Add OTLP/HTTP collector

README.md

@@ -5,11 +5,11 @@
 # zipkin-otel
 Shared libraries that provide Zipkin integration with the OpenTelemetry. Requires JRE 11 or later.
 
-# Usage
+## Usage
 These components integrate traced applications and servers with OpenTelemetry protocols
 via interfaces defined by [Zipkin](https://github.com/openzipkin/zipkin).
 
-## Collectors
+### Collectors
 The component in a zipkin server that receives trace data is called a
 collector. A collector decodes spans reported by applications and
 persists them to a configured collector component.

collector-http/README.md

@@ -1,5 +1,3 @@
-# zipkin-collector-otel-http
+# collector-http
 
-This component implements
-the [OTLP/HTTP protocol](https://opentelemetry.io/docs/specs/otlp/#otlphttp)
-with [Armeria](https://armeria.dev/).
+This component implements the [OTLP/HTTP protocol](https://opentelemetry.io/docs/specs/otlp/#otlphttp) with [Armeria](https://armeria.dev/).

collector-http/pom.xml

@@ -6,8 +6,8 @@
 
 -->
 <project xmlns="http://maven.apache.org/POM/4.0.0"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
 
   <parent>
@@ -17,8 +17,8 @@
     <relativePath>../pom.xml</relativePath>
   </parent>
 
-  <artifactId>zipkin-collector-otel-http</artifactId>
-  <name>Zipkin Collector: OpenTelemetry HTTP</name>
+  <artifactId>collector-http</artifactId>
+  <name>Zipkin Collector: OTLP HTTP</name>
 
   <properties>
     <main.basedir>${project.basedir}/..</main.basedir>
@@ -37,6 +37,29 @@
       <version>${armeria.version}</version>
     </dependency>
 
+    <dependency>
+      <groupId>io.opentelemetry</groupId>
+      <artifactId>opentelemetry-api</artifactId>
+      <version>${opentelemetry.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>io.opentelemetry.proto</groupId>
+      <artifactId>opentelemetry-proto</artifactId>
+      <version>${opentelemetry-proto.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>io.opentelemetry.semconv</groupId>
+      <artifactId>opentelemetry-semconv</artifactId>
+      <version>${opentelemetry-semconv.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.google.protobuf</groupId>
+      <artifactId>protobuf-java</artifactId>
+      <version>${protobuf.version}</version>
+      <!-- We use provided scope to avoid pinning a protobuf version -->
+      <scope>provided</scope>
+    </dependency>
+
     <dependency>
       <groupId>${zipkin.groupId}</groupId>
       <artifactId>zipkin-tests</artifactId>
@@ -50,5 +73,24 @@
       <version>${armeria.version}</version>
       <scope>test</scope>
     </dependency>
+
+    <dependency>
+      <groupId>io.opentelemetry</groupId>
+      <artifactId>opentelemetry-sdk</artifactId>
+      <version>${opentelemetry.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>io.opentelemetry</groupId>
+      <artifactId>opentelemetry-exporter-otlp</artifactId>
+      <version>${opentelemetry.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.awaitility</groupId>
+      <artifactId>awaitility</artifactId>
+      <version>${awaitility.version}</version>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 </project>

collector-http/src/main/java/zipkin2/collector/otel/http/OpenTelemetryHttpCollector.java

@@ -4,12 +4,29 @@
  */
 package zipkin2.collector.otel.http;
 
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import com.google.protobuf.UnsafeByteOperations;
+import com.linecorp.armeria.common.AggregationOptions;
+import com.linecorp.armeria.common.HttpData;
 import com.linecorp.armeria.common.HttpRequest;
 import com.linecorp.armeria.common.HttpResponse;
+import com.linecorp.armeria.common.HttpStatus;
+import com.linecorp.armeria.common.ResponseHeaders;
+import com.linecorp.armeria.common.encoding.StreamDecoderFactory;
 import com.linecorp.armeria.server.AbstractHttpService;
 import com.linecorp.armeria.server.ServerBuilder;
 import com.linecorp.armeria.server.ServerConfigurator;
 import com.linecorp.armeria.server.ServiceRequestContext;
+import com.linecorp.armeria.server.encoding.DecodingService;
+import io.opentelemetry.proto.collector.trace.v1.ExportTraceServiceRequest;
+import zipkin2.Callback;
+import zipkin2.Span;
 import zipkin2.collector.Collector;
 import zipkin2.collector.CollectorComponent;
 import zipkin2.collector.CollectorMetrics;
@@ -18,32 +35,40 @@
 
 public final class OpenTelemetryHttpCollector extends CollectorComponent
     implements ServerConfigurator {
+
   public static Builder newBuilder() {
     return new Builder();
   }
 
   public static final class Builder extends CollectorComponent.Builder {
 
     Collector.Builder delegate = Collector.newBuilder(OpenTelemetryHttpCollector.class);
+
     CollectorMetrics metrics = CollectorMetrics.NOOP_METRICS;
 
-    @Override public Builder storage(StorageComponent storageComponent) {
+    @Override
+    public Builder storage(StorageComponent storageComponent) {
       delegate.storage(storageComponent);
       return this;
     }
 
-    @Override public Builder metrics(CollectorMetrics metrics) {
-      if (metrics == null) throw new NullPointerException("metrics == null");
+    @Override
+    public Builder metrics(CollectorMetrics metrics) {
+      if (metrics == null) {
+        throw new NullPointerException("metrics == null");
+      }
       delegate.metrics(this.metrics = metrics.forTransport("otel/http"));
       return this;
     }
 
