Added API to return a list of indexed fields. Output is JSON.

repository/src/main/java/org/apache/hadoop/metadata/discovery/DiscoveryService.java

@@ -24,6 +24,7 @@ import org.codehaus.jettison.json.JSONObject;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 /**
  * Metadata discovery service.
@@ -54,4 +55,9 @@ public interface DiscoveryService {
      */
     Map<String, HashMap<String,JSONObject>> relationshipWalk(String guid, int depth, String edgesToFollow);
 
+    /**
+     * Return a Set of indexed properties in the graph.
+     * No parameters.
+     */
+    Set<String> getGraphIndexedFields();
 }

repository/src/main/java/org/apache/hadoop/metadata/discovery/GraphBackedDiscoveryService.java

@@ -29,6 +29,7 @@ import javax.inject.Inject;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 public class GraphBackedDiscoveryService implements DiscoveryService {
 
@@ -81,5 +82,14 @@ public class GraphBackedDiscoveryService implements DiscoveryService {
     	
     }
     
+    /**
+     * Return a Set of indexed properties in the graph.
+     * No parameters.
+     */
+    @Override
+    public Set<String> getGraphIndexedFields() {
+    	return repository.getGraphIndexedFields();
+    }
+    
     
 }

repository/src/main/java/org/apache/hadoop/metadata/repository/MetadataRepository.java

@@ -28,6 +28,7 @@ import org.codehaus.jettison.json.JSONObject;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 /**
  * An interface for persisting metadata into a blueprints enabled graph db.
@@ -64,4 +65,10 @@ public interface MetadataRepository extends Service {
      * @param edgesToFollow is a comma-separated-list of edges to follow.
      */
     Map<String, HashMap<String,JSONObject>> relationshipWalk(String guid, int depth, String edgesToFollow);
+       
+    /**
+     * Return a Set of indexed properties in the graph.
+     * No parameters.
+     */
+    Set<String> getGraphIndexedFields();
 }

repository/src/main/java/org/apache/hadoop/metadata/repository/graph/GraphBackedMetadataRepository.java

@@ -65,6 +65,7 @@ import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /**
@@ -142,6 +143,15 @@ public class GraphBackedMetadataRepository implements MetadataRepository {
         }
     }
     
+    /**
+     * Return a Set of indexed properties in the graph.
+     * No parameters.
+     */
+    @Override
+    public Set<String> getGraphIndexedFields() {
+    	return graphService.getIndexableGraph().getIndexedKeys(Vertex.class);
+    }
+
     @Override
     public ITypedReferenceableInstance getEntityDefinition(String guid) throws RepositoryException {
         LOG.info("Retrieving entity with guid={}", guid);

webapp/src/main/java/org/apache/hadoop/metadata/web/resources/MetadataDiscoveryResource.java

@@ -190,4 +190,31 @@ public class MetadataDiscoveryResource {
 
     }
     
+    /**
+     * Return a list Vertices and Edges in the index.
+     * 
+     * GET http://host/api/metadata/discovery/getIndexedFields
+     *
+     * No parameters taken.
+     */    
+  
+    @GET
+    @Path("/getIndexedFields")
+    @Produces({MediaType.APPLICATION_JSON})
+    public Response getLineageResults() {
+    	
+    	JSONObject response = new JSONObject();
+    	
+    	try {
+    		response.put("indexed_fields:",discoveryService.getGraphIndexedFields());
+    	} catch (JSONException e) {
+   			throw new WebApplicationException(
+                    Servlets.getErrorResponse("Search: Error building JSON result set.", Response.Status.INTERNAL_SERVER_ERROR));
+   		}
+    	
+    	LOG.debug("JSON result:" + response.toString());
+       	return Response.ok(response).build();
+    	
+    }
+
 }

webapp/src/test/java/org/apache/hadoop/metadata/web/resources/MetadataDiscoveryResourceIT.java

@@ -46,6 +46,19 @@ public class MetadataDiscoveryResourceIT extends BaseResourceIT {
     }
     
     @Test
+    public void testGetIndexedProperties() throws Exception {
+        WebResource resource = service
+                .path("api/metadata/discovery/getIndexedFields");
+
+        ClientResponse clientResponse = resource
+                .accept(MediaType.APPLICATION_JSON)
+                .type(MediaType.APPLICATION_JSON)
+                .method(HttpMethod.GET, ClientResponse.class);
+        Assert.assertNotEquals(clientResponse.getStatus(), Response.Status.NOT_FOUND.getStatusCode());
+        
+    }
+    
+    @Test
     public void testLineageUriExists() throws Exception {
         WebResource resource = service
                 .path("api/metadata/discovery/search/relationships/1")