Implement zipkin exporter provider (open-telemetry#4991)

exporters/zipkin/build.gradle.kts

@@ -15,6 +15,7 @@ dependencies {
 
   implementation(project(":exporters:common"))
   implementation(project(":semconv"))
+  implementation(project(":sdk-extensions:autoconfigure-spi"))
 
   implementation("io.zipkin.reporter2:zipkin-sender-okhttp3")
 

exporters/zipkin/src/main/java/io/opentelemetry/exporter/zipkin/internal/ZipkinSpanExporterProvider.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.exporter.zipkin.internal;
+
+import io.opentelemetry.exporter.zipkin.ZipkinSpanExporter;
+import io.opentelemetry.exporter.zipkin.ZipkinSpanExporterBuilder;
+import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
+import io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider;
+import io.opentelemetry.sdk.trace.export.SpanExporter;
+import java.time.Duration;
+
+/**
+ * {@link SpanExporter} SPI implementation for {@link ZipkinSpanExporter}.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+public class ZipkinSpanExporterProvider implements ConfigurableSpanExporterProvider {
+  @Override
+  public String getName() {
+    return "zipkin";
+  }
+
+  @Override
+  public SpanExporter createExporter(ConfigProperties config) {
+    ZipkinSpanExporterBuilder builder = ZipkinSpanExporter.builder();
+
+    String endpoint = config.getString("otel.exporter.zipkin.endpoint");
+    if (endpoint != null) {
+      builder.setEndpoint(endpoint);
+    }
+
+    Duration timeout = config.getDuration("otel.exporter.zipkin.timeout");
+    if (timeout != null) {
+      builder.setReadTimeout(timeout);
+    }
+
+    return builder.build();
+  }
+}

exporters/zipkin/src/main/resources/META-INF/services/io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider

@@ -0,0 +1 @@
+io.opentelemetry.exporter.zipkin.internal.ZipkinSpanExporterProvider

sdk-extensions/autoconfigure/build.gradle.kts

@@ -21,7 +21,6 @@ dependencies {
   compileOnly(project(":exporters:otlp:logs"))
   compileOnly(project(":exporters:otlp:common"))
   compileOnly(project(":exporters:prometheus"))
-  compileOnly(project(":exporters:zipkin"))
 
   annotationProcessor("com.google.auto.value:auto-value")
 

sdk-extensions/autoconfigure/src/main/java/io/opentelemetry/sdk/autoconfigure/SpanExporterConfiguration.java

@@ -19,8 +19,6 @@
 import io.opentelemetry.exporter.otlp.http.trace.OtlpHttpSpanExporterBuilder;
 import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporter;
 import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporterBuilder;
-import io.opentelemetry.exporter.zipkin.ZipkinSpanExporter;
-import io.opentelemetry.exporter.zipkin.ZipkinSpanExporterBuilder;
 import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
 import io.opentelemetry.sdk.autoconfigure.spi.ConfigurationException;
 import io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider;
@@ -41,6 +39,7 @@ final class SpanExporterConfiguration {
   static {
     EXPORTER_ARTIFACT_ID_BY_NAME = new HashMap<>();
     EXPORTER_ARTIFACT_ID_BY_NAME.put("logging", "opentelemetry-exporter-logging");
+    EXPORTER_ARTIFACT_ID_BY_NAME.put("zipkin", "opentelemetry-exporter-zipkin");
   }
 
   // Visible for testing
@@ -69,12 +68,7 @@ static Map<String, SpanExporter> configureSpanExporters(
     }
 
     NamedSpiManager<SpanExporter> spiExportersManager =
-        SpiUtil.loadConfigurable(
-            ConfigurableSpanExporterProvider.class,
-            ConfigurableSpanExporterProvider::getName,
-            ConfigurableSpanExporterProvider::createExporter,
-            config,
-            serviceClassLoader);
+        spanExporterSpiManager(config, serviceClassLoader);
 
     return exporterNames.stream()
         .collect(
@@ -86,6 +80,17 @@ static Map<String, SpanExporter> configureSpanExporters(
                         config)));
   }
 
