Initial implementation of a TracerResolver for Jaeger

build.gradle

@@ -15,6 +15,7 @@ ext.jerseyVersion = '2.22.2'
 ext.slf4jVersion = '1.7.16'
 ext.apacheHttpComponentsVersion = '4.1.2'
 ext.gsonVersion = '2.8.0'
+ext.tracerResolverVersion = '0.1.0'
 
 ext.junitVersion = '4.12'
 ext.mockitoVersion = '2.2.28'

jaeger-core/src/main/java/com/uber/jaeger/reporters/RemoteReporter.java

@@ -75,6 +75,10 @@ public void run() {
         flushInterval);
   }
 
+  public int getMaxQueueSize() {
+    return maxQueueSize;
+  }
+
   @Override
   public void report(Span span) {
     // Its better to drop spans, than to block here

jaeger-tracerresolver/README.md

@@ -0,0 +1,35 @@
+# Jaeger Tracer Resolver
+
+This module provides a Jaeger implementation for the [TracerResolver](https://github.com/opentracing-contrib/java-tracerresolver). This mechanism provides a vendor neutral approach for obtaining a `Tracer` using the JDK
+`ServiceLoader`.
+
+
+## Maven Dependency
+```xml
+<dependency>
+    <groupId>com.uber.jaeger</groupId>
+    <artifactId>jaeger-tracerresolver</artifactId>
+    <version>$jaegerVersion</version>
+</dependency>
+```
+
+## Usage
+
+```java
+Tracer tracer = TracerResolver.resolveTracer();
+```
+
+## Configuration Options
+
+The following configuration properties can be provided either as an environment variable or system property.
+The system property will override an environment variable for the same property name.
+
+Property | Default | Description
+--- | --- | ---
+JAEGER_SERVICE_NAME | _none_ | The service name (must be defined)
+JAEGER_AGENT_UDP_MAX_PACKET_SIZE | 65000 | The maximum packet size when communicating with the agent via UDP
+JAEGER_AGENT_UDP_HOST | localhost | The hostname for communicating with agent via UDP
+JAEGER_AGENT_UDP_PORT | 6831 | The port for communicating with agent via UDP
+JAEGER_REPORTER_MAX_QUEUE_SIZE | 1000 | The reporter's maximum queue size
+JAEGER_REPORTER_FLUSH_INTERVAL | 500 | The reporter's flush interval (ms)
+

jaeger-tracerresolver/build.gradle

@@ -0,0 +1,17 @@
+description = 'TracerResolver implementation for Jaeger Tracer'
+
+dependencies {
+    compile project(':jaeger-core')
+    compile group: 'io.opentracing.contrib', name: 'opentracing-tracerresolver', version: tracerResolverVersion
+
+    testCompile group: 'junit', name: 'junit', version: junitVersion
+
+    signature 'org.codehaus.mojo.signature:java16:1.1@signature'
+}
+
+jar {
+    from sourceSets.main.output
+    manifest {
+        attributes('Implementation-Title': 'jaeger-tracerresolver', 'Implementation-Version': project.version)
+    }
+}

jaeger-tracerresolver/src/main/java/com/uber/jaeger/tracerresolver/JaegerTracerResolver.java

@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2017, Uber Technologies, Inc
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.uber.jaeger.tracerresolver;
+
+import com.uber.jaeger.Tracer;
+import com.uber.jaeger.metrics.Metrics;
+import com.uber.jaeger.metrics.NullStatsReporter;
+import com.uber.jaeger.reporters.RemoteReporter;
+import com.uber.jaeger.reporters.Reporter;
+import com.uber.jaeger.samplers.ConstSampler;
+import com.uber.jaeger.samplers.Sampler;
+import com.uber.jaeger.senders.Sender;
+import com.uber.jaeger.senders.UdpSender;
+
+import io.opentracing.contrib.tracerresolver.TracerResolver;
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+public class JaegerTracerResolver extends TracerResolver {
+
+  /**
+   * Prefix for all properties used to configure the {@link TracerResolver}.
+   */
+  public static final String JAEGER_PREFIX = "JAEGER_";
+
+  /**
+   * The UDP maximum packet size used when communicating with the agent.
+   */
+  public static final String JAEGER_AGENT_UDP_MAX_PACKET_SIZE = JAEGER_PREFIX + "AGENT_UDP_MAX_PACKET_SIZE";
+
+  /**
+   * The UDP port used to locate the agent.
+   */
+  public static final String JAEGER_AGENT_UDP_PORT = JAEGER_PREFIX + "AGENT_UDP_PORT";
+
+  /**
+   * The UDP host used to locate the agent.
+   */
+  public static final String JAEGER_AGENT_UDP_HOST = JAEGER_PREFIX + "AGENT_UDP_HOST";
+
+  /**
+   * The maximum queue size for use when reporting spans remotely.
+   */
+  public static final String JAEGER_REPORTER_MAX_QUEUE_SIZE = JAEGER_PREFIX + "REPORTER_MAX_QUEUE_SIZE";
+
+  /**
+   * The flush interval when reporting spans remotely.
+   */
+  public static final String JAEGER_REPORTER_FLUSH_INTERVAL = JAEGER_PREFIX + "REPORTER_FLUSH_INTERVAL";
+
+  /**
+   * The service name.
+   */
+  public static final String JAEGER_SERVICE_NAME = JAEGER_PREFIX + "SERVICE_NAME";
+
+  static final int DEFAULT_REPORTER_FLUSH_INTERVAL = 500;
+  static final int DEFAULT_REPORTER_MAX_QUEUE_SIZE = 1000;
+
+  @Override
+  protected io.opentracing.Tracer resolve() {
+    String serviceName = getProperty(JAEGER_SERVICE_NAME);
+
+    return new Tracer.Builder(serviceName, getReporter(), getSampler()).build();
+  }
+
+  protected static Reporter getReporter() {
+    return new RemoteReporter(getSender(),
+        getPropertyAsInt(JAEGER_REPORTER_FLUSH_INTERVAL, DEFAULT_REPORTER_FLUSH_INTERVAL),
+        getPropertyAsInt(JAEGER_REPORTER_MAX_QUEUE_SIZE, DEFAULT_REPORTER_MAX_QUEUE_SIZE),
+        getMetrics());
+  }
+
+  protected static Sender getSender() {
+    return new UdpSender(getProperty(JAEGER_AGENT_UDP_HOST),
+        getPropertyAsInt(JAEGER_AGENT_UDP_PORT, 0),
+        getPropertyAsInt(JAEGER_AGENT_UDP_MAX_PACKET_SIZE, 0));
+  }
+
+  protected static Metrics getMetrics() {
+    // TODO: Support other stats reporters
+    return Metrics.fromStatsReporter(new NullStatsReporter());
+  }
+
+  protected static Sampler getSampler() {
+    // TODO: Support other samplers
+    return new ConstSampler(true);
+  }
+
+  private static String getProperty(String name) {
+    return System.getProperty(name, System.getenv(name));
+  }
+
+  private static int getPropertyAsInt(String name, int def) {
+    String value = getProperty(name);
+    if (value != null) {
+      try {
+        return Integer.parseInt(value);
+      } catch (NumberFormatException e) {
+        log.error("Failed to parse integer for property '" + name + "' with value '" + value + "'", e);
+      }
+    }
+    return def;
+  }
+
+}

