https://github.com/serilog/serilog-settings-configuration/issues/10

Author: Sergey Komisarchik

sample/Sample/appsettings.json

@@ -1,7 +1,13 @@
 {
   "Serilog": {
     "Using":  ["Serilog.Sinks.Literate"],
-    "MinimumLevel": "Debug",
+    "MinimumLevel": {
+      "Default": "Debug",
+      "Override": {
+        "Microsoft": "Warning",
+        "MyApp.Something.Tricky": "Verbose"
+      }
+    },
     "WriteTo": [
       { "Name": "LiterateConsole" },
       {        

src/Serilog.Settings.Configuration/Settings/Configuration/ConfigurationReader.cs

@@ -100,25 +100,39 @@ Dictionary<string, Dictionary<string, string>> GetMethodCalls(IConfigurationSect
 
         void ApplyMinimumLevel(LoggerConfiguration loggerConfiguration)
         {
+            var applyMinimumLevelAction =
+                new Action<IConfigurationSection, Action<LoggerMinimumLevelConfiguration, LoggingLevelSwitch>>(
+                    (directive, applyConfigAction) =>
+                    {
+                        LogEventLevel minimumLevel;
+                        if (!Enum.TryParse(directive.Value, out minimumLevel))
+                            throw new InvalidOperationException($"The value {directive.Value} is not a valid Serilog level.");
+
+                        var levelSwitch = new LoggingLevelSwitch(minimumLevel);
+                        applyConfigAction(loggerConfiguration.MinimumLevel, levelSwitch);
+
+                        ChangeToken.OnChange(
+                            directive.GetReloadToken,
+                            () =>
+                            {
+                                if (Enum.TryParse(directive.Value, out minimumLevel))
+                                    levelSwitch.MinimumLevel = minimumLevel;
+                                else
+                                    SelfLog.WriteLine($"The value {directive.Value} is not a valid Serilog level.");
+                            });
+                    });
+
             var minimumLevelDirective = _configuration.GetSection("MinimumLevel");
-            if (minimumLevelDirective?.Value != null)
-            {
-                LogEventLevel minimumLevel;
-                if (!Enum.TryParse(minimumLevelDirective.Value, out minimumLevel))
-                    throw new InvalidOperationException($"The value {minimumLevelDirective.Value} is not a valid Serilog level.");
 
-                var levelSwitch = new LoggingLevelSwitch(minimumLevel);
-                loggerConfiguration.MinimumLevel.ControlledBy(levelSwitch);
+            var defaultMinLevelDirective = minimumLevelDirective.Value != null ? minimumLevelDirective : minimumLevelDirective.GetSection("Default");
+            if (defaultMinLevelDirective.Value != null)
+            {
+                applyMinimumLevelAction(defaultMinLevelDirective, (configuration, levelSwitch) => configuration.ControlledBy(levelSwitch));
+            }
 
-                ChangeToken.OnChange(
-                    () => minimumLevelDirective.GetReloadToken(),
-                    () =>
-                    {
-                        if (Enum.TryParse(minimumLevelDirective.Value, out minimumLevel))
-                            levelSwitch.MinimumLevel = minimumLevel;
-                        else
-                            SelfLog.WriteLine($"The value {minimumLevelDirective.Value} is not a valid Serilog level.");
-                    });
+            foreach (var overrideDirective in minimumLevelDirective.GetSection("Override").GetChildren())
+            {
+                applyMinimumLevelAction(overrideDirective, (configuration, levelSwitch) => configuration.Override(overrideDirective.Key, levelSwitch));
             }
         }