feat: harden community production foundation through story 1.5

crates/crank-trace/src/lib.rs

@@ -6,7 +6,50 @@
 
 use std::future::Future;
 
+use opentelemetry::{
+    Context,
+    trace::{SpanContext, SpanId, TraceContextExt, TraceFlags, TraceId, TraceState},
+};
 use tracing::{Instrument, Span, field::Empty, info_span};
+use tracing_opentelemetry::OpenTelemetrySpanExt;
+
+pub fn set_parent_from_trace_context(span: &Span, context: &crank_core::TraceContext) -> bool {
+    let mut parts = context.traceparent().split('-');
+    let (Some("00"), Some(trace_id), Some(parent_id), Some(flags), None) = (
+        parts.next(),
+        parts.next(),
+        parts.next(),
+        parts.next(),
+        parts.next(),
+    ) else {
+        return false;
+    };
+    let (Ok(trace_id), Ok(parent_id)) = (TraceId::from_hex(trace_id), SpanId::from_hex(parent_id))
+    else {
+        return false;
+    };
+    let flags = match flags {
+        "00" => TraceFlags::default(),
+        "01" => TraceFlags::SAMPLED,
+        _ => return false,
+    };
+    let parent = SpanContext::new(trace_id, parent_id, flags, true, TraceState::default());
+    span.set_parent(Context::new().with_remote_span_context(parent))
+        .is_ok()
+}
+
+pub fn trace_context_for_span(span: &Span) -> Option<crank_core::TraceContext> {
+    let context = span.context();
+    let span_context = context.span().span_context().clone();
+    span_context.is_valid().then(|| {
+        crank_core::TraceContext::from_span_parts(
+            &span_context.trace_id().to_string(),
+            &span_context.span_id().to_string(),
+            span_context.is_sampled(),
+        )
+        .ok()
+    })?
+}
 
 macro_rules! stage_span {
     ($name:literal) => {