Add getChildren() signature in FedoraResource...

- Implement it in FedoraResourceImpl.java - Expose the hierarchy levels through the IdentifierConverter and IdentifierTranslator on behalf of the getChildren() implementation. - Integrate the getChildren() method in FedoraResource to generate the hierarchy rdf triples for REST web UI. - Log the potential null children nodes and return as suggested. - Implement FedoraResource.getParent() for transparent hierarchy support. Resolves: https://www.pivotaltracker.com/story/show/71941366
fcrepo · Jul 2, 2014 · ab5139c · ab5139c
1 parent a04bad4
commit ab5139c
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Showing 14 changed files with 262 additions and 10 deletions.
diff --git a/...-http-commons/src/main/java/org/fcrepo/http/commons/api/rdf/HttpIdentifierTranslator.java b/...-http-commons/src/main/java/org/fcrepo/http/commons/api/rdf/HttpIdentifierTranslator.java
@@ -19,6 +19,7 @@
 import com.hp.hpl.jena.rdf.model.Resource;
 
 import org.fcrepo.kernel.exception.RepositoryRuntimeException;
+import org.fcrepo.kernel.identifiers.HierarchyConverter;
 import org.fcrepo.kernel.identifiers.InternalIdentifierConverter;
 import org.fcrepo.kernel.identifiers.NamespaceConverter;
 import org.fcrepo.kernel.services.functions.GetDefaultWorkspace;
@@ -130,6 +131,13 @@ public HttpIdentifierTranslator(final Session session,
         this.defaultWorkspace = getDefaultWorkspace.apply(session.getRepository());
         LOGGER.debug("Resolving graph subjects to a base URI of \"{}\"",
                 normalizedBasePath);
+        resetTranslationChain();
+        for (InternalIdentifierConverter converter : translationChain) {
+            if (converter instanceof HierarchyConverter) {
+                hierarchyLevels = converter.getLevels();
+                break;
+            }
+        }
     }
 
     /**
@@ -317,4 +325,13 @@ protected void resetTranslationChain() {
 
     private static final List<InternalIdentifierConverter> minimalTranslationChain =
         singletonList((InternalIdentifierConverter) new NamespaceConverter());
+
+    /**
+     * Hierarchy levels. Default 1 for converters other than the HierarchyConverter.
+     * @return
+     */
+    @Override
+    public int getHierarchyLevels() {
+        return hierarchyLevels;
+    }
 }
diff --git a/...p-commons/src/test/java/org/fcrepo/http/commons/api/rdf/HttpIdentifierTranslatorTest.java b/...p-commons/src/test/java/org/fcrepo/http/commons/api/rdf/HttpIdentifierTranslatorTest.java
@@ -232,6 +232,11 @@ protected static UriInfo getUriInfoImpl(final String path) {
         return ui;
     }
 
+    @Test
+    public void testGetHierarchyLevels() {
+        assertTrue(testObj.getHierarchyLevels() >= 0);
+    }
+
     @Path("/rest/{path}")
     protected class MockNodeController {
 

diff --git a/fcrepo-kernel-api/src/main/java/org/fcrepo/kernel/FedoraResource.java b/fcrepo-kernel-api/src/main/java/org/fcrepo/kernel/FedoraResource.java
@@ -17,7 +17,7 @@
 
 import java.util.Collection;
 import java.util.Date;
-
+import java.util.Iterator;
 import javax.jcr.Node;
 import javax.jcr.RepositoryException;
 import javax.jcr.version.Version;
@@ -137,6 +137,25 @@ RdfStream getHierarchyTriples(final IdentifierTranslator graphSubjects,
                                   final HierarchyRdfContextOptions serializationOptions)
         throws RepositoryException;
 
+    /**
+     * Return a list children of this object
+     * @param graphSubjects
+     * @return
+     * @throws RepositoryException
+     */
+    Iterator<Node> getChildren(final IdentifierTranslator graphSubjects)
+        throws RepositoryException;
+
+    /**
+     * Return the parent node of this object
+     * @param graphSubjects
+     * @return
+     * @throws RepositoryException
+     */
+    Node getParent(final IdentifierTranslator graphSubjects)
+        throws RepositoryException;
+
+
     /**
      * Serialize the JCR versions information as an RDF dataset
      * @param graphSubjects
@@ -165,7 +184,7 @@ RdfStream getVersionTriples(final IdentifierTranslator graphSubjects)
 
     /**
      * Get the JCR Base version for the node
-     * 
+     *
      * @return base version
      * @throws RepositoryException
      */

diff --git a/fcrepo-kernel-api/src/main/java/org/fcrepo/kernel/identifiers/IdentifierConverter.java b/fcrepo-kernel-api/src/main/java/org/fcrepo/kernel/identifiers/IdentifierConverter.java
@@ -27,5 +27,13 @@
  * @param <T> the type to and from which we are translating
  */
 public abstract class IdentifierConverter<T> extends Converter<String, T> {
+    protected int hierarchyLevels = 0;
 
