make '$' sign optional for minimum level / filter switch declarations

CHANGES.md

@@ -2,12 +2,14 @@
 
 3.2.0 (pre-release)
 
+* #162 - LoggingFilterSwitch support
 * #202 - added support to AuditTo.Logger
 * #203 - added support for custom types in arrays and custom collections
 * #218 - fixed an issue with `dotnet restore` with `rid` specified if referenced from `netstandard` project
 * #219 - reduced search graph for configuration dlls to avoid native assets
 * #221 - added support for conditional/leveled enrichers from Serilog 2.9+
 * #222 - updated Microsoft.Extensions.DependencyModel
+* #231 - make '$' sign optional for minimum level / filter switch declarations
 * #237 - DependencyContextAssemblyFinder fix: check `serilog` at the start of the name for any dependent package
 * #239 - handle NotSupportedException for .net 5.0 single file applications
 

Directory.Build.props

@@ -1,6 +1,8 @@
 <Project>
   <PropertyGroup>
     <LangVersion>latest</LangVersion>
+    <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
+    <TreatSpecificWarningsAsErrors />
   </PropertyGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'">

README.md

@@ -140,12 +140,12 @@ Any changes for `Default`, `Microsoft`, `System` sources will be applied at runt
 
 (Note: only existing sources are respected for a dynamic update. Inserting new records in `Override` section is **not** supported.)
 
-You can also declare `LoggingLevelSwitch`-es in custom section and reference them for Sink parameters:
+You can also declare `LoggingLevelSwitch`-es in custom section and reference them for sink parameters:
 
 ```json
 {
     "Serilog": {
-        "LevelSwitches": { "$controlSwitch": "Verbose" },
+        "LevelSwitches": { "controlSwitch": "Verbose" },
         "WriteTo": [
             {
                 "Name": "Seq",
@@ -205,7 +205,7 @@ This section defines a static list of key-value pairs that will enrich log event
 
 ### Filter section
 
-This section defines filters that will be applied to log events. It is especially usefull in combination with _[Serilog.Filters.Expression](https://github.com/serilog/serilog-filters-expressions)_ package so you can write expression in text form:
+This section defines filters that will be applied to log events. It is especially usefull in combination with _[Serilog.Filters.Expression](https://github.com/serilog/serilog-expressions)_ (or legacy _[Serilog.Filters.Expression](https://github.com/serilog/serilog-filters-expressions)_) package so you can write expression in text form:
 
