feat: Support for sending logs through OTLP (#21039)

Co-authored-by: Matthias Seitz <matthias.seitz@outlook.de>

crates/node/core/src/args/mod.rs

@@ -26,7 +26,7 @@ pub use log::{ColorMode, LogArgs, Verbosity};
 
 /// `TraceArgs` for tracing and spans support
 mod trace;
-pub use trace::{OtlpInitStatus, TraceArgs};
+pub use trace::{OtlpInitStatus, OtlpLogsStatus, TraceArgs};
 
 /// `MetricArgs` to configure metrics.
 mod metric;

crates/node/core/src/args/trace.rs

@@ -1,4 +1,4 @@
-//! Opentelemetry tracing configuration through CLI args.
+//! Opentelemetry tracing and logging configuration through CLI args.
 
 use clap::Parser;
 use eyre::WrapErr;
@@ -6,7 +6,7 @@ use reth_tracing::{tracing_subscriber::EnvFilter, Layers};
 use reth_tracing_otlp::OtlpProtocol;
 use url::Url;
 
-/// CLI arguments for configuring `Opentelemetry` trace and span export.
+/// CLI arguments for configuring `Opentelemetry` trace and logs export.
 #[derive(Debug, Clone, Parser)]
 pub struct TraceArgs {
     /// Enable `Opentelemetry` tracing export to an OTLP endpoint.
@@ -30,9 +30,29 @@ pub struct TraceArgs {
     )]
     pub otlp: Option<Url>,
 
-    /// OTLP transport protocol to use for exporting traces.
+    /// Enable `Opentelemetry` logs export to an OTLP endpoint.
     ///
-    /// - `http`: expects endpoint path to end with `/v1/traces`
+    /// If no value provided, defaults based on protocol:
+    /// - HTTP: `http://localhost:4318/v1/logs`
+    /// - gRPC: `http://localhost:4317`
+    ///
+    /// Example: --logs-otlp=http://collector:4318/v1/logs
+    #[arg(
+        long = "logs-otlp",
+        env = "OTEL_EXPORTER_OTLP_LOGS_ENDPOINT",
+        global = true,
+        value_name = "URL",
+        num_args = 0..=1,
+        default_missing_value = "http://localhost:4318/v1/logs",
+        require_equals = true,
+        value_parser = parse_otlp_endpoint,
+        help_heading = "Logging"
+    )]
+    pub logs_otlp: Option<Url>,
+
+    /// OTLP transport protocol to use for exporting traces and logs.
+    ///
+    /// - `http`: expects endpoint path to end with `/v1/traces` or `/v1/logs`
     /// - `grpc`: expects endpoint without a path
     ///
     /// Defaults to HTTP if not specified.
@@ -62,6 +82,22 @@ pub struct TraceArgs {
     )]
     pub otlp_filter: EnvFilter,
 
+    /// Set a filter directive for the OTLP logs exporter. This controls the verbosity
+    /// of logs sent to the OTLP endpoint. It follows the same syntax as the
+    /// `RUST_LOG` environment variable.
+    ///
+    /// Example: --logs-otlp.filter=info,reth=debug
+    ///
+    /// Defaults to INFO if not specified.
+    #[arg(
+        long = "logs-otlp.filter",
+        global = true,
+        value_name = "FILTER",
+        default_value = "info",
+        help_heading = "Logging"
+    )]
+    pub logs_otlp_filter: EnvFilter,
+
     /// Service name to use for OTLP tracing export.
     ///
     /// This name will be used to identify the service in distributed tracing systems
@@ -101,8 +137,10 @@ impl Default for TraceArgs {
     fn default() -> Self {
         Self {
             otlp: None,
+            logs_otlp: None,
             protocol: OtlpProtocol::Http,
             otlp_filter: EnvFilter::from_default_env(),
+            logs_otlp_filter: EnvFilter::try_new("info").expect("valid filter"),
             sample_ratio: None,
             service_name: "reth".to_string(),
         }
@@ -150,6 +188,37 @@ impl TraceArgs {
             Ok(OtlpInitStatus::Disabled)
         }
     }
+
+    /// Initialize OTLP logs export with the given layers.
+    ///
+    /// This method handles OTLP logs initialization based on the configured options,
+    /// including validation and protocol selection.
+    ///
+    /// Returns the initialization status to allow callers to log appropriate messages.
+    pub async fn init_otlp_logs(&mut self, _layers: &mut Layers) -> eyre::Result<OtlpLogsStatus> {
+        if let Some(endpoint) = self.logs_otlp.as_mut() {
+            self.protocol.validate_logs_endpoint(endpoint)?;
+
+            #[cfg(feature = "otlp-logs")]
+            {
+                let config = reth_tracing_otlp::OtlpLogsConfig::new(
+                    self.service_name.clone(),
+                    endpoint.clone(),
+                    self.protocol,
+                )?;
+
+                _layers.with_log_layer(config.clone(), self.logs_otlp_filter.clone())?;
+
+                Ok(OtlpLogsStatus::Started(config.endpoint().clone()))
+            }
+            #[cfg(not(feature = "otlp-logs"))]
+            {
+                Ok(OtlpLogsStatus::NoFeature)
+            }
+        } else {
+            Ok(OtlpLogsStatus::Disabled)
+        }
+    }
 }
 
 /// Status of OTLP tracing initialization.
@@ -163,6 +232,17 @@ pub enum OtlpInitStatus {
     NoFeature,
 }
 
+/// Status of OTLP logs initialization.
+#[derive(Debug)]
+pub enum OtlpLogsStatus {
+    /// OTLP logs export was successfully started with the given endpoint.
+    Started(Url),
+    /// OTLP logs export is disabled (no endpoint configured).
+    Disabled,
+    /// OTLP logs arguments provided but feature is not compiled.
+    NoFeature,
+}
+
 // Parses an OTLP endpoint url.
 fn parse_otlp_endpoint(arg: &str) -> eyre::Result<Url> {
     Url::parse(arg).wrap_err("Invalid URL for OTLP trace output")