refactor(telemetry): make bunyan as a feature

src/telemetry.rs

@@ -1,14 +1,31 @@
+#[cfg(feature = "bunyan")]
 use tracing_bunyan_formatter::{BunyanFormattingLayer, JsonStorageLayer};
 use tracing_subscriber::{EnvFilter, layer::SubscriberExt, util::SubscriberInitExt};
 
 /// Initialise tracing with bunyan-style JSON output.
+#[cfg(feature = "bunyan")]
 pub fn setup_logger() {
-    let env_filter = EnvFilter::try_from_default_env().unwrap_or_else(|_| "info".into());
+    let env_filter = create_env_filter();
     let formatter = BunyanFormattingLayer::new("tg-relay-rs".into(), std::io::stdout);
 
     tracing_subscriber::registry()
         .with(env_filter)
-        .with(JsonStorageLayer)
         .with(formatter)
-        .init();
+        .with(JsonStorageLayer)
+        .init()
+}
+
+#[cfg(not(feature = "bunyan"))]
+pub fn setup_logger() {
+    let env_filter = create_env_filter();
+    let formatter = tracing_subscriber::fmt::Layer::default();
+
+    tracing_subscriber::registry()
+        .with(env_filter)
+        .with(formatter)
+        .init()
+}
+
+fn create_env_filter() -> EnvFilter {
+    EnvFilter::try_from_default_env().unwrap_or_else(|_| "info".into())
 }