"Add tracehandler test"

Author: cindy-peng

google-cloud-logging/src/main/java/com/google/cloud/logging/Context.java

@@ -37,6 +37,9 @@ public class Context {
   private static final Pattern W3C_TRACE_CONTEXT_FORMAT =
       Pattern.compile(
           "^00-(?!00000000000000000000000000000000)[0-9a-f]{32}-(?!0000000000000000)[0-9a-f]{16}-[0-9a-f]{2}$");
+  // Trace sampled flag for bit masking
+  // see https://www.w3.org/TR/trace-context/#trace-flags for details
+  private static final byte FLAG_SAMPLED = 1; // 00000001
   private final HttpRequest request;
   private final String traceId;
   private final String spanId;
@@ -144,7 +147,9 @@ public Builder setTraceSampled(boolean traceSampled) {
     @CanIgnoreReturnValue
     public Builder loadCloudTraceContext(String cloudTrace) {
       if (cloudTrace != null) {
+        String traceSampledString = Iterables.get(Splitter.on(";o=").split(cloudTrace), 1);
         cloudTrace = Iterables.get(Splitter.on(';').split(cloudTrace), 0);
+
         int split = cloudTrace.indexOf('/');
         if (split >= 0) {
           String traceId = cloudTrace.substring(0, split);
@@ -155,6 +160,10 @@ public Builder loadCloudTraceContext(String cloudTrace) {
             if (!spanId.isEmpty()) {
               setSpanId(spanId);
             }
+            // do not set trace sampled flag without trace Id
+            if (!traceSampledString.isEmpty()) {
+              setTraceSampled(traceSampledString.equals("1"));
+            }
           }
         } else if (!cloudTrace.isEmpty()) {
           setTraceId(cloudTrace);
@@ -186,7 +195,9 @@ public Builder loadW3CTraceParentContext(String traceParent) {
         List<String> fields = Splitter.on('-').splitToList(traceParent);
         setTraceId(fields.get(1));
         setSpanId(fields.get(2));
-        // fields[3] contains flag(s)
+        boolean sampled = (Integer.parseInt(fields.get(3), 16) & FLAG_SAMPLED) == FLAG_SAMPLED;
+        System.out.println("trace: " + fields.get(1) + ", span: " + fields.get(2) + ", sampled string " + fields.get(3) + ", sampled boolean: " + sampled);
+        setTraceSampled(sampled);
       }
       return this;
     }

google-cloud-logging/src/main/java/com/google/cloud/logging/LoggingHandler.java

@@ -171,7 +171,7 @@ public enum LogTarget {
 
   private final WriteOption[] defaultWriteOptions;
 
-  /** Creates an handler that publishes messages to Cloud Logging. */
+  /** Creates a handler that publishes messages to Cloud Logging. */
   public LoggingHandler() {
     this(null, null, null);
   }

google-cloud-logging/src/test/java/com/google/cloud/logging/ContextTest.java

@@ -37,6 +37,7 @@ public class ContextTest {
   // DO NOT use dash in trace and span id because W3C traceparent format uses dash as a delimieter
   private static final String TEST_TRACE_ID = "test_trace_id";
   private static final String TEST_SPAN_ID = "test_span_id";
+  private static final boolean TEST_TRACE_SAMPLED = true;
 
   private static final HttpRequest REQUEST =
       HttpRequest.newBuilder()
@@ -68,6 +69,7 @@ public class ContextTest {
           .setRequest(PARTIAL_REQUEST)
           .setTraceId(TEST_TRACE_ID)
           .setSpanId(TEST_SPAN_ID)
+          .setTraceSampled(TEST_TRACE_SAMPLED)
           .build();
 
   @Test
@@ -87,6 +89,7 @@ public void testCompareContexts() {
             .setServerIp(SERVER_IP)
             .setTraceId(TEST_TRACE_ID)
             .setSpanId(TEST_SPAN_ID)
+            .setTraceSampled(TEST_TRACE_SAMPLED)
             .build();
 
     assertNotEquals(TEST_CONTEXT, context1);
@@ -103,9 +106,11 @@ public void testContextBuilder() {
     assertEquals(PARTIAL_REQUEST, TEST_CONTEXT.getHttpRequest());
     assertEquals(TEST_TRACE_ID, TEST_CONTEXT.getTraceId());
     assertEquals(TEST_SPAN_ID, TEST_CONTEXT.getSpanId());
+    assertEquals(TEST_TRACE_SAMPLED, TEST_CONTEXT.getTraceSampled());
     assertNull(emptyContext.getHttpRequest());
     assertNull(emptyContext.getTraceId());
     assertNull(emptyContext.getSpanId());
+    assertFalse(emptyContext.getTraceSampled());
     assertEquals(TEST_CONTEXT, anotherContext);
   }
 
