// Copyright (C) 2013 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.gerrit.server.change;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import com.google.gerrit.common.TimeUtil;
import com.google.gerrit.common.errors.EmailException;
import com.google.gerrit.extensions.api.changes.RebaseInput;
import com.google.gerrit.extensions.client.ListChangesOption;
import com.google.gerrit.extensions.common.ChangeInfo;
import com.google.gerrit.extensions.restapi.AuthException;
import com.google.gerrit.extensions.restapi.ResourceConflictException;
import com.google.gerrit.extensions.restapi.RestApiException;
import com.google.gerrit.extensions.restapi.RestModifyView;
import com.google.gerrit.extensions.webui.UiAction;
import com.google.gerrit.reviewdb.client.Branch;
import com.google.gerrit.reviewdb.client.Change;
import com.google.gerrit.reviewdb.client.Change.Status;
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.PatchSetUtil;
import com.google.gerrit.server.change.RebaseUtil.Base;
import com.google.gerrit.server.git.GitRepositoryManager;
import com.google.gerrit.server.permissions.ChangePermission;
import com.google.gerrit.server.permissions.PermissionBackendException;
import com.google.gerrit.server.project.ChangeControl;
import com.google.gerrit.server.project.NoSuchChangeException;
import com.google.gerrit.server.update.BatchUpdate;
import com.google.gerrit.server.update.RetryHelper;
import com.google.gerrit.server.update.RetryingRestModifyView;
import com.google.gerrit.server.update.UpdateException;
import com.google.gwtorm.server.OrmException;
import com.google.inject.Inject;
import com.google.inject.Provider;
import com.google.inject.Singleton;
import java.io.IOException;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectInserter;
import org.eclipse.jgit.lib.ObjectReader;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevWalk;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@Singleton
public class Rebase extends RetryingRestModifyView<RevisionResource, RebaseInput, ChangeInfo>
implements RestModifyView<RevisionResource, RebaseInput>, UiAction<RevisionResource> {
private static final Logger log = LoggerFactory.getLogger(Rebase.class);
private static final ImmutableSet<ListChangesOption> OPTIONS =
Sets.immutableEnumSet(ListChangesOption.CURRENT_REVISION, ListChangesOption.CURRENT_COMMIT);
private final GitRepositoryManager repoManager;
private final RebaseChangeOp.Factory rebaseFactory;
private final RebaseUtil rebaseUtil;
private final ChangeJson.Factory json;
private final Provider<ReviewDb> dbProvider;
@Inject
public Rebase(
RetryHelper retryHelper,
GitRepositoryManager repoManager,
RebaseChangeOp.Factory rebaseFactory,
RebaseUtil rebaseUtil,
ChangeJson.Factory json,
Provider<ReviewDb> dbProvider) {
super(retryHelper);
this.repoManager = repoManager;
this.rebaseFactory = rebaseFactory;
this.rebaseUtil = rebaseUtil;
this.json = json;
this.dbProvider = dbProvider;
}
@Override
protected ChangeInfo applyImpl(
BatchUpdate.Factory updateFactory, RevisionResource rsrc, RebaseInput input)
throws EmailException, OrmException, UpdateException, RestApiException, IOException,
NoSuchChangeException, PermissionBackendException {
rsrc.permissions().database(dbProvider).check(ChangePermission.REBASE);
ChangeControl control = rsrc.getControl();
Change change = rsrc.getChange();
try (Repository repo = repoManager.openRepository(change.getProject());
ObjectInserter oi = repo.newObjectInserter();
ObjectReader reader = oi.newReader();
RevWalk rw = new RevWalk(reader);
BatchUpdate bu =
updateFactory.create(
dbProvider.get(), change.getProject(), rsrc.getUser(), TimeUtil.nowTs())) {
if (!change.getStatus().isOpen()) {
throw new ResourceConflictException("change is " + ChangeUtil.status(change));
} else if (!hasOneParent(rw, rsrc.getPatchSet())) {
throw new ResourceConflictException(
"cannot rebase merge commits or commit with no ancestor");
}
bu.setRepository(repo, rw, oi);
bu.addOp(
change.getId(),
rebaseFactory
.create(control, rsrc.getPatchSet(), findBaseRev(repo, rw, rsrc, input))
.setForceContentMerge(true)
.setFireRevisionCreated(true));
bu.execute();
}
return json.create(OPTIONS).format(change.getProject(), change.getId());
}
private ObjectId findBaseRev(
Repository repo, RevWalk rw, RevisionResource rsrc, RebaseInput input)
throws RestApiException, OrmException, IOException, NoSuchChangeException {
Branch.NameKey destRefKey = rsrc.getChange().getDest();
if (input == null || input.base == null) {
return rebaseUtil.findBaseRevision(rsrc.getPatchSet(), destRefKey, repo, rw);
}
Change change = rsrc.getChange();
String str = input.base.trim();
if (str.equals("")) {
// Remove existing dependency to other patch set.
