Add graphs for each function name (#4214)

substrate/client/grafana-data-source/src/lib.rs

@@ -36,7 +36,7 @@ mod networking;
 pub use server::run_server;
 pub use util::now_millis;
 
-type Metrics = HashMap<&'static str, Vec<(f32, i64)>>;
+type Metrics = HashMap<String, Vec<(f32, i64)>>;
 
 lazy_static! {
 	/// The `RwLock` wrapping the metrics. Not intended to be used directly.

substrate/client/grafana-data-source/test/src/main.rs

@@ -26,8 +26,8 @@ async fn randomness() {
 		let random = rand::thread_rng().gen_range(0.0, 1000.0);
 
 		record_metrics!(
-			"random data" => random,
-			"random^2" => random * random
+			"random data".to_owned() => random,
+			"random^2".to_owned() => random * random
 		);
 	}
 }