Merge changes from topic 'inline-3'

* changes:
  InlineEdit: Add REST endpoint to retrieve commit message
  InlineEdit: Add REST endpoint to modify commit message
  InlineEdit: Add support for changing commit message

Documentation/rest-api-changes.txt

@@ -1293,6 +1293,34 @@ response "`204 No Content`" is returned.
   HTTP/1.1 204 No Content
 ----
 
+[[put-change-edit-message]]
+=== Change commit message in Change Edit
+--
+'PUT /changes/link:#change-id[\{change-id\}]/edit:message
+--
+
+Modify commit message. The request body needs to include a
+link:#change-edit-message-input[ChangeEditMessageInput]
+entity.
+
+.Request
+----
+  PUT /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/edit:message HTTP/1.0
+  Content-Type: application/json;charset=UTF-8
+
+  {
+    "message": "New commit message\n\nChange-Id: I10394472cbd17dd12454f229e4f6de00b143a444"
+  }
+----
+
+If a change edit doesn't exist for this change yet, it is created. As
+response "`204 No Content`" is returned.
+
+.Response
+----
+  HTTP/1.1 204 No Content
+----
+
 [[delete-edit-file]]
 === Delete file in Change Edit
 --
@@ -1341,6 +1369,30 @@ specified file was deleted in the change edit "`204 No Content`" is returned.
   RnJvbSA3ZGFkY2MxNTNmZGVhMTdhYTg0ZmYzMmE2ZTI0NWRiYjY...
 ----
 
+[[get-edit-message]]
+=== Retrieve commit message from Change Edit or current patch set of the change
+--
+'GET /changes/link:#change-id[\{change-id\}]/edit:message
+--
+
+Retrieves commit message from change edit or from current patch set when
+change edit doesn't exist.
+
+.Request
+----
+  GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/edit:message HTTP/1.0
+----
+
+The commit message is returned as base64 encoded string.
+
+.Response
+----
+  HTTP/1.1 200 OK
+
+  VGhpcyBpcyBhIGNvbW1pdCBtZXNzYWdlCgpDaGFuZ2UtSWQ6IElhYzhmZGM1MGRlZjFiYWUzYjAz
+M2JhNjcxZTk0OTBmNzUxNDU5ZGUzCg==
+----
+
 [[publish-edit]]
 === Publish Change Edit
 --
@@ -3912,6 +3964,17 @@ path within change edit.
 |`restore_path`|optional|Path to file to restore.
 |===========================
 
+[[change-edit-message-input]]
+=== ChangeEditMessageInput
+The `ChangeEditMessageInput` entity contains information for changing
+the commit message within a change edit.
+
+[options="header",cols="1,^1,5"]
+|===========================
+|Field Name    ||Description
+|`message`     ||New commit message.
+|===========================
+
 [[check-result]]
 === CheckResult
 The `CheckResult` entity contains the results of a consistency check on

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/edit/ChangeEditIT.java

@@ -30,12 +30,15 @@ import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.acceptance.RestSession;
+import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.common.EditInfo;
+import com.google.gerrit.extensions.common.ListChangesOption;
 import com.google.gerrit.extensions.restapi.BinaryResult;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.change.ChangeEdits.EditMessage;
 import com.google.gerrit.server.change.ChangeEdits.Post;
 import com.google.gerrit.server.change.ChangeEdits.Put;
 import com.google.gerrit.server.change.FileContentUtil;
@@ -234,6 +237,57 @@ public class ChangeEditIT extends AbstractDaemonTest {
     assertThat(edit.isPresent()).isFalse();
   }
 
