Add new layer to add env vars to span attributes

Cargo.toml

@@ -9,7 +9,7 @@ repository = "https://github.com/primait/prima_tracing.rs"
 version = "0.9.1"
 
 [features]
-default = []
+default = ["live", "dev"]
 # Legacy feature names kept for compatibility reasons
 prima-logger-datadog = ["datadog"]
 prima-logger-json = ["json-logger"]

src/layer/kube_env.rs

@@ -0,0 +1,52 @@
+use opentelemetry::KeyValue;
+use tracing::{span, Subscriber};
+use tracing_opentelemetry::OtelData;
+use tracing_subscriber::{layer::Context, Layer};
+
+// Extracts KUBE_APP_PART_OF, KUBE_APP_MANAGED_BY, KUBE_APP_VERSION and KUBE_APP_INSTANCE from the environment
+// and adds them to span attributes
+pub struct KubeEnvLayer {
+    pub kube_app_part_of: Option<String>,
+    pub kube_app_managed_by: Option<String>,
+    pub kube_app_version: Option<String>,
+    pub kube_app_instance: Option<String>,
+}
+
+impl Default for KubeEnvLayer {
+    fn default() -> Self {
+        Self {
+            kube_app_part_of: std::env::var("KUBE_APP_PART_OF").ok(),
+            kube_app_managed_by: std::env::var("KUBE_APP_MANAGED_BY").ok(),
+            kube_app_version: std::env::var("KUBE_APP_VERSION").ok(),
+            kube_app_instance: std::env::var("KUBE_APP_INSTANCE").ok(),
+        }
+    }
+}
+
+impl<S> Layer<S> for KubeEnvLayer
+where
+    S: Subscriber + for<'a> tracing_subscriber::registry::LookupSpan<'a>,
+{
+    fn on_new_span(&self, _attrs: &span::Attributes<'_>, id: &span::Id, ctx: Context<'_, S>) {
+        let span = ctx.span(id).expect("Span not found, this is a bug");
+        let mut extensions = span.extensions_mut();
+
+        if let Some(otel_data) = extensions.get_mut::<OtelData>() {
+            let builder = &mut otel_data.builder;
+            if let Some(ref mut attributes) = builder.attributes {
+                if let Some(ref part_of) = self.kube_app_part_of {
+                    attributes.push(KeyValue::new("kube_app_part_of", part_of.clone()));
+                }
+                if let Some(ref managed_by) = self.kube_app_managed_by {
+                    attributes.push(KeyValue::new("kube_app_managed_by", managed_by.clone()));
+                }
+                if let Some(ref version) = self.kube_app_version {
+                    attributes.push(KeyValue::new("kube_app_version", version.clone()));
+                }
+                if let Some(ref instance) = self.kube_app_instance {
+                    attributes.push(KeyValue::new("kube_app_instance", instance.clone()));
+                }
+            }
+        }
+    }
+}

src/layer/mod.rs

@@ -1,5 +1,7 @@
 pub use error::ErrorLayer;
+pub use kube_env::KubeEnvLayer;
 pub use version::VersionLayer;
 
 mod error;
+mod kube_env;
 mod version;

src/subscriber.rs

@@ -31,6 +31,7 @@ pub fn configure_subscriber<T: EventFormatter + Send + Sync + 'static>(
                 version: _config.version.clone(),
             })
             .with(crate::layer::ErrorLayer)
+            .with(crate::layer::KubeEnvLayer::default())
     };
 
     #[cfg(not(feature = "json-logger"))]
@@ -40,7 +41,8 @@ pub fn configure_subscriber<T: EventFormatter + Send + Sync + 'static>(
         use crate::json::formatter::PrimaFormattingLayer;
         use crate::json::storage::PrimaJsonStorage;
         subscriber
-            .with(PrimaJsonStorage)
+            .with(PrimaJsonStorage::default())
+            .with(crate::layer::KubeEnvLayer::default())
             .with(PrimaFormattingLayer::new(
                 _config.service.clone(),
                 _config.country.to_string(),