mint etags for all fedora resources and use them for conditional requ…

…ests.
fcrepo · Jul 29, 2013 · 8b3be13 · 8b3be13
1 parent dc01984
commit 8b3be13
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Showing 6 changed files with 75 additions and 10 deletions.
diff --git a/fcrepo-http-api/src/main/java/org/fcrepo/api/FedoraNodes.java b/fcrepo-http-api/src/main/java/org/fcrepo/api/FedoraNodes.java
@@ -64,6 +64,7 @@
 import javax.ws.rs.WebApplicationException;
 import javax.ws.rs.core.CacheControl;
 import javax.ws.rs.core.Context;
+import javax.ws.rs.core.EntityTag;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.PathSegment;
 import javax.ws.rs.core.Request;
@@ -134,13 +135,15 @@ public Dataset describe(@PathParam("path") final List<PathSegment> pathList,
             final FedoraResource resource =
                     nodeService.getObject(session, path);
 
+
+            final EntityTag etag = new EntityTag(resource.getEtagValue());
             final Date date = resource.getLastModifiedDate();
             final Date roundedDate = new Date();
             if (date != null) {
                 roundedDate.setTime(date.getTime() - date.getTime() % 1000);
             }
             final ResponseBuilder builder =
-                    request.evaluatePreconditions(roundedDate);
+                    request.evaluatePreconditions(roundedDate, etag);
             if (builder != null) {
                 final CacheControl cc = new CacheControl();
                 cc.setMaxAge(0);
@@ -149,7 +152,7 @@ public Dataset describe(@PathParam("path") final List<PathSegment> pathList,
                 // the exception is not an error, it's genuinely
                 // an exceptional condition
                 throw new WebApplicationException(builder.cacheControl(cc)
-                        .lastModified(date).build());
+                        .lastModified(date).tag(etag).build());
             }
             final HttpGraphSubjects subjects =
                     new HttpGraphSubjects(session, FedoraNodes.class, uriInfo);
@@ -201,6 +204,10 @@ public Dataset describe(@PathParam("path") final List<PathSegment> pathList,
 
             }
 
+            if (!etag.getValue().isEmpty()) {
+                servletResponse.addHeader("ETag", etag.toString());
+            }
+
             servletResponse.addHeader("Accept-Patch", WebContent.contentTypeSPARQLUpdate);
             servletResponse.addHeader("Link", "http://www.w3.org/ns/ldp/Resource;rel=\"type\"");
 
@@ -267,6 +274,7 @@ public Response updateSparql(@PathParam("path")
                         nodeService.getObject(session, path);
 
 
+                final EntityTag etag = new EntityTag(resource.getEtagValue());
                 final Date date = resource.getLastModifiedDate();
                 final Date roundedDate = new Date();
 
@@ -275,7 +283,7 @@ public Response updateSparql(@PathParam("path")
                 }
 
                 final ResponseBuilder builder =
-                    request.evaluatePreconditions(roundedDate);
+                    request.evaluatePreconditions(roundedDate, etag);
 
                 if (builder != null) {
                     throw new WebApplicationException(builder.build());
@@ -335,12 +343,15 @@ public Response createOrReplaceObjectRdf(
             final Date date = resource.getLastModifiedDate();
             final Date roundedDate = new Date();
 
+
+            final EntityTag etag = new EntityTag(resource.getEtagValue());
+
             if (date != null) {
                 roundedDate.setTime(date.getTime() - date.getTime() % 1000);
             }
 
             final ResponseBuilder builder =
-                request.evaluatePreconditions(roundedDate);
+                request.evaluatePreconditions(roundedDate, etag);
 
             if (builder != null) {
                 throw new WebApplicationException(builder.build());

diff --git a/fcrepo-http-api/src/test/java/org/fcrepo/api/FedoraNodesTest.java b/fcrepo-http-api/src/test/java/org/fcrepo/api/FedoraNodesTest.java
@@ -207,7 +207,7 @@ public void testDescribeObject() throws RepositoryException, IOException {
         when(mockDataset.getDefaultModel()).thenReturn(mockModel);
         when(mockDataset.getContext()).thenReturn(mockContext);
 