+  @Test
+  public void updateMessage() throws Exception {
+    assertThat(modifier.createEdit(change, getCurrentPatchSet(changeId)))
+        .isEqualTo(RefUpdate.Result.NEW);
+    Optional<ChangeEdit> edit = editUtil.byChange(change);
+
+    try {
+      modifier.modifyMessage(
+          edit.get(),
+          edit.get().getEditCommit().getFullMessage());
+      fail("InvalidChangeOperationException expected");
+    } catch (InvalidChangeOperationException ex) {
+      assertThat(ex.getMessage()).isEqualTo(
+          "New commit message cannot be same as existing commit message");
+    }
+
+    String msg = String.format("New commit message\n\nChange-Id: %s",
+        change.getKey());
+    assertThat(modifier.modifyMessage(edit.get(), msg)).isEqualTo(
+        RefUpdate.Result.FORCED);
+    edit = editUtil.byChange(change);
+    assertThat(edit.get().getEditCommit().getFullMessage()).isEqualTo(msg);
+
+    editUtil.publish(edit.get());
+    assertThat(editUtil.byChange(change).isPresent()).isFalse();
+
+    ChangeInfo info = get(changeId, ListChangesOption.CURRENT_COMMIT,
+        ListChangesOption.CURRENT_REVISION);
+    assertThat(info.revisions.get(info.currentRevision).commit.message)
+        .isEqualTo(msg);
+  }
+
+  @Test
+  public void updateMessageRest() throws Exception {
+    EditMessage.Input in = new EditMessage.Input();
+    in.message = String.format("New commit message\n\nChange-Id: %s",
+        change.getKey());
+    assertThat(adminSession.put(urlEditMessage(), in).getStatusCode())
+        .isEqualTo(SC_NO_CONTENT);
+    Optional<ChangeEdit> edit = editUtil.byChange(change);
+    assertThat(edit.get().getEditCommit().getFullMessage())
+        .isEqualTo(in.message);
+    in.message = String.format("New commit message2\n\nChange-Id: %s",
+        change.getKey());
+    assertThat(adminSession.put(urlEditMessage(), in).getStatusCode())
+        .isEqualTo(SC_NO_CONTENT);
+    edit = editUtil.byChange(change);
+    assertThat(edit.get().getEditCommit().getFullMessage())
+        .isEqualTo(in.message);
+  }
+
   @Test
   public void retrieveEdit() throws Exception {
     RestResponse r = adminSession.get(urlEdit());
@@ -539,6 +593,12 @@ public class ChangeEditIT extends AbstractDaemonTest {
         + "/edit/";
   }
 
+  private String urlEditMessage() {
+    return "/changes/"
+        + change.getChangeId()
+        + "/edit:message";
+  }
+
   private String urlEditFile() {
     return urlEdit()
         + "/"

gerrit-server/src/main/java/com/google/gerrit/server/ChangeUtil.java

@@ -450,6 +450,36 @@ public class ChangeUtil {
     }
   }
 
+  public String getMessage(Change change)
+      throws NoSuchChangeException, OrmException,
+      MissingObjectException, IncorrectObjectTypeException, IOException {
+    Change.Id changeId = change.getId();
+    PatchSet ps = db.get().patchSets().get(change.currentPatchSetId());
+    if (ps == null) {
+      throw new NoSuchChangeException(changeId);
+    }
+
+    Repository git;
+    try {
+      git = gitManager.openRepository(change.getProject());
+    } catch (RepositoryNotFoundException e) {
+      throw new NoSuchChangeException(changeId, e);
+    }
+    try {
+      RevWalk revWalk = new RevWalk(git);
+      try {
+        RevCommit commit =
+            revWalk.parseCommit(ObjectId.fromString(ps.getRevision()
+                .get()));
+        return commit.getFullMessage();
+      } finally {
+        revWalk.release();
+      }
+    } finally {
+      git.close();
+    }
+  }
+
   public void deleteDraftChange(Change change)
       throws NoSuchChangeException, OrmException, IOException {
     Change.Id changeId = change.getId();

