Fixing copyAttachments api for Projection entities

sdm/src/main/java/com/sap/cds/sdm/constants/SDMConstants.java

@@ -85,6 +85,13 @@ private SDMConstants() {
   public static final String FAILED_TO_FETCH_UP_ID = "Failed to fetch up_id";
   public static final String FAILED_TO_FETCH_FACET =
       "Invalid facet format, unable to extract required information.";
+  public static final String PARENT_ENTITY_NOT_FOUND_ERROR = "Unable to find parent entity: %s";
+  public static final String COMPOSITION_NOT_FOUND_ERROR =
+      "Unable to find composition '%s' in entity: %s";
+  public static final String TARGET_ATTACHMENT_ENTITY_NOT_FOUND_ERROR =
+      "Unable to find target attachment entity: %s";
+  public static final String INVALID_FACET_FORMAT_ERROR =
+      "Invalid facet format. Expected: Service.Entity.Composition, got: %s";
 
   public static String nameConstraintMessage(
       List<String> fileNameWithRestrictedCharacters, String operation) {

sdm/src/main/java/com/sap/cds/sdm/model/CopyAttachmentInput.java

@@ -3,10 +3,12 @@
 import java.util.List;
 
 /**
- * The class {@link CopyAttachmentInput} is used to store the input for creating an attachment.
+ * The class {@link CopyAttachmentInput} is used to store the input for copying attachments. This
+ * model supports both regular entities and projection entities by using facet-based navigation.
  *
- * @param upId The keys for the attachment entity
- * @param facet
- * @param objectIds
+ * @param upId The key of the parent entity instance
+ * @param facet The full facet path (e.g., "Service.Entity.composition") that will be internally
+ *     parsed to determine parent entity and composition name
+ * @param objectIds The list of attachment object IDs to be copied
  */
 public record CopyAttachmentInput(String upId, String facet, List<String> objectIds) {}

sdm/src/main/java/com/sap/cds/sdm/model/CopyAttachmentsRequest.java

@@ -0,0 +1,110 @@
+package com.sap.cds.sdm.model;
+
+import com.sap.cds.sdm.service.handler.AttachmentCopyEventContext;
+import java.util.List;
+
+/**
+ * Parameter object for copyAttachmentsToSDM method to reduce parameter count and improve code
+ * maintainability.
+ */
+public class CopyAttachmentsRequest {
+  private final AttachmentCopyEventContext context;
+  private final List<String> objectIds;
+  private final String folderId;
+  private final String repositoryId;
+  private final SDMCredentials sdmCredentials;
+  private final Boolean isSystemUser;
+  private final boolean folderExists;
+
+  private CopyAttachmentsRequest(Builder builder) {
+    this.context = builder.context;
+    this.objectIds = builder.objectIds;
+    this.folderId = builder.folderId;
+    this.repositoryId = builder.repositoryId;
+    this.sdmCredentials = builder.sdmCredentials;
+    this.isSystemUser = builder.isSystemUser;
+    this.folderExists = builder.folderExists;
+  }
+
+  // Getters
+  public AttachmentCopyEventContext getContext() {
+    return context;
+  }
+
+  public List<String> getObjectIds() {
+    return objectIds;
+  }
+
+  public String getFolderId() {
+    return folderId;
+  }
+
+  public String getRepositoryId() {
+    return repositoryId;
+  }
+
+  public SDMCredentials getSdmCredentials() {
+    return sdmCredentials;
+  }
+
+  public Boolean getIsSystemUser() {
+    return isSystemUser;
+  }
+
+  public boolean isFolderExists() {
+    return folderExists;
+  }
+
+  public static Builder builder() {
+    return new Builder();
+  }
+
+  public static class Builder {
+    private AttachmentCopyEventContext context;
+    private List<String> objectIds;
+    private String folderId;
+    private String repositoryId;
+    private SDMCredentials sdmCredentials;
+    private Boolean isSystemUser;
+    private boolean folderExists;
+
+    public Builder context(AttachmentCopyEventContext context) {
+      this.context = context;
+      return this;
+    }
+
+    public Builder objectIds(List<String> objectIds) {
+      this.objectIds = objectIds;
+      return this;
+    }
+
+    public Builder folderId(String folderId) {
+      this.folderId = folderId;
+      return this;
+    }
+
+    public Builder repositoryId(String repositoryId) {
+      this.repositoryId = repositoryId;
+      return this;
+    }
+
+    public Builder sdmCredentials(SDMCredentials sdmCredentials) {
+      this.sdmCredentials = sdmCredentials;
+      return this;
+    }
+
+    public Builder isSystemUser(Boolean isSystemUser) {
+      this.isSystemUser = isSystemUser;
+      return this;
+    }
+
+    public Builder folderExists(boolean folderExists) {
+      this.folderExists = folderExists;
+      return this;
+    }
+
+    public CopyAttachmentsRequest build() {
+      return new CopyAttachmentsRequest(this);
+    }
+  }
+}

