Merge branch 'main' into perf-improve

Author: cijothomas

.github/workflows/ci.yml

@@ -62,10 +62,8 @@ jobs:
     - uses: arduino/setup-protoc@v3
       with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
-    - uses: actions-rs/cargo@v1
-      with:
-        command: fmt
-        args: --all -- --check
+    - name: Format
+      run: cargo fmt --all -- --check
     - name: Lint
       run: bash ./scripts/lint.sh
   external-types:

README.md

@@ -31,12 +31,12 @@ documentation.
 | Signal/Component      | Overall Status     |
 | --------------------  | ------------------ |
 | Context               | Beta               |
-| Baggage               | Beta               |
+| Baggage               | RC                 |
 | Propagators           | Beta               |
 | Logs-API              | Stable*            |
-| Logs-SDK              | RC                 |
+| Logs-SDK              | Stable              |
 | Logs-OTLP Exporter    | RC                 |
-| Logs-Appender-Tracing | RC                 |
+| Logs-Appender-Tracing | Stable             |
 | Metrics-API           | Stable             |
 | Metrics-SDK           | RC                 |
 | Metrics-OTLP Exporter | RC                 |

docs/migration_0.29.md

@@ -0,0 +1,92 @@
+# Migration Guide from 0.28 to 0.29
+
+OpenTelemetry Rust 0.29 introduces a few breaking changes. This guide aims to
+facilitate a smooth migration for common use cases involving the
+`opentelemetry`, `opentelemetry_sdk`, `opentelemetry-otlp`, and
+`opentelemetry-appender-tracing` crates. For a comprehensive list of changes,
+please refer to the detailed changelog for each crate. This document covers only
+the most common scenarios. Note that changes that only affect custom
+exporter/processor authors are not mentioned in this doc.
+
+OpenTelemetry Metrics API and Log-Bridge API were declared stable in 0.28, and have
+no breaking changes.
+
+## Baggage Changes
+
+The Baggage API has been redesigned to align with the OpenTelemetry
+specification. While the core API for interacting with Baggage remains the same,
+the accepted data types have changed. Baggage Keys now only allow strings (ASCII
+printable characters), and Baggage values are restricted to strings.
+
+For detailed changes, see the [changelog](../opentelemetry/CHANGELOG.md). With
+version 0.29, the Baggage API has reached "Release Candidate" status, meaning
+further breaking changes will be highly restricted.
+
+## Appender-Tracing Changes
+
+The `opentelemetry-appender-tracing` crate, which bridges `tracing` events to
+OpenTelemetry logs, has been updated to properly map `tracing` data types to the
+OpenTelemetry model. As of version 0.29, this crate is considered "Stable," and
+no further breaking changes will be made without a major version bump.
+
+## Configuration via Environment Variables
+
+The 0.29 release aligns OpenTelemetry Rust with the rest of the OpenTelemetry
+ecosystem by treating any code-based configuration as final (i.e., it cannot be
+overridden by environment variables). This policy was partially true before but
+is now applied consistently. If you prefer to configure your application via
+environment variables, avoid configuring it programmatically.
+
+## Discontinuing Dedicated Prometheus Exporter
+
+The `opentelemetry-prometheus` crate will be discontinued with the 0.29 release.
+Active development on this crate ceased a few months ago. Given that Prometheus
+now natively supports OTLP, and considering that the OpenTelemetry Rust project
+is still working towards a 1.0 release, we need to focus on essential components
+to maintain scope and ensure timely delivery.
+
+Prometheus interoperability remains a key goal for OpenTelemetry. However, the
+current `opentelemetry-prometheus` crate requires a major rewrite to eliminate
+dependencies on unmaintained crates. We may reintroduce a dedicated Prometheus
+exporter in the future once these issues are resolved.
+
+### Migration Guide
+
+For those using Prometheus as a backend, you can integrate with Prometheus using
+the following methods:
+
+1. Use the OTLP Exporter to push metrics directly to Prometheus.
+2. If you require a pull (scrape) model, push metrics to an OpenTelemetry
+   Collector using the OTLP Exporter, and configure Prometheus to scrape the
+   OpenTelemetry Collector.
+
+These alternatives ensure continued Prometheus integration while allowing us to
+focus on achieving a stable 1.0 release for OpenTelemetry Rust.
+
+## Next Release
+
+In the [next
+release](https://github.com/open-telemetry/opentelemetry-rust/milestone/21), we
+expect to stabilize the Metrics SDK and resolve the long-standing question of
+`tokio-tracing` vs. `opentelemetry tracing`, which is a prerequisite before
+stabilizing Distributed Tracing. Additionally, `Context` is also expected to be
+enhanced with the ability to suppress telemetry-induced-telemetry.
+
+## Instrumentation Libraries
+
+Unlike other OpenTelemetry language implementations, OpenTelemetry Rust historically did not
+maintain any instrumentations directly. This has recently changed with a
+[contribution](https://github.com/open-telemetry/opentelemetry-rust-contrib/pull/202)
+from one of the founding members of the OpenTelemetry Rust project to the
+contrib repository, providing an instrumentation library for
+[`actix-web`](https://github.com/open-telemetry/opentelemetry-rust-contrib/tree/main/actix-web-opentelemetry).
+We expect that this instrumentation will serve as a reference implementation demonstrating best practices for
+creating OpenTelemetry instrumentations in Rust.
+
+We welcome additional contributions of instrumentation libraries to the contrib repository.
+
+## Thanks
+
+Thank you to everyone who contributed to this milestone. Please share your feedback
+through GitHub issues or join the discussion in the OTel-Rust Slack channel
+[here](https://cloud-native.slack.com/archives/C03GDP0H023).