jaeger-tracerresolver/src/main/resources/META-INF/services/io.opentracing.contrib.tracerresolver.TracerResolver

@@ -0,0 +1 @@
+com.uber.jaeger.tracerresolver.JaegerTracerResolver

jaeger-tracerresolver/src/test/java/com/uber/jaeger/tracerresolver/JaegerTracerResolverTest.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2017, Uber Technologies, Inc
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.uber.jaeger.tracerresolver;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import com.uber.jaeger.reporters.RemoteReporter;
+import com.uber.jaeger.reporters.Reporter;
+import com.uber.jaeger.samplers.ConstSampler;
+import com.uber.jaeger.senders.UdpSender;
+
+import io.opentracing.Tracer;
+import io.opentracing.contrib.tracerresolver.TracerResolver;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class JaegerTracerResolverTest {
+
+  @Before
+  public void clearProperties() {
+    // Explicitly clear all TracerResolver properties
+    System.clearProperty(JaegerTracerResolver.JAEGER_AGENT_UDP_HOST);
+    System.clearProperty(JaegerTracerResolver.JAEGER_AGENT_UDP_MAX_PACKET_SIZE);
+    System.clearProperty(JaegerTracerResolver.JAEGER_AGENT_UDP_PORT);
+    System.clearProperty(JaegerTracerResolver.JAEGER_REPORTER_FLUSH_INTERVAL);
+    System.clearProperty(JaegerTracerResolver.JAEGER_REPORTER_MAX_QUEUE_SIZE);
+    System.clearProperty(JaegerTracerResolver.JAEGER_SERVICE_NAME);
+  }
+
+  @Test
+  public void testResolveTracerNoServiceName() {
+    assertNull(TracerResolver.resolveTracer());
+  }
+
+  @Test
+  public void testResolveTracerDefault() {
+    System.setProperty(JaegerTracerResolver.JAEGER_SERVICE_NAME, "MyService");
+    Tracer tracer = TracerResolver.resolveTracer();
+    assertNotNull(tracer);
+    assertTrue(tracer instanceof com.uber.jaeger.Tracer);
+  }
+
+  @Test
+  public void testSamplerConst() {
+    assertTrue(JaegerTracerResolver.getSampler() instanceof ConstSampler);
+  }
+
+  @Test
+  public void testSender() {
+    assertTrue(JaegerTracerResolver.getSender() instanceof UdpSender);
+  }
+
+  @Test
+  public void testMetrics() {
+    assertNotNull(JaegerTracerResolver.getMetrics());
+  }
+
+  @Test
+  public void testReporter() {
+    System.setProperty(JaegerTracerResolver.JAEGER_REPORTER_MAX_QUEUE_SIZE, "10");
+    Reporter reporter = JaegerTracerResolver.getReporter();
+    assertTrue(reporter instanceof RemoteReporter);
+    assertEquals(10, ((RemoteReporter)reporter).getMaxQueueSize());
+  }
+
+  @Test
+  public void testReporterInvalidQueueSize() {
+    System.setProperty(JaegerTracerResolver.JAEGER_REPORTER_MAX_QUEUE_SIZE, "X");
+    Reporter reporter = JaegerTracerResolver.getReporter();
+    assertTrue(reporter instanceof RemoteReporter);
+    assertEquals(JaegerTracerResolver.DEFAULT_REPORTER_MAX_QUEUE_SIZE, ((RemoteReporter)reporter).getMaxQueueSize());
+  }
+
+}

settings.gradle

@@ -8,3 +8,4 @@ include 'jaeger-zipkin'
 include 'jaeger-crossdock'
 include 'jaeger-thrift'
 include 'jaeger-apachehttpclient'
+include 'jaeger-tracerresolver'