sdm/src/main/java/com/sap/cds/sdm/model/CreateDraftEntriesRequest.java

@@ -0,0 +1,121 @@
+package com.sap.cds.sdm.model;
+
+import java.util.List;
+
+/**
+ * Parameter object for createDraftEntries method to reduce parameter count and improve code
+ * maintainability.
+ */
+public class CreateDraftEntriesRequest {
+  private final List<List<String>> attachmentsMetadata;
+  private final List<CmisDocument> populatedDocuments;
+  private final String parentEntity;
+  private final String compositionName;
+  private final String upID;
+  private final String upIdKey;
+  private final String repositoryId;
+  private final String folderId;
+
+  private CreateDraftEntriesRequest(Builder builder) {
+    this.attachmentsMetadata = builder.attachmentsMetadata;
+    this.populatedDocuments = builder.populatedDocuments;
+    this.parentEntity = builder.parentEntity;
+    this.compositionName = builder.compositionName;
+    this.upID = builder.upID;
+    this.upIdKey = builder.upIdKey;
+    this.repositoryId = builder.repositoryId;
+    this.folderId = builder.folderId;
+  }
+
+  // Getters
+  public List<List<String>> getAttachmentsMetadata() {
+    return attachmentsMetadata;
+  }
+
+  public List<CmisDocument> getPopulatedDocuments() {
+    return populatedDocuments;
+  }
+
+  public String getParentEntity() {
+    return parentEntity;
+  }
+
+  public String getCompositionName() {
+    return compositionName;
+  }
+
+  public String getUpID() {
+    return upID;
+  }
+
+  public String getUpIdKey() {
+    return upIdKey;
+  }
+
+  public String getRepositoryId() {
+    return repositoryId;
+  }
+
+  public String getFolderId() {
+    return folderId;
+  }
+
+  public static Builder builder() {
+    return new Builder();
+  }
+
+  public static class Builder {
+    private List<List<String>> attachmentsMetadata;
+    private List<CmisDocument> populatedDocuments;
+    private String parentEntity;
+    private String compositionName;
+    private String upID;
+    private String upIdKey;
+    private String repositoryId;
+    private String folderId;
+
+    public Builder attachmentsMetadata(List<List<String>> attachmentsMetadata) {
+      this.attachmentsMetadata = attachmentsMetadata;
+      return this;
+    }
+
+    public Builder populatedDocuments(List<CmisDocument> populatedDocuments) {
+      this.populatedDocuments = populatedDocuments;
+      return this;
+    }
+
+    public Builder parentEntity(String parentEntity) {
+      this.parentEntity = parentEntity;
+      return this;
+    }
+
+    public Builder compositionName(String compositionName) {
+      this.compositionName = compositionName;
+      return this;
+    }
+
+    public Builder upID(String upID) {
+      this.upID = upID;
+      return this;
+    }
+
+    public Builder upIdKey(String upIdKey) {
+      this.upIdKey = upIdKey;
+      return this;
+    }
+
+    public Builder repositoryId(String repositoryId) {
+      this.repositoryId = repositoryId;
+      return this;
+    }
+
+    public Builder folderId(String folderId) {
+      this.folderId = folderId;
+      return this;
+    }
+
+    public CreateDraftEntriesRequest build() {
+      return new CreateDraftEntriesRequest(this);
+    }
+  }
+}

sdm/src/main/java/com/sap/cds/sdm/persistence/DBQuery.java

@@ -7,10 +7,14 @@
 import com.sap.cds.ql.Update;
 import com.sap.cds.ql.cqn.CqnSelect;
 import com.sap.cds.ql.cqn.CqnUpdate;
+import com.sap.cds.reflect.CdsAssociationType;
+import com.sap.cds.reflect.CdsElement;
 import com.sap.cds.reflect.CdsEntity;
+import com.sap.cds.reflect.CdsModel;
 import com.sap.cds.sdm.constants.SDMConstants;
 import com.sap.cds.sdm.model.CmisDocument;
 import com.sap.cds.sdm.service.handler.AttachmentCopyEventContext;
+import com.sap.cds.services.ServiceException;
 import com.sap.cds.services.persistence.PersistenceService;
 import java.util.*;
 