opentelemetry-appender-log/CHANGELOG.md

@@ -2,11 +2,17 @@
 
 ## vNext
 
+## 0.29.0
+
+Released 2025-Mar-21
+
 - Similar to the `opentelemetry-appender-tracing` fix [2658](https://github.com/open-telemetry/opentelemetry-rust/issues/2658)
   InstrumentationScope(Logger) used by the appender now uses an empty ("") named Logger.
   Previously, a Logger with name and version of the crate was used.
   Receivers (processors, exporters) are expected to use `LogRecord.target()` as scope name.
   This is already done in OTLP Exporters, so this change should be transparent to most users.
+- Update `opentelemetry` dependency version to 0.29.
+- Update `opentelemetry-semantic-conventions` dependency version to 0.29.
 
 ## 0.28.0
 

opentelemetry-appender-log/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "opentelemetry-appender-log"
-version = "0.28.0"
+version = "0.29.0"
 description = "An OpenTelemetry appender for the log crate"
 homepage = "https://github.com/open-telemetry/opentelemetry-rust/tree/main/opentelemetry-appender-log"
 repository = "https://github.com/open-telemetry/opentelemetry-rust/tree/main/opentelemetry-appender-log"
@@ -11,12 +11,12 @@ rust-version = "1.75.0"
 edition = "2021"
 
 [dependencies]
-opentelemetry = { version = "0.28", path = "../opentelemetry", features = [
+opentelemetry = { version = "0.29", path = "../opentelemetry", features = [
   "logs",
 ] }
 log = { workspace = true, features = ["kv", "std"] }
 serde = { workspace = true, optional = true, features = ["std"] }
-opentelemetry-semantic-conventions = { version = "0.28", path = "../opentelemetry-semantic-conventions", optional = true, features = [
+opentelemetry-semantic-conventions = { version = "0.29", path = "../opentelemetry-semantic-conventions", optional = true, features = [
   "semconv_experimental",
 ] }
 

opentelemetry-appender-tracing/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## vNext
 
+## 0.29.0
+
+Released 2025-Mar-21
+
 Fixes [1682](https://github.com/open-telemetry/opentelemetry-rust/issues/1682).
 "spec_unstable_logs_enabled" feature now do not suppress logs for other layers.
 
@@ -53,6 +57,7 @@ of string.
   instead of previously reporting the user provided attribute "error".
   `error!(....error = &OTelSdkError::AlreadyShutdown as &dyn std::error::Error...)`
 - perf - small perf improvement by avoiding string allocation of `target`
+- Update `opentelemetry` dependency version to 0.29.
 
 ## 0.28.1
 

opentelemetry-appender-tracing/Cargo.toml

@@ -12,12 +12,12 @@ rust-version = "1.75.0"
 
 [dependencies]
 log = { workspace = true, optional = true }
-opentelemetry = { version = "0.28", path = "../opentelemetry", features = ["logs"] }
+opentelemetry = { version = "0.29", path = "../opentelemetry", features = ["logs"] }
 tracing = { workspace = true, features = ["std"]}
 tracing-core = { workspace = true }
 tracing-log = { workspace = true, optional = true }
 tracing-subscriber = { workspace = true, features = ["registry", "std"] }
-tracing-opentelemetry = { workspace = true, optional = true }
+# tracing-opentelemetry = { workspace = true, optional = true }
 