-        when(mockObject.getLastModifiedDate()).thenReturn(null);
+        when(mockObject.getEtagValue()).thenReturn("");
         when(
                 mockObject.getPropertiesDataset(any(GraphSubjects.class),
                         anyLong(), anyInt())).thenReturn(mockDataset);
@@ -230,7 +230,7 @@ public void testDescribeObjectNoInlining() throws RepositoryException, IOExcepti
         when(mockDataset.getDefaultModel()).thenReturn(mockModel);
         when(mockDataset.getContext()).thenReturn(mockContext);
 
-        when(mockObject.getLastModifiedDate()).thenReturn(null);
+        when(mockObject.getEtagValue()).thenReturn("");
         when(
                 mockObject.getPropertiesDataset(any(GraphSubjects.class),
                                                    anyLong(), eq(-2))).thenReturn(mockDataset);
@@ -252,7 +252,8 @@ public void testSparqlUpdate() throws RepositoryException, IOException {
                 new ByteArrayInputStream("my-sparql-statement".getBytes());
         when(mockNodes.getObject(mockSession, path)).thenReturn(mockObject);
         when(mockObject.updatePropertiesDataset(any(GraphSubjects.class), any(String.class)))
-        .thenReturn(mockDataset);
+            .thenReturn(mockDataset);
+        when(mockObject.getEtagValue()).thenReturn("");
 
         when(mockObject.getLastModifiedDate()).thenReturn(Calendar.getInstance().getTime());
         when(mockDataset.getNamedModel(GraphProperties.PROBLEMS_MODEL_NAME))
@@ -271,6 +272,7 @@ public void testReplaceRdf() throws RepositoryException, IOException, URISyntaxE
         final String path = "/" + pid;
         when(mockObject.getLastModifiedDate()).thenReturn(Calendar.getInstance().getTime());
         when(mockObject.getNode()).thenReturn(mockNode);
+        when(mockObject.getEtagValue()).thenReturn("");
         when(mockNode.getPath()).thenReturn(path);
 
         final InputStream mockStream =

diff --git a/fcrepo-http-api/src/test/java/org/fcrepo/integration/api/FedoraNodesIT.java b/fcrepo-http-api/src/test/java/org/fcrepo/integration/api/FedoraNodesIT.java
@@ -575,8 +575,10 @@ public void testDescribeRdfCached() throws RepositoryException, IOException {
                 .getStatusLine().getStatusCode());
         final String lastModed =
                 response.getFirstHeader("Last-Modified").getValue();
+        final String etag = response.getFirstHeader("ETag").getValue();
         final HttpGet getObjMethod2 = new HttpGet(serverAddress + path);
         getObjMethod2.setHeader("If-Modified-Since", lastModed);
+        getObjMethod2.setHeader("If-None-Match", etag);
         response = specialClient.execute(getObjMethod2);
 
         assertEquals("Client didn't return a NOT_MODIFIED!", NOT_MODIFIED

diff --git a/fcrepo-kernel/src/main/java/org/fcrepo/FedoraResource.java b/fcrepo-kernel/src/main/java/org/fcrepo/FedoraResource.java
@@ -34,6 +34,7 @@
 
 import com.hp.hpl.jena.update.UpdateFactory;
 import com.hp.hpl.jena.update.UpdateRequest;
+import org.apache.commons.codec.digest.DigestUtils;
 import org.fcrepo.rdf.GraphProperties;
 import org.fcrepo.rdf.GraphSubjects;
 import org.fcrepo.rdf.impl.JcrGraphProperties;
@@ -317,4 +318,25 @@ public Dataset replacePropertiesDataset(final GraphSubjects subjects, final Mode
 
         return propertiesDataset;
     }
+
+    /**
+     * Construct an ETag value from the last modified date and path.
+     *
+     * JCR has a mix:etag type, but it only takes into account binary
+     * properties. We actually want whole-object etag data.
+     *
+     * TODO : construct and store an ETag value on object modify
+     *
+     * @return
+     * @throws RepositoryException
+     */
+    public String getEtagValue() throws RepositoryException {
+        final Date lastModifiedDate = getLastModifiedDate();
+
+        if (lastModifiedDate != null) {
+            return DigestUtils.shaHex(node.getPath() + lastModifiedDate.toString());
+        } else {
+            return "";
+        }
+    }
 }
diff --git a/fcrepo-kernel/src/test/java/org/fcrepo/FedoraResourceTest.java b/fcrepo-kernel/src/test/java/org/fcrepo/FedoraResourceTest.java
@@ -49,6 +49,7 @@
 import javax.jcr.version.VersionHistory;
 