@@ -114,40 +119,47 @@ public void testParsingCloudTraceContext() {
     final String X_CLOUD_TRACE_NO_TRACE = "/SPAN_ID;o=TRACE_TRUE";
     final String X_CLOUD_TRACE_ONLY = TEST_TRACE_ID;
     final String X_CLOUD_TRACE_WITH_SPAN = TEST_TRACE_ID + "/" + TEST_SPAN_ID;
-    final String X_CLOUD_TRACE_FULL = TEST_TRACE_ID + "/" + TEST_SPAN_ID + ";o=TRACE_TRUE";
+    final String X_CLOUD_TRACE_FULL = TEST_TRACE_ID + "/" + TEST_SPAN_ID + ";o=" + TEST_TRACE_SAMPLED;
 
     Context.Builder builder = Context.newBuilder();
 
     builder.loadCloudTraceContext(null);
-    assertTraceAndSpan(builder.build(), null, null);
+    assertTraceSpanAndSampled(builder.build(), null, null, false);
     builder.loadCloudTraceContext("");
-    assertTraceAndSpan(builder.build(), null, null);
+    assertTraceSpanAndSampled(builder.build(), null, null, false);
     builder.loadCloudTraceContext(X_CLOUD_TRACE_NO_TRACE);
-    assertTraceAndSpan(builder.build(), null, null);
+    assertTraceSpanAndSampled(builder.build(), null, null, false);
     builder.loadCloudTraceContext(X_CLOUD_TRACE_ONLY);
-    assertTraceAndSpan(builder.build(), TEST_TRACE_ID, null);
+    assertTraceSpanAndSampled(builder.build(), TEST_TRACE_ID, null, false);
     builder.loadCloudTraceContext(X_CLOUD_TRACE_WITH_SPAN);
-    assertTraceAndSpan(builder.build(), TEST_TRACE_ID, TEST_SPAN_ID);
+    assertTraceSpanAndSampled(builder.build(), TEST_TRACE_ID, TEST_SPAN_ID, false);
     builder.loadCloudTraceContext(X_CLOUD_TRACE_FULL);
-    assertTraceAndSpan(builder.build(), TEST_TRACE_ID, TEST_SPAN_ID);
+    assertTraceSpanAndSampled(builder.build(), TEST_TRACE_ID, TEST_SPAN_ID, TEST_TRACE_SAMPLED);
   }
 
   @Test
   public void testParsingW3CTraceParent() {
     final String W3C_TEST_TRACE_ID = "12345678901234567890123456789012";
     final String W3C_TEST_SPAN_ID = "1234567890123456";
-    final String W3C_TRACE_CONTEXT = "00-" + W3C_TEST_TRACE_ID + "-" + W3C_TEST_SPAN_ID + "-00";
+    final String W3C_TEST_TRACE_SAMPLED = "0f";
+    final String W3C_TRACE_CONTEXT = "00-" + W3C_TEST_TRACE_ID + "-" + W3C_TEST_SPAN_ID + "-" + W3C_TEST_TRACE_SAMPLED;
 
     Context.Builder builder = Context.newBuilder();
 
     builder.loadW3CTraceParentContext(null);
-    assertTraceAndSpan(builder.build(), null, null);
+    assertTraceSpanAndSampled(builder.build(), null, null, false);
     builder.loadW3CTraceParentContext(W3C_TRACE_CONTEXT);
-    assertTraceAndSpan(builder.build(), W3C_TEST_TRACE_ID, W3C_TEST_SPAN_ID);
+    assertTraceSpanAndSampled(builder.build(), W3C_TEST_TRACE_ID, W3C_TEST_SPAN_ID, true);
   }
 
-  private void assertTraceAndSpan(Context context, String expectedTraceId, String expectedSpanId) {
+  private void assertTraceAndSpan1(Context context, String expectedTraceId, String expectedSpanId) {
     assertEquals(expectedTraceId, context.getTraceId());
     assertEquals(expectedSpanId, context.getSpanId());
   }
+
+  private void assertTraceSpanAndSampled(Context context, String expectedTraceId, String expectedSpanId, boolean expectedTraceSampled) {
+    assertEquals(expectedTraceId, context.getTraceId());
+    assertEquals(expectedSpanId, context.getSpanId());
+    assertEquals(expectedTraceSampled, context.getTraceSampled());
+  }
 }