disable context propagation (#94)

* disable context propagation

* bump version

* removes leftover feature

* fix new test

* add back disabled test

.github/workflows/ci.yml

@@ -18,6 +18,7 @@ jobs:
           - opentelemetry_0_16
           - opentelemetry_0_17
           - opentelemetry_0_18
+          - opentelemetry_0_19
     steps:
       - name: Checkout repository
         uses: actions/checkout@v2
@@ -44,6 +45,7 @@ jobs:
           - opentelemetry_0_16
           - opentelemetry_0_17
           - opentelemetry_0_18
+          - opentelemetry_0_19
     steps:
       - name: Checkout repository
         uses: actions/checkout@v2
@@ -90,6 +92,7 @@ jobs:
           - opentelemetry_0_16
           - opentelemetry_0_17
           - opentelemetry_0_18
+          - opentelemetry_0_19
     steps:
       - name: Checkout repository
         uses: actions/checkout@v2
@@ -118,6 +121,7 @@ jobs:
           - opentelemetry_0_16
           - opentelemetry_0_17
           - opentelemetry_0_18
+          - opentelemetry_0_19
     steps:
       - name: Checkout repository
         uses: actions/checkout@v2

reqwest-tracing/CHANGELOG.md

@@ -6,6 +6,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.4.5] - 2023-06-20
+
+### Added
+- A new extension `DisableOtelPropagation` which stops opentelemetry contexts propagating
+- Support for opentelemetry 0.19
+
 ## [0.4.4] - 2023-05-15
 
 ### Added

reqwest-tracing/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "reqwest-tracing"
-version = "0.4.4"
+version = "0.4.5"
 authors = ["Rodrigo Gryzinski <rodrigo.gryzinski@truelayer.com>"]
 edition = "2018"
 description = "Opentracing middleware for reqwest."
@@ -16,6 +16,7 @@ opentelemetry_0_15 = ["opentelemetry_0_15_pkg", "tracing-opentelemetry_0_14_pkg"
 opentelemetry_0_16 = ["opentelemetry_0_16_pkg", "tracing-opentelemetry_0_16_pkg"]
 opentelemetry_0_17 = ["opentelemetry_0_17_pkg", "tracing-opentelemetry_0_17_pkg"]
 opentelemetry_0_18 = ["opentelemetry_0_18_pkg", "tracing-opentelemetry_0_18_pkg"]
+opentelemetry_0_19 = ["opentelemetry_0_19_pkg", "tracing-opentelemetry_0_19_pkg"]
 
 
 [dependencies]
@@ -34,12 +35,14 @@ opentelemetry_0_15_pkg = { package = "opentelemetry", version = "0.15.0", option
 opentelemetry_0_16_pkg = { package = "opentelemetry", version = "0.16.0", optional = true }
 opentelemetry_0_17_pkg = { package = "opentelemetry", version = "0.17.0", optional = true }
 opentelemetry_0_18_pkg = { package = "opentelemetry", version = "0.18.0", optional = true }
+opentelemetry_0_19_pkg = { package = "opentelemetry", version = "0.19.0", optional = true }
 tracing-opentelemetry_0_12_pkg = { package = "tracing-opentelemetry",version = "0.12.0", optional = true }
 tracing-opentelemetry_0_13_pkg = { package = "tracing-opentelemetry", version = "0.13.0", optional = true }
 tracing-opentelemetry_0_14_pkg = { package = "tracing-opentelemetry",version = "0.14.0", optional = true }
 tracing-opentelemetry_0_16_pkg = { package = "tracing-opentelemetry",version = "0.16.0", optional = true }
 tracing-opentelemetry_0_17_pkg = { package = "tracing-opentelemetry",version = "0.17.0", optional = true }
 tracing-opentelemetry_0_18_pkg = { package = "tracing-opentelemetry",version = "0.18.0", optional = true }
+tracing-opentelemetry_0_19_pkg = { package = "tracing-opentelemetry",version = "0.19.0", optional = true }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 getrandom = { version = "0.2.0", features = ["js"] }

