Add dynamic creation of semantic tags

bundles/org.openhab.core.semantics/model/generateTagClasses.groovy

@@ -134,6 +134,10 @@ public class Locations {
     public static Stream<Class<? extends Location>> stream() {
         return LOCATIONS.stream();
     }
+
+    public static boolean add(Class<? extends Location> tag) {
+        return LOCATIONS.add(tag);
+    }
 }
 """)
     file.close()
@@ -172,6 +176,10 @@ public class Equipments {
     public static Stream<Class<? extends Equipment>> stream() {
         return EQUIPMENTS.stream();
     }
+
+    public static boolean add(Class<? extends Equipment> tag) {
+        return EQUIPMENTS.add(tag);
+    }
 }
 """)
     file.close()
@@ -210,6 +218,10 @@ public class Points {
     public static Stream<Class<? extends Point>> stream() {
         return POINTS.stream();
     }
+
+    public static boolean add(Class<? extends Point> tag) {
+        return POINTS.add(tag);
+    }
 }
 """)
     file.close()
@@ -248,6 +260,10 @@ public class Properties {
     public static Stream<Class<? extends Property>> stream() {
         return PROPERTIES.stream();
     }
+
+    public static boolean add(Class<? extends Property> tag) {
+        return PROPERTIES.add(tag);
+    }
 }
 """)
     file.close()

bundles/org.openhab.core.semantics/pom.xml

@@ -20,6 +20,12 @@
       <artifactId>org.openhab.core</artifactId>
       <version>${project.version}</version>
     </dependency>
+    <dependency>
+      <groupId>org.ow2.asm</groupId>
+      <artifactId>asm</artifactId>
+      <version>9.2</version>
+      <scope>provided</scope>
+    </dependency>
   </dependencies>
 
   <profiles>

bundles/org.openhab.core.semantics/src/main/java/org/openhab/core/semantics/SemanticTags.java

@@ -26,19 +26,25 @@
 
 import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.eclipse.jdt.annotation.Nullable;
+import org.objectweb.asm.AnnotationVisitor;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.Opcodes;
 import org.openhab.core.items.Item;
 import org.openhab.core.semantics.model.equipment.Equipments;
 import org.openhab.core.semantics.model.location.Locations;
 import org.openhab.core.semantics.model.point.Measurement;
 import org.openhab.core.semantics.model.point.Points;
 import org.openhab.core.semantics.model.property.Properties;
 import org.openhab.core.types.StateDescription;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * This is a class that gives static access to the semantic tag library.
  * For everything that is not static, the {@link SemanticsService} should be used instead.
  *
  * @author Kai Kreuzer - Initial contribution
+ * @author Jimmy Tanagra - Add the ability to add new tags at runtime
  */
 @NonNullByDefault
 public class SemanticTags {
@@ -47,6 +53,9 @@ public class SemanticTags {
 
     private static final Map<String, Class<? extends Tag>> TAGS = new TreeMap<>();
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(SemanticTags.class);
+    private static final SemanticClassLoader CLASS_LOADER = new SemanticClassLoader();
+
     static {
         Locations.stream().forEach(location -> addTagSet(location));
         Equipments.stream().forEach(equipment -> addTagSet(equipment));
@@ -203,6 +212,117 @@ public static String getLabel(Class<? extends Tag> tag, Locale locale) {
         return null;
     }
 