+    /**
+     * Get hierarchy levels for path conversion
+     * @return
+     **/
+    public int getLevels() {
+        return hierarchyLevels;
+    }
 }
diff --git a/fcrepo-kernel-api/src/main/java/org/fcrepo/kernel/rdf/IdentifierTranslator.java b/fcrepo-kernel-api/src/main/java/org/fcrepo/kernel/rdf/IdentifierTranslator.java
@@ -57,4 +57,10 @@ public interface IdentifierTranslator {
      * @return Resource
      */
     Resource getContext();
+
+    /**
+     * Get the hierarchy levels for translation
+     * @return
+     */
+    int getHierarchyLevels();
 }
diff --git a/...nel-api/src/test/java/org/fcrepo/kernel/identifiers/ExternalIdentifierTranslatorTest.java b/...nel-api/src/test/java/org/fcrepo/kernel/identifiers/ExternalIdentifierTranslatorTest.java
@@ -18,6 +18,7 @@
 import static java.util.Collections.singletonList;
 import static org.fcrepo.kernel.identifiers.InternalIdentifierConverter.identityConverter;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 
 import org.junit.Before;
 import org.junit.Test;
@@ -37,6 +38,11 @@ public void setUp() {
         testTranslator = new ExternalIdentifierConverter();
     }
 
+    @Test
+    public void testGetHierarchyLevels() {
+        assertTrue(testTranslator.getLevels() >= 0);
+    }
+
     @Test
     public void testRoundTrip() {
         testTranslator.setTranslationChain(singletonList(identityConverter()));

diff --git a/fcrepo-kernel/src/main/java/org/fcrepo/kernel/FedoraResourceImpl.java b/fcrepo-kernel/src/main/java/org/fcrepo/kernel/FedoraResourceImpl.java
@@ -31,16 +31,23 @@
 import static org.fcrepo.kernel.utils.FedoraTypesUtils.nodetype2name;
 import static org.fcrepo.kernel.utils.FedoraTypesUtils.property2values;
 import static org.fcrepo.kernel.utils.FedoraTypesUtils.value2string;
+import static org.fcrepo.kernel.utils.FedoraTypesUtils.isInternalNode;
 import static org.modeshape.jcr.api.JcrConstants.JCR_CONTENT;
 import static org.modeshape.jcr.api.JcrConstants.NT_FOLDER;
 import static org.slf4j.LoggerFactory.getLogger;
 
+import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.Collection;
 import java.util.Date;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
 import java.util.Set;
+import java.util.TreeMap;
 
