[WIP][REST] New API to transform to/from DSL file format (items & things)

bundles/org.openhab.core.io.rest.core/src/main/java/org/openhab/core/io/rest/core/fileformat/FileFormatDTO.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2010-2025 Contributors to the openHAB project
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package org.openhab.core.io.rest.core.fileformat;
+
+import java.util.List;
+
+import org.openhab.core.items.dto.ItemDTO;
+import org.openhab.core.thing.dto.ThingDTO;
+import org.openhab.core.thing.link.dto.ItemChannelLinkDTO;
+
+/**
+ * This is a data transfer object that is used to serialize different components that can be embedded
+ * inside a file format, like items, metadata, channel links, things, ...
+ *
+ * @author Laurent Garnier - Initial contribution
+ */
+public class FileFormatDTO {
+
+    public List<ItemDTO> items;
+    public List<MetadataDTO> metadata;
+    public List<ItemChannelLinkDTO> channelLinks;
+    public List<ThingDTO> things;
+}

bundles/org.openhab.core.io.rest.core/src/main/java/org/openhab/core/io/rest/core/fileformat/MetadataDTO.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2010-2025 Contributors to the openHAB project
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package org.openhab.core.io.rest.core.fileformat;
+
+import java.util.Map;
+
+/**
+ * This is a data transfer object that is used to serialize a metadata.
+ *
+ * @author Laurent Garnier - Initial contribution
+ */
+public class MetadataDTO {
+
+    public String itemName;
+    public String namespace;
+    public String value;
+    public Map<String, Object> configuration;
+
+    public MetadataDTO(String itemName, String namespace, String value, Map<String, Object> configuration) {
+        this.itemName = itemName;
+        this.namespace = namespace;
+        this.value = value;
+        this.configuration = configuration;
+    }
+}

bundles/org.openhab.core.io.rest.core/src/main/java/org/openhab/core/io/rest/core/fileformat/ParsedFileFormatDTO.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2010-2025 Contributors to the openHAB project
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package org.openhab.core.io.rest.core.fileformat;
+
+import java.util.List;
+
+/**
+ * This is a data transfer object that is used to serialize the result of file format parsing.
+ *
+ * @author Laurent Garnier - Initial contribution
+ */
+public class ParsedFileFormatDTO extends FileFormatDTO {
+
+    public List<String> warnings;
+}

bundles/org.openhab.core.model.core/src/main/java/org/openhab/core/model/core/ModelRepository.java

@@ -14,6 +14,7 @@
 
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.util.List;
 import java.util.Set;
 
 import org.eclipse.emf.ecore.EObject;
@@ -28,6 +29,7 @@
  *
  * @author Kai Kreuzer - Initial contribution
  * @author Laurent Garnier - Added method generateSyntaxFromModel
+ * @author Laurent Garnier - Added methods addStandaloneModel and removeStandaloneModel
  */
 @NonNullByDefault
 public interface ModelRepository {
@@ -95,6 +97,27 @@ public interface ModelRepository {
      */
     void removeModelRepositoryChangeListener(ModelRepositoryChangeListener listener);
 
+    /**
+     * Adds a standalone model to the repository
+     * A standalone model will be loaded without triggering any listener.
+     *
+     * @param modelType the model type
+     * @param inputStream an input stream with the model's content
+     * @param errors the list to be used to fill the errors
+     * @param warnings the list to be used to fill the warnings
+     * @return the created model name if it was successfully processed, null otherwise
+     */
+    @Nullable
+    String addStandaloneModel(String modelType, InputStream inputStream, List<String> errors, List<String> warnings);
+
+    /**
+     * Removes a standalone model from the repository
+     *
+     * @param name the name of the model to remove
+     * @return true, if model was removed, false, if it did not exist
+     */
+    boolean removeStandaloneModel(String name);
+
     /**
      * Generate the syntax from a provided model content.
      *

bundles/org.openhab.core.model.core/src/main/java/org/openhab/core/model/core/internal/ModelRepositoryImpl.java

@@ -20,7 +20,6 @@
 import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.HashSet;
-import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -52,6 +51,7 @@
  * @author Oliver Libutzki - Added reloadAllModelsOfType method
  * @author Simon Kaufmann - added validation of models before loading them
  * @author Laurent Garnier - Added method generateSyntaxFromModel
+ * @author Laurent Garnier - Added methods addStandaloneModel and removeStandaloneModel
  */
 @Component(immediate = true)
 @NonNullByDefault
@@ -100,17 +100,37 @@ public ModelRepositoryImpl(final @Reference SafeEMF safeEmf) {
 
