Configure jsonSchema2Pojo to not initialize collections

sdk-extensions/declarative-config/build.gradle.kts

@@ -107,6 +107,12 @@ jsonSchema2Pojo {
 
   // Append Model as suffix to the generated classes.
   classNameSuffix = "Model"
+
+  // Initialize collection fields to null rather than empty collections so that absent YAML
+  // properties deserialize as null (not present) rather than [] (explicitly empty). This lets
+  // factories distinguish between "user omitted the field" and "user provided an empty list",
+  // which is important for validations like IncludeExcludeFactory.
+  initializeCollections = false
 }
 
 val generateJsonSchema2Pojo = tasks.getByName("generateJsonSchema2Pojo")

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/ComposableRuleBasedSamplerFactory.java

@@ -54,12 +54,10 @@ public ComposableSampler create(
           rule -> {
             AttributeMatcher valueMatcher = attributeValuesMatcher(rule.getAttributeValues());
             AttributeMatcher patternMatcher = attributePatternsMatcher(rule.getAttributePatterns());
-            // TODO: should be null when omitted but is empty
             Set<ExperimentalSpanParent> matchingParents =
                 rule.getParent() != null && !rule.getParent().isEmpty()
                     ? new HashSet<>(rule.getParent())
                     : null;
-            // TODO: should be null when omitted but is empty
             Set<SpanKind> matchingSpanKinds =
                 rule.getSpanKinds() != null && !rule.getSpanKinds().isEmpty()
                     ? rule.getSpanKinds().stream()

sdk-extensions/declarative-config/src/test/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/ComposableRuleBasedSamplerFactoryTest.java

@@ -135,6 +135,33 @@ private static Stream<Arguments> createTestCases() {
         Arguments.of(
             new ExperimentalComposableRuleBasedSamplerModel(),
             ComposableSampler.ruleBasedBuilder().build()),
+        // attributePatterns with only included (no excluded) - analogous to
+        // https://github.com/open-telemetry/opentelemetry-java/issues/8337
+        Arguments.of(
+            new ExperimentalComposableRuleBasedSamplerModel()
+                .withRules(
+                    Collections.singletonList(
+                        new ExperimentalComposableRuleBasedSamplerRuleModel()
+                            .withAttributePatterns(
+                                new ExperimentalComposableRuleBasedSamplerRuleAttributePatternsModel()
+                                    .withKey("http.path")
+                                    .withIncluded(Collections.singletonList("/internal/*")))
+                            .withSampler(
+                                new ExperimentalComposableSamplerModel()
+                                    .withAlwaysOn(
+                                        new ExperimentalComposableAlwaysOnSamplerModel())))),
+            ComposableSampler.ruleBasedBuilder()
+                .add(
+                    new DeclarativeConfigSamplingPredicate(
+                        null,
+                        new AttributeMatcher(
+                            "http.path",
+                            IncludeExcludePredicate.createPatternMatching(
+                                Collections.singletonList("/internal/*"), null)),
+                        null,
+                        null),
+                    ComposableSampler.alwaysOn())
+                .build()),
         // Recreate example
         Arguments.of(
             new ExperimentalComposableRuleBasedSamplerModel()

sdk-extensions/declarative-config/src/test/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/ViewFactoryTest.java

@@ -18,56 +18,65 @@
 import io.opentelemetry.sdk.metrics.View;
 import java.util.Arrays;
 import java.util.Collections;
-import org.junit.jupiter.api.Test;
+import java.util.stream.Stream;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
 
 class ViewFactoryTest {
 
-  @Test
-  void create_Defaults() {
-    View expectedView = View.builder().build();
-
-    View view =
-        ViewFactory.getInstance()
-            .create(
-                new ViewStreamModel().withAttributeKeys(null),
-                mock(DeclarativeConfigContext.class));
-
+  @ParameterizedTest
+  @MethodSource("createArguments")
+  void create(ViewStreamModel model, View expectedView) {
+    View view = ViewFactory.getInstance().create(model, mock(DeclarativeConfigContext.class));
     assertThat(view.toString()).isEqualTo(expectedView.toString());
   }
 
-  @Test
-  void create() {
-    View expectedView =
-        View.builder()
-            .setName("name")
-            .setDescription("description")
-            .setAttributeFilter(
-                IncludeExcludePredicate.createPatternMatching(
-                    Arrays.asList("foo", "bar"), Collections.singletonList("baz")))
-            .setAggregation(
-                Aggregation.explicitBucketHistogram(
-                    ExplicitBucketHistogramOptions.builder()
-                        .setBucketBoundaries(Arrays.asList(1.0, 2.0))
-                        .build()))
-            .build();
-
-    View view =
-        ViewFactory.getInstance()
-            .create(
-                new ViewStreamModel()
-                    .withName("name")
-                    .withDescription("description")
-                    .withAttributeKeys(
-                        new IncludeExcludeModel()
-                            .withIncluded(Arrays.asList("foo", "bar"))
-                            .withExcluded(Collections.singletonList("baz")))
-                    .withAggregation(
-                        new AggregationModel()
-                            .withExplicitBucketHistogram(
-                                new ExplicitBucketHistogramAggregationModel()
-                                    .withBoundaries(Arrays.asList(1.0, 2.0)))),
-                mock(DeclarativeConfigContext.class));
-
-    assertThat(view.toString()).isEqualTo(expectedView.toString());
+  private static Stream<Arguments> createArguments() {
+    return Stream.of(
+        // defaults
+        Arguments.of(new ViewStreamModel().withAttributeKeys(null), View.builder().build()),
+        // attribute_keys with only included (no excluded) - reproduces
+        // https://github.com/open-telemetry/opentelemetry-java/issues/8337
+        Arguments.of(
+            new ViewStreamModel()
+                .withAttributeKeys(
+                    new IncludeExcludeModel()
+                        .withIncluded(
+                            Arrays.asList(
+                                "url.full", "http.request.method", "http.response.status_code"))),
+            View.builder()
+                .setAttributeFilter(
+                    IncludeExcludePredicate.createPatternMatching(
+                        Arrays.asList(
+                            "url.full", "http.request.method", "http.response.status_code"),
+                        null))
+                .build()),
+        // full configuration
+        Arguments.of(
+            new ViewStreamModel()
+                .withName("name")
+                .withDescription("description")
+                .withAttributeKeys(
+                    new IncludeExcludeModel()
+                        .withIncluded(Arrays.asList("foo", "bar"))
+                        .withExcluded(Collections.singletonList("baz")))
+                .withAggregation(
+                    new AggregationModel()
+                        .withExplicitBucketHistogram(
+                            new ExplicitBucketHistogramAggregationModel()
+                                .withBoundaries(Arrays.asList(1.0, 2.0)))),
+            View.builder()
+                .setName("name")
+                .setDescription("description")
+                .setAttributeFilter(
+                    IncludeExcludePredicate.createPatternMatching(
+                        Arrays.asList("foo", "bar"), Collections.singletonList("baz")))
+                .setAggregation(
+                    Aggregation.explicitBucketHistogram(
+                        ExplicitBucketHistogramOptions.builder()
+                            .setBucketBoundaries(Arrays.asList(1.0, 2.0))
+                            .build()))
+                .build()));
   }
 }