feat: Add OpenTelemetry Support

feat: Add OpenTelemetry Support
feat: Add Support for Tracing Propagation Headers

pom.xml

@@ -42,23 +42,6 @@
         </repository>
     </distributionManagement>
 
-    <developers>
-        <developer>
-            <id>henriquetruta</id>
-            <name>Henrique Truta</name>
-            <email>[email protected]</email>
-            <organization>Spotify AB</organization>
-            <organizationUrl>http://www.spotify.com</organizationUrl>
-        </developer>
-        <developer>
-            <id>hewhomustnotbenamed</id>
-            <name>Abhimanyu Shegokar</name>
-            <email>[email protected]</email>
-            <organization>Spotify AB</organization>
-            <organizationUrl>http://www.spotify.com</organizationUrl>
-        </developer>
-    </developers>
-
     <repositories>
         <repository>
             <id>apache.snapshots</id>
@@ -102,6 +85,7 @@
         <objenesis.version>3.3</objenesis.version>
         <opencensus.version>0.31.1</opencensus.version>
         <okhttp.version>4.11.0</okhttp.version>
+        <opentelemetry.version>1.42.1</opentelemetry.version>
 
         <shade.id>${project.groupId}.githubclient.shade</shade.id>
     </properties>
@@ -120,6 +104,13 @@
                 <scope>import</scope>
                 <type>pom</type>
             </dependency>
+            <dependency>
+                <groupId>io.opentelemetry</groupId>
+                <artifactId>opentelemetry-bom</artifactId>
+                <version>${opentelemetry.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
         </dependencies>
     </dependencyManagement>
 
@@ -179,6 +170,25 @@
             <artifactId>opencensus-api</artifactId>
             <version>${opencensus.version}</version>
         </dependency>
+
+        <dependency>
+            <groupId>io.opentelemetry</groupId>
+            <artifactId>opentelemetry-api</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.opentelemetry</groupId>
+            <artifactId>opentelemetry-sdk</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.opentelemetry</groupId>
+            <artifactId>opentelemetry-sdk-testing</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>commons-io</groupId>
+            <artifactId>commons-io</artifactId>
+            <version>2.7</version>
+            <scope>compile</scope>
+        </dependency>
         <dependency>
             <groupId>io.jsonwebtoken</groupId>
             <artifactId>jjwt-impl</artifactId>
@@ -246,12 +256,6 @@
             <version>${okhttp.version}</version>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>commons-io</groupId>
-            <artifactId>commons-io</artifactId>
-            <version>2.7</version>
-            <scope>compile</scope>
-        </dependency>
     </dependencies>
 
     <profiles>

src/main/java/com/spotify/github/tracing/BaseTracer.java

@@ -0,0 +1,60 @@
+/*-
+ * -\-\-
+ * github-client
+ * --
+ * Copyright (C) 2016 - 2021 Spotify AB
+ * --
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * -/-/-
+ */
+
+package com.spotify.github.tracing;
+
+import okhttp3.Request;
+
+import java.util.concurrent.CompletionStage;
+
+public abstract class BaseTracer implements Tracer {
+    @Override
+    public Span span(final String name, final String method, final CompletionStage<?> future) {
+        return internalSpan(name, method, future);
+    }
+
+    @Override
+    public Span span(final String path, final String method) {
+        return internalSpan(path, method, null);
+    }
+
+    @Override
+    public Span span(final Request request) {
+        return internalSpan(request.url().toString(), request.method(), null);
+    }
+
+    protected abstract Span internalSpan(
+            String path,
+            String method,
+            CompletionStage<?> future);
+
+    @Override
+    public void attachSpanToFuture(final Span span, final CompletionStage<?> future) {
+        future.whenComplete(
+                (result, t) -> {
+                    if (t == null) {
+                        span.success();
+                    } else {
+                        span.failure(t);
+                    }
+                    span.close();
+                });
+    }
+}

src/main/java/com/spotify/github/Span.java → src/main/java/com/spotify/github/tracing/Span.java

@@ -18,7 +18,9 @@
  * -/-/-
  */
 
-package com.spotify.github;
+package com.spotify.github.tracing;
+
+import okhttp3.Request;
 
 public interface Span extends AutoCloseable {
 
@@ -29,5 +31,7 @@ public interface Span extends AutoCloseable {
     /** Close span. Must be called for any opened span. */
     @Override
     void close();
+
+    Request decorateRequest(Request request);
 }
 

src/main/java/com/spotify/github/tracing/TraceHelper.java

@@ -0,0 +1,33 @@
+/*-
+ * -\-\-
+ * github-api
+ * --
+ * Copyright (C) 2021 Spotify AB
+ * --
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * -/-/-
+ */
+
+package com.spotify.github.tracing;
+
+public class TraceHelper {
+    // Tracing Headers
+    public static final String HEADER_CLOUD_TRACE_CONTEXT = "X-Cloud-Trace-Context";
+    public static final String HEADER_TRACE_PARENT = "traceparent";
+    public static final String HEADER_TRACE_STATE = "tracestate";
+
+    // Private constructor to prevent instantiation
+    private TraceHelper() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/com/spotify/github/Tracer.java → src/main/java/com/spotify/github/tracing/Tracer.java