 ```json
 "Filter": [{
@@ -216,6 +216,25 @@ This section defines filters that will be applied to log events. It is especiall
 }]
 ```
 
+Using this package you can also declare `LoggingFilterSwitch`-es in custom section and reference them for filter parameters:
+
+```json
+{
+    "Serilog": {
+        "FilterSwitches": { "filterSwitch": "Application = 'Sample'" },
+        "Filter": [
+            {
+                "Name": "ControlledBy",
+                "Args": {
+                    "switch": "$filterSwitch"
+                }
+            }
+        ]
+}
+```
+
+Level updates to switches are also respected for a dynamic update.
+
 ### Nested configuration sections
 
 Some Serilog packages require a reference to a logger configuration object. The sample program in this project illustrates this with the following entry configuring the _[Serilog.Sinks.Async](https://github.com/serilog/serilog-sinks-async)_ package to wrap the _[Serilog.Sinks.File](https://github.com/serilog/serilog-sinks-file)_ package. The `configure` parameter references the File sink configuration:

sample/Sample/Program.cs

@@ -10,7 +10,6 @@
 using Serilog;
 using Serilog.Core;
 using Serilog.Events;
-using System.Collections.Generic;
 using Serilog.Debugging;
 
 namespace Sample
@@ -19,6 +18,8 @@ public class Program
     {
         public static void Main(string[] args)
         {
+            SelfLog.Enable(Console.Error);
+
             Thread.CurrentThread.Name = "Main thread";
 
             var configuration = new ConfigurationBuilder()

sample/Sample/appsettings.json

@@ -1,7 +1,7 @@
 {
   "Serilog": {
     "Using": [ "Serilog.Sinks.Console" ],
-    "LevelSwitches": { "$controlSwitch": "Verbose" },
+    "LevelSwitches": { "controlSwitch": "Verbose" },
     "FilterSwitches": { "$filterSwitch": "Application = 'Sample'" },
     "MinimumLevel": {
       "Default": "Debug",

src/Serilog.Settings.Configuration/Serilog.Settings.Configuration.csproj

@@ -31,7 +31,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0" PrivateAssets="All"/>
     <PackageReference Include="Microsoft.Extensions.DependencyModel" Version="3.0.0" />
-    <PackageReference Include="Serilog" Version="2.9.0" />
+    <PackageReference Include="Serilog" Version="2.10.0" />
     <None Include="..\..\assets\icon.png" Pack="true" PackagePath=""/>
   </ItemGroup>
 

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

@@ -3,9 +3,10 @@
 using System.Linq;
 using System.Reflection;
 using System.Runtime.CompilerServices;
+using System.Text.RegularExpressions;
+
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Primitives;
-using System.Text.RegularExpressions;
 
 using Serilog.Configuration;
 using Serilog.Core;
@@ -17,7 +18,7 @@ namespace Serilog.Settings.Configuration
 {
     class ConfigurationReader : IConfigurationReader
     {
-        const string LevelSwitchNameRegex = @"^\$[A-Za-z]+[A-Za-z0-9]*$";
+        const string LevelSwitchNameRegex = @"^\${0,1}[A-Za-z]+[A-Za-z0-9]*$";
 
         readonly IConfigurationSection _section;
         readonly IReadOnlyCollection<Assembly> _configurationAssemblies;
@@ -68,7 +69,7 @@ void ProcessFilterSwitchDeclarations()
                 // switchName must be something like $switch to avoid ambiguities
                 if (!IsValidSwitchName(switchName))
                 {
-                    throw new FormatException($"\"{switchName}\" is not a valid name for a Filter Switch declaration. Filter switch must be declared with a '$' sign, like \"FilterSwitches\" : {{\"$switchName\" : \"{{FilterExpression}}\"}}");
+                    throw new FormatException($"\"{switchName}\" is not a valid name for a Filter Switch declaration. The first character of the name must be a letter or '$' sign, like \"FilterSwitches\" : {{\"$switchName\" : \"{{FilterExpression}}\"}}");
                 }
 
                 SetFilterSwitch(throwOnError: true);
@@ -118,7 +119,7 @@ void ProcessLevelSwitchDeclarations()
                 // switchName must be something like $switch to avoid ambiguities
                 if (!IsValidSwitchName(switchName))
                 {
-                    throw new FormatException($"\"{switchName}\" is not a valid name for a Level Switch declaration. Level switch must be declared with a '$' sign, like \"LevelSwitches\" : {{\"$switchName\" : \"InitialLevel\"}}");
+                    throw new FormatException($"\"{switchName}\" is not a valid name for a Level Switch declaration. The first character of the name must be a letter or '$' sign, like \"LevelSwitches\" : {{\"$switchName\" : \"InitialLevel\"}}");
                 }
 
                 LoggingLevelSwitch newSwitch;

