Adds Pagination on Backend (AAS Repo)

Author: FriedJannik

basyx.aasservice/basyx.aasservice-backend-inmemory/src/main/java/org/eclipse/digitaltwin/basyx/aasservice/backend/InMemoryAasBackend.java

@@ -40,6 +40,7 @@
 import java.util.TreeMap;
 import java.util.function.Function;
 import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
 
 /**
  * Implements the AasService as in-memory variant
@@ -55,6 +56,18 @@ public InMemoryAasBackend() {
 		super(AssetAdministrationShell::getId);
 	}
 
+	@Override
+	public CursorResult<List<AssetAdministrationShell>> getShells(List<SpecificAssetId> assetIds, String idShort, PaginationInfo pInfo) {
+		Iterable<AssetAdministrationShell> iterable = getAllAas(assetIds, idShort);
+		List<AssetAdministrationShell> allAas = StreamSupport.stream(iterable.spliterator(), false).toList();
+
+		TreeMap<String, AssetAdministrationShell> aasMap = allAas.stream().collect(Collectors.toMap(AssetAdministrationShell::getId, aas -> aas, (a, b) -> a, TreeMap::new));
+
+		PaginationSupport<AssetAdministrationShell> paginationSupport = new PaginationSupport<>(aasMap, AssetAdministrationShell::getId);
+
+		return paginationSupport.getPaged(pInfo);
+	}
+
 	@Override
 	public CursorResult<List<Reference>> getSubmodelReferences(String aasId, PaginationInfo pInfo) {
 		List<Reference> submodelReferences = getAas(aasId).getSubmodels();

basyx.aasservice/basyx.aasservice-backend-mongodb/src/main/java/org/eclipse/digitaltwin/basyx/aasservice/backend/MongoDBAasOperations.java

@@ -34,6 +34,7 @@
 import org.eclipse.digitaltwin.basyx.core.exceptions.ElementDoesNotExistException;
 import org.eclipse.digitaltwin.basyx.core.pagination.CursorResult;
 import org.eclipse.digitaltwin.basyx.core.pagination.PaginationInfo;
+import org.springframework.data.domain.Sort;
 import org.springframework.data.mongodb.core.MongoOperations;
 import org.springframework.data.mongodb.core.aggregation.Aggregation;
 import org.springframework.data.mongodb.core.aggregation.AggregationOperation;
@@ -67,6 +68,42 @@ public MongoDBAasOperations(MongoOperations mongoOperations) {
         collectionName = mongoOperations.getCollectionName(AssetAdministrationShell.class);
     }
 
+    @Override
+    public CursorResult<List<AssetAdministrationShell>> getShells(List<SpecificAssetId> assetIds, String idShort, PaginationInfo pInfo) {
+        List<AggregationOperation> ops = new ArrayList<>();
+
+        List<Criteria> criteriaList = buildAasFilterCriteria(assetIds, idShort);
+        if (!criteriaList.isEmpty()) {
+            ops.add(Aggregation.match(new Criteria().andOperator(criteriaList.toArray(new Criteria[0]))));
+        }
+
+        // Apply cursor (_id > cursor)
+        if (hasCursor(pInfo)) {
+            ops.add(Aggregation.match(Criteria.where("_id").gt(pInfo.getCursor())));
+        }
+
+        // Sort for stable pagination
+        ops.add(Aggregation.sort(Sort.by(Sort.Direction.ASC, "_id")));
+
+        // Apply limit
+        if (hasLimit(pInfo)) {
+            ops.add(Aggregation.limit(pInfo.getLimit()));
+        }
+
+        // Run aggregation
+        Aggregation aggregation = Aggregation.newAggregation(ops);
+        AggregationResults<AssetAdministrationShell> results =
+                mongoOperations.aggregate(aggregation, collectionName, AssetAdministrationShell.class);
+
+        List<AssetAdministrationShell> shells = results.getMappedResults();
+
+        String nextCursor = shells.isEmpty()
+                ? null
+                : shells.get(shells.size() - 1).getId();
+
+        return new CursorResult<>(nextCursor, shells);
+    }
+
 
     @Override
     public CursorResult<List<Reference>> getSubmodelReferences(@NonNull String aasId, @NonNull PaginationInfo pInfo) throws ElementDoesNotExistException {
@@ -174,29 +211,10 @@ public AssetInformation getAssetInformation(@NonNull String aasId) {
     @Override
     public Iterable<AssetAdministrationShell> getAllAas(List<SpecificAssetId> assetIds, String idShort) {
         Query query = new Query();
-        Criteria criteria = new Criteria();
-
-        String globalAssetId = null;
-        try {
-            globalAssetId = assetIds.stream().filter(assetId -> assetId.getName().equals("globalAssetId")).findFirst().get().getValue();
-            assetIds = assetIds.stream().filter(assetId -> !assetId.getName().equals("globalAssetId")).collect(Collectors.toList());
-        } catch (Exception ignored) {}
+        List<Criteria> criteriaList = buildAasFilterCriteria(assetIds, idShort);
 