+    /**
+     * Adds a new semantic tag with inferred label, empty synonyms and description.
+     * 
+     * The label will be inferred from the tag name by splitting the CamelCase with a space.
+     * 
+     * @param name the tag name to add
+     * @param parent the parent tag that the new tag should belong to
+     * @return the created semantic tag class, or null if it was already added.
+     */
+    public static @Nullable Class<? extends Tag> add(String name, String parent) {
+        return add(name, parent, null, null, null);
+    }
+
+    /**
+     * Adds a new semantic tag.
+     * 
+     * @param name the tag name to add
+     * @param parent the parent tag that the new tag should belong to
+     * @param label an optional label. When null, the label will be inferred from the tag name,
+     *            splitting the CamelCase with a space.
+     * @param synonyms a comma separated list of synonyms
+     * @param description the tag description
+     * @return the created semantic tag class, or null if it was already added.
+     */
+    public static @Nullable Class<? extends Tag> add(String name, String parent, @Nullable String label,
+            @Nullable String synonyms, @Nullable String description) {
+        Class<? extends Tag> parentClass = getById(parent);
+        if (parentClass == null) {
+            LOGGER.warn("Adding semantic tag '{}' failed because parent tag '{}' is not found.", name, parent);
+            return null;
+        }
+        return add(name, parentClass, label, synonyms, description);
+    }
+
+    /**
+     * Adds a new semantic tag with inferred label, empty synonyms and description.
+     * 
+     * The label will be inferred from the tag name by splitting the CamelCase with a space.
+     * 
+     * @param name the tag name to add
+     * @param parent the parent tag that the new tag should belong to
+     * @return the created semantic tag class, or null if it was already added.
+     */
+    public static @Nullable Class<? extends Tag> add(String name, Class<? extends Tag> parent) {
+        return add(name, parent, null, null, null);
+    }
+
+    /**
+     * Adds a new semantic tag.
+     * 
+     * @param name the tag name to add
+     * @param parent the parent tag that the new tag should belong to
+     * @param label an optional label. When null, the label will be inferred from the tag name,
+     *            splitting the CamelCase with a space.
+     * @param synonyms a comma separated list of synonyms
+     * @param description the tag description
+     * @return the created semantic tag class, or null if it was already added.
+     */
+    public static @Nullable Class<? extends Tag> add(String name, Class<? extends Tag> parent, @Nullable String label,
+            @Nullable String synonyms, @Nullable String description) {
+        if (getById(name) != null) {
+            return null;
+        }
+
+        if (!name.matches("[A-Z][a-zA-Z0-9]+")) {
+            throw new IllegalArgumentException(
+                    "The tag name '" + name + "' must start with a capital letter and contain only alphanumerics.");
+        }
+
+        String parentId = parent.getAnnotation(TagInfo.class).id();
+        String type = parentId.split("_")[0];
+        String className = "org.openhab.core.semantics.model." + type.toLowerCase() + "." + name;
+
+        // Infer label from name, splitting up CamelCaseALL99 -> Camel Case ALL 99
+        label = Optional.ofNullable(label).orElseGet(() -> name.replaceAll("([A-Z][a-z]+|[A-Z][A-Z]+|[0-9]+)", " $1"))
+                .trim();
+        synonyms = Optional.ofNullable(synonyms).orElse("").replaceAll("\\s*,\\s*", ",").trim();
+
+        // Create the tag interface
+        ClassWriter classWriter = new ClassWriter(0);
+        classWriter.visit(Opcodes.V11, Opcodes.ACC_PUBLIC + Opcodes.ACC_ABSTRACT + Opcodes.ACC_INTERFACE,
+                className.replace('.', '/'), null, "java/lang/Object",
+                new String[] { parent.getName().replace('.', '/') });
+
+        // Add TagInfo Annotation
+        classWriter.visitSource("Status.java", null);
+
+        AnnotationVisitor annotation = classWriter.visitAnnotation("Lorg/openhab/core/semantics/TagInfo;", true);
+        annotation.visit("id", parentId + "_" + name);
+        annotation.visit("label", label);
+        annotation.visit("synonyms", synonyms);
+        annotation.visit("description", Optional.ofNullable(description).orElse("").trim());
+        annotation.visitEnd();
+
+        classWriter.visitEnd();
+        byte[] byteCode = classWriter.toByteArray();
+        Class newTag = null;
+        try {
+            newTag = CLASS_LOADER.defineClass(className, byteCode);
+        } catch (Exception e) {
+            LOGGER.warn("Failed creating a new semantic tag '{}': {}", className, e.getMessage());
+            return null;
+        }
+        addToModel(newTag);
+        addTagSet(newTag);
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("'{}' semantic {} tag added.", className, type);
+        }
+        return newTag;
+    }
+
     private static void addTagSet(Class<? extends Tag> tagSet) {
         String id = tagSet.getAnnotation(TagInfo.class).id();
         while (id.indexOf("_") != -1) {
@@ -211,4 +331,28 @@ private static void addTagSet(Class<? extends Tag> tagSet) {
         }
         TAGS.put(id, tagSet);
     }
+
+    private static boolean addToModel(Class<? extends Tag> tag) {
+        if (Location.class.isAssignableFrom(tag)) {
+            return Locations.add((Class<? extends Location>) tag);
+        } else if (Equipment.class.isAssignableFrom(tag)) {
+            return Equipments.add((Class<? extends Equipment>) tag);
+        } else if (Point.class.isAssignableFrom(tag)) {
+            return Points.add((Class<? extends Point>) tag);
+        } else if (Property.class.isAssignableFrom(tag)) {
+            return Properties.add((Class<? extends Property>) tag);
+        }
+        throw new IllegalArgumentException("Unknown type of tag " + tag);
+    }
+
+    private static class SemanticClassLoader extends ClassLoader {
+        public SemanticClassLoader() {
+            super(SemanticTags.class.getClassLoader());
+        }
+
+        public Class<?> defineClass(String className, byte[] byteCode) {
+            // defineClass is protected in the normal ClassLoader
+            return defineClass(className, byteCode, 0, byteCode.length);
+        }
+    }
 }

bundles/org.openhab.core.semantics/src/main/java/org/openhab/core/semantics/model/equipment/Equipments.java

@@ -89,4 +89,8 @@ public class Equipments {
     public static Stream<Class<? extends Equipment>> stream() {
         return EQUIPMENTS.stream();
     }
+
+    public static boolean add(Class<? extends Equipment> tag) {
+        return EQUIPMENTS.add(tag);
+    }
 }

bundles/org.openhab.core.semantics/src/main/java/org/openhab/core/semantics/model/location/Locations.java

@@ -72,4 +72,8 @@ public class Locations {
     public static Stream<Class<? extends Location>> stream() {
         return LOCATIONS.stream();
     }
+
+    public static boolean add(Class<? extends Location> tag) {
+        return LOCATIONS.add(tag);
+    }
 }

bundles/org.openhab.core.semantics/src/main/java/org/openhab/core/semantics/model/point/Points.java

@@ -47,4 +47,8 @@ public class Points {
     public static Stream<Class<? extends Point>> stream() {
         return POINTS.stream();
     }
+
+    public static boolean add(Class<? extends Point> tag) {
+        return POINTS.add(tag);
+    }
 }

bundles/org.openhab.core.semantics/src/main/java/org/openhab/core/semantics/model/property/Properties.java

@@ -63,4 +63,8 @@ public class Properties {
     public static Stream<Class<? extends Property>> stream() {
         return PROPERTIES.stream();
     }
+
+    public static boolean add(Class<? extends Property> tag) {
+        return PROPERTIES.add(tag);
+    }
 }