 [dev-dependencies]
 log = { workspace = true }
@@ -36,7 +36,8 @@ pprof = { version = "0.14", features = ["flamegraph", "criterion"] }
 default = []
 experimental_metadata_attributes = ["dep:tracing-log"]
 spec_unstable_logs_enabled = ["opentelemetry/spec_unstable_logs_enabled"]
-experimental_use_tracing_span_context = ["tracing-opentelemetry"]
+# TODO - Enable this in 0.29.1 (once tracing-opentelemetry v0.30 is released)
+# experimental_use_tracing_span_context = ["tracing-opentelemetry"]
 
 
 [[bench]]

opentelemetry-appender-tracing/src/layer.rs

@@ -244,25 +244,25 @@ where
         // Visit fields.
         event.record(&mut visitor);
 
-        #[cfg(feature = "experimental_use_tracing_span_context")]
-        if let Some(span) = _ctx.event_span(event) {
-            use tracing_opentelemetry::OtelData;
-            let opt_span_id = span
-                .extensions()
-                .get::<OtelData>()
-                .and_then(|otd| otd.builder.span_id);
-
-            let opt_trace_id = span.scope().last().and_then(|root_span| {
-                root_span
-                    .extensions()
-                    .get::<OtelData>()
-                    .and_then(|otd| otd.builder.trace_id)
-            });
-
-            if let Some((trace_id, span_id)) = opt_trace_id.zip(opt_span_id) {
-                log_record.set_trace_context(trace_id, span_id, None);
-            }
-        }
+        // #[cfg(feature = "experimental_use_tracing_span_context")]
+        // if let Some(span) = _ctx.event_span(event) {
+        //     use tracing_opentelemetry::OtelData;
+        //     let opt_span_id = span
+        //         .extensions()
+        //         .get::<OtelData>()
+        //         .and_then(|otd| otd.builder.span_id);
+
+        //     let opt_trace_id = span.scope().last().and_then(|root_span| {
+        //         root_span
+        //             .extensions()
+        //             .get::<OtelData>()
+        //             .and_then(|otd| otd.builder.trace_id)
+        //     });
+
+        //     if let Some((trace_id, span_id)) = opt_trace_id.zip(opt_span_id) {
+        //         log_record.set_trace_context(trace_id, span_id, None);
+        //     }
+        // }
 
         //emit record
         self.logger.emit(log_record);
@@ -673,66 +673,66 @@ mod tests {
         }
     }
 
-    #[cfg(feature = "experimental_use_tracing_span_context")]
-    #[test]
-    fn tracing_appender_inside_tracing_crate_context() {
-        use opentelemetry_sdk::trace::InMemorySpanExporterBuilder;
+    // #[cfg(feature = "experimental_use_tracing_span_context")]
+    // #[test]
+    // fn tracing_appender_inside_tracing_crate_context() {
+    //     use opentelemetry_sdk::trace::InMemorySpanExporterBuilder;
 
-        // Arrange
-        let exporter: InMemoryLogExporter = InMemoryLogExporter::default();
-        let logger_provider = SdkLoggerProvider::builder()
-            .with_simple_exporter(exporter.clone())
-            .build();
+    //     // Arrange
+    //     let exporter: InMemoryLogExporter = InMemoryLogExporter::default();
+    //     let logger_provider = SdkLoggerProvider::builder()
+    //         .with_simple_exporter(exporter.clone())
+    //         .build();
 
-        // setup tracing layer to compare trace/span IDs against
-        let span_exporter = InMemorySpanExporterBuilder::new().build();
-        let tracer_provider = SdkTracerProvider::builder()
-            .with_simple_exporter(span_exporter.clone())
-            .build();
-        let tracer = tracer_provider.tracer("test-tracer");
+    //     // setup tracing layer to compare trace/span IDs against
+    //     let span_exporter = InMemorySpanExporterBuilder::new().build();
+    //     let tracer_provider = SdkTracerProvider::builder()
+    //         .with_simple_exporter(span_exporter.clone())
+    //         .build();
+    //     let tracer = tracer_provider.tracer("test-tracer");
 
-        let level_filter = tracing_subscriber::filter::LevelFilter::ERROR;
-        let log_layer =
-            layer::OpenTelemetryTracingBridge::new(&logger_provider).with_filter(level_filter);
+    //     let level_filter = tracing_subscriber::filter::LevelFilter::ERROR;
+    //     let log_layer =
+    //         layer::OpenTelemetryTracingBridge::new(&logger_provider).with_filter(level_filter);
 
-        let subscriber = tracing_subscriber::registry()
-            .with(log_layer)
-            .with(tracing_opentelemetry::layer().with_tracer(tracer));
+    //     let subscriber = tracing_subscriber::registry()
+    //         .with(log_layer)
+    //         .with(tracing_opentelemetry::layer().with_tracer(tracer));
 
