miden_node_utils/tracing/
grpc.rs

1use tracing::field;
2
3use crate::tracing::OpenTelemetrySpanExt;
4
5/// Returns a [`trace_fn`](tonic::transport::server::Server) implementation for gRPC requests
6/// which adds open-telemetry information to the span.
7///
8/// Creates an `info` span following the open-telemetry standard: `{service}/{method}`.
9/// The span name is dynamically set using the HTTP path via the `otel.name` field.
10/// Additionally also pulls in remote tracing context which allows the server trace to be connected
11/// to the client's origin trace.
12pub fn grpc_trace_fn<T>(request: &http::Request<T>) -> tracing::Span {
13    // A gRPC request's path ends with `../<service>/<method>`.
14    let mut path_segments = request.uri().path().rsplit('/');
15
16    let method = path_segments.next().unwrap_or_default();
17    let service = path_segments.next().unwrap_or_default();
18
19    // Create a span with a generic, static name. Fields to be recorded after needs to be
20    // initialized as empty since otherwise the assignment will have no effect.
21    let span = tracing::info_span!(
22        "rpc",
23        otel.name = field::Empty,
24        rpc.service = service,
25        rpc.method = method
26    );
27
28    // Set the span name via otel.name
29    let otel_name = format!("{service}/{method}");
30    span.record("otel.name", otel_name);
31
32    // Pull the open-telemetry parent context using the HTTP extractor
33    let otel_ctx = opentelemetry::global::get_text_map_propagator(|propagator| {
34        propagator.extract(&MetadataExtractor(&tonic::metadata::MetadataMap::from_headers(
35            request.headers().clone(),
36        )))
37    });
38    let _ = tracing_opentelemetry::OpenTelemetrySpanExt::set_parent(&span, otel_ctx);
39
40    // Adds various network attributes to the span, including remote address and port.
41    //
42    // See [server attributes](https://opentelemetry.io/docs/specs/semconv/rpc/rpc-spans/#server-attributes).
43
44    // Set HTTP attributes.
45    span.set_attribute("rpc.system", "grpc");
46    if let Some(host) = request.uri().host() {
47        span.set_attribute("server.address", host);
48    }
49    if let Some(host_port) = request.uri().port() {
50        span.set_attribute("server.port", host_port.as_u16());
51    }
52    let remote_addr = request
53        .extensions()
54        .get::<tonic::transport::server::TcpConnectInfo>()
55        .and_then(tonic::transport::server::TcpConnectInfo::remote_addr);
56    if let Some(addr) = remote_addr {
57        span.set_attribute("client.address", addr.ip());
58        span.set_attribute("client.port", addr.port());
59        span.set_attribute("network.peer.address", addr.ip());
60        span.set_attribute("network.peer.port", addr.port());
61        span.set_attribute("network.transport", "tcp");
62        match addr.ip() {
63            std::net::IpAddr::V4(_) => span.set_attribute("network.type", "ipv4"),
64            std::net::IpAddr::V6(_) => span.set_attribute("network.type", "ipv6"),
65        }
66    }
67
68    span
69}
70
71/// Injects open-telemetry remote context into traces.
72#[derive(Copy, Clone)]
73pub struct OtelInterceptor;
74
75impl tonic::service::Interceptor for OtelInterceptor {
76    fn call(
77        &mut self,
78        mut request: tonic::Request<()>,
79    ) -> Result<tonic::Request<()>, tonic::Status> {
80        use tracing_opentelemetry::OpenTelemetrySpanExt;
81        let ctx = tracing::Span::current().context();
82        opentelemetry::global::get_text_map_propagator(|propagator| {
83            propagator.inject_context(&ctx, &mut MetadataInjector(request.metadata_mut()));
84        });
85
86        Ok(request)
87    }
88}
89
90struct MetadataExtractor<'a>(&'a tonic::metadata::MetadataMap);
91impl opentelemetry::propagation::Extractor for MetadataExtractor<'_> {
92    /// Get a value for a key from the `MetadataMap`.  If the value can't be converted to &str,
93    /// returns None
94    fn get(&self, key: &str) -> Option<&str> {
95        self.0.get(key).and_then(|metadata| metadata.to_str().ok())
96    }
97
98    /// Collect all the keys from the `MetadataMap`.
99    fn keys(&self) -> Vec<&str> {
100        self.0
101            .keys()
102            .map(|key| match key {
103                tonic::metadata::KeyRef::Ascii(v) => v.as_str(),
104                tonic::metadata::KeyRef::Binary(v) => v.as_str(),
105            })
106            .collect::<Vec<_>>()
107    }
108}
109
110struct MetadataInjector<'a>(&'a mut tonic::metadata::MetadataMap);
111impl opentelemetry::propagation::Injector for MetadataInjector<'_> {
112    /// Set a key and value in the `MetadataMap`.  Does nothing if the key or value are not valid
113    /// inputs
114    fn set(&mut self, key: &str, value: String) {
115        if let Ok(key) = tonic::metadata::MetadataKey::from_bytes(key.as_bytes())
116            && let Ok(val) = tonic::metadata::MetadataValue::try_from(&value)
117        {
118            self.0.insert(key, val);
119        }
120    }
121}
miden_node_utils/tracing/grpc.rs

miden_node_utils/tracing/
grpc.rs
