Publish harness and TUI open-source

initial sync from the monorepo

crates/common/xai-tracing/src/http_client.rs

@@ -0,0 +1,155 @@
+use async_trait::async_trait;
+use opentelemetry::global;
+use opentelemetry_http::HeaderInjector;
+use reqwest::header::HeaderMap;
+use reqwest_middleware::{ClientBuilder, ClientWithMiddleware, Middleware};
+use tracing::{Instrument, Span, field};
+use tracing_opentelemetry::OpenTelemetrySpanExt;
+
+pub fn attach_trace_to_http_request(headers: &mut HeaderMap) {
+    global::get_text_map_propagator(|propagator| {
+        let context = Span::current().context();
+        propagator.inject_context(&context, &mut HeaderInjector(headers));
+    });
+}
+
+pub type TracedHttpClient = ClientWithMiddleware;
+
+pub fn traced_client(client: reqwest::Client) -> TracedHttpClient {
+    ClientBuilder::new(client).with(TracingMiddleware).build()
+}
+
+pub fn traced_client_new() -> TracedHttpClient {
+    traced_client(reqwest::Client::new())
+}
+
+pub fn traced_client_from_builder(
+    builder: reqwest::ClientBuilder,
+) -> Result<TracedHttpClient, reqwest::Error> {
+    Ok(traced_client(builder.build()?))
+}
+
+#[derive(Clone, Debug, Default)]
+struct TracingMiddleware;
+
+#[async_trait]
+impl Middleware for TracingMiddleware {
+    async fn handle(
+        &self,
+        mut req: reqwest::Request,
+        extensions: &mut http::Extensions,
+        next: reqwest_middleware::Next<'_>,
+    ) -> reqwest_middleware::Result<reqwest::Response> {
+        let method = req.method().as_str().to_owned();
+        let url = req.url().clone();
+        // No active dispatcher → the span has no consumer and would only be
+        // downgraded to `log` spam. See `crate::dispatcher_active`.
+        let span = if crate::dispatcher_active() {
+            tracing::info_span!(
+                "http_request",
+                otel.kind = "client",
+                "http.request.method" = %method,
+                "url.full" = %url,
+                "http.response.status_code" = field::Empty,
+            )
+        } else {
+            Span::none()
+        };
+
+        let result = async move {
+            attach_trace_to_http_request(req.headers_mut());
+            next.run(req, extensions).await
+        }
+        .instrument(span.clone())
+        .await;
+
+        if let Ok(ref response) = result {
+            span.record("http.response.status_code", response.status().as_u16());
+        }
+        result
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::testing::{OtelTestEnv, otel_span_id_hex, otel_trace_id_hex, parse_traceparent};
+    use tracing::Instrument;
+    use wiremock::matchers::method;
+    use wiremock::{Mock, MockServer, ResponseTemplate};
+
+    #[tokio::test]
+    async fn attach_trace_to_http_request_writes_traceparent() {
+        let _env = OtelTestEnv::install();
+        let span = tracing::info_span!("http_request", otel.kind = "client");
+        let span_id = otel_span_id_hex(&span);
+        let mut headers = HeaderMap::new();
+        let _enter = span.enter();
+        attach_trace_to_http_request(&mut headers);
+        let tp = headers.get("traceparent").unwrap().to_str().unwrap();
+        let (_ver, _tid, injected_span_id) = parse_traceparent(tp);
+        assert_eq!(injected_span_id, span_id);
+    }
+
+    #[tokio::test]
+    async fn traced_client_injects_client_span_not_parent_on_wire() {
+        let _env = OtelTestEnv::install();
+        let server = MockServer::start().await;
+        Mock::given(method("GET"))
+            .respond_with(ResponseTemplate::new(200))
+            .mount(&server)
+            .await;
+
+        let client = traced_client(reqwest::Client::new());
+        let parent = tracing::info_span!("parent_handler");
+        let parent_span_id = otel_span_id_hex(&parent);
+        let parent_trace_id = otel_trace_id_hex(&parent);
+
+        async {
+            client
+                .get(format!("{}/health", server.uri()))
+                .send()
+                .await
+                .unwrap();
+        }
+        .instrument(parent)
+        .await;
+
+        let received = server.received_requests().await.unwrap();
+        assert_eq!(received.len(), 1);
+        let tp = received[0]
+            .headers
+            .get("traceparent")
+            .expect("traceparent on wire")
+            .to_str()
+            .unwrap();
+        let (_ver, injected_trace_id, injected_span_id) = parse_traceparent(tp);
+
+        assert_eq!(injected_trace_id, parent_trace_id);
+        assert_ne!(injected_span_id, parent_span_id);
+    }
+
+    #[tokio::test]
+    async fn traced_client_returns_response_status() {
+        let _env = OtelTestEnv::install();
+        let server = MockServer::start().await;
+        Mock::given(method("GET"))
+            .respond_with(ResponseTemplate::new(404))
+            .mount(&server)
+            .await;
+
+        let client = traced_client_new();
+        let resp = client
+            .get(format!("{}/missing", server.uri()))
+            .send()
+            .await
+            .unwrap();
+        assert_eq!(resp.status().as_u16(), 404);
+        assert!(
+            server.received_requests().await.unwrap()[0]
+                .headers
+                .get("traceparent")
+                .is_some()
+        );
+    }
+}