Add exprimental flag for OTLP logs integration

cmd/traefik/logger.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	stdlog "log"
@@ -22,6 +23,14 @@ func init() {
 }
 
 func setupLogger(staticConfiguration *static.Configuration) error {
+	// Validate that the experimental flag is set up at this point,
+	// rather than validating the static configuration before the setupLogger call.
+	// This ensures that validation messages are not logged using an un-configured logger.
+	if staticConfiguration.Log != nil && staticConfiguration.Log.OTLP != nil &&
+		(staticConfiguration.Experimental == nil || !staticConfiguration.Experimental.OTLPLogs) {
+		return errors.New("the experimental OTLPLogs feature must be enabled to use OTLP logging")
+	}
+
 	// configure log format
 	w := getLogWriter(staticConfiguration)
 

docs/content/observability/access-logs.md

@@ -308,6 +308,23 @@ services:
 
 ## OpenTelemetry
 
+!!! warning "Experimental Feature"
+
+    The OpenTelemetry access logs feature is currently experimental and must be explicitly enabled in the experimental section prior to use.
+    
+    ```yaml tab="File (YAML)"
+    experimental:
+      otlpLogs: true
+    ```
+    
+    ```toml tab="File (TOML)"
+    [experimental.otlpLogs]
+    ```
+    
+    ```bash tab="CLI"
+    --experimental.otlpLogs=true
+    ```
+
 To enable the OpenTelemetry Logger for access logs:
 
 ```yaml tab="File (YAML)"

docs/content/observability/logs.md

@@ -183,6 +183,23 @@ log:
 
 ## OpenTelemetry
 
+!!! warning "Experimental Feature"
+    
+    The OpenTelemetry logs feature is currently experimental and must be explicitly enabled in the experimental section prior to use.
+    
+    ```yaml tab="File (YAML)"
+    experimental:
+      otlpLogs: true
+    ```
+    
+    ```toml tab="File (TOML)"
+    [experimental.otlpLogs]
+    ```
+    
+    ```bash tab="CLI"
+    --experimental.otlpLogs=true
+    ```
+
 To enable the OpenTelemetry Logger for logs:
 
 ```yaml tab="File (YAML)"

docs/content/reference/static-configuration/cli-ref.md

@@ -313,7 +313,7 @@ Timeout defines how long to wait on an idle session before releasing the related
 Defines whether all plugins must be loaded successfully for Traefik to start. (Default: ```false```)
 
 `--experimental.fastproxy`:  
-Enable the FastProxy implementation. (Default: ```false```)
+Enables the FastProxy implementation. (Default: ```false```)
 
 `--experimental.fastproxy.debug`:  
 Enable debug mode for the FastProxy implementation. (Default: ```false```)
@@ -336,6 +336,9 @@ Environment variables to forward to the wasm guest.
 `--experimental.localplugins.<name>.settings.mounts`:  
 Directory to mount to the wasm guest.
 
+`--experimental.otlplogs`:  
+Enables the OpenTelemetry logs integration. (Default: ```false```)
+
 `--experimental.plugins.<name>.modulename`:  
 plugin's module name.
 

docs/content/reference/static-configuration/env-ref.md

@@ -313,7 +313,7 @@ Timeout defines how long to wait on an idle session before releasing the related
 Defines whether all plugins must be loaded successfully for Traefik to start. (Default: ```false```)
 
 `TRAEFIK_EXPERIMENTAL_FASTPROXY`:  
-Enable the FastProxy implementation. (Default: ```false```)
+Enables the FastProxy implementation. (Default: ```false```)
 
 `TRAEFIK_EXPERIMENTAL_FASTPROXY_DEBUG`:  
 Enable debug mode for the FastProxy implementation. (Default: ```false```)
@@ -336,6 +336,9 @@ Environment variables to forward to the wasm guest.
 `TRAEFIK_EXPERIMENTAL_LOCALPLUGINS_<NAME>_SETTINGS_MOUNTS`:  
 Directory to mount to the wasm guest.
 
