feat(o11y): add opentelemetry-stdout feature

.helix/languages.toml

@@ -25,7 +25,7 @@ diagnostics.disabled = ["inactive-code"]
 hover.actions.enable = false
 
 [language-server.rust-analyzer.config.cargo]
-features = ["introspection", "integration"]
+features = ["introspection", "integration", "opentelemetry-stdout"]
 
 [language-server.rust-analyzer.config.check]
 command  = "clippy"

crates/synd_o11y/Cargo.toml

@@ -20,14 +20,19 @@ opentelemetry-appender-tracing     = { version = "0.3.0", default-features = fal
 opentelemetry-http                 = { version = "0.11.0" }
 opentelemetry-otlp                 = { version = "0.15.0", default-features = false, features = ["trace", "metrics", "logs", "grpc-tonic"] }
 opentelemetry-semantic-conventions = { version = "0.14.0" }
+opentelemetry-stdout               = { version = "0.3.0", optional = true, default-features = false, features = ["metrics"] }
 opentelemetry_sdk                  = { version = "0.22.1", features = ["logs", "rt-tokio"] }
 rand                               = { workspace = true }
 reqwest                            = { workspace = true }
 serde                              = { workspace = true, features = ["derive"] }
+serde_json                         = { workspace = true, optional = true }
 tracing                            = { workspace = true }
 tracing-opentelemetry              = { version = "0.23.0" }
 tracing-subscriber                 = { workspace = true }
 
+[features]
+opentelemetry-stdout = ["dep:opentelemetry-stdout", "dep:serde_json"]
+
 [lints]
 workspace = true
 

crates/synd_o11y/src/tracing_subscriber/otel_metrics/mod.rs

@@ -47,12 +47,27 @@ fn init_meter_provider(endpoint: impl Into<String>, resource: Resource) -> impl
         .build();
 
     let view = view();
-
-    let meter_provider = SdkMeterProvider::builder()
+    let meter_provider_builder = SdkMeterProvider::builder()
         .with_resource(resource)
         .with_reader(reader)
-        .with_view(view)
-        .build();
+        .with_view(view);
+
+    #[cfg(feature = "opentelemetry-stdout")]
+    let stdout_reader = {
+        let exporter = opentelemetry_stdout::MetricsExporterBuilder::default()
+            .with_encoder(|writer, data| {
+                serde_json::to_writer_pretty(writer, &data).unwrap();
+                Ok(())
+            })
+            .build();
+        PeriodicReader::builder(exporter, runtime::Tokio)
+            .with_interval(Duration::from_secs(60))
+            .build()
+    };
+    #[cfg(feature = "opentelemetry-stdout")]
+    let meter_provider_builder = meter_provider_builder.with_reader(stdout_reader);
+
+    let meter_provider = meter_provider_builder.build();
 
     global::set_meter_provider(meter_provider.clone());