docs(dotnet/logs): add log4net structured logs integration

docs/platforms/dotnet/common/logs/index.mdx

@@ -6,7 +6,6 @@ sidebar_order: 2
 sidebar_section: features
 notSupported:
   - dotnet.google-cloud-functions
-  - dotnet.log4net
   - dotnet.nlog
   - dotnet.xamarin
 ---

docs/platforms/dotnet/guides/log4net/index.mdx

@@ -9,6 +9,8 @@ Sentry provides an integration with log4net through the [Sentry.Log4Net NuGet pa
 
 Without any code change, this package is able to initialize the Sentry SDK and capture events while including additional properties like `Exception` data and more.
 
+Additionally, when enabled, log messages are sent to Sentry as [Structured Logs](logs/).
+
 ## Install
 
 Add the Sentry dependency:

docs/product/logs/getting-started/index.mdx

@@ -332,6 +332,12 @@ To set up Sentry Logs, use the links below for supported SDKs. After it's been s
     url="/platforms/dotnet/guides/serilog/logs/"
     skill="sentry-dotnet-sdk"
   />
+- <LinkWithPlatformIcon
+    platform="dotnet.log4net"
+    label="log4net"
+    url="/platforms/dotnet/guides/log4net/logs/"
+    skill="sentry-dotnet-sdk"
+  />
 
 ### Native
 

platform-includes/logs/integrations/dotnet.mdx

@@ -4,6 +4,7 @@ Available integrations:
 <IntegrationListItem href="/platforms/dotnet/guides/maui/logs/">.NET Multi-platform App UI (.NET MAUI)</IntegrationListItem>
 <IntegrationListItem href="/platforms/dotnet/guides/extensions-logging/logs/">Microsoft.Extensions.Logging</IntegrationListItem>
 <IntegrationListItem href="/platforms/dotnet/guides/serilog/logs/">Serilog</IntegrationListItem>
+<IntegrationListItem href="/platforms/dotnet/guides/log4net/logs/">log4net</IntegrationListItem>
 </ul>
 
 If there's an integration you would like to see, open a [new issue on GitHub](https://github.com/getsentry/sentry-dotnet/issues/new/choose).

platform-includes/logs/options/dotnet.mdx

@@ -1,6 +1,6 @@
 #### EnableLogs
 
-<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog"]}>
+<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog", "dotnet.log4net"]}>
 Set to `true` in order to enable the `SentrySdk.Logger` APIs.
 </PlatformSection>
 
@@ -12,6 +12,10 @@ Set to `true` in order to enable the logging integration via the `ILogger<TCateg
 Set to `true` in order to enable the logging integration via the `Log`/`Logger` APIs.
 </PlatformSection>
 
+<PlatformSection supported={["dotnet.log4net"]}>
+Set to `true` in order to enable the logging integration via the log4net `ILog` APIs.
+</PlatformSection>
+
 <PlatformSection supported={["dotnet.aspnetcore", "dotnet.aws-lambda", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui"]}>
 
 #### Configure Microsoft.Extensions.Logging Filters

platform-includes/logs/requirements/dotnet.mdx

@@ -1,7 +1,11 @@
-<PlatformSection notSupported={["dotnet.serilog"]}>
+<PlatformSection notSupported={["dotnet.serilog", "dotnet.log4net"]}>
 Logs for <PlatformOrGuideName/> are supported in Sentry <PlatformOrGuideName/> SDK version `5.14.0` and above.
 </PlatformSection>
 
 <PlatformSection supported={["dotnet.serilog"]}>
 Logs for <PlatformOrGuideName/> are supported in Sentry <PlatformOrGuideName/> SDK version `5.16.0` and above.
 </PlatformSection>
+
+<PlatformSection supported={["dotnet.log4net"]}>
+Logs for <PlatformOrGuideName/> are supported in Sentry <PlatformOrGuideName/> SDK version `6.8.0` and above.
+</PlatformSection>

platform-includes/logs/setup/dotnet.mdx

@@ -1,6 +1,6 @@
 To enable logging, you need to initialize the SDK with the `EnableLogs` option set to `true`.
 
