Add the ability to autodetect opentracing implementations

java/client/src/org/openqa/selenium/remote/BUCK

@@ -138,6 +138,7 @@ java_library(name = 'remote-lib',
   deps = [
     ':http-session-id',
     '//java/client/src/org/openqa/selenium:selenium',
+    '//third_party/java/contrib:opentracing-tracerresolver',
     '//third_party/java/opencensus:opencensus-api',
     '//third_party/java/opentracing:opentracing-noop',
     '//third_party/java/guava:guava',

java/client/src/org/openqa/selenium/remote/tracing/DistributedTracer.java

@@ -21,6 +21,7 @@
 
 import org.openqa.selenium.BuildInfo;
 
+import io.opentracing.contrib.tracerresolver.TracerResolver;
 import io.opentracing.noop.NoopTracerFactory;
 
 import java.util.LinkedList;
@@ -31,7 +32,9 @@
  */
 public class DistributedTracer {
 
-  private static volatile DistributedTracer INSTANCE = DistributedTracer.builder().build();
+  private static volatile DistributedTracer INSTANCE = DistributedTracer.builder()
+      .registerDetectedTracers()
+      .build();
   private static final ThreadLocal<LinkedList<Span>> ACTIVE_SPANS =
       ThreadLocal.withInitial(LinkedList::new);
   private final ImmutableSet<io.opencensus.trace.Tracer> ocTracers;
@@ -125,6 +128,15 @@ private Builder() {
       register(NoopTracerFactory.create());
     }
 
+    public Builder registerDetectedTracers() {
+      io.opentracing.Tracer tracer = TracerResolver.resolveTracer();
+      if (tracer != null) {
+        register(tracer);
+      }
+
+      return this;
+    }
+
     public Builder register(io.opentracing.Tracer openTracingTracer) {
       otTracers.add(Objects.requireNonNull(openTracingTracer, "Tracer must be set."));
       return this;

third_party/java/contrib/BUCK

@@ -22,3 +22,16 @@ prebuilt_jar(
   ],
 )
 
+prebuilt_jar(
+  name = 'opentracing-tracerresolver',
+  maven_coords = 'io.opentracing.contrib:opentracing-tracerresolver:jar:0.1.5',
+  binary_jar = 'opentracing-tracerresolver-0.1.5.jar',
+  source_jar = 'opentracing-tracerresolver-0.1.5-sources.jar',
+  deps = [
+    '//third_party/java/opentracing:opentracing-api',
+    '//third_party/java/opentracing:opentracing-util'
+  ],
+  visibility = [
+    '//java/client/src/org/openqa/selenium/remote:',
+  ],
+)

third_party/java/opentracing/BUCK

@@ -4,8 +4,7 @@ prebuilt_jar(
   binary_jar = 'opentracing-api-0.31.0.jar',
   source_jar = 'opentracing-api-0.31.0-sources.jar',
   visibility = [
-    '//third_party/java/contrib:opentracing-concurrent',
-    '//third_party/java/contrib:opentracing-okhttp3',
+    '//third_party/java/contrib:',
     '//java/client/src/org/openqa/selenium/remote:',
   ],
 )
@@ -25,3 +24,16 @@ prebuilt_jar(
   ],
 )
 
+prebuilt_jar(
+  name = 'opentracing-util',
+  maven_coords = 'io.opentracing:opentracing-util:jar:0.31.0',
+  binary_jar = 'opentracing-util-0.31.0.jar',
+  source_jar = 'opentracing-util-0.31.0-sources.jar',
+  deps = [
+    ':opentracing-api',
+    ':opentracing-noop'
+  ],
+  visibility = [
+    '//third_party/java/contrib:opentracing-tracerresolver',
+  ],
+)