improve ChangesetViewer api

scm-core/src/main/java/sonia/scm/repository/RepositoryHandler.java

@@ -69,6 +69,9 @@ public interface RepositoryHandler
    *
    * @param repository
    * @return null if ChangesetViewer is not supported
+   *
+   * @throws RepositoryException
    */
-  public ChangesetViewer getChangesetViewer(Repository repository);
+  public ChangesetViewer getChangesetViewer(Repository repository)
+          throws RepositoryException;
 }

scm-core/src/main/java/sonia/scm/repository/RepositoryManager.java

@@ -63,6 +63,19 @@ public interface RepositoryManager
    */
   public Repository get(String type, String name);
 
+  /**
+   * Method description
+   *
+   *
+   *
+   * @param repository
+   * @return null if ChangesetViewer is not supported
+   *
+   * @throws RepositoryException
+   */
+  public ChangesetViewer getChangesetViewer(Repository repository)
+          throws RepositoryException;
+
   /**
    * Method description
    *

scm-webapp/src/main/java/sonia/scm/api/rest/resources/RepositoryResource.java

@@ -120,6 +120,8 @@ public class RepositoryResource
    * @param max
    *
    * @return
+   *
+   * @throws RepositoryException
    */
   @GET
   @Path("{id}/changesets")
@@ -127,41 +129,31 @@ public class RepositoryResource
   public Response getChangesets(@PathParam("id") String id,
                                 @QueryParam("changeset") String startId,
                                 @DefaultValue("25") @QueryParam("max") int max)
+                                throws RepositoryException
   {
     Response response = null;
     Repository repository = repositoryManager.get(id);
 
     if (repository != null)
     {
-      RepositoryHandler handler =
+      ChangesetViewer changesetViewer =
-        repositoryManager.getHandler(repository.getType());
+        repositoryManager.getChangesetViewer(repository);
 
-      if (handler != null)
+      if (changesetViewer != null)
       {
-        ChangesetViewer changesetViewer =
+        List<Changeset> changesets = null;
-          handler.getChangesetViewer(repository);
 
-        if (changesetViewer != null)
+        if (Util.isNotEmpty(startId))
         {
-          List<Changeset> changesets = null;
+          changesets = changesetViewer.getChangesets(startId, max);
-
-          if (Util.isNotEmpty(startId))
-          {
-            changesets = changesetViewer.getChangesets(startId, max);
-          }
-          else
-          {
-            changesets = changesetViewer.getLastChangesets(max);
-          }
-
-          response =
-            Response.ok(new GenericEntity<List<Changeset>>(changesets) {}
-          ).build();
         }
         else
         {
-          response = Response.status(Response.Status.NOT_FOUND).build();
+          changesets = changesetViewer.getLastChangesets(max);
         }
+
+        response = Response.ok(new GenericEntity<List<Changeset>>(changesets) {}
+        ).build();
       }
       else
       {

scm-webapp/src/main/java/sonia/scm/repository/xml/XmlRepositoryManager.java

@@ -47,6 +47,7 @@ import sonia.scm.HandlerEvent;
 import sonia.scm.SCMContextProvider;
 import sonia.scm.Type;
 import sonia.scm.repository.AbstractRepositoryManager;
+import sonia.scm.repository.ChangesetViewer;
 import sonia.scm.repository.PermissionType;
 import sonia.scm.repository.PermissionUtil;
 import sonia.scm.repository.Repository;
@@ -393,6 +394,26 @@ public class XmlRepositoryManager extends AbstractRepositoryManager
     return repositories;
   }
 
+  /**
+   * Method description
+   *
+   *
+   * @param repository
+   *
+   * @return
+   *
+   * @throws RepositoryException
+   */
+  @Override
+  public ChangesetViewer getChangesetViewer(Repository repository)
+          throws RepositoryException
+  {
+    AssertUtil.assertIsNotNull(repository);
+    isReader(repository);
+
+    return getHandler(repository).getChangesetViewer(repository);
+  }
+
   /**
    * Method description
    *