✨ introduce tracer for stdout, stderr, nowrite

Author: davidB

Cargo.toml

@@ -43,5 +43,6 @@ tracing-subscriber = { version = "0.3", default-features = false, features = [
 
 
 [features]
-jaeger = ["opentelemetry-jaeger", "opentelemetry-semantic-conventions"]
-otlp = ["opentelemetry-otlp", "opentelemetry-semantic-conventions"]
+jaeger = ["opentelemetry-jaeger", "tracer"]
+otlp = ["opentelemetry-otlp", "tracer"]
+tracer = ["opentelemetry-semantic-conventions"]

src/tools/mod.rs

@@ -2,29 +2,41 @@
 use opentelemetry::sdk::Resource;
 #[cfg(any(feature = "jaeger", feature = "otlp"))]
 use opentelemetry::{sdk::trace as sdktrace, trace::TraceError};
-#[cfg(any(feature = "jaeger", feature = "otlp"))]
+#[cfg(feature = "tracer")]
 use opentelemetry_semantic_conventions as semcov;
 
 #[cfg(feature = "jaeger")]
-mod jaeger;
+pub mod jaeger;
 #[cfg(feature = "otlp")]
-mod otlp;
+pub mod otlp;
+#[cfg(feature = "tracer")]
+pub mod write;
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub enum CollectorKind {
     #[cfg(feature = "otlp")]
     Otlp,
     #[cfg(feature = "jaeger")]
     Jaeger,
-    // Stdout,
+    #[cfg(feature = "tracer")]
+    Stdout,
+    #[cfg(feature = "tracer")]
+    Stderr,
+    #[cfg(feature = "tracer")]
+    NoWrite,
 }
 
-#[cfg(any(feature = "jaeger", feature = "otlp"))]
+#[cfg(feature = "tracer")]
 pub fn init_tracer(
     kind: CollectorKind,
     resource: Resource,
 ) -> Result<sdktrace::Tracer, TraceError> {
     match kind {
+        CollectorKind::Stdout => write::init_tracer(resource, write::identity, std::io::stdout()),
+        CollectorKind::Stderr => write::init_tracer(resource, write::identity, std::io::stderr()),
+        CollectorKind::NoWrite => {
+            write::init_tracer(resource, write::identity, write::WriteNoWhere::default())
+        }
         #[cfg(feature = "otlp")]
         CollectorKind::Otlp => {
             // if let Some(url) = std::env::var_os("OTEL_COLLECTOR_URL")
@@ -52,7 +64,7 @@ pub fn init_tracer(
 /// # }
 ///
 /// ```
-#[cfg(any(feature = "jaeger", feature = "otlp"))]
+#[cfg(feature = "tracer")]
 pub fn make_resource<S>(service_name: S, service_version: S) -> Resource
 where
     S: Into<String>,

src/tools/write.rs

@@ -0,0 +1,44 @@
+use opentelemetry::sdk::export::trace::stdout::PipelineBuilder;
+use opentelemetry::sdk::Resource;
+use opentelemetry::{
+    global, sdk::propagation::TraceContextPropagator, sdk::trace as sdktrace, trace::TraceError,
+};
+use std::fmt::Debug;
+use std::io::Write;
+
+pub fn identity<W: Write>(v: PipelineBuilder<W>) -> PipelineBuilder<W> {
+    v
+}
+
+pub fn init_tracer<F, W>(
+    resource: Resource,
+    transform: F,
+    w: W,
+) -> Result<sdktrace::Tracer, TraceError>
+where
+    F: FnOnce(PipelineBuilder<W>) -> PipelineBuilder<W>,
+    W: Write + Debug + Send + 'static,
+{
+    global::set_text_map_propagator(TraceContextPropagator::new());
+
+    let mut pipeline = PipelineBuilder::default().with_writer(w).with_trace_config(
+        sdktrace::config()
+            .with_resource(resource)
+            .with_sampler(sdktrace::Sampler::AlwaysOn),
+    );
+    pipeline = transform(pipeline);
+    Ok(pipeline.install_simple())
+}
+
+#[derive(Debug, Default)]
+pub struct WriteNoWhere;
+
+impl Write for WriteNoWhere {
+    fn write(&mut self, _buf: &[u8]) -> std::io::Result<usize> {
+        Ok(0)
+    }
+
+    fn flush(&mut self) -> std::io::Result<()> {
+        Ok(())
+    }
+}