fix(propagator-jaeger):extract 1 digit traceFlag(0) return 1

Author: shmilyoo

packages/opentelemetry-propagator-jaeger/src/JaegerPropagator.ts

@@ -145,7 +145,7 @@ function deserializeSpanContext(serializedString: string): SpanContext | null {
 
   const traceId = _traceId.padStart(32, '0');
   const spanId = _spanId.padStart(16, '0');
-  const traceFlags = flags.match(/^[0-9a-f]{2}$/i) ? parseInt(flags) & 1 : 1;
+  const traceFlags = flags.match(/^[0-9a-f]{1,2}$/i) ? parseInt(flags) & 1 : 1;
 
   return { traceId, spanId, isRemote: true, traceFlags };
 }

packages/opentelemetry-propagator-jaeger/test/JaegerPropagator.test.ts

@@ -159,7 +159,7 @@ describe('JaegerPropagator', () => {
       });
     });
 
-    it('should extract context of a sampled span from carrier with 1 bit flag', () => {
+    it('should extract context of a sampled span from carrier with 1 bit flag(1)', () => {
       carrier[UBER_TRACE_ID_HEADER] =
         '9c41e35aeb6d1272:45fd2a9709dadcf1:a13699e3fb724f40:1';
       const extractedSpanContext = trace.getSpanContext(
@@ -174,6 +174,21 @@ describe('JaegerPropagator', () => {
       });
     });
 
+    it("should extract context of a sampled span from carrier with 1 bit flag(0)", () => {
+      carrier[UBER_TRACE_ID_HEADER] =
+        "9c41e35aeb6d1272:45fd2a9709dadcf1:a13699e3fb724f40:0";
+      const extractedSpanContext = trace.getSpanContext(
+        jaegerPropagator.extract(ROOT_CONTEXT, carrier, defaultTextMapGetter)
+      );
+
+      assert.deepStrictEqual(extractedSpanContext, {
+        spanId: "45fd2a9709dadcf1",
+        traceId: "00000000000000009c41e35aeb6d1272",
+        isRemote: true,
+        traceFlags: TraceFlags.NONE,
+      });
+    });
+
     it('should extract context of a sampled span from UTF-8 encoded carrier', () => {
       carrier[UBER_TRACE_ID_HEADER] =
         'ac1f3dc3c2c0b06e%3A5ac292c4a11a163e%3Ac086aaa825821068%3A1';