@@ -7,9 +7,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -18,15 +18,26 @@
  * -/-/-
  */
 
-package com.spotify.github;
+package com.spotify.github.tracing;
+
+import okhttp3.Request;
 
 import java.util.concurrent.CompletionStage;
 
 public interface Tracer {
 
-    /** Create scoped span. Span will be closed when future completes. */
+    /**
+     * Create scoped span. Span will be closed when future completes.
+     */
     Span span(
             String path, String method, CompletionStage<?> future);
 
+    Span span(
+            String path, String method);
+
+    Span span(
+            Request request);
+
+    void attachSpanToFuture(Span span, CompletionStage<?> future);
 }
 

src/main/java/com/spotify/github/opencensus/OpenCensusSpan.java → src/main/java/com/spotify/github/tracing/opencensus/OpenCensusSpan.java

@@ -7,9 +7,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -18,20 +18,24 @@
  * -/-/-
  */
 
-package com.spotify.github.opencensus;
+package com.spotify.github.tracing.opencensus;
+
 import static java.util.Objects.requireNonNull;
-import com.spotify.github.Span;
+
+import com.spotify.github.tracing.Span;
+import com.spotify.github.tracing.TraceHelper;
 import com.spotify.github.v3.exceptions.RequestNotOkException;
 import io.opencensus.trace.AttributeValue;
 import io.opencensus.trace.Status;
+import okhttp3.Request;
 
-class OpenCensusSpan implements Span {
+public class OpenCensusSpan implements Span {
 
     public static final int NOT_FOUND = 404;
     public static final int INTERNAL_SERVER_ERROR = 500;
     private final io.opencensus.trace.Span span;
 
-    OpenCensusSpan(final io.opencensus.trace.Span span) {
+    public OpenCensusSpan(final io.opencensus.trace.Span span) {
         this.span = requireNonNull(span);
     }
 
@@ -59,5 +63,14 @@ public Span failure(final Throwable t) {
     public void close() {
         span.end();
     }
+
+    @Override
+    public Request decorateRequest(final Request request) {
+        return request.newBuilder()
+                .header(TraceHelper.HEADER_CLOUD_TRACE_CONTEXT, span.getContext().getTraceId().toString())
+                .header(TraceHelper.HEADER_TRACE_PARENT, span.getContext().getTraceId().toString())
+                .header(TraceHelper.HEADER_TRACE_STATE, span.getContext().getTracestate().toString())
+                .build();
+    }
 }
 

src/main/java/com/spotify/github/opencensus/OpenCensusTracer.java → src/main/java/com/spotify/github/tracing/opencensus/OpenCensusTracer.java

@@ -7,9 +7,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -18,10 +18,10 @@
  * -/-/-
  */
 
-package com.spotify.github.opencensus;
+package com.spotify.github.tracing.opencensus;
 
-import com.spotify.github.Span;
-import com.spotify.github.Tracer;
+import com.spotify.github.tracing.BaseTracer;
+import com.spotify.github.tracing.Span;
 import io.opencensus.trace.Tracing;
 
 import java.util.concurrent.CompletionStage;
@@ -30,22 +30,16 @@
 import static io.opencensus.trace.Span.Kind.CLIENT;
 import static java.util.Objects.requireNonNull;
 
-public class OpenCensusTracer implements Tracer {
+public class OpenCensusTracer extends BaseTracer {
 
     private static final io.opencensus.trace.Tracer TRACER = Tracing.getTracer();
 
-    @Override
-    public Span span(final String name, final String method, final CompletionStage<?> future) {
-        return internalSpan(name, method, future);
-    }
-
     @SuppressWarnings("MustBeClosedChecker")
-    private Span internalSpan(
+    protected Span internalSpan(
             final String path,
             final String method,
             final CompletionStage<?> future) {
         requireNonNull(path);
-        requireNonNull(future);
 
         final io.opencensus.trace.Span ocSpan =
                 TRACER.spanBuilder("GitHub Request").setSpanKind(CLIENT).startSpan();
@@ -56,15 +50,9 @@ private Span internalSpan(
         ocSpan.putAttribute("method", stringAttributeValue(method));
         final Span span = new OpenCensusSpan(ocSpan);
 
-        future.whenComplete(
-                (result, t) -> {
-                    if (t == null) {
-                        span.success();
-                    } else {
-                        span.failure(t);
-                    }
-                    span.close();
-                });
+        if (future != null) {
+            attachSpanToFuture(span, future);
+        }
 
         return span;
     }