address comments

Signed-off-by: TJ Zhang <[email protected]>

Author: tjzhang-BQ

ffi/src/lib.rs

@@ -1469,8 +1469,14 @@ pub struct OpenTelemetryMetricsConfig {
     pub endpoint: *const c_char,
 }
 
+/// Initializes OpenTelemetry with the given configuration.
+///
+/// # Safety
+/// * `open_telemetry_config` and its underlying traces and metrics pointers must be valid until the function returns.
 #[unsafe(no_mangle)]
-pub extern "C" fn init_open_telemetry(open_telemetry_config: OpenTelemetryConfig) -> *const c_char {
+pub unsafe extern "C" fn init_open_telemetry(
+    open_telemetry_config: OpenTelemetryConfig,
+) -> *const c_char {
     // At least one of traces or metrics must be provided
     if !open_telemetry_config.has_traces && !open_telemetry_config.has_metrics {
         let error_msg =
@@ -1540,21 +1546,29 @@ pub extern "C" fn init_open_telemetry(open_telemetry_config: OpenTelemetryConfig
     config = config.with_flush_interval(std::time::Duration::from_millis(flush_interval_ms as u64));
 
     // Initialize OpenTelemetry synchronously
-    match ensure_tokio_runtime().block_on(async { GlideOpenTelemetry::initialise(config.build()) })
-    {
-        Ok(_) => std::ptr::null(), // Success
-        Err(e) => {
-            let error_msg = format!("Failed to initialize OpenTelemetry: {}", e);
-            CString::new(error_msg)
-                .unwrap_or_else(|_| CString::new("Unknown error occurred").unwrap())
-                .into_raw()
+    match ensure_tokio_runtime() {
+        Ok(runtime) => {
+            match runtime.block_on(async { GlideOpenTelemetry::initialise(config.build()) }) {
+                Ok(_) => std::ptr::null(), // Success
+                Err(e) => {
+                    let error_msg = format!("Failed to initialize OpenTelemetry: {}", e);
+                    CString::new(error_msg)
+                        .unwrap_or_else(|_| CString::new("Unknown error occurred").unwrap())
+                        .into_raw()
+                }
+            }
         }
+        Err(e) => CString::new(e)
+            .unwrap_or_else(|_| CString::new("Unknown error occurred").unwrap())
+            .into_raw(),
     }
 }
 
-fn ensure_tokio_runtime() -> &'static Runtime {
+fn ensure_tokio_runtime() -> Result<&'static Runtime, String> {
     static TOKIO: OnceLock<Runtime> = OnceLock::new();
-    TOKIO.get_or_init(|| Runtime::new().expect("Failed to create Tokio runtime"))
+    Ok(TOKIO.get_or_init(|| {
+        Runtime::new().unwrap_or_else(|err| panic!("Failed to create Tokio runtime: {}", err))
+    }))
 }
 
 /// This function converts a raw pointer to a GlideSpan into a safe Rust reference.

go/Makefile

@@ -168,7 +168,7 @@ long-timeout-test: export TEST_FILTER = -skip "TestGlideTestSuite/TestModule|Ope
 long-timeout-test: __it
 
 # opentelemetry tests - run subtask with the opentelemetry flag enabled
-opentelemetry-test: export TEST_FILTER = -skip TestGlideTestSuite/TestModule -otel-test $(if $(test-filter), -testify.m $(test-filter))
+opentelemetry-test: export TEST_FILTER = -skip TestGlideTestSuite -otel-test -testify.m TestOpenTelemetry
 opentelemetry-test: __it
 
 __it:

go/opentelemetry.go

@@ -12,6 +12,7 @@ import "C"
 import (
 	"crypto/rand"
 	"fmt"
+	"log"
 	"math/big"
 	"unsafe"
 )
@@ -133,8 +134,13 @@ func (o *OpenTelemetry) GetSamplePercentage() int32 {
 // Uses the configured sample percentage to randomly decide whether to create a span for this request.
 func (o *OpenTelemetry) ShouldSample() bool {
 	percentage := o.GetSamplePercentage()
+	if !o.IsInitialized() || percentage <= 0 {
+		return false
+	}
+
 	currentRandom, err := rand.Int(rand.Reader, big.NewInt(100))
 	if err != nil {
+		log.Printf("Not sampling otel span due to failure to generate random number: %v", err)
 		return false
 	}
 	return o.IsInitialized() && percentage > 0 && float32(currentRandom.Int64()) < float32(percentage)