @@ public class LaunchDarklyFeatureServiceTests
             .Create();
     }
 
-    [Fact]
-    public void Offline_WhenSelfHost()
-    {
-        var sutProvider = GetSutProvider(new Core.Settings.GlobalSettings() { SelfHosted = true });
-
-        Assert.False(sutProvider.Sut.IsOnline());
-    }
-
     [Theory, BitAutoData]
     public void DefaultFeatureValue_WhenSelfHost(string key)
     {