src/Serilog.Settings.Configuration/Settings/Configuration/ResolutionContext.cs

@@ -67,14 +67,19 @@ public void AddLevelSwitch(string levelSwitchName, LoggingLevelSwitch levelSwitc
         {
             if (levelSwitchName == null) throw new ArgumentNullException(nameof(levelSwitchName));
             if (levelSwitch == null) throw new ArgumentNullException(nameof(levelSwitch));
-            _declaredLevelSwitches[levelSwitchName] = levelSwitch;
+            _declaredLevelSwitches[ToSwitchReference(levelSwitchName)] = levelSwitch;
         }
 
         public void AddFilterSwitch(string filterSwitchName, LoggingFilterSwitchProxy filterSwitch)
         {
             if (filterSwitchName == null) throw new ArgumentNullException(nameof(filterSwitchName));
             if (filterSwitch == null) throw new ArgumentNullException(nameof(filterSwitch));
-            _declaredFilterSwitches[filterSwitchName] = filterSwitch;
+            _declaredFilterSwitches[ToSwitchReference(filterSwitchName)] = filterSwitch;
+        }
+
+        string ToSwitchReference(string switchName)
+        {
+            return switchName.StartsWith("$") ? switchName : $"${switchName}";
         }
     }
 }

test/Serilog.Settings.Configuration.Tests/ConfigurationSettingsTests.cs

@@ -305,8 +305,10 @@ public void SinksAreConfiguredWithStaticMember()
         [Theory]
         [InlineData("$switchName", true)]
         [InlineData("$SwitchName", true)]
+        [InlineData("SwitchName", true)]
         [InlineData("$switch1", true)]
         [InlineData("$sw1tch0", true)]
+        [InlineData("sw1tch0", true)]
         [InlineData("$SWITCHNAME", true)]
         [InlineData("$$switchname", false)]
         [InlineData("$switchname$", false)]
@@ -326,32 +328,34 @@ public void LoggingLevelSwitchNameValidityScenarios(string switchName, bool expe
         public void LoggingLevelSwitchWithInvalidNameThrowsFormatException()
         {
             var json = @"{
-                ""Serilog"": {            
-                    ""LevelSwitches"": {""switchNameNotStartingWithDollar"" : ""Warning"" }
+                ""Serilog"": {
+                    ""LevelSwitches"": {""1InvalidSwitchName"" : ""Warning"" }
                 }
             }";
 
             var ex = Assert.Throws<FormatException>(() => ConfigFromJson(json));
 
-            Assert.Contains("\"switchNameNotStartingWithDollar\"", ex.Message);
+            Assert.Contains("\"1InvalidSwitchName\"", ex.Message);
             Assert.Contains("'$' sign", ex.Message);
             Assert.Contains("\"LevelSwitches\" : {\"$switchName\" :", ex.Message);
         }
 
-        [Fact]
-        public void LoggingFilterSwitchIsConfigured()
+        [Theory]
+        [InlineData("$mySwitch")]
+        [InlineData("mySwitch")]
+        public void LoggingFilterSwitchIsConfigured(string switchName)
         {
-            var json = @"{
-                'Serilog': {
-                    'FilterSwitches': { '$mySwitch': 'Prop = 42' },
-                    'Filter:BySwitch': {
+            var json = $@"{{
+                'Serilog': {{
+                    'FilterSwitches': {{ '{switchName}': 'Prop = 42' }},
+                    'Filter:BySwitch': {{
                         'Name': 'ControlledBy',
-                        'Args': {
+                        'Args': {{
                             'switch': '$mySwitch'
-                        }
-                    }
-                }
-            }";
+                        }}
+                    }}
+                }}
+            }}";
             LogEvent evt = null;
 
             var log = ConfigFromJson(json)
@@ -365,17 +369,19 @@ public void LoggingFilterSwitchIsConfigured()
             Assert.NotNull(evt);
         }
 
-        [Fact]
-        public void LoggingLevelSwitchIsConfigured()
+        [Theory]
+        [InlineData("$switch1")]
+        [InlineData("switch1")]
+        public void LoggingLevelSwitchIsConfigured(string switchName)
         {
-            var json = @"{
-                ""Serilog"": {            
-                    ""LevelSwitches"": {""$switch1"" : ""Warning"" },
-                    ""MinimumLevel"" : {
-                        ""ControlledBy"" : ""$switch1""
-                    }
-                }
-            }";
+            var json = $@"{{
+                'Serilog': {{
+                    'LevelSwitches': {{ '{switchName}' : 'Warning' }},
+                    'MinimumLevel' : {{
+                        'ControlledBy' : '$switch1'
+                    }}
+                }}
+            }}";
             LogEvent evt = null;
 
             var log = ConfigFromJson(json)