Simplified stdout exporter for logs and traces (open-telemetry#2040)

Co-authored-by: Lalit Kumar Bhasin <[email protected]>
Co-authored-by: Utkarsh Umesan Pillai <[email protected]>

examples/logs-basic/src/main.rs

@@ -7,11 +7,7 @@ use opentelemetry_semantic_conventions::resource::SERVICE_NAME;
 
 fn main() {
     // Setup LoggerProvider with a stdout exporter
-    let exporter = opentelemetry_stdout::LogExporterBuilder::default()
-        // uncomment the below lines to pretty print output.
-        // .with_encoder(|writer, data|
-        //    Ok(serde_json::to_writer_pretty(writer, &data).unwrap()))
-        .build();
+    let exporter = opentelemetry_stdout::LogExporter::default();
     let logger_provider = LoggerProvider::builder()
         .with_resource(Resource::new([KeyValue::new(
             SERVICE_NAME,

examples/tracing-grpc/src/client.rs

@@ -4,7 +4,7 @@ use opentelemetry::{global, propagation::Injector};
 use opentelemetry_sdk::{
     propagation::TraceContextPropagator, runtime::Tokio, trace::TracerProvider,
 };
-use opentelemetry_stdout::SpanExporterBuilder;
+use opentelemetry_stdout::SpanExporter;
 
 use opentelemetry::{
     trace::{SpanKind, TraceContextExt, Tracer},
@@ -15,15 +15,7 @@ fn init_tracer() {
     global::set_text_map_propagator(TraceContextPropagator::new());
     // Install stdout exporter pipeline to be able to retrieve the collected spans.
     let provider = TracerProvider::builder()
-        .with_batch_exporter(
-            SpanExporterBuilder::default()
-                .with_encoder(|writer, data| {
-                    serde_json::to_writer_pretty(writer, &data).unwrap();
-                    Ok(())
-                })
-                .build(),
-            Tokio,
-        )
+        .with_batch_exporter(SpanExporter::default(), Tokio)
         .build();
 
     global::set_tracer_provider(provider);

examples/tracing-grpc/src/server.rs

@@ -8,22 +8,14 @@ use opentelemetry::{
 use opentelemetry_sdk::{
     propagation::TraceContextPropagator, runtime::Tokio, trace::TracerProvider,
 };
-use opentelemetry_stdout::SpanExporterBuilder;
+use opentelemetry_stdout::SpanExporter;
 use tonic::{transport::Server, Request, Response, Status};
 
 fn init_tracer() {
     global::set_text_map_propagator(TraceContextPropagator::new());
     // Install stdout exporter pipeline to be able to retrieve the collected spans.
     let provider = TracerProvider::builder()
-        .with_batch_exporter(
-            SpanExporterBuilder::default()
-                .with_encoder(|writer, data| {
-                    serde_json::to_writer_pretty(writer, &data).unwrap();
-                    Ok(())
-                })
-                .build(),
-            Tokio,
-        )
+        .with_batch_exporter(SpanExporter::default(), Tokio)
         .build();
 
     global::set_tracer_provider(provider);

opentelemetry-appender-log/src/lib.rs

@@ -12,7 +12,7 @@
 //! # #[tokio::main] async fn main() {
 //! # use opentelemetry_sdk::logs::{BatchLogProcessor, LoggerProvider};
 //! # use opentelemetry_sdk::runtime;
-//! let exporter = opentelemetry_stdout::LogExporterBuilder::default().build();
+//! let exporter = opentelemetry_stdout::LogExporter::default();
 //!
 //! let logger_provider = LoggerProvider::builder()
 //!     .with_log_processor(BatchLogProcessor::builder(exporter, runtime::Tokio).build())
@@ -27,7 +27,7 @@
 //! # use opentelemetry_sdk::logs::{BatchLogProcessor, LoggerProvider};
 //! # use opentelemetry_sdk::runtime;
 //! # use opentelemetry_appender_log::OpenTelemetryLogBridge;
-//! # let exporter = opentelemetry_stdout::LogExporterBuilder::default().build();
+//! # let exporter = opentelemetry_stdout::LogExporter::default();
 //! # let logger_provider = LoggerProvider::builder()
 //! #     .with_log_processor(BatchLogProcessor::builder(exporter, runtime::Tokio).build())
 //! #     .build();

opentelemetry-stdout/CHANGELOG.md

@@ -4,6 +4,10 @@
 
 - **Breaking** [1994](https://github.com/open-telemetry/opentelemetry-rust/pull/1994) The logrecord event-name is added as attribute with
 key `name` only if the feature flag `populate-logs-event-name` is enabled.
+- **Breaking** [2040](https://github.com/open-telemetry/opentelemetry-rust/pull/2040) Simplified stdout exporter:
+  - Now only supports writing to stdout, removing ability to send telemetry to other streams.
+  - Output format improved for better human readability.
+  - Note: This exporter is intended for learning and debugging purposes only. Not recommended for production use or automated parsing.
 