-        if (assetIds != null && !assetIds.isEmpty()) {
-            List<Criteria> assetIdCriteria = new ArrayList<>();
-            for (SpecificAssetId assetId : assetIds) {
-                assetIdCriteria.add(Criteria.where("assetInformation.specificAssetIds.name").is(assetId.getName()));
-                assetIdCriteria.add(Criteria.where("assetInformation.specificAssetIds.value").is(assetId.getValue()));
-            }
-            criteria.andOperator(assetIdCriteria);
-        }
-        if (idShort != null && !idShort.isEmpty()) {
-            criteria.and("idShort").is(idShort);
-        }
-        query.addCriteria(criteria);
-
-        if (globalAssetId != null && !globalAssetId.isEmpty()) {
-            query.addCriteria(Criteria.where("assetInformation.globalAssetId").is(globalAssetId));
+        if (!criteriaList.isEmpty()) {
+            query.addCriteria(new Criteria().andOperator(criteriaList.toArray(new Criteria[0])));
         }
 
         return mongoOperations.find(query, AssetAdministrationShell.class, collectionName);
@@ -217,4 +235,52 @@ private static String extractSubmodelId(Reference reference) {
 
         return "";
     }
+
+    private List<Criteria> buildAasFilterCriteria(List<SpecificAssetId> assetIds, String idShort) {
+        List<Criteria> criteriaList = new ArrayList<>();
+
+        // Extract globalAssetId from assetIds
+        String globalAssetId = null;
+        try {
+            globalAssetId = assetIds.stream()
+                    .filter(assetId -> "globalAssetId".equals(assetId.getName()))
+                    .findFirst()
+                    .map(SpecificAssetId::getValue)
+                    .orElse(null);
+
+            assetIds = assetIds.stream()
+                    .filter(assetId -> !"globalAssetId".equals(assetId.getName()))
+                    .collect(Collectors.toList());
+        } catch (Exception ignored) {}
+
+        // Match specific assetIds (name + value pair inside array)
+        if (assetIds != null && !assetIds.isEmpty()) {
+            for (SpecificAssetId assetId : assetIds) {
+                criteriaList.add(Criteria.where("assetInformation.specificAssetIds")
+                        .elemMatch(Criteria.where("name").is(assetId.getName())
+                                .and("value").is(assetId.getValue())));
+            }
+        }
+
+        // Match idShort if present
+        if (idShort != null && !idShort.isEmpty()) {
+            criteriaList.add(Criteria.where("idShort").is(idShort));
+        }
+
+        // Match globalAssetId if present
+        if (globalAssetId != null && !globalAssetId.isEmpty()) {
+            criteriaList.add(Criteria.where("assetInformation.globalAssetId").is(globalAssetId));
+        }
+
+        return criteriaList;
+    }
+
+    private static boolean hasLimit(PaginationInfo pInfo) {
+        return pInfo.getLimit() != null && pInfo.getLimit() > 0;
+    }
+
+    private static boolean hasCursor(PaginationInfo pInfo) {
+        return pInfo.getCursor() != null && !pInfo.getCursor().isEmpty();
+    }
+
 }

basyx.aasservice/basyx.aasservice-backend/src/main/java/org/eclipse/digitaltwin/basyx/aasservice/backend/AasOperations.java

@@ -44,6 +44,16 @@
  */
 public interface AasOperations {
 
+    /**
+     * Retrieves all Asset Administration Shells
+     *
+     * @param assetIds  List of specific asset IDs to filter AASs
+     * @param idShort   idShort to filter AASs
+     * @param pInfo     the pagination information
+     * @return          a {@code CursorResult} containing a list of Asset Administration Shells
+     */
+    CursorResult<List<AssetAdministrationShell>> getShells(List<SpecificAssetId> assetIds, String idShort, PaginationInfo pInfo);
+
     /**
      * Retrieves all Submodel References for the given AAS.
      *

basyx.submodelservice/basyx.submodelservice-backend-mongodb/src/main/java/org/eclipse/digitaltwin/basyx/submodelservice/backend/MongoDbSubmodelOperations.java

@@ -146,14 +146,6 @@ public CursorResult<List<SubmodelElement>> getSubmodelElements(String submodelId
         return new CursorResult<>(nextCursor, elements);
     }
 
-    private static boolean hasLimit(PaginationInfo pInfo) {
-        return pInfo.getLimit() != null && pInfo.getLimit() > 0;
-    }
-
-    private static boolean hasCursor(PaginationInfo pInfo) {
-        return pInfo.getCursor() != null && !pInfo.getCursor().isEmpty();
-    }
-
     @Override
     public SubmodelElement getSubmodelElement(String submodelId, String idShortPath) throws ElementDoesNotExistException {
         List<AggregationOperation> ops = MongoFilterBuilder.buildAggregationOperations(submodelId, idShortPath);
@@ -334,4 +326,12 @@ private boolean existsSubmodelElement(String submodelId, String idShortPath){
         }
     }
 
+    private static boolean hasLimit(PaginationInfo pInfo) {
+        return pInfo.getLimit() != null && pInfo.getLimit() > 0;
+    }
+
+    private static boolean hasCursor(PaginationInfo pInfo) {
+        return pInfo.getCursor() != null && !pInfo.getCursor().isEmpty();
+    }
+
 }