-        // Avoiding global subscriber.init() as that does not play well with unit tests.
-        let _guard = tracing::subscriber::set_default(subscriber);
+    //     // Avoiding global subscriber.init() as that does not play well with unit tests.
+    //     let _guard = tracing::subscriber::set_default(subscriber);
 
-        // Act
-        tracing::error_span!("outer-span").in_scope(|| {
-            error!("first-event");
+    //     // Act
+    //     tracing::error_span!("outer-span").in_scope(|| {
+    //         error!("first-event");
 
-            tracing::error_span!("inner-span").in_scope(|| {
-                error!("second-event");
-            });
-        });
+    //         tracing::error_span!("inner-span").in_scope(|| {
+    //             error!("second-event");
+    //         });
+    //     });
 
-        assert!(logger_provider.force_flush().is_ok());
+    //     assert!(logger_provider.force_flush().is_ok());
 
-        let logs = exporter.get_emitted_logs().expect("No emitted logs");
-        assert_eq!(logs.len(), 2, "Expected 2 logs, got: {logs:?}");
+    //     let logs = exporter.get_emitted_logs().expect("No emitted logs");
+    //     assert_eq!(logs.len(), 2, "Expected 2 logs, got: {logs:?}");
 
-        let spans = span_exporter.get_finished_spans().unwrap();
-        assert_eq!(spans.len(), 2);
+    //     let spans = span_exporter.get_finished_spans().unwrap();
+    //     assert_eq!(spans.len(), 2);
 
-        let trace_id = spans[0].span_context.trace_id();
-        assert_eq!(trace_id, spans[1].span_context.trace_id());
-        let inner_span_id = spans[0].span_context.span_id();
-        let outer_span_id = spans[1].span_context.span_id();
-        assert_eq!(outer_span_id, spans[0].parent_span_id);
+    //     let trace_id = spans[0].span_context.trace_id();
+    //     assert_eq!(trace_id, spans[1].span_context.trace_id());
+    //     let inner_span_id = spans[0].span_context.span_id();
+    //     let outer_span_id = spans[1].span_context.span_id();
+    //     assert_eq!(outer_span_id, spans[0].parent_span_id);
 
-        let trace_ctx0 = logs[0].record.trace_context().unwrap();
-        let trace_ctx1 = logs[1].record.trace_context().unwrap();
+    //     let trace_ctx0 = logs[0].record.trace_context().unwrap();
+    //     let trace_ctx1 = logs[1].record.trace_context().unwrap();
 
-        assert_eq!(trace_ctx0.trace_id, trace_id);
-        assert_eq!(trace_ctx1.trace_id, trace_id);
-        assert_eq!(trace_ctx0.span_id, outer_span_id);
-        assert_eq!(trace_ctx1.span_id, inner_span_id);
-    }
+    //     assert_eq!(trace_ctx0.trace_id, trace_id);
+    //     assert_eq!(trace_ctx1.trace_id, trace_id);
+    //     assert_eq!(trace_ctx0.span_id, outer_span_id);
+    //     assert_eq!(trace_ctx1.span_id, inner_span_id);
+    // }
 
     #[test]
     fn tracing_appender_standalone_with_tracing_log() {

opentelemetry-http/CHANGELOG.md

@@ -2,6 +2,12 @@
 
 ## vNext
 
+## 0.29.0
+
+Released 2025-Mar-21
+
+- Update `opentelemetry` dependency version to 0.29.
+
 ## 0.28.0
 
 Released 2025-Feb-10

opentelemetry-http/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "opentelemetry-http"
-version = "0.28.0"
+version = "0.29.0"
 description = "Helper implementations for sending HTTP requests. Uses include propagating and extracting context over http, exporting telemetry, requesting sampling strategies."
 homepage = "https://github.com/open-telemetry/opentelemetry-rust/tree/main/opentelemetry-http"
 repository = "https://github.com/open-telemetry/opentelemetry-rust/tree/main/opentelemetry-http"
@@ -23,7 +23,7 @@ http = { workspace = true }
 http-body-util = { workspace = true, optional = true }
 hyper = { workspace = true, optional = true }
 hyper-util = { workspace = true, features = ["client-legacy", "http1", "http2"], optional = true }
-opentelemetry = { version = "0.28", path = "../opentelemetry", features = ["trace"] }
+opentelemetry = { version = "0.29", path = "../opentelemetry", features = ["trace"] }
 reqwest = { workspace = true, features = ["blocking"], optional = true }
 tokio = { workspace = true, features = ["time"], optional = true }
 tracing = {workspace = true, optional = true}