feat(otel): add support for opentelemetry @0.15 (#26)

* feat(otel): add support for opentelemetry @0.15

* add otel_15 to macro

* Add missing docs and readme entry for OTEL 0.15

Cargo.toml

@@ -22,6 +22,7 @@ categories = ["asynchronous", "web-programming"]
 default = ["opentelemetry_0_14", "emit_event_on_error"]
 opentelemetry_0_13 = ["opentelemetry_0_13_pkg", "tracing-opentelemetry_0_12_pkg"]
 opentelemetry_0_14 = ["opentelemetry_0_14_pkg", "tracing-opentelemetry_0_13_pkg"]
+opentelemetry_0_15 = ["opentelemetry_0_15_pkg", "tracing-opentelemetry_0_14_pkg"]
 emit_event_on_error = []
 
 [dependencies]
@@ -32,8 +33,10 @@ futures = "0.3.5"
 uuid = { version = "0.8.1", features = ["v4"] }
 opentelemetry_0_13_pkg = { package = "opentelemetry", version = "0.13", optional = true }
 opentelemetry_0_14_pkg = { package = "opentelemetry", version = "0.14", optional = true }
+opentelemetry_0_15_pkg = { package = "opentelemetry", version = "0.15", optional = true }
 tracing-opentelemetry_0_12_pkg = { package = "tracing-opentelemetry",version = "0.12", optional = true }
 tracing-opentelemetry_0_13_pkg = { package = "tracing-opentelemetry", version = "0.13", optional = true }
+tracing-opentelemetry_0_14_pkg = { package = "tracing-opentelemetry",version = "0.14", optional = true }
 
 [dev-dependencies]
 tracing-subscriber = { version = "0.2.12", features = ["registry", "env-filter"] }

README.md

@@ -44,6 +44,7 @@ actix-web = "4.0.0-beta.7"
 
 - `opentelemetry_0_13`: attach [OpenTelemetry](https://github.com/open-telemetry/opentelemetry-rust)'s context to the root span using OTEL 0.13.
 - `opentelemetry_0_14`: same as above but using OTEL 0.14 (enabled by default).
+- `opentelemetry_0_15`: same as above but using OTEL 0.15
 - `emit_event_on_error`: emit a [`tracing`] event when request processing fails with an error (enabled by default).
 
 `tracing-actix-web` will release `0.4.0`, going out of beta, as soon as `actix-web` releases a stable `4.0.0`.

src/lib.rs

@@ -17,6 +17,7 @@
 //!
 //! - `opentelemetry_0_13`: attach [OpenTelemetry](https://github.com/open-telemetry/opentelemetry-rust)'s context to the root span using OTEL 0.13;
 //! - `opentelemetry_0_14`: same as above but using OTEL 0.14 (enabled by default);
+//! - `opentelemetry_0_15`: same as above but using OTEL 0.15
 //! - `emit_event_on_error`: emit a [`tracing`] event when request processing fails with an error (enabled by default).
 //!
 //! `tracing-actix-web` will release `0.4.0`, going out of beta, as soon as `actix-web` releases a stable `4.0.0`.
@@ -214,7 +215,7 @@
 //!
 //! `tracing-actix-web` follows [OpenTelemetry's semantic convention](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/overview.md#spancontext)
 //! for field names.  
-//! Furthermore, if you have not disabled the `opentelemetry_0_13` or `opentelemetry_0_14` feature flags, `tracing-actix-web` automatically
+//! Furthermore, if you have not disabled the `opentelemetry_0_13` or `opentelemetry_0_14` or `opentelemetry_0_15` feature flags, `tracing-actix-web` automatically
 //! performs trace propagation according to the OpenTelemetry standard.
 //! It tries to extract the OpenTelemetry context out of the headers of incoming requests and, when it finds one, it sets
 //! it as the remote context for the current root span.
@@ -248,3 +249,6 @@ mod otel_0_13;
 
 #[cfg(feature = "opentelemetry_0_14")]
 mod otel_0_14;
+
+#[cfg(feature = "opentelemetry_0_15")]
+mod otel_0_15;

src/otel_0_15.rs

@@ -0,0 +1,36 @@
+use actix_web::dev::ServiceRequest;
+use opentelemetry_0_15_pkg::propagation::Extractor;
+
+pub(crate) struct RequestHeaderCarrier<'a> {
+    headers: &'a actix_web::http::HeaderMap,
+}
+
+impl<'a> RequestHeaderCarrier<'a> {
+    pub(crate) fn new(headers: &'a actix_web::http::HeaderMap) -> Self {
+        RequestHeaderCarrier { headers }
+    }
+}
+
+impl<'a> Extractor for RequestHeaderCarrier<'a> {
+    fn get(&self, key: &str) -> Option<&str> {
+        self.headers.get(key).and_then(|v| v.to_str().ok())
+    }
+
+    fn keys(&self) -> Vec<&str> {
+        self.headers.keys().map(|header| header.as_str()).collect()
+    }
+}
+
+pub(crate) fn set_otel_parent(req: &ServiceRequest, span: &tracing::Span) {
+    use opentelemetry_0_15_pkg::trace::TraceContextExt as _;
+    use tracing_opentelemetry_0_14_pkg::OpenTelemetrySpanExt as _;
+
+    let parent_context = opentelemetry_0_15_pkg::global::get_text_map_propagator(|propagator| {
+        propagator.extract(&crate::otel_0_15::RequestHeaderCarrier::new(req.headers()))
+    });
+    span.set_parent(parent_context);
+    // If we have a remote parent span, this will be the parent's trace identifier.
+    // If not, it will be the newly generated trace identifier with this request as root span.
+    let trace_id = span.context().span().span_context().trace_id().to_hex();
+    span.record("trace_id", &tracing::field::display(trace_id));
+}

src/root_span_macro.rs

@@ -103,6 +103,9 @@ macro_rules! root_span {
             #[cfg(feature = "opentelemetry_0_14")]
             $crate::root_span_macro::private::set_otel_parent_0_14(&$request, &span);
 
+            #[cfg(feature = "opentelemetry_0_15")]
+            $crate::root_span_macro::private::set_otel_parent_0_15(&$request, &span);
+
             span
         }
     };
@@ -133,6 +136,12 @@ pub mod private {
         crate::otel_0_14::set_otel_parent(req, span);
     }
 
+    #[cfg(feature = "opentelemetry_0_15")]
+    #[doc(hidden)]
+    pub fn set_otel_parent_0_15(req: &ServiceRequest, span: &tracing::Span) {
+        crate::otel_0_15::set_otel_parent(req, span);
+    }
+
     #[doc(hidden)]
     #[inline]
     pub fn http_method_str(method: &Method) -> Cow<'static, str> {