gerrit-server/src/main/java/com/google/gerrit/server/change/ChangeEdits.java

@@ -24,6 +24,7 @@ import com.google.gerrit.extensions.restapi.AcceptsDelete;
 import com.google.gerrit.extensions.restapi.AcceptsPost;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.BinaryResult;
 import com.google.gerrit.extensions.restapi.ChildCollection;
 import com.google.gerrit.extensions.restapi.DefaultInput;
 import com.google.gerrit.extensions.restapi.IdString;
@@ -38,12 +39,14 @@ import com.google.gerrit.extensions.restapi.RestView;
 import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.edit.ChangeEdit;
 import com.google.gerrit.server.edit.ChangeEditJson;
 import com.google.gerrit.server.edit.ChangeEditModifier;
 import com.google.gerrit.server.edit.ChangeEditUtil;
 import com.google.gerrit.server.patch.PatchListNotAvailableException;
 import com.google.gerrit.server.project.InvalidChangeOperationException;
+import com.google.gerrit.server.project.NoSuchChangeException;
 import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
@@ -434,4 +437,72 @@ public class ChangeEdits implements
       }
     }
   }
+
+  @Singleton
+  public static class EditMessage implements
+      RestModifyView<ChangeResource, EditMessage.Input> {
+    public static class Input {
+      @DefaultInput
+      public String message;
+    }
+
+    private final Provider<ReviewDb> db;
+    private final ChangeEditModifier editModifier;
+    private final ChangeEditUtil editUtil;
+
+    @Inject
+    EditMessage(Provider<ReviewDb> db,
+        ChangeEditModifier editModifier,
+        ChangeEditUtil editUtil) {
+      this.db = db;
+      this.editModifier = editModifier;
+      this.editUtil = editUtil;
+    }
+
+    @Override
+    public Object apply(ChangeResource rsrc, Input input) throws AuthException,
+        IOException, InvalidChangeOperationException, BadRequestException,
+        ResourceConflictException, OrmException {
+      Optional<ChangeEdit> edit = editUtil.byChange(rsrc.getChange());
+      if (!edit.isPresent()) {
+        editModifier.createEdit(rsrc.getChange(),
+            db.get().patchSets().get(rsrc.getChange().currentPatchSetId()));
+        edit = editUtil.byChange(rsrc.getChange());
+      }
+
+      if (input == null || Strings.isNullOrEmpty(input.message)) {
+        throw new BadRequestException("commit message must be provided");
+      }
+
+      editModifier.modifyMessage(edit.get(), input.message);
+      return Response.none();
+    }
+  }
+
+  @Singleton
+  public static class GetMessage implements RestReadView<ChangeResource> {
+    private final ChangeUtil changeUtil;
+    private final ChangeEditUtil editUtil;
+
+    @Inject
+    GetMessage(ChangeUtil changeUtil,
+        ChangeEditUtil editUtil) {
+      this.changeUtil = changeUtil;
+      this.editUtil = editUtil;
+    }
+
+    @Override
+    public BinaryResult apply(ChangeResource rsrc) throws AuthException, IOException,
+       OrmException, NoSuchChangeException {
+      Optional<ChangeEdit> edit = editUtil.byChange(rsrc.getChange());
+      // TODO(davido): Clean this up by returning 404 when edit doesn't exist.
+      // Client should call GET /changes/{id}/revisions/current/commit in this
+      // case; or, to be consistent with GET content logic, the client could
+      // call directly the right endpoint.
+      String m = edit.isPresent()
+        ? edit.get().getEditCommit().getFullMessage()
+        : changeUtil.getMessage(rsrc.getChange());
+      return BinaryResult.create(m).base64();
+    }
+  }
 }

gerrit-server/src/main/java/com/google/gerrit/server/change/Module.java

@@ -108,6 +108,8 @@ public class Module extends RestApiModule {
     delete(CHANGE_KIND, "edit").to(DeleteChangeEdit.class);
     child(CHANGE_KIND, "edit:publish").to(PublishChangeEdit.class);
     child(CHANGE_KIND, "edit:rebase").to(RebaseChangeEdit.class);
+    put(CHANGE_KIND, "edit:message").to(ChangeEdits.EditMessage.class);
+    get(CHANGE_KIND, "edit:message").to(ChangeEdits.GetMessage.class);
     put(CHANGE_EDIT_KIND, "/").to(ChangeEdits.Put.class);
     delete(CHANGE_EDIT_KIND).to(ChangeEdits.DeleteContent.class);
     get(CHANGE_EDIT_KIND, "/").to(ChangeEdits.Get.class);

gerrit-server/src/main/java/com/google/gerrit/server/edit/ChangeEditModifier.java

@@ -15,10 +15,12 @@
 package com.google.gerrit.server.edit;
 
 import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.common.base.Preconditions.checkState;
 import static com.google.gerrit.server.edit.ChangeEditUtil.editRefName;
 import static com.google.gerrit.server.edit.ChangeEditUtil.editRefPrefix;
 import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
 