+  // Visible for testing
+  static NamedSpiManager<SpanExporter> spanExporterSpiManager(
+      ConfigProperties config, ClassLoader serviceClassLoader) {
+    return SpiUtil.loadConfigurable(
+        ConfigurableSpanExporterProvider.class,
+        ConfigurableSpanExporterProvider::getName,
+        ConfigurableSpanExporterProvider::createExporter,
+        config,
+        serviceClassLoader);
+  }
+
   // Visible for testing
   static SpanExporter configureExporter(
       String name,
@@ -97,8 +102,6 @@ static SpanExporter configureExporter(
         return configureOtlp(config, meterProvider);
       case "jaeger":
         return configureJaeger(config, meterProvider);
-      case "zipkin":
-        return configureZipkin(config);
       case "logging-otlp":
         ClasspathUtil.checkClassExists(
             "io.opentelemetry.exporter.logging.otlp.OtlpJsonLoggingSpanExporter",
@@ -196,25 +199,5 @@ private static SpanExporter configureJaeger(
     return builder.build();
   }
 
-  private static SpanExporter configureZipkin(ConfigProperties config) {
-    ClasspathUtil.checkClassExists(
-        "io.opentelemetry.exporter.zipkin.ZipkinSpanExporter",
-        "Zipkin Exporter",
-        "opentelemetry-exporter-zipkin");
-    ZipkinSpanExporterBuilder builder = ZipkinSpanExporter.builder();
-
-    String endpoint = config.getString("otel.exporter.zipkin.endpoint");
-    if (endpoint != null) {
-      builder.setEndpoint(endpoint);
-    }
-
-    Duration timeout = config.getDuration("otel.exporter.zipkin.timeout");
-    if (timeout != null) {
-      builder.setReadTimeout(timeout);
-    }
-
-    return builder.build();
-  }
-
   private SpanExporterConfiguration() {}
 }

sdk-extensions/autoconfigure/src/test/java/io/opentelemetry/sdk/autoconfigure/NotOnClasspathTest.java

@@ -66,7 +66,8 @@ void zipkin() {
                     "zipkin", EMPTY, NamedSpiManager.createEmpty(), MeterProvider.noop()))
         .isInstanceOf(ConfigurationException.class)
         .hasMessageContaining(
-            "Zipkin Exporter enabled but opentelemetry-exporter-zipkin not found on classpath");
+            "otel.traces.exporter set to \"zipkin\" but opentelemetry-exporter-zipkin not found on classpath."
+                + " Make sure to add it as a dependency.");
   }
 
   @Test

sdk-extensions/autoconfigure/src/testFullConfig/java/io/opentelemetry/sdk/autoconfigure/SpanExporterConfigurationTest.java

@@ -12,6 +12,7 @@
 import io.opentelemetry.api.metrics.MeterProvider;
 import io.opentelemetry.exporter.jaeger.JaegerGrpcSpanExporter;
 import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporter;
+import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
 import io.opentelemetry.sdk.autoconfigure.spi.ConfigurationException;
 import io.opentelemetry.sdk.trace.export.SpanExporter;
 import java.util.Collections;
@@ -76,12 +77,15 @@ void configureJaegerTimeout() {
   // Timeout difficult to test using real exports so just check that things don't blow up.
   @Test
   void configureZipkinTimeout() {
+    ConfigProperties config =
+        DefaultConfigProperties.createForTest(
+            Collections.singletonMap("otel.exporter.zipkin.timeout", "5s"));
     SpanExporter exporter =
         SpanExporterConfiguration.configureExporter(
             "zipkin",
-            DefaultConfigProperties.createForTest(
-                Collections.singletonMap("otel.exporter.zipkin.timeout", "5s")),
-            NamedSpiManager.createEmpty(),
+            config,
+            SpanExporterConfiguration.spanExporterSpiManager(
+                config, SpanExporterConfigurationTest.class.getClassLoader()),
             MeterProvider.noop());
     try {
       assertThat(exporter).isNotNull();