-    @Override public Builder sampler(CollectorSampler sampler) {
+    @Override
+    public Builder sampler(CollectorSampler sampler) {
       delegate.sampler(sampler);
       return this;
     }
 
-    @Override public OpenTelemetryHttpCollector build() {
+    @Override
+    public OpenTelemetryHttpCollector build() {
       return new OpenTelemetryHttpCollector(this);
     }
 
@@ -52,38 +77,87 @@ public static final class Builder extends CollectorComponent.Builder {
   }
 
   final Collector collector;
+
   final CollectorMetrics metrics;
 
   OpenTelemetryHttpCollector(Builder builder) {
     collector = builder.delegate.build();
     metrics = builder.metrics;
   }
 
-  @Override public OpenTelemetryHttpCollector start() {
+  @Override
+  public OpenTelemetryHttpCollector start() {
     return this;
   }
 
-  @Override public String toString() {
+  @Override
+  public String toString() {
     return "OpenTelemetryHttpCollector{}";
   }
 
   /**
    * Reconfigures the service per https://opentelemetry.io/docs/specs/otlp/#otlphttp-request
    */
-  @Override public void reconfigure(ServerBuilder sb) {
+  @Override
+  public void reconfigure(ServerBuilder sb) {
+    sb.decorator(DecodingService.newDecorator(StreamDecoderFactory.gzip()));
     sb.service("/v1/traces", new HttpService(this));
   }
 
   static final class HttpService extends AbstractHttpService {
+    private static final Logger LOG = Logger.getLogger(HttpService.class.getName());
+
     final OpenTelemetryHttpCollector collector;
 
     HttpService(OpenTelemetryHttpCollector collector) {
       this.collector = collector;
     }
 
-    @Override protected HttpResponse doPost(ServiceRequestContext ctx, HttpRequest req)
-        throws Exception {
-      throw new RuntimeException("Implement me!");
+    @Override
+    protected HttpResponse doPost(ServiceRequestContext ctx, HttpRequest req) {
+      CompletableCallback result = new CompletableCallback();
+      req.aggregate(AggregationOptions.usePooledObjects(ctx.alloc(), ctx.eventLoop()
+      )).handle((msg, t) -> {
+        if (t != null) {
+          result.onError(t);
+          return null;
+        }
+        try (HttpData content = msg.content()) {
+          if (content.isEmpty()) {
+            result.onSuccess(null);
+            return null;
+          }
+
+          try {
+            ExportTraceServiceRequest request = ExportTraceServiceRequest.parseFrom(UnsafeByteOperations.unsafeWrap(content.byteBuf().nioBuffer()).newCodedInput());
+            List<Span> spans = SpanTranslator.translate(request);
+            collector.collector.accept(spans, result);
+          }
+          catch (IOException e) {
+            LOG.log(Level.WARNING, "Unable to parse the request:", e);
+            result.onError(new UncheckedIOException(e));
+          }
+          return null;
+        }
+      });
+      return HttpResponse.of(result);
+    }
+  }
+
+  static final class CompletableCallback extends CompletableFuture<HttpResponse>
+      implements Callback<Void> {
+
+    static final ResponseHeaders ACCEPTED_RESPONSE = ResponseHeaders.of(HttpStatus.ACCEPTED);
+
+    @Override
+    public void onSuccess(Void value) {
+      complete(HttpResponse.of(ACCEPTED_RESPONSE));
+    }
+
+    @Override
+    public void onError(Throwable t) {
+      completeExceptionally(t);
     }
   }
+
 }

collector-http/src/main/java/zipkin2/collector/otel/http/ProtoUtils.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright The OpenZipkin Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package zipkin2.collector.otel.http;
+
+import java.util.List;
+
+import com.google.protobuf.TextFormat;
+import io.opentelemetry.proto.common.v1.AnyValue;
+import io.opentelemetry.proto.common.v1.KeyValue;
+
+import static java.util.stream.Collectors.joining;
+
+final class ProtoUtils {
+  static String kvListToJson(List<KeyValue> attributes) {
+    return attributes.stream()
+        .map(entry -> "\"" + entry.getKey() + "\":" + valueToJson(entry.getValue()))
+        .collect(joining(",", "{", "}"));
+  }
+
+  static String valueToString(AnyValue value) {
+    if (value.hasStringValue()) {
+      return value.getStringValue();
+    }
+    return valueToJson(value);
+  }
+
+  static String valueToJson(AnyValue value) {
+    if (value.hasStringValue()) {
+      return "\"" + value.getStringValue() + "\"";
+    }
+    if (value.hasArrayValue()) {
+      // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/common/README.md#attribute
+      return value.getArrayValue().getValuesList().stream()
+          .map(ProtoUtils::valueToJson)
+          .collect(joining(",", "[", "]"));
+    }
+    if (value.hasKvlistValue()) {
+      return kvListToJson(value.getKvlistValue().getValuesList());
+    }
+    if (value.hasBoolValue()) {
+      return String.valueOf(value.getBoolValue());
+    }
+    if (value.hasDoubleValue()) {
+      return String.valueOf(value.getDoubleValue());
+    }
+    if (value.hasIntValue()) {
+      return String.valueOf(value.getIntValue());
+    }
+    if (value.hasBytesValue()) {
+      // TODO
+      return TextFormat.escapeBytes(value.getBytesValue());
+    }
+    return value.toString();
+  }
+}