+`TRAEFIK_EXPERIMENTAL_OTLPLOGS`:  
+Enables the OpenTelemetry logs integration. (Default: ```false```)
+
 `TRAEFIK_EXPERIMENTAL_PLUGINS_<NAME>_MODULENAME`:  
 plugin's module name.
 

docs/content/reference/static-configuration/file.toml

@@ -559,6 +559,7 @@
 
 [experimental]
   abortOnPluginFailure = true
+  otlplogs = true
   kubernetesGateway = true
   [experimental.plugins]
     [experimental.plugins.Descriptor0]

docs/content/reference/static-configuration/file.yaml

@@ -649,6 +649,7 @@ experimental:
   abortOnPluginFailure: true
   fastProxy:
     debug: true
+  otlplogs: true
   kubernetesGateway: true
 core:
   defaultRuleSyntax: foobar

pkg/config/static/experimental.go

@@ -7,8 +7,8 @@ type Experimental struct {
 	Plugins              map[string]plugins.Descriptor      `description:"Plugins configuration." json:"plugins,omitempty" toml:"plugins,omitempty" yaml:"plugins,omitempty" export:"true"`
 	LocalPlugins         map[string]plugins.LocalDescriptor `description:"Local plugins configuration." json:"localPlugins,omitempty" toml:"localPlugins,omitempty" yaml:"localPlugins,omitempty" export:"true"`
 	AbortOnPluginFailure bool                               `description:"Defines whether all plugins must be loaded successfully for Traefik to start." json:"abortOnPluginFailure,omitempty" toml:"abortOnPluginFailure,omitempty" yaml:"abortOnPluginFailure,omitempty" export:"true"`
-
-	FastProxy *FastProxyConfig `description:"Enable the FastProxy implementation." json:"fastProxy,omitempty" toml:"fastProxy,omitempty" yaml:"fastProxy,omitempty" label:"allowEmpty" file:"allowEmpty" export:"true"`
+	FastProxy            *FastProxyConfig                   `description:"Enables the FastProxy implementation." json:"fastProxy,omitempty" toml:"fastProxy,omitempty" yaml:"fastProxy,omitempty" label:"allowEmpty" file:"allowEmpty" export:"true"`
+	OTLPLogs             bool                               `description:"Enables the OpenTelemetry logs integration." json:"otlplogs,omitempty" toml:"otlplogs,omitempty" yaml:"otlplogs,omitempty" export:"true"`
 
 	// Deprecated: KubernetesGateway provider is not an experimental feature starting with v3.1. Please remove its usage from the static configuration.
 	KubernetesGateway bool `description:"(Deprecated) Allow the Kubernetes gateway api provider usage." json:"kubernetesGateway,omitempty" toml:"kubernetesGateway,omitempty" yaml:"kubernetesGateway,omitempty" export:"true"`

pkg/config/static/static_config.go

@@ -387,12 +387,20 @@ func (c *Configuration) ValidateConfiguration() error {
 	}
 
 	if c.AccessLog != nil && c.AccessLog.OTLP != nil {
+		if c.Experimental == nil || !c.Experimental.OTLPLogs {
+			return errors.New("the experimental OTLPLogs feature must be enabled to use OTLP access logging")
+		}
+
 		if c.AccessLog.OTLP.GRPC != nil && c.AccessLog.OTLP.GRPC.TLS != nil && c.AccessLog.OTLP.GRPC.Insecure {
 			return errors.New("access logs OTLP GRPC: TLS and Insecure options are mutually exclusive")
 		}
 	}
 
 	if c.Log != nil && c.Log.OTLP != nil {
+		if c.Experimental == nil || !c.Experimental.OTLPLogs {
+			return errors.New("the experimental OTLPLogs feature must be enabled to use OTLP logging")
+		}
+
 		if c.Log.OTLP.GRPC != nil && c.Log.OTLP.GRPC.TLS != nil && c.Log.OTLP.GRPC.Insecure {
 			return errors.New("logs OTLP GRPC: TLS and Insecure options are mutually exclusive")
 		}