Fix: traceparent variable issue

src/main/java/io/jenkins/plugins/opentelemetry/job/OtelEnvironmentContributor.java

@@ -11,6 +11,7 @@
 import hudson.model.EnvironmentContributor;
 import hudson.model.Run;
 import hudson.model.TaskListener;
+import io.opentelemetry.api.trace.Span;
 import javax.inject.Inject;
 
 /**
@@ -25,7 +26,12 @@ public class OtelEnvironmentContributor extends EnvironmentContributor {
 
     @Override
     public void buildEnvironmentFor(@NonNull Run run, @NonNull EnvVars envs, @NonNull TaskListener listener) {
-        otelEnvironmentContributorService.addEnvironmentVariables(run, envs, otelTraceService.getSpan(run));
+        Span span = Span.current();
+        // If there is no active span on the thread, it falls back to the run's root span
+        if (!span.getSpanContext().isValid()) {
+            span = otelTraceService.getSpan(run);
+        }
+        otelEnvironmentContributorService.addEnvironmentVariables(run, envs, span);
     }
 
     @Inject

src/test/java/io/jenkins/plugins/opentelemetry/job/TraceParentPipelineTest.java

@@ -0,0 +1,100 @@
+package io.jenkins.plugins.opentelemetry.job;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertNotNull;
+
+import hudson.model.Result;
+import io.jenkins.plugins.opentelemetry.JenkinsOpenTelemetryPluginConfiguration;
+import jenkins.model.GlobalConfiguration;
+import org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition;
+import org.jenkinsci.plugins.workflow.job.WorkflowJob;
+import org.jenkinsci.plugins.workflow.job.WorkflowRun;
+import org.junit.Rule;
+import org.junit.Test;
+import org.jvnet.hudson.test.JenkinsRule;
+
+public class TraceParentPipelineTest {
+
+    @Rule
+    public JenkinsRule jenkinsRule = new JenkinsRule();
+
+    @Test
+    public void TraceParentPropagation() throws Exception {
+        JenkinsOpenTelemetryPluginConfiguration config =
+                GlobalConfiguration.all().get(JenkinsOpenTelemetryPluginConfiguration.class);
+
+        assertNotNull(config);
+
+        config.setEndpoint("http://localhost:4317");
+        config.setExportOtelConfigurationAsEnvironmentVariables(true);
+        config.save();
+
+        WorkflowJob job = jenkinsRule.createProject(WorkflowJob.class, "traceparent-withenv-trycatch-test");
+
+        String pipelineScript = "node {\n" + "  stage('Stage-A') {\n"
+                + "    sh 'echo a_tp=$TRACEPARENT'\n"
+                + "  }\n"
+                + "\n"
+                + "  withEnv(['FOO=bar']) {\n"
+                + "    stage('Stage-B') {\n"
+                + "      sh 'echo b_tp=$TRACEPARENT'\n"
+                + "      try {\n"
+                + "        sh 'echo try_tp=$TRACEPARENT'\n"
+                + "        sh 'exit 1'\n"
+                + "      } catch (err) {\n"
+                + "        sh 'echo catch_tp=$TRACEPARENT'\n"
+                + "      } finally {\n"
+                + "        sh 'echo final_tp=$TRACEPARENT'\n"
+                + "      }\n"
+                + "    }\n"
+                + "  }\n"
+                + "}";
+
+        job.setDefinition(new CpsFlowDefinition(pipelineScript, true));
+
+        WorkflowRun run = jenkinsRule.assertBuildStatus(Result.SUCCESS, job.scheduleBuild2(0));
+
+        String logs = JenkinsRule.getLog(run);
+
+        String aTp = extract("a_tp=", logs);
+        String bTp = extract("b_tp=", logs);
+        String tryTp = extract("try_tp=", logs);
+        String catchTp = extract("catch_tp=", logs);
+        String finalTp = extract("final_tp=", logs);
+
+        assertNotNull(aTp);
+        assertNotNull(bTp);
+        assertNotNull(tryTp);
+        assertNotNull(catchTp);
+        assertNotNull(finalTp);
+
+        assertNotEquals(aTp, bTp);
+        assertNotEquals(bTp, tryTp);
+        assertNotEquals(bTp, catchTp);
+        assertNotEquals(bTp, finalTp);
+        assertNotEquals(tryTp, catchTp);
+        assertNotEquals(tryTp, finalTp);
+
+        String traceId = traceId(aTp);
+
+        assertEquals(traceId, traceId(bTp));
+        assertEquals(traceId, traceId(tryTp));
+        assertEquals(traceId, traceId(catchTp));
+        assertEquals(traceId, traceId(finalTp));
+    }
+
+    private String extract(String prefix, String log) {
+        for (String line : log.split("\n")) {
+            if (line.contains(prefix)) {
+                return line.substring(line.indexOf(prefix) + prefix.length()).trim();
+            }
+        }
+        return null;
+    }
+
+    private String traceId(String traceParent) {
+        String[] parts = traceParent.split("-");
+        return parts.length >= 2 ? parts[1] : null;
+    }
+}