fix: skip OData services with null EntityContainer to prevent NPE

src/main/java/io/neonbee/endpoint/odatav4/ODataV4Endpoint.java

@@ -268,6 +268,16 @@ protected Future<Void> refreshRouter(Vertx vertx, Router router, String basePath
             models.values().stream()
                     .filter(this::filterModels)
                     .flatMap(entityModel -> entityModel.getAllEdmxMetadata().entrySet().stream())
+                    .filter(entry -> {
+                        if (entry.getValue().getEdm().getEntityContainer() == null) {
+                            if (LOGGER.isErrorEnabled()) {
+                                LOGGER.error("Skipping OData service endpoint for {} — EntityContainer is null",
+                                        entry.getKey());
+                            }
+                            return false;
+                        }
+                        return true;
+                    })
                     .map(entryFunction(
                             (schemaNamespace, edmxModel) -> Map.entry(uriConversion.apply(schemaNamespace), edmxModel)))
                     .sorted(Map.Entry.comparingByKey(Comparator.comparingInt(String::length).reversed()))

src/main/java/io/neonbee/entity/EntityModelLoader.java

@@ -216,7 +216,12 @@ Future<Void> parseModel(String csnFile, byte[] csnPayload, Map<String, byte[]> a
             return Future.all(EntityModelDefinition.resolveEdmxPaths(Path.of(csnFile), cdsModel).stream()
                     .map(Path::toString).map(path -> {
                         // we do not know if the path uses windows / unix path separators, try both!
-                        return FileSystemHelper.getPathFromMap(associatedModels, path);
+                        byte[] payload = FileSystemHelper.getPathFromMap(associatedModels, path);
+                        if (payload == null && LOGGER.isWarnEnabled()) {
+                            LOGGER.warn("Associated model {} not found in associatedModels map (keys={})", path,
+                                    associatedModels.keySet());
+                        }
+                        return payload;
                     }).map(this::parseEdmxModel).toList()).onComplete(result -> {
                         if (LOGGER.isTraceEnabled()) {
                             LOGGER.trace("Parsing associated models of {} {}", csnFile,
@@ -244,6 +249,7 @@ private void buildModelMap(CdsModel cdsModel, List<ServiceMetadata> edmxModels)
         }
 
         Map<String, ServiceMetadata> edmxMap = edmxModels.stream()
+                .filter(java.util.Objects::nonNull)
                 .collect(Collectors.toMap(EntityModelLoader::getSchemaNamespace, Function.identity()));
         if (models.put(namespace, EntityModel.of(cdsModel, edmxMap)) != null) {
             LOGGER.warn("Model with schema namespace {} replaced an existing model in the model map", namespace);

src/test/java/io/neonbee/endpoint/odatav4/ODataV4EndpointTest.java

@@ -69,7 +69,8 @@ class ODataV4EndpointTest extends ODataEndpointTestBase {
     @Override
     protected List<Path> provideEntityModels() {
         return List.of(TEST_RESOURCES.resolveRelated("TestService1.csn"),
-                TEST_RESOURCES.resolveRelated("TestService2.csn"), TEST_RESOURCES.resolveRelated("TestService3.csn"));
+                TEST_RESOURCES.resolveRelated("TestService2.csn"), TEST_RESOURCES.resolveRelated("TestService3.csn"),
+                TEST_RESOURCES.resolveRelated("EmptyContainerService.csn"));
     }
 
     @Override
@@ -101,6 +102,23 @@ void testODataEndpointLazyLoading(VertxTestContext testContext) {
                         .onComplete(testContext.succeedingThenComplete());
     }
 
+    @Test
+    @DisplayName("service with empty EntityContainer is skipped, other services still registered")
+    void testEmptyEntityContainerServiceIsSkipped(VertxTestContext testContext) {
+        requestMetadata("io.neonbee.handler.empty.EmptyContainerService")
+                .compose(emptyResp -> {
+                    testContext.verify(() -> assertThat(emptyResp.statusCode()).isEqualTo(HTTP_NOT_FOUND));
+                    return requestMetadata("io.neonbee.handler.TestService");
+                })
+                .onComplete(testContext.succeeding(validResp -> {
+                    testContext.verify(() -> {
+                        assertThat(validResp.statusCode()).isEqualTo(200);
+                        assertThat(validResp.body().toString()).contains("<edmx:Edmx");
+                    });
+                    testContext.completeNow();
+                }));
+    }
+
     @Test
     void testUriConversionRules() {
         // strict should not convert anything!

src/test/java/io/neonbee/entity/EntityModelLoaderTest.java

@@ -16,7 +16,8 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.TestInfo;
 
-import com.sap.cds.reflect.CdsModel;
+import com.sap.cds.reflect.CdsEntity;
+import com.sap.cds.reflect.CdsService;
 
 import io.neonbee.NeonBeeOptions;
 import io.neonbee.test.base.NeonBeeTestBase;
@@ -120,12 +121,14 @@ void loadFromModuleTest(Vertx vertx, VertxTestContext testContext) throws IOExce
     @DisplayName("check if getting CSN Model works")
     void getCSNModelTest(Vertx vertx, VertxTestContext testContext) {
         EntityModelLoader loader = new EntityModelLoader(vertx);
-        Future<CdsModel> csnModelFuture = loader.readCsnModel(TEST_SERVICE_1_MODEL_PATH);
-        csnModelFuture.compose(v -> loader.loadModel(TEST_SERVICE_1_MODEL_PATH))
-                .onComplete(testContext.succeeding(result -> testContext.verify(() -> {
-                    CdsModel expectedCsnModel = csnModelFuture.result();
-                    EntityModel model = loader.models.get("io.neonbee.test1");
-                    assertThat(model.getCsnModel()).isEqualTo(expectedCsnModel);
+        loader.loadModel(TEST_SERVICE_1_MODEL_PATH)
+                .onComplete(testContext.succeeding(v -> testContext.verify(() -> {
+                    var csnModel = loader.models.get("io.neonbee.test1").getCsnModel();
+                    assertThat(csnModel.services().map(CdsService::getQualifiedName).toList())
+                            .containsExactly("io.neonbee.test1.TestService1");
+                    assertThat(csnModel.entities().map(CdsEntity::getQualifiedName).toList())
+                            .containsExactly("io.neonbee.test1.TestService1.AllPropertiesNullable",
+                                    "io.neonbee.test.TestService1.TestProducts");
                     testContext.completeNow();
                 })));
     }

src/test/resources/io/neonbee/endpoint/odatav4/EmptyContainerService.csn

@@ -0,0 +1,12 @@
+{
+  "namespace": "io.neonbee.handler.empty",
+  "definitions": {
+    "io.neonbee.handler.empty.EmptyContainerService": {
+      "kind": "service"
+    }
+  },
+  "meta": {
+    "creator": "CDS Compiler v1.26.2"
+  },
+  "$version": "1.0"
+}

src/test/resources/io/neonbee/endpoint/odatav4/io.neonbee.handler.empty.EmptyContainerService.edmx

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<edmx:Edmx Version="4.0" xmlns:edmx="http://docs.oasis-open.org/odata/ns/edmx">
+  <edmx:DataServices>
+    <Schema Namespace="io.neonbee.handler.empty.EmptyContainerService" xmlns="http://docs.oasis-open.org/odata/ns/edm"/>
+  </edmx:DataServices>
+</edmx:Edmx>