 import javax.jcr.Node;
+import javax.jcr.NodeIterator;
 import javax.jcr.RepositoryException;
 import javax.jcr.Session;
 import javax.jcr.version.Version;
@@ -386,4 +393,99 @@ public String getEtagValue() throws RepositoryException {
         }
         return "";
     }
+
+    @Override
+    public Iterator<Node> getChildren(final IdentifierTranslator graphSubjects) throws RepositoryException {
+        return getChildren(node, graphSubjects);
+    }
+
+    /**
+     * Retrieve children of a node
+     * @param node
+     * @param graphSubjects
+     * @return
+     * @throws RepositoryException
+     */
+    public static Iterator<Node> getChildren(final Node node, final IdentifierTranslator graphSubjects)
+            throws RepositoryException {
+        final int hierarchyLevels = graphSubjects.getHierarchyLevels();
+        return findChildren(node, hierarchyLevels);
+    }
+
+    /**
+     * Find the child resources of a path.
+     * @param recurse If true, find all descenant resources, not just direct children.
+     * @throws RepositoryException
+    **/
+    private static Iterator<Node> findChildren(final Node node, final int hierarchyLevels) throws RepositoryException {
+        final Map<String, Node> childrenMap = new TreeMap<>();
+        final List<Node> children = new ArrayList<>();
+        findChildren( node, children, false );
+        for (int i = 0; i < hierarchyLevels && children.size() > 0; i++) {
+            final List<Node> childrenCopy = new ArrayList<>();
+            childrenCopy.addAll(children);
+            children.clear();
+            for (final Node child : childrenCopy) {
+                findChildren( child, children, false );
+            }
+        }
+
+        for (final Node child : children) {
+            childrenMap.put(child.getPath(), child);
+        }
+        return childrenMap.values().iterator();
+    }
+
+    /**
+     * Find children of a node.
+     * @param node Repository node to find children of
+     * @param children Set to add child paths to
+     * @param If true, find all descendant paths, not just direct child paths
+    **/
+    private static void findChildren(final Node node, final List<Node> children, final boolean recurse)
+        throws RepositoryException {
+        if (node.getNodes() == null) {
+            LOGGER.debug("Null children nodes returned from {}", node.getPath());
+            return;
+        }
+        for (final NodeIterator nodes = node.getNodes(); nodes.hasNext();) {
+            final Node child = nodes.nextNode();
+            if (!isInternalNode.apply(child) && !child.getName().equals(JCR_CONTENT)) {
+
+                children.add(child);
+
+                if (recurse) {
+                    findChildren(child, children, recurse);
+                }
+            }
+        }
+    }
+
+    /**
+     * Get the parent of the current node
+     * @param graphSubjects
+     * @return
+     * @throws RepositoryException
+     */
+    @Override
+    public Node getParent(final IdentifierTranslator graphSubjects) throws RepositoryException {
+        return findParent(node, graphSubjects);
+    }
+
+    /**
+     * Find the parent of the node
+     * @param node
+     * @param graphSubjects
+     * @return
+     * @throws RepositoryException
+     */
+    public static Node findParent(final Node node, final IdentifierTranslator graphSubjects)
+            throws RepositoryException {
+        final int hierarchyLevels = graphSubjects.getHierarchyLevels();
+        Node parent = node.getParent();
+        for (int i = 0; i < hierarchyLevels; i++) {
+            parent = parent.getParent();
+        }
+        return parent;
+    }
 }
diff --git a/fcrepo-kernel/src/main/java/org/fcrepo/kernel/identifiers/HierarchyConverter.java b/fcrepo-kernel/src/main/java/org/fcrepo/kernel/identifiers/HierarchyConverter.java
@@ -288,4 +288,12 @@ public String convertNamespace(final String namespace) {
             return namespace;
         }
     }
+
+    /**
+     * Get hierarchy levels
+     */
+    @Override
+    public int getLevels() {
+        return levels;
+    }
 }
diff --git a/fcrepo-kernel/src/main/java/org/fcrepo/kernel/rdf/impl/DefaultIdentifierTranslator.java b/fcrepo-kernel/src/main/java/org/fcrepo/kernel/rdf/impl/DefaultIdentifierTranslator.java
@@ -85,4 +85,9 @@ public boolean isFedoraGraphSubject(final Resource subject) {
         return subject.isURIResource() && subject.getURI().startsWith(RESOURCE_NAMESPACE);
     }
 
+    @Override
+    public int getHierarchyLevels() {
+        return 0;
+    }
+
 }
diff --git a/fcrepo-kernel/src/main/java/org/fcrepo/kernel/rdf/impl/HierarchyRdfContext.java b/fcrepo-kernel/src/main/java/org/fcrepo/kernel/rdf/impl/HierarchyRdfContext.java
@@ -15,7 +15,6 @@
  */
 package org.fcrepo.kernel.rdf.impl;
 
-import static com.google.common.base.Predicates.not;
 import static com.google.common.base.Throwables.propagate;
 import static com.hp.hpl.jena.graph.Triple.create;
 import static com.hp.hpl.jena.vocabulary.RDF.type;
@@ -37,7 +36,7 @@
 import org.fcrepo.kernel.rdf.HierarchyRdfContextOptions;
 import org.fcrepo.kernel.rdf.IdentifierTranslator;
 import org.fcrepo.kernel.rdf.JcrRdfTools;
-import org.fcrepo.kernel.utils.iterators.NodeIterator;
+import org.fcrepo.kernel.FedoraResourceImpl;
 import org.fcrepo.kernel.utils.iterators.RdfStream;
 import org.slf4j.Logger;
 
@@ -106,7 +105,7 @@ private Triple[] containerContext() {
     }
 
     private Iterator<Triple> parentContext() throws RepositoryException {
-        final javax.jcr.Node parentNode = node().getParent();
+        final javax.jcr.Node parentNode = FedoraResourceImpl.findParent(node(), graphSubjects());//node().getParent();
         final Node parentNodeSubject = graphSubjects().getSubject(parentNode.getPath()).asNode();
 
         final RdfStream parentStream = new RdfStream();
@@ -117,9 +116,8 @@ private Iterator<Triple> parentContext() throws RepositoryException {
     }
 
     private Iterator<Triple> childrenContext() throws RepositoryException {
-
-        final Iterator<javax.jcr.Node> niceChildren =
-            Iterators.filter(new NodeIterator(node().getNodes()), not(nastyChildren));
+        final Iterator<javax.jcr.Node> niceChildren = FedoraResourceImpl.getChildren(node(), graphSubjects());
+            //Iterators.filter(new NodeIterator(node().getNodes()), not(nastyChildren));
 
         final Iterator<javax.jcr.Node> salientChildren;