Telemetry per node (#7463)

substrate/client/service/src/config.rs

@@ -96,6 +96,11 @@ pub struct Configuration {
 	/// External WASM transport for the telemetry. If `Some`, when connection to a telemetry
 	/// endpoint, this transport will be tried in priority before all others.
 	pub telemetry_external_transport: Option<ExtTransport>,
+	/// Telemetry handle.
+	///
+	/// This is a handle to a `TelemetryWorker` instance. It is used to initialize the telemetry for
+	/// a substrate node.
+	pub telemetry_handle: Option<sc_telemetry::TelemetryHandle>,
 	/// The default number of 64KB pages to allocate for Wasm execution
 	pub default_heap_pages: Option<u64>,
 	/// Should offchain workers be executed.
@@ -198,9 +203,22 @@ impl Configuration {
 	}
 
 	/// Returns the prometheus metrics registry, if available.
-	pub fn prometheus_registry<'a>(&'a self) -> Option<&'a Registry> {
+	pub fn prometheus_registry(&self) -> Option<&Registry> {
 		self.prometheus_config.as_ref().map(|config| &config.registry)
 	}
+
+	/// Returns the telemetry endpoints if any and if the telemetry handle exists.
+	pub(crate) fn telemetry_endpoints(&self) -> Option<&TelemetryEndpoints> {
+		if self.telemetry_handle.is_none() {
+			return None;
+		}
+
+		match self.telemetry_endpoints.as_ref() {
+			// Don't initialise telemetry if `telemetry_endpoints` == Some([])
+			Some(endpoints) if !endpoints.is_empty() => Some(endpoints),
+			_ => None,
+		}
+	}
 }
 
 /// Available RPC methods.