     @Override
     public boolean addOrRefreshModel(String name, final InputStream originalInputStream) {
+        return addOrRefreshModel(name, originalInputStream, null, null, false);
+    }
+
+    public boolean addOrRefreshModel(String name, final InputStream originalInputStream, @Nullable List<String> errors,
+            @Nullable List<String> warnings, boolean standalone) {
         logger.info("Loading model '{}'", name);
         Resource resource = null;
         byte[] bytes;
         try (InputStream inputStream = originalInputStream) {
             bytes = inputStream.readAllBytes();
-            String validationResult = validateModel(name, new ByteArrayInputStream(bytes));
-            if (validationResult != null) {
-                logger.warn("Configuration model '{}' has errors, therefore ignoring it: {}", name, validationResult);
+            List<String> newErrors = new ArrayList<>();
+            List<String> newWarnings = new ArrayList<>();
+            boolean valid = validateModel(name, new ByteArrayInputStream(bytes), newErrors, newWarnings);
+            if (errors != null) {
+                errors.addAll(newErrors);
+            }
+            if (warnings != null) {
+                warnings.addAll(newWarnings);
+            }
+            if (!valid) {
+                if (!standalone) {
+                    logger.warn("Configuration model '{}' has errors, therefore ignoring it: {}", name,
+                            String.join("\n", newErrors));
+                }
                 removeModel(name);
                 return false;
             }
+            if (!standalone && !newWarnings.isEmpty()) {
+                logger.info("Validation issues found in configuration model '{}', using it anyway:\n{}", name,
+                        String.join("\n", newWarnings));
+            }
         } catch (IOException e) {
             logger.warn("Configuration model '{}' cannot be parsed correctly!", name, e);
             return false;
@@ -128,7 +148,9 @@ public boolean addOrRefreshModel(String name, final InputStream originalInputStr
                         resource = resourceSet.createResource(URI.createURI(name));
                         if (resource != null) {
                             resource.load(inputStream, resourceOptions);
-                            notifyListeners(name, EventType.ADDED);
+                            if (!standalone) {
+                                notifyListeners(name, EventType.ADDED);
+                            }
                             return true;
                         } else {
                             logger.warn("Ignoring file '{}' as we do not have a parser for it.", name);
@@ -139,7 +161,9 @@ public boolean addOrRefreshModel(String name, final InputStream originalInputStr
                 synchronized (resourceSet) {
                     resource.unload();
                     resource.load(inputStream, resourceOptions);
-                    notifyListeners(name, EventType.MODIFIED);
+                    if (!standalone) {
+                        notifyListeners(name, EventType.MODIFIED);
+                    }
                     return true;
                 }
             }
@@ -154,11 +178,17 @@ public boolean addOrRefreshModel(String name, final InputStream originalInputStr
 
     @Override
     public boolean removeModel(String name) {
+        return removeModel(name, false);
+    }
+
+    private boolean removeModel(String name, boolean standalone) {
         Resource resource = getResource(name);
         if (resource != null) {
             synchronized (resourceSet) {
                 // do not physically delete it, but remove it from the resource set
-                notifyListeners(name, EventType.REMOVED);
+                if (!standalone) {
+                    notifyListeners(name, EventType.REMOVED);
+                }
                 resourceSet.getResources().remove(resource);
                 return true;
             }
@@ -232,6 +262,18 @@ public void removeModelRepositoryChangeListener(ModelRepositoryChangeListener li
         listeners.remove(listener);
     }
 
+    @Override
+    public @Nullable String addStandaloneModel(String modelType, InputStream inputStream, List<String> errors,
+            List<String> warnings) {
+        String name = "tmp_syntax_%d.%s".formatted(++counter, modelType);
+        return addOrRefreshModel(name, inputStream, errors, warnings, true) ? name : null;
+    }
+
+    @Override
+    public boolean removeStandaloneModel(String name) {
+        return removeModel(name, true);
+    }
+
     @Override
     public void generateSyntaxFromModel(OutputStream out, String modelType, EObject modelContent) {
         String result = "";
@@ -269,28 +311,28 @@ public void generateSyntaxFromModel(OutputStream out, String modelType, EObject
      * Validation will be done on a separate resource, in order to keep the original one intact in case its content
      * needs to be removed because of syntactical errors.
      *
-     * @param name
-     * @param inputStream
-     * @return error messages as a String if any syntactical error were found, <code>null</code> otherwise
+     * @param name the model name
+     * @param inputStream an input stream with the model's content
+     * @param errors the list to be used to fill the errors
+     * @param warnings the list to be used to fill the warnings
+     * @return false if any syntactical error were found, false otherwise
      * @throws IOException if there was an error with the given {@link InputStream}, loading the resource from there
      */
-    private @Nullable String validateModel(String name, InputStream inputStream) throws IOException {
+    private boolean validateModel(String name, InputStream inputStream, List<String> errors, List<String> warnings)
+            throws IOException {
         // use another resource for validation in order to keep the original one for emergency-removal in case of errors
         Resource resource = resourceSet.createResource(URI.createURI("tmp_" + name));
         try {
             resource.load(inputStream, resourceOptions);
-            StringBuilder criticalErrors = new StringBuilder();
-            List<String> warnings = new LinkedList<>();
 
