add spring starter span logging

instrumentation/spring/spring-boot-autoconfigure/src/main/java/io/opentelemetry/instrumentation/spring/autoconfigure/internal/instrumentation/logging/LoggingExporterAutoConfiguration.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.spring.autoconfigure.internal.instrumentation.logging;
+
+import static java.util.Collections.emptyList;
+
+import io.opentelemetry.exporter.logging.LoggingSpanExporter;
+import io.opentelemetry.instrumentation.spring.autoconfigure.internal.SdkEnabled;
+import io.opentelemetry.sdk.autoconfigure.spi.AutoConfigurationCustomizerProvider;
+import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
+import io.opentelemetry.sdk.trace.SdkTracerProviderBuilder;
+import io.opentelemetry.sdk.trace.export.SimpleSpanProcessor;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Conditional;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * This class is internal and is hence not for public use. Its APIs are unstable and can change at
+ * any time.
+ */
+@Conditional(SdkEnabled.class)
+// to match "otel.javaagent.debug" system property
+@ConditionalOnProperty(name = "otel.spring-starter.debug", havingValue = "true")
+@ConditionalOnClass(LoggingSpanExporter.class)
+@Configuration
+public class LoggingExporterAutoConfiguration {
+
+  @Bean
+  public AutoConfigurationCustomizerProvider loggingOtelCustomizer() {
+    return p ->
+        p.addTracerProviderCustomizer(
+            (builder, config) -> {
+              enableLoggingExporter(builder, config);
+              return builder;
+            });
+  }
+
+  public static void enableLoggingExporter(
+      SdkTracerProviderBuilder builder, ConfigProperties config) {
+    // don't install another instance if the user has already explicitly requested it.
+    if (loggingExporterIsNotAlreadyConfigured(config)) {
+      builder.addSpanProcessor(SimpleSpanProcessor.create(LoggingSpanExporter.create()));
+    }
+  }
+
+  private static boolean loggingExporterIsNotAlreadyConfigured(ConfigProperties config) {
+    return !config.getList("otel.traces.exporter", emptyList()).contains("logging");
+  }
+}

instrumentation/spring/spring-boot-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -295,6 +295,12 @@
       "type": "java.util.Map<java.lang.String, java.lang.String>",
       "description": "Used to specify a mapping from host names or IP addresses to peer services, as a comma-separated list of <code>host_or_ip=user_assigned_name</code> pairs. The peer service is added as an attribute to a span whose host or IP address match the mapping. See https://opentelemetry.io/docs/zero-code/java/agent/configuration/#peer-service-name."
     },
+    {
+      "name": "otel.instrumentation.common.thread-details.enabled",
+      "type": "java.lang.Boolean",
+      "description": "Enable the capture of thread details (thread id and thread name) as span attributes.",
+      "defaultValue": false
+    },
     {
       "name": "otel.instrumentation.http.client.capture-request-headers",
       "type": "java.util.List<java.lang.String>",
@@ -627,6 +633,12 @@
       "description": "The maximum number of links per span.",
       "defaultValue": 128
     },
+    {
+      "name": "otel.spring-starter.debug",
+      "type": "java.lang.Boolean",
+      "description": "Print spans to console for debugging purposes.",
+      "defaultValue": false
+    },
     {
       "name": "otel.traces.exporter",
       "type": "java.util.List<java.lang.String>",

instrumentation/spring/spring-boot-autoconfigure/src/test/java/io/opentelemetry/instrumentation/spring/autoconfigure/internal/instrumentation/logging/LoggingExporterAutoConfigurationTest.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.spring.autoconfigure.internal.instrumentation.logging;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import io.opentelemetry.api.OpenTelemetry;
+import io.opentelemetry.instrumentation.spring.autoconfigure.OpenTelemetryAutoConfiguration;
+import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
+import io.opentelemetry.sdk.autoconfigure.spi.internal.DefaultConfigProperties;
+import java.util.Collections;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+
+class LoggingExporterAutoConfigurationTest {
+  private final ApplicationContextRunner runner =
+      new ApplicationContextRunner()
+          .withBean(
+              ConfigProperties.class,
+              () -> DefaultConfigProperties.createFromMap(Collections.emptyMap()))
+          .withConfiguration(
+              AutoConfigurations.of(
+                  LoggingExporterAutoConfiguration.class, OpenTelemetryAutoConfiguration.class));
+
+  @Test
+  void debugEnabled() {
+    runner
+        .withPropertyValues("otel.spring-starter.debug=true", "otel.traces.exporter=none")
+        .run(
+            context ->
+                assertThat(context.getBean(OpenTelemetry.class).toString())
+                    .containsOnlyOnce("LoggingSpanExporter"));
+  }
+
+  @Test
+  void alreadyAdded() {
+    runner
+        .withPropertyValues("otel.spring-starter.debug=true", "otel.traces.exporter=logging")
+        .run(
+            context ->
+                assertThat(context.getBean(OpenTelemetry.class).toString())
+                    .containsOnlyOnce("LoggingSpanExporter"));
+  }
+
+  @Test
+  void debugUnset() {
+    runner.run(
+        context ->
+            assertThat(context.getBean(OpenTelemetry.class).toString())
+                .doesNotContain("LoggingSpanExporter"));
+  }
+
+  @Test
+  void debugDisabled() {
+    runner
+        .withPropertyValues("otel.spring-starter.debug=false", "otel.traces.exporter=none")
+        .run(
+            context ->
+                assertThat(context.getBean(OpenTelemetry.class).toString())
+                    .doesNotContain("LoggingSpanExporter"));
+  }
+}