support templates for RegisteredType instances, using tags

Author: ahgittin

api/src/main/java/org/apache/brooklyn/api/objs/BrooklynObjectType.java

@@ -95,6 +95,7 @@ public static BrooklynObjectType of(Class<?> objectTypeOrSpecType) {
     }
 
     public static BrooklynObjectType of(CatalogItemType t) {
+        if (t==null) return null;
         switch (t) {
         case ENRICHER: return BrooklynObjectType.ENRICHER;
         case ENTITY: return BrooklynObjectType.ENTITY;

api/src/main/java/org/apache/brooklyn/api/typereg/BrooklynTypeRegistry.java

@@ -38,7 +38,9 @@ public enum RegisteredTypeKind {
         /** a registered type which will create the java type described */
         BEAN,
         /** a partially registered type which requires subsequent validation and changing the kind;
-         * until then, an item of this kind cannot be instantiated */
+         * until then, an item of this kind cannot be instantiated.
+         * items registered as templates (using a tag) may remain in this state
+         * if they do not resolve. */
         UNRESOLVED
         // note: additional kinds should have the visitor in core/RegisteredTypeKindVisitor updated
         // to flush out all places which want to implement support for all kinds 

core/src/main/java/org/apache/brooklyn/core/catalog/internal/BasicBrooklynCatalog.java

@@ -43,9 +43,8 @@
 import org.apache.brooklyn.api.catalog.CatalogItem;
 import org.apache.brooklyn.api.catalog.CatalogItem.CatalogBundle;
 import org.apache.brooklyn.api.catalog.CatalogItem.CatalogItemType;
+import org.apache.brooklyn.api.entity.Application;
 import org.apache.brooklyn.api.internal.AbstractBrooklynObjectSpec;
-import org.apache.brooklyn.api.location.Location;
-import org.apache.brooklyn.api.location.LocationSpec;
 import org.apache.brooklyn.api.mgmt.ManagementContext;
 import org.apache.brooklyn.api.mgmt.classloading.BrooklynClassLoadingContext;
 import org.apache.brooklyn.api.objs.BrooklynObject;
@@ -56,7 +55,7 @@
 import org.apache.brooklyn.api.typereg.RegisteredType;
 import org.apache.brooklyn.core.catalog.CatalogPredicates;
 import org.apache.brooklyn.core.catalog.internal.CatalogClasspathDo.CatalogScanningModes;
-import org.apache.brooklyn.core.location.BasicLocationRegistry;
+import org.apache.brooklyn.core.mgmt.BrooklynTags;
 import org.apache.brooklyn.core.mgmt.ha.OsgiBundleInstallationResult;
 import org.apache.brooklyn.core.mgmt.ha.OsgiManager;
 import org.apache.brooklyn.core.mgmt.internal.CampYamlParser;
@@ -869,22 +868,34 @@ private void collectCatalogItemsFromItemMetadataBlock(String sourceYaml, Managed
             // just need TODO to make sure we delete previously-persisted things which now come through this path.)  
             // NB: when everything is a bundle and we've removed all scanning then this can be the _only_ path
             // and code can be massively simpler
+            // TODO allow these to be set in catalog.bom ?
+            List<String> aliases = MutableList.of();
+            List<Object> tags = MutableList.of();
+            Boolean catalogDisabled = null;
+            
+            MutableList<Object> superTypes = MutableList.of();
+
+            if (itemType==CatalogItemType.TEMPLATE) {
+                tags.add(BrooklynTags.CATALOG_TEMPLATE);
+                itemType = CatalogItemType.ENTITY;
+                superTypes.add(Application.class);
+            }
 
             if (resolutionError!=null) {
-                if (requireValidation) {
-                    throw Exceptions.propagate(resolutionError);
+                if (!tags.contains(BrooklynTags.CATALOG_TEMPLATE)) {
+                    if (requireValidation) {
+                        throw Exceptions.propagate(resolutionError);
+                    }
+                    // warn? add as "unresolved" ? just do nothing?
                 }
-                // warn? add as "unresolved" ? just do nothing?
             }
-            String format = null; // could support specifying format
-            // TODO if kind and supertype is known, set those here
-            Class<?> javaType = null;
-            List<Object> superTypes = MutableList.of().appendIfNotNull(javaType);
+            String format = null; // could support specifying format?
 
-            // TODO allow these to be set in catalog.bom ?
-            List<String> aliases = MutableList.of();
-            List<Object> tags = MutableList.of();
-            Boolean catalogDisabled = null;
+            if (itemType!=null) {
+                // if supertype is known, set it here;
+                // we don't set kind (spec) because that is inferred from the supertype type
+                superTypes.appendIfNotNull(BrooklynObjectType.of(itemType).getInterfaceType());
+            }
 
             if (version==null) {
                 // use this as default version when nothing specified
@@ -1447,6 +1458,10 @@ public Map<RegisteredType,Collection<Throwable>> validateTypes(Iterable<Register
     public Collection<Throwable> validateType(RegisteredType typeToValidate) {
         ReferenceWithError<RegisteredType> result = resolve(typeToValidate);
         if (result.hasError()) {
+            if (RegisteredTypes.isTemplate(typeToValidate)) {
+                // ignore for templates
+                return Collections.emptySet();
+            }
             if (result.getError() instanceof CompoundRuntimeException) {
                 return ((CompoundRuntimeException)result.getError()).getAllCauses();
             }
@@ -1456,7 +1471,7 @@ public Collection<Throwable> validateType(RegisteredType typeToValidate) {
         ((BasicBrooklynTypeRegistry) mgmt.getTypeRegistry()).addToLocalUnpersistedTypeRegistry(result.get(), true);
         return Collections.emptySet();
     }
-    
+
     /** 
      * Resolves the given object with respect to the catalog. Returns any errors found while trying to resolve. 
      * The argument may be changed (e.g. its kind set, supertypes set), and normal usage is to add 

core/src/main/java/org/apache/brooklyn/core/mgmt/BrooklynTags.java

@@ -39,6 +39,9 @@ public class BrooklynTags {
     public static final String NOTES_KIND = "notes";
     public static final String OWNER_ENTITY_ID = "owner_entity_id";
     public static final String ICON_URL = "icon_url";
+    /** tag on a registered type indicating that an item is intended to be used as a template,
+     * and does not have to resolve */
+    public static final Object CATALOG_TEMPLATE = "catalog_template";
 
     public static class NamedStringTag implements Serializable {
         private static final long serialVersionUID = 7932098757009051348L;

core/src/main/java/org/apache/brooklyn/core/typereg/RegisteredTypes.java

@@ -584,4 +584,9 @@ public static RegisteredType changePlan(RegisteredType type, TypeImplementationP
         return type;
     }
 
+    public static boolean isTemplate(RegisteredType type) {
+        if (type==null) return false;
+        return type.getTags().contains(BrooklynTags.CATALOG_TEMPLATE);
+    }
+
 }