reqwest-tracing/src/lib.rs

@@ -90,16 +90,17 @@ mod middleware;
     feature = "opentelemetry_0_16",
     feature = "opentelemetry_0_17",
     feature = "opentelemetry_0_18",
+    feature = "opentelemetry_0_19",
 ))]
 mod otel;
 mod reqwest_otel_span_builder;
 pub use middleware::TracingMiddleware;
 pub use reqwest_otel_span_builder::{
     default_on_request_end, default_on_request_failure, default_on_request_success,
-    default_span_name, DefaultSpanBackend, OtelName, OtelPathNames, ReqwestOtelSpanBackend,
+    default_span_name, DefaultSpanBackend, DisableOtelPropagation, OtelName, OtelPathNames,
-    SpanBackendWithUrl, ERROR_CAUSE_CHAIN, ERROR_MESSAGE, HTTP_HOST, HTTP_METHOD, HTTP_SCHEME,
+    ReqwestOtelSpanBackend, SpanBackendWithUrl, ERROR_CAUSE_CHAIN, ERROR_MESSAGE, HTTP_HOST,
-    HTTP_STATUS_CODE, HTTP_URL, HTTP_USER_AGENT, NET_HOST_PORT, OTEL_KIND, OTEL_NAME,
+    HTTP_METHOD, HTTP_SCHEME, HTTP_STATUS_CODE, HTTP_URL, HTTP_USER_AGENT, NET_HOST_PORT,
-    OTEL_STATUS_CODE,
+    OTEL_KIND, OTEL_NAME, OTEL_STATUS_CODE,
 };
 
 #[doc(hidden)]

reqwest-tracing/src/middleware.rs

@@ -45,8 +45,6 @@ where
         let request_span = ReqwestOtelSpan::on_request_start(&req, extensions);
 
         let outcome_future = async {
-            // Adds tracing headers to the given request to propagate the OpenTelemetry context to downstream revivers of the request.
-            // Spans added by downstream consumers will be part of the same trace.
             #[cfg(any(
                 feature = "opentelemetry_0_13",
                 feature = "opentelemetry_0_14",
@@ -54,8 +52,15 @@ where
                 feature = "opentelemetry_0_16",
                 feature = "opentelemetry_0_17",
                 feature = "opentelemetry_0_18",
+                feature = "opentelemetry_0_19",
             ))]
-            let req = crate::otel::inject_opentelemetry_context_into_request(req);
+            let req = if !extensions.contains::<crate::DisableOtelPropagation>() {
+                // Adds tracing headers to the given request to propagate the OpenTelemetry context to downstream revivers of the request.
+                // Spans added by downstream consumers will be part of the same trace.
+                crate::otel::inject_opentelemetry_context_into_request(req)
+            } else {
+                req
+            };
 
             // Run the request
             let outcome = next.run(req, extensions).await;

reqwest-tracing/src/otel.rs

@@ -21,6 +21,9 @@ use opentelemetry_0_17_pkg as opentelemetry;
 #[cfg(feature = "opentelemetry_0_18")]
 use opentelemetry_0_18_pkg as opentelemetry;
 
+#[cfg(feature = "opentelemetry_0_19")]
+use opentelemetry_0_19_pkg as opentelemetry;
+
 #[cfg(feature = "opentelemetry_0_13")]
 pub use tracing_opentelemetry_0_12_pkg as tracing_opentelemetry;
 
@@ -39,6 +42,9 @@ pub use tracing_opentelemetry_0_17_pkg as tracing_opentelemetry;
 #[cfg(feature = "opentelemetry_0_18")]
 pub use tracing_opentelemetry_0_18_pkg as tracing_opentelemetry;
 
+#[cfg(feature = "opentelemetry_0_19")]
+pub use tracing_opentelemetry_0_19_pkg as tracing_opentelemetry;
+
 use opentelemetry::global;
 use opentelemetry::propagation::Injector;
 use tracing_opentelemetry::OpenTelemetrySpanExt;
@@ -80,10 +86,13 @@ impl<'a> Injector for RequestCarrier<'a> {
 
 #[cfg(test)]
 mod test {
+    use std::sync::OnceLock;
+
     use super::*;
-    use crate::TracingMiddleware;
+    use crate::{DisableOtelPropagation, TracingMiddleware};
     use opentelemetry::sdk::propagation::TraceContextPropagator;
-    use reqwest_middleware::ClientBuilder;
+    use reqwest::Response;
+    use reqwest_middleware::{ClientBuilder, ClientWithMiddleware, Extension};
     use tracing::{info_span, Instrument, Level};
     #[cfg(any(
         feature = "opentelemetry_0_13",
@@ -99,17 +108,22 @@ mod test {
     use tracing_subscriber_0_3::{filter, layer::SubscriberExt, Registry};
     use wiremock::{matchers::any, Mock, MockServer, ResponseTemplate};
 
