chore: update metriken library

Updates the metriken metrics library to version 0.2.1 and converts
all metrics declarations to using the attribute macro. This will
allow us to easily add additional metric metadata later.

Cargo.toml

@@ -55,7 +55,7 @@ httparse = "1.8.0"
 libc = "0.2.139"
 log = "0.4.17"
 memmap2 = "0.5.8"
-metriken = "0.1.1"
+metriken = "0.2.1"
 metrohash = "1.0.6"
 mio = "0.8.5"
 nom = "7.1.3"
@@ -65,7 +65,7 @@ quote = "1.0.23"
 rand = "0.8.5"
 rand_chacha = "0.3.1"
 rand_xoshiro = "0.6.0"
-ringlog = "0.1.0"
+ringlog = "0.2.0"
 serde = "1.0.152"
 serde_json = "1.0.91"
 signal-hook = "0.3.15"

src/common/src/metrics.rs

@@ -27,7 +27,8 @@ macro_rules! test_no_duplicates {
 
 pub use test_no_duplicates;
 
-gauge!(PID, "the process id");
+#[metric(name = "pid", description = "the process id")]
+pub static PID: Gauge = Gauge::new();
 
 pub fn init() {
     PID.set(std::process::id().into());