Ref destRef = repo.exactRef(destRefKey.get());
if (destRef == null) {
throw new ResourceConflictException(
"can't rebase onto tip of branch " + destRefKey.get() + "; branch doesn't exist");
}
return destRef.getObjectId();
}
@SuppressWarnings("resource")
ReviewDb db = dbProvider.get();
Base base = rebaseUtil.parseBase(rsrc, str);
if (base == null) {
throw new ResourceConflictException("base revision is missing: " + str);
}
PatchSet.Id baseId = base.patchSet().getId();
if (!base.control().isPatchVisible(base.patchSet(), db)) {
throw new AuthException("base revision not accessible: " + str);
} else if (change.getId().equals(baseId.getParentKey())) {
throw new ResourceConflictException("cannot rebase change onto itself");
}
Change baseChange = base.control().getChange();
if (!baseChange.getProject().equals(change.getProject())) {
throw new ResourceConflictException(
"base change is in wrong project: " + baseChange.getProject());
} else if (!baseChange.getDest().equals(change.getDest())) {
throw new ResourceConflictException(
"base change is targeting wrong branch: " + baseChange.getDest());
} else if (baseChange.getStatus() == Status.ABANDONED) {
throw new ResourceConflictException("base change is abandoned: " + baseChange.getKey());
} else if (isMergedInto(rw, rsrc.getPatchSet(), base.patchSet())) {
throw new ResourceConflictException(
"base change "
+ baseChange.getKey()
+ " is a descendant of the current change - recursion not allowed");
}
return ObjectId.fromString(base.patchSet().getRevision().get());
}
private boolean isMergedInto(RevWalk rw, PatchSet base, PatchSet tip) throws IOException {
ObjectId baseId = ObjectId.fromString(base.getRevision().get());
ObjectId tipId = ObjectId.fromString(tip.getRevision().get());
return rw.isMergedInto(rw.parseCommit(baseId), rw.parseCommit(tipId));
}
private boolean hasOneParent(RevWalk rw, PatchSet ps) throws IOException {
// Prevent rebase of exotic changes (merge commit, no ancestor).
RevCommit c = rw.parseCommit(ObjectId.fromString(ps.getRevision().get()));
return c.getParentCount() == 1;
}
@Override
public UiAction.Description getDescription(RevisionResource resource) {
PatchSet patchSet = resource.getPatchSet();
Change change = resource.getChange();
Branch.NameKey dest = change.getDest();
boolean visible =
change.getStatus().isOpen()
&& resource.isCurrent()
&& resource.permissions().database(dbProvider).testOrFalse(ChangePermission.REBASE);
boolean enabled = true;
if (visible) {
try (Repository repo = repoManager.openRepository(dest.getParentKey());
RevWalk rw = new RevWalk(repo)) {
visible = hasOneParent(rw, resource.getPatchSet());
enabled = rebaseUtil.canRebase(patchSet, dest, repo, rw);
} catch (IOException e) {
log.error("Failed to check if patch set can be rebased: " + resource.getPatchSet(), e);
visible = false;
}
}
return new UiAction.Description()
.setLabel("Rebase")
.setTitle("Rebase onto tip of branch or parent change")
.setVisible(visible)
.setEnabled(enabled);
}
public static class CurrentRevision
extends RetryingRestModifyView<ChangeResource, RebaseInput, ChangeInfo> {
private final PatchSetUtil psUtil;
private final Rebase rebase;
@Inject
CurrentRevision(RetryHelper retryHelper, PatchSetUtil psUtil, Rebase rebase) {
super(retryHelper);
this.psUtil = psUtil;
this.rebase = rebase;
}
@Override
protected ChangeInfo applyImpl(
BatchUpdate.Factory updateFactory, ChangeResource rsrc, RebaseInput input)
throws EmailException, OrmException, UpdateException, RestApiException, IOException,
PermissionBackendException {
PatchSet ps = psUtil.current(rebase.dbProvider.get(), rsrc.getNotes());
if (ps == null) {
throw new ResourceConflictException("current revision is missing");
} else if (!rsrc.getControl().isPatchVisible(ps, rebase.dbProvider.get())) {
throw new AuthException("current revision not accessible");
}
return rebase.applyImpl(updateFactory, new RevisionResource(rsrc, ps), input);
}
}
}