@@ -65,31 +69,66 @@ public CmisDocument getObjectIdForAttachmentID(
 
   public CmisDocument getAttachmentForObjectID(
       PersistenceService persistenceService, String id, AttachmentCopyEventContext context) {
-    Optional<CdsEntity> attachmentEntity = context.getModel().findEntity(context.getFacet());
+
+    // Use the new API to resolve the target attachment entity
+    String parentEntity = context.getParentEntity();
+    String compositionName = context.getCompositionName();
+    CdsModel model = context.getModel();
+
+    // Find the parent entity
+    Optional<CdsEntity> optionalParentEntity = model.findEntity(parentEntity);
+    if (optionalParentEntity.isEmpty()) {
+      throw new ServiceException(
+          String.format(SDMConstants.PARENT_ENTITY_NOT_FOUND_ERROR, parentEntity));
+    }
+
+    // Find the composition element in the parent entity
+    Optional<CdsElement> compositionElement =
+        optionalParentEntity.get().findElement(compositionName);
+    if (compositionElement.isEmpty() || !compositionElement.get().getType().isAssociation()) {
+      throw new ServiceException(
+          String.format(SDMConstants.COMPOSITION_NOT_FOUND_ERROR, compositionName, parentEntity));
+    }
+
+    // Get the target entity of the composition
+    CdsAssociationType assocType = (CdsAssociationType) compositionElement.get().getType();
+    String targetEntityName = assocType.getTarget().getQualifiedName();
+
+    // Find the target attachment entity
+    Optional<CdsEntity> attachmentEntity = model.findEntity(targetEntityName);
+    if (attachmentEntity.isEmpty()) {
+      throw new ServiceException(
+          String.format(SDMConstants.TARGET_ATTACHMENT_ENTITY_NOT_FOUND_ERROR, targetEntityName));
+    }
+
+    // Search in active entity first
     CqnSelect q =
         Select.from(attachmentEntity.get())
             .columns("linkUrl", "type")
             .where(doc -> doc.get("objectId").eq(id));
     Result result = persistenceService.run(q);
     Optional<Row> res = result.first();
+
     CmisDocument cmisDocument = new CmisDocument();
     if (res.isPresent()) {
       Row row = res.get();
       cmisDocument.setType(row.get("type") != null ? row.get("type").toString() : null);
       cmisDocument.setUrl(row.get("linkUrl") != null ? row.get("linkUrl").toString() : null);
     } else {
       // Check in draft table as well
-      attachmentEntity = context.getModel().findEntity(context.getFacet() + "_drafts");
-      q =
-          Select.from(attachmentEntity.get())
-              .columns("linkUrl", "type")
-              .where(doc -> doc.get("objectId").eq(id));
-      result = persistenceService.run(q);
-      res = result.first();
-      if (res.isPresent()) {
-        Row row = res.get();
-        cmisDocument.setType(row.get("type") != null ? row.get("type").toString() : null);
-        cmisDocument.setUrl(row.get("linkUrl") != null ? row.get("linkUrl").toString() : null);
+      Optional<CdsEntity> attachmentDraftEntity = model.findEntity(targetEntityName + "_drafts");
+      if (attachmentDraftEntity.isPresent()) {
+        q =
+            Select.from(attachmentDraftEntity.get())
+                .columns("linkUrl", "type")
+                .where(doc -> doc.get("objectId").eq(id));
+        result = persistenceService.run(q);
+        res = result.first();
+        if (res.isPresent()) {
+          Row row = res.get();
+          cmisDocument.setType(row.get("type") != null ? row.get("type").toString() : null);
+          cmisDocument.setUrl(row.get("linkUrl") != null ? row.get("linkUrl").toString() : null);
+        }
       }
     }
     return cmisDocument;

sdm/src/main/java/com/sap/cds/sdm/service/RegisterService.java

@@ -7,5 +7,13 @@ public interface RegisterService extends Service {
   String SDM_NAME = "SDMAttachmentService$Default";
   String EVENT_COPY_ATTACHMENT = "COPY_ATTACHMENT";
 
+  /**
+   * Copies attachments using the facet-based approach. This method supports both regular entities
+   * and projection entities by internally parsing the facet to determine parent entity and
+   * composition name.
+   *
+   * @param input The copy attachment input containing facet and object IDs
+   * @param isSystemUser Whether to use system user flow
+   */
   public void copyAttachments(CopyAttachmentInput input, boolean isSystemUser);
 }