 import com.hp.hpl.jena.rdf.model.ModelFactory;
+import org.apache.commons.codec.digest.DigestUtils;
 import org.fcrepo.rdf.GraphSubjects;
 import org.fcrepo.rdf.impl.DefaultGraphSubjects;
 import org.fcrepo.utils.FedoraTypesUtils;
@@ -358,5 +359,17 @@ public void testReplacePropertiesDataset() throws RepositoryException {
                                               propertiesModel.createProperty("y"),
                                               "z"));
     }
+    @Test
+    public void shouldGetEtagForAnObject() throws RepositoryException {
+        final Property mockMod = mock(Property.class);
+        final Calendar modDate = Calendar.getInstance();
+        modDate.set(2013, Calendar.JULY, 30, 0, 0, 0);
+        when(mockNode.getPath()).thenReturn("some-path");
+        when(mockNode.hasProperty(JCR_LASTMODIFIED)).thenReturn(true);
+        when(mockNode.getProperty(JCR_LASTMODIFIED)).thenReturn(mockMod);
+        when(mockMod.getDate()).thenReturn(modDate);
+
+        assertEquals(DigestUtils.shaHex("some-path" + testObj.getLastModifiedDate().toString()), testObj.getEtagValue());
+    }
 
 }
diff --git a/fcrepo-kernel/src/test/java/org/fcrepo/integration/FedoraResourceIT.java b/fcrepo-kernel/src/test/java/org/fcrepo/integration/FedoraResourceIT.java
@@ -17,9 +17,11 @@
 
 import static com.hp.hpl.jena.graph.NodeFactory.createLiteral;
 import static com.hp.hpl.jena.graph.NodeFactory.createURI;
+import static junit.framework.Assert.assertNotNull;
 import static org.fcrepo.utils.FedoraTypesUtils.getVersionHistory;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertTrue;
 
 import java.io.ByteArrayInputStream;
@@ -43,6 +45,7 @@
 import org.fcrepo.services.DatastreamService;
 import org.fcrepo.services.NodeService;
 import org.fcrepo.services.ObjectService;
+import org.fcrepo.utils.FedoraJcrTypes;
 import org.fcrepo.utils.JcrRdfTools;
 import org.junit.After;
 import org.junit.Before;
@@ -396,9 +399,9 @@ public void testUpdatingRdfTypedValues() throws RepositoryException {
         logger.warn(propertiesDataset.toString());
 
         object.updatePropertiesDataset(subjects, "PREFIX example: <http://example.org/>\n" +
-                                                 "PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>\n" +
-                                          "INSERT { <info:fedora/testObjectRdfType> example:int-property \"0\"^^xsd:long } WHERE { }");
-        assertEquals(PropertyType.LONG,  object.getNode().getProperty("example:int-property").getType());
+                                                     "PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>\n" +
+                                                     "INSERT { <info:fedora/testObjectRdfType> example:int-property \"0\"^^xsd:long } WHERE { }");
+        assertEquals(PropertyType.LONG, object.getNode().getProperty("example:int-property").getType());
         assertEquals(0L, object.getNode().getProperty("example:int-property").getValues()[0].getLong());
     }
 
@@ -417,4 +420,16 @@ public void testUpdatingRdfType() throws RepositoryException {
         assertEquals(PropertyType.URI,  object.getNode().getProperty("rdf:type").getType());
         assertEquals("http://some/uri", object.getNode().getProperty("rdf:type").getValues()[0].getString());
     }
+
+    @Test
+    public void testEtagValue() throws RepositoryException {
+        final FedoraResource object =
+            objectService.createObject(session, "/testEtagObject");
+
+        session.save();
+
+        final String actual = object.getEtagValue();
+        assertNotNull(actual);
+        assertNotEquals("", actual);
+    }
 }