 ## v0.5.0
 

opentelemetry-stdout/examples/basic.rs

@@ -64,21 +64,129 @@ fn init_logs() -> opentelemetry_sdk::logs::LoggerProvider {
 
 #[cfg(feature = "trace")]
 fn emit_span() {
-    let tracer = global::tracer("stdout-test");
-    let mut span = tracer.start("test_span");
-    span.set_attribute(KeyValue::new("test_key", "test_value"));
+    use opentelemetry::trace::{
+        SpanContext, SpanId, TraceFlags, TraceId, TraceState, TracerProvider,
+    };
+
+    let tracer = global::tracer_provider()
+        .tracer_builder("stdout-example")
+        .with_version("v1")
+        .with_schema_url("schema_url")
+        .with_attributes([KeyValue::new("scope_key", "scope_value")])
+        .build();
+    let mut span = tracer.start("example-span");
+    span.set_attribute(KeyValue::new("attribute_key1", "attribute_value1"));
+    span.set_attribute(KeyValue::new("attribute_key2", "attribute_value2"));
     span.add_event(
-        "test_event",
-        vec![KeyValue::new("test_event_key", "test_event_value")],
+        "example-event-name",
+        vec![KeyValue::new("event_attribute1", "event_value1")],
+    );
+    span.add_link(
+        SpanContext::new(
+            TraceId::from_hex("58406520a006649127e371903a2de979").expect("invalid"),
+            SpanId::from_hex("b6d7d7f6d7d6d7f6").expect("invalid"),
+            TraceFlags::default(),
+            false,
+            TraceState::NONE,
+        ),
+        vec![
+            KeyValue::new("link_attribute1", "link_value1"),
+            KeyValue::new("link_attribute2", "link_value2"),
+        ],
+    );
+
+    span.add_link(
+        SpanContext::new(
+            TraceId::from_hex("23401120a001249127e371903f2de971").expect("invalid"),
+            SpanId::from_hex("cd37d765d743d7f6").expect("invalid"),
+            TraceFlags::default(),
+            false,
+            TraceState::NONE,
+        ),
+        vec![
+            KeyValue::new("link_attribute1", "link_value1"),
+            KeyValue::new("link_attribute2", "link_value2"),
+        ],
     );
     span.end();
 }
 
 #[cfg(feature = "metrics")]
 fn emit_metrics() {
-    let meter = global::meter("stdout-test");
-    let c = meter.u64_counter("test_counter").init();
-    c.add(1, &[KeyValue::new("test_key", "test_value")]);
+    let meter = global::meter("stdout-example");
+    let c = meter.u64_counter("example_counter").init();
+    c.add(
+        1,
+        &[
+            KeyValue::new("name", "apple"),
+            KeyValue::new("color", "green"),
+        ],
+    );
+    c.add(
+        1,
+        &[
+            KeyValue::new("name", "apple"),
+            KeyValue::new("color", "green"),
+        ],
+    );
+    c.add(
+        2,
+        &[
+            KeyValue::new("name", "apple"),
+            KeyValue::new("color", "red"),
+        ],
+    );
+    c.add(
+        1,
+        &[
+            KeyValue::new("name", "banana"),
+            KeyValue::new("color", "yellow"),
+        ],
+    );
+    c.add(
+        11,
+        &[
+            KeyValue::new("name", "banana"),
+            KeyValue::new("color", "yellow"),
+        ],
+    );
+
+    let h = meter.f64_histogram("example_histogram").init();
+    h.record(
+        1.0,
+        &[
+            KeyValue::new("name", "apple"),
+            KeyValue::new("color", "green"),
+        ],
+    );
+    h.record(
+        1.0,
+        &[
+            KeyValue::new("name", "apple"),
+            KeyValue::new("color", "green"),
+        ],
+    );
+    h.record(
+        2.0,
+        &[
+            KeyValue::new("name", "apple"),
+            KeyValue::new("color", "red"),
+        ],
+    );
+    h.record(
+        1.0,
+        &[
+            KeyValue::new("name", "banana"),
+            KeyValue::new("color", "yellow"),
+        ],
+    );
+    h.record(
+        11.0,
+        &[
+            KeyValue::new("name", "banana"),
+            KeyValue::new("color", "yellow"),
+        ],
+    );
 }
 
 #[cfg(feature = "logs")]
@@ -101,17 +209,9 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     #[cfg(feature = "logs")]
     emit_log();
 
-    println!(
-        "======================================================================================"
-    );
-
     #[cfg(feature = "trace")]
     emit_span();
 
-    println!(
-        "======================================================================================"
-    );
-
     #[cfg(feature = "metrics")]
     emit_metrics();
 

opentelemetry-stdout/src/lib.rs

@@ -7,7 +7,7 @@
 //! # Feature Flags
 //! The following feature flags can enable exporters for different telemetry signals:
 //!
-//! * `trace`: Includes the trace exporters (enabled by default).
+//! * `trace`: Includes the trace exporters.
 //! * `metrics`: Includes the metrics exporters.
 //! * `logs`: Includes the logs exporters.
 //!
@@ -56,9 +56,6 @@
 //!
 //! // recorded traces, metrics and logs will now be sent to stdout:
 //!
-//! // {"resourceMetrics":{"resource":{"attributes":[{"key":"service.name","value":{"str..
-//! // {"resourceSpans":[{"resource":{"attributes":[{"key":"service.name","value":{"stri..
-//! // {"resourceLogs": [{"resource": {"attributes": [{"key": "service.name", "value": {"str..
 //! # }
 //! ```
 #![warn(missing_debug_implementations, missing_docs)]