             if (!resource.getContents().isEmpty()) {
                 // Check for syntactical errors
                 for (Diagnostic diagnostic : resource.getErrors()) {
-                    criticalErrors
-                            .append(MessageFormat.format("[{0},{1}]: {2}\n", Integer.toString(diagnostic.getLine()),
-                                    Integer.toString(diagnostic.getColumn()), diagnostic.getMessage()));
+                    errors.add(MessageFormat.format("[{0},{1}]: {2}", Integer.toString(diagnostic.getLine()),
+                            Integer.toString(diagnostic.getColumn()), diagnostic.getMessage()));
                 }
-                if (!criticalErrors.isEmpty()) {
-                    return criticalErrors.toString();
+                if (!resource.getErrors().isEmpty()) {
+                    return false;
                 }
 
                 // Check for validation errors, but log them only
@@ -300,10 +342,6 @@ public void generateSyntaxFromModel(OutputStream out, String modelType, EObject
                     for (org.eclipse.emf.common.util.Diagnostic d : diagnostic.getChildren()) {
                         warnings.add(d.getMessage());
                     }
-                    if (!warnings.isEmpty()) {
-                        logger.info("Validation issues found in configuration model '{}', using it anyway:\n{}", name,
-                                String.join("\n", warnings));
-                    }
                 } catch (NullPointerException e) {
                     // see https://github.com/eclipse/smarthome/issues/3335
                     logger.debug("Validation of '{}' skipped due to internal errors.", name);
@@ -312,7 +350,7 @@ public void generateSyntaxFromModel(OutputStream out, String modelType, EObject
         } finally {
             resourceSet.getResources().remove(resource);
         }
-        return null;
+        return true;
     }
 
     private void notifyListeners(String name, EventType type) {

bundles/org.openhab.core.model.item/src/org/openhab/core/model/item/internal/GenericItemProvider.java

@@ -15,6 +15,7 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -67,11 +68,13 @@
  *
  * @author Kai Kreuzer - Initial contribution
  * @author Thomas Eichstaedt-Engelen - Initial contribution
+ * @author Laurent Garnier - Add interface StandaloneItemProvider
  */
 @NonNullByDefault
-@Component(service = { ItemProvider.class, StateDescriptionFragmentProvider.class }, immediate = true)
-public class GenericItemProvider extends AbstractProvider<Item>
-        implements ModelRepositoryChangeListener, ItemProvider, StateDescriptionFragmentProvider {
+@Component(service = { ItemProvider.class, StandaloneItemProvider.class,
+        StateDescriptionFragmentProvider.class }, immediate = true)
+public class GenericItemProvider extends AbstractProvider<Item> implements ModelRepositoryChangeListener, ItemProvider,
+        StandaloneItemProvider, StateDescriptionFragmentProvider {
 
     private final Logger logger = LoggerFactory.getLogger(GenericItemProvider.class);
 
@@ -170,7 +173,7 @@ public Collection<Item> getAll() {
         return items;
     }
 
-    private Collection<Item> getItemsFromModel(String modelName) {
+    private List<Item> getItemsFromModel(String modelName) {
         logger.debug("Read items from model '{}'", modelName);
 
         List<Item> items = new ArrayList<>();
@@ -521,6 +524,14 @@ private Map<String, Item> toItemMap(@Nullable Collection<Item> items) {
         return null;
     }
 
+    @Override
+    public List<Item> getItemsFromStandaloneModel(String modelName) {
+        if (modelName.endsWith("items")) {
+            return getItemsFromModel(modelName);
+        }
+        return Collections.emptyList();
+    }
+
     @Override
     public @Nullable StateDescriptionFragment getStateDescriptionFragment(String itemName, @Nullable Locale locale) {
         return stateDescriptionFragments.get(itemName);