+import com.google.common.base.Strings;
 import com.google.common.io.ByteStreams;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.common.TimeUtil;
@@ -216,6 +218,55 @@ public class ChangeEditModifier {
     }
   }
 
+  /**
+   * Modify commit message in existing change edit.
+   *
+   * @param edit change edit
+   * @param msg new commit message
+   * @return result
+   * @throws AuthException
+   * @throws InvalidChangeOperationException
+   * @throws IOException
+   */
+  public RefUpdate.Result modifyMessage(ChangeEdit edit, String msg)
+      throws AuthException, InvalidChangeOperationException, IOException {
+    checkState(!Strings.isNullOrEmpty(msg), "message cannot be null");
+    if (!currentUser.get().isIdentifiedUser()) {
+      throw new AuthException("Authentication required");
+    }
+    RevCommit prevEdit = edit.getEditCommit();
+    if (prevEdit.getParentCount() == 0) {
+      throw new InvalidChangeOperationException(
+          "Modify edit against root commit not supported");
+    }
+
+    if (prevEdit.getFullMessage().equals(msg)) {
+      throw new InvalidChangeOperationException(
+          "New commit message cannot be same as existing commit message");
+    }
+
+    IdentifiedUser me = (IdentifiedUser) currentUser.get();
+    Repository repo = gitManager.openRepository(edit.getChange().getProject());
+    try {
+      RevWalk rw = new RevWalk(repo);
+      ObjectInserter inserter = repo.newObjectInserter();
+      try {
+        String refName = edit.getRefName();
+        ObjectId commit = createCommit(me, inserter, prevEdit,
+            rw.parseCommit(prevEdit.getParent(0)),
+            prevEdit.getTree(),
+            msg);
+        inserter.flush();
+        return update(repo, me, refName, rw, prevEdit, commit);
+      } finally {
+        rw.release();
+        inserter.release();
+      }
+    } finally {
+      repo.close();
+    }
+  }
+
   /**
    * Modify file in existing change edit from its base commit.
    *
@@ -322,12 +373,19 @@ public class ChangeEditModifier {
 
   private ObjectId createCommit(IdentifiedUser me, ObjectInserter inserter,
       RevCommit prevEdit, RevCommit base, ObjectId tree) throws IOException {
+    return createCommit(me, inserter, prevEdit, base, tree,
+        prevEdit.getFullMessage());
+  }
+
+  private ObjectId createCommit(IdentifiedUser me, ObjectInserter inserter,
+      RevCommit prevEdit, RevCommit base, ObjectId tree, String msg)
+      throws IOException {
     CommitBuilder builder = new CommitBuilder();
     builder.setTreeId(tree);
     builder.setParentIds(base);
     builder.setAuthor(prevEdit.getAuthorIdent());
     builder.setCommitter(getCommitterIdent(me));
-    builder.setMessage(prevEdit.getFullMessage());
+    builder.setMessage(msg);
     return inserter.insert(builder);
   }
 

gerrit-server/src/main/java/com/google/gerrit/server/edit/ChangeEditUtil.java

@@ -224,8 +224,9 @@ public class ChangeEditUtil {
       throws IOException, ResourceConflictException {
     RevCommit parent = rw.parseCommit(ObjectId.fromString(
         basePatchSet.getRevision().get()));
-    if (parent.getTree().equals(edit.getTree())) {
+    if (parent.getTree().equals(edit.getTree())
-      throw new ResourceConflictException("identical tree");
+        && edit.getFullMessage().equals(parent.getFullMessage())) {
+      throw new ResourceConflictException("identical tree and message");
     }
     return writeSquashedCommit(rw, inserter, parent, edit);
   }
@@ -278,7 +279,7 @@ public class ChangeEditUtil {
       mergeCommit.addParentId(parent.getParent(i));
     }
     mergeCommit.setAuthor(parent.getAuthorIdent());
-    mergeCommit.setMessage(parent.getFullMessage());
+    mergeCommit.setMessage(edit.getFullMessage());
     mergeCommit.setCommitter(edit.getCommitterIdent());
     mergeCommit.setTreeId(edit.getTree());