-    #[tokio::test]
+    async fn make_echo_request_in_otel_context(client: ClientWithMiddleware) -> Response {
-    async fn tracing_middleware_propagates_otel_data_even_when_the_span_is_disabled() {
+        static TELEMETRY: OnceLock<()> = OnceLock::new();
+
+        TELEMETRY.get_or_init(|| {
             let tracer = opentelemetry::sdk::export::trace::stdout::new_pipeline()
                 .with_writer(std::io::sink())
                 .install_simple();
             let telemetry = tracing_opentelemetry::layer().with_tracer(tracer);
             let subscriber = Registry::default()
-            .with(filter::Targets::new().with_target("reqwest_tracing::otel::test", Level::DEBUG))
+                .with(
+                    filter::Targets::new().with_target("reqwest_tracing::otel::test", Level::DEBUG),
+                )
                 .with(telemetry);
             tracing::subscriber::set_global_default(subscriber).unwrap();
             global::set_text_map_propagator(TraceContextPropagator::new());
+        });
 
         // Mock server - sends all request headers back in the response
         let server = MockServer::start().await;
@@ -124,17 +138,40 @@ mod test {
             .mount(&server)
             .await;
 
-        let client = ClientBuilder::new(reqwest::Client::new())
+        client
-            .with(TracingMiddleware::default())
-            .build();
-
-        let resp = client
             .get(server.uri())
             .send()
             .instrument(info_span!("some_span"))
             .await
-            .unwrap();
+            .unwrap()
+    }
 
-        assert!(resp.headers().contains_key("traceparent"));
+    #[tokio::test]
+    async fn tracing_middleware_propagates_otel_data_even_when_the_span_is_disabled() {
+        let client = ClientBuilder::new(reqwest::Client::new())
+            .with(TracingMiddleware::default())
+            .build();
+
+        let resp = make_echo_request_in_otel_context(client).await;
+
+        assert!(
+            resp.headers().contains_key("traceparent"),
+            "by default, the tracing middleware will propagate otel contexts"
+        );
+    }
+
+    #[tokio::test]
+    async fn context_no_propagated() {
+        let client = ClientBuilder::new(reqwest::Client::new())
+            .with_init(Extension(DisableOtelPropagation))
+            .with(TracingMiddleware::default())
+            .build();
+
+        let resp = make_echo_request_in_otel_context(client).await;
+
+        assert!(
+            !resp.headers().contains_key("traceparent"),
+            "request should not contain traceparent if context propagation is disabled"
+        );
     }
 }

reqwest-tracing/src/reqwest_otel_span_builder.rs

@@ -276,6 +276,41 @@ impl OtelPathNames {
     }
 }
 
+/// `DisableOtelPropagation` disables opentelemetry header propagation, while still tracing the HTTP request.
+///
+/// By default, the [`TracingMiddleware`](super::TracingMiddleware) middleware will also propagate any opentelemtry
+/// contexts to the server. For any external facing requests, this can be problematic and it should be disabled.
+///
+/// Usage:
+/// ```no_run
+/// # use reqwest_middleware::Result;
+/// use reqwest_middleware::{ClientBuilder, Extension};
+/// use reqwest_tracing::{
+///     TracingMiddleware, DisableOtelPropagation
+/// };
+/// # async fn example() -> Result<()> {
+/// let reqwest_client = reqwest::Client::builder().build().unwrap();
+/// let client = ClientBuilder::new(reqwest_client)
+///    // Inserts the extension before the request is started
+///    .with_init(Extension(DisableOtelPropagation))
+///    // Makes use of that extension to specify the otel name
+///    .with(TracingMiddleware::default())
+///    .build();
+///
+/// let resp = client.get("https://truelayer.com").send().await.unwrap();
+///
+/// // Or specify it on the individual request (will take priority)
+/// let resp = client.post("https://api.truelayer.com/payment")
+///     .with_extension(DisableOtelPropagation)
+///     .send()
+///     .await
+///     .unwrap();
+/// # Ok(())
+/// # }
+/// ```
+#[derive(Clone)]
+pub struct DisableOtelPropagation;
+
 /// Removes the username and/or password parts of the url, if present.
 fn remove_credentials(url: &Url) -> Cow<'_, str> {
     if !url.username().is_empty() || url.password().is_some() {