-<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.aws-lambda", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog"]}>
+<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.aws-lambda", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog", "dotnet.log4net"]}>
 
 ```csharp
 SentrySdk.Init(options =>
@@ -70,6 +70,23 @@ This enables the `SentrySdk.Logger` APIs, as well as the `Microsoft.Extensions.L
 ```
 
 
+</PlatformSection>
+
+<PlatformSection supported={["dotnet.log4net"]}>
+
+`EnableLogs` isn't exposed as a log4net appender setting, so initialize the SDK with `SentrySdk.Init` and leave the DSN out of your log4net appender configuration.
+
+```csharp
+SentrySdk.Init(options =>
+{
+    options.Dsn = "___PUBLIC_DSN___";
+    // Enable logs to be sent to Sentry
+    options.EnableLogs = true;
+});
+```
+
+The `SentryAppender` configured in your log4net configuration then captures logs without initializing the SDK itself. If the SDK is initialized elsewhere (for example, through ASP.NET Core), enable `EnableLogs` on those options instead.
+
 </PlatformSection>
 
 It does _not_ capture the `Console.WriteLine()` standard output stream.

platform-includes/logs/usage/dotnet.mdx

@@ -1,4 +1,4 @@
-<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog"]}>
+<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog", "dotnet.log4net"]}>
 
 Once the feature is enabled on the SDK and the SDK is initialized, you can send logs using the `SentrySdk.Logger` APIs.
 
@@ -81,7 +81,42 @@ The _Enrichments_ of _log events_ are attached as attributes to the logs, alongs
 
 </PlatformSection>
 
-<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog"]}>
+<PlatformSection supported={["dotnet.log4net"]}>
+
+Once the feature is enabled on the SDK and the SDK is initialized, you can send logs using the _log4net_ APIs, for example through the `ILog` methods (`Debug`, `Info`, `Warn`, `Error`, and `Fatal`).
+
+log4net levels are automatically mapped to Sentry's severity:
+
+| log4net.Core.Level | Sentry.SentryLogLevel | Sentry Logs UI Severity |
+| --- | --- | --- |
+| Trace | Trace | trace |
+| Debug | Debug | debug |
+| Info | Info | info |
+| Warn | Warning | warn |
+| Error | Error | error |
+| Fatal | Fatal | fatal |
+
+These properties will be sent to Sentry, and can be searched from within the Logs UI, and even added to the Logs views as a dedicated column.
+
+```csharp
+private static readonly ILog Log = LogManager.GetLogger(typeof(Program));
+
+Log.Info("A simple log message");
+Log.Error("An error log message");
+
+ThreadContext.Properties["Property"] = "Value";
+Log.Warn("Message with a custom property");
+```
+
+The log4net _properties_ (from the log event, `ThreadContext`, and `GlobalContext`) are attached as `property.<name>` attributes to the logs, alongside a set of default attributes automatically provided by the SDK. The logger name is attached as the `category.name` attribute.
+
+The `SentryAppender`'s `Environment` and `SendIdentity` settings also apply to structured logs: when configured, `Environment` sets the log's environment and `SendIdentity` attaches the log4net identity as the user.
+
+Because log4net renders each message before it reaches the appender, structured logs from log4net carry the fully-formatted message but no message template or parameters.
+
+</PlatformSection>
+
+<PlatformSection notSupported={["dotnet.aspnetcore", "dotnet.azure-functions-worker", "dotnet.blazor-webassembly", "dotnet.extensions-logging", "dotnet.maui", "dotnet.serilog", "dotnet.log4net"]}>
 
 The SDK automatically provides a set of default attributes attached to your logs.
 Additionally, you can attach custom attributes via a delegate.