Sanitize query parameters in url.full telemetry

sdk/core/azure_core/CHANGELOG.md

@@ -17,6 +17,8 @@
 
 ### Other Changes
 
+- The `url.full` span attribute in distributed traces now has query parameter values sanitized. Only parameters in `LoggingOptions::additional_allowed_query_params` and the default allow list (e.g., `api-version`) retain their values; all others are replaced with `REDACTED`.
+
 ## 0.33.0 (2026-03-05)
 
 ### Features Added

sdk/core/azure_core/src/http/options/instrumentation.rs

@@ -4,6 +4,13 @@
 use std::sync::Arc;
 
 /// Policy options to enable distributed tracing.
+///
+/// # Notes
+///
+/// [`LoggingOptions::additional_allowed_query_params`](super::LoggingOptions::additional_allowed_query_params)
+/// is used to sanitize query parameters in traced URLs as well.
+/// Query parameters not in the default or additional allow list will have their values
+/// replaced with `REDACTED` in the `url.full` span attribute.
 #[derive(Clone, Debug, Default)]
 pub struct InstrumentationOptions {
     /// Set the tracer provider for distributed tracing.

sdk/core/azure_core/src/http/options/mod.rs

@@ -5,8 +5,8 @@ mod instrumentation;
 mod user_agent;
 
 pub use instrumentation::*;
-use std::sync::Arc;
-use typespec_client_core::http::policies::Policy;
+use std::{borrow::Cow, collections::HashSet, sync::Arc};
+use typespec_client_core::http::{policies::Policy, DEFAULT_ALLOWED_QUERY_PARAMETERS};
 pub use typespec_client_core::http::{
     ClientMethodOptions, ExponentialRetryOptions, FixedRetryOptions, LoggingOptions,
     PipelineOptions, RetryOptions, Transport,
@@ -51,6 +51,7 @@ pub struct ClientOptions {
 pub(crate) struct CoreClientOptions {
     pub(crate) user_agent: UserAgentOptions,
     pub(crate) instrumentation: InstrumentationOptions,
+    pub(crate) allowed_query_params: HashSet<Cow<'static, str>>,
 }
 
 impl ClientOptions {
@@ -60,6 +61,12 @@ impl ClientOptions {
     pub(in crate::http) fn deconstruct(
         self,
     ) -> (CoreClientOptions, typespec_client_core::http::ClientOptions) {
+        // Merge the default allowed query parameters with any additional ones from logging options.
+        // This merged set is shared by both the logging policy and the request instrumentation policy
+        // to sanitize query parameters in logs and traced URLs.
+        let mut allowed_query_params = (*DEFAULT_ALLOWED_QUERY_PARAMETERS).clone();
+        allowed_query_params.extend(self.logging.additional_allowed_query_params.iter().cloned());
+
         let options = typespec_client_core::http::ClientOptions {
             per_call_policies: self.per_call_policies,
             per_try_policies: self.per_try_policies,
@@ -72,6 +79,7 @@ impl ClientOptions {
             CoreClientOptions {
                 user_agent: self.user_agent,
                 instrumentation: self.instrumentation,
+                allowed_query_params,
             },
             options,
         )

sdk/core/azure_core/src/http/pipeline.rs

@@ -165,8 +165,10 @@ impl Pipeline {
 
         let mut per_try_policies = per_try_policies.clone();
         if let Some(ref tracer) = tracer {
-            let request_instrumentation_policy =
-                RequestInstrumentationPolicy::new(Some(tracer.clone()));
+            let request_instrumentation_policy = RequestInstrumentationPolicy::new(
+                Some(tracer.clone()),
+                core_client_options.allowed_query_params.clone(),
+            );
             push_unique(&mut per_try_policies, request_instrumentation_policy);
         }
 

sdk/core/azure_core/src/http/policies/instrumentation/public_api_instrumentation.rs

@@ -246,6 +246,7 @@ mod tests {
     };
     use futures::future::BoxFuture;
     use std::sync::Arc;
+    use typespec_client_core::http::DEFAULT_ALLOWED_QUERY_PARAMETERS;
 
     // Test just the public API instrumentation policy without request instrumentation.
     async fn run_public_api_instrumentation_test<C>(
@@ -320,8 +321,10 @@ mod tests {
         let transport =
             TransportPolicy::new(Transport::new(Arc::new(MockHttpClient::new(callback))));
 
-        let request_instrumentation_policy =
-            RequestInstrumentationPolicy::new(Some(mock_tracer.clone()));
+        let request_instrumentation_policy = RequestInstrumentationPolicy::new(
+            Some(mock_tracer.clone()),
+            (*DEFAULT_ALLOWED_QUERY_PARAMETERS).clone(),
+        );
 
         let next: Vec<Arc<dyn Policy>> = vec![
             Arc::new(request_instrumentation_policy),