// 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.project;
import static org.eclipse.jgit.lib.RefDatabase.ALL;
import com.google.gerrit.common.ChangeHooks;
import com.google.gerrit.common.errors.InvalidRevisionException;
import com.google.gerrit.extensions.restapi.AuthException;
import com.google.gerrit.extensions.restapi.BadRequestException;
import com.google.gerrit.extensions.restapi.DefaultInput;
import com.google.gerrit.extensions.restapi.ResourceConflictException;
import com.google.gerrit.extensions.restapi.RestModifyView;
import com.google.gerrit.reviewdb.client.Branch;
import com.google.gerrit.reviewdb.client.Project;
import com.google.gerrit.server.IdentifiedUser;
import com.google.gerrit.server.extensions.events.GitReferenceUpdated;
import com.google.gerrit.server.git.GitRepositoryManager;
import com.google.gerrit.server.project.CreateBranch.Input;
import com.google.gerrit.server.project.ListBranches.BranchInfo;
import com.google.gerrit.server.util.MagicBranch;
import com.google.inject.Inject;
import com.google.inject.Provider;
import com.google.inject.assistedinject.Assisted;
import org.eclipse.jgit.errors.IncorrectObjectTypeException;
import org.eclipse.jgit.errors.MissingObjectException;
import org.eclipse.jgit.errors.RevisionSyntaxException;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.RefUpdate;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.ObjectWalk;
import org.eclipse.jgit.revwalk.RevObject;
import org.eclipse.jgit.revwalk.RevWalk;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
public class CreateBranch implements RestModifyView<ProjectResource, Input> {
private static final Logger log = LoggerFactory.getLogger(CreateBranch.class);
public static class Input {
public String ref;
@DefaultInput
public String revision;
}
public static interface Factory {
CreateBranch create(String ref);
}
private final Provider<IdentifiedUser> identifiedUser;
private final GitRepositoryManager repoManager;
private final GitReferenceUpdated referenceUpdated;
private final ChangeHooks hooks;
private String ref;
@Inject
CreateBranch(Provider<IdentifiedUser> identifiedUser,
GitRepositoryManager repoManager,
GitReferenceUpdated referenceUpdated, ChangeHooks hooks,
@Assisted String ref) {
this.identifiedUser = identifiedUser;
this.repoManager = repoManager;
this.referenceUpdated = referenceUpdated;
this.hooks = hooks;
this.ref = ref;
}
@Override
public BranchInfo apply(ProjectResource rsrc, Input input)
throws BadRequestException, AuthException, ResourceConflictException,
IOException {
if (input == null) {
input = new Input();
}
if (input.ref != null && !ref.equals(input.ref)) {
throw new BadRequestException("ref must match URL");
}
if (input.revision == null) {
input.revision = Constants.HEAD;
}
while (ref.startsWith("/")) {
ref = ref.substring(1);
}
if (!ref.startsWith(Constants.R_REFS)) {
ref = Constants.R_HEADS + ref;
}
if (!Repository.isValidRefName(ref)) {
throw new BadRequestException("invalid branch name \"" + ref + "\"");
}
if (MagicBranch.isMagicBranch(ref)) {
throw new BadRequestException("not allowed to create branches under \""
+ MagicBranch.getMagicRefNamePrefix(ref) + "\"");
}
final Branch.NameKey name = new Branch.NameKey(rsrc.getNameKey(), ref);
final RefControl refControl = rsrc.getControl().controlForRef(name);
final Repository repo = repoManager.openRepository(rsrc.getNameKey());
try {
final ObjectId revid = parseBaseRevision(repo, rsrc.getNameKey(), input.revision);
final RevWalk rw = verifyConnected(repo, revid);
RevObject object = rw.parseAny(revid);
if (ref.startsWith(Constants.R_HEADS)) {
// Ensure that what we start the branch from is a commit. If we
// were given a tag, deference to the commit instead.
//
try {
object = rw.parseCommit(object);
} catch (IncorrectObjectTypeException notCommit) {
throw new BadRequestException("\"" + input.revision + "\" not a commit");
}
}
if (!refControl.canCreate(rw, object, true)) {
throw new AuthException("Cannot create \"" + ref + "\"");
}
try {
final RefUpdate u = repo.updateRef(ref);
u.setExpectedOldObjectId(ObjectId.zeroId());
u.setNewObjectId(object.copy());
u.setRefLogIdent(identifiedUser.get().newRefLogIdent());
u.setRefLogMessage("created via REST from " + input.revision, false);
final RefUpdate.Result result = u.update(rw);
switch (result) {
case FAST_FORWARD:
case NEW:
case NO_CHANGE:
referenceUpdated.fire(name.getParentKey(), u);
hooks.doRefUpdatedHook(name, u, identifiedUser.get().getAccount());
break;
case LOCK_FAILURE:
if (repo.getRef(ref) != null) {
throw new ResourceConflictException("branch \"" + ref
+ "\" already exists");
}
String refPrefix = getRefPrefix(ref);
while (!Constants.R_HEADS.equals(refPrefix)) {
if (repo.getRef(refPrefix) != null) {
throw new ResourceConflictException("Cannot create branch \""
+ ref + "\" since it conflicts with branch \"" + refPrefix
+ "\".");
}
refPrefix = getRefPrefix(refPrefix);
}
default: {
throw new IOException(result.name());
}
}
return new BranchInfo(ref, revid.getName(), refControl.canDelete());
} catch (IOException err) {
log.error("Cannot create branch \"" + name + "\"", err);
throw err;
}
} catch (InvalidRevisionException e) {
throw new BadRequestException("invalid revision \"" + input.revision + "\"");
} finally {
repo.close();
}
}
private static String getRefPrefix(final String refName) {
final int i = refName.lastIndexOf('/');
if (i > Constants.R_HEADS.length() - 1) {
return refName.substring(0, i);
}
return Constants.R_HEADS;
}
private ObjectId parseBaseRevision(Repository repo,
Project.NameKey projectName, String baseRevision)
throws InvalidRevisionException {
try {
final ObjectId revid = repo.resolve(baseRevision);
if (revid == null) {
throw new InvalidRevisionException();
}
return revid;
} catch (IOException err) {
log.error("Cannot resolve \"" + baseRevision + "\" in project \""
+ projectName.get() + "\"", err);
throw new InvalidRevisionException();
} catch (RevisionSyntaxException err) {
log.error("Invalid revision syntax \"" + baseRevision + "\"", err);
throw new InvalidRevisionException();
}
}
private RevWalk verifyConnected(final Repository repo, final ObjectId revid)
throws InvalidRevisionException {
try {
final ObjectWalk rw = new ObjectWalk(repo);
try {
rw.markStart(rw.parseCommit(revid));
} catch (IncorrectObjectTypeException err) {
throw new InvalidRevisionException();
}
for (final Ref r : repo.getRefDatabase().getRefs(ALL).values()) {
try {
rw.markUninteresting(rw.parseAny(r.getObjectId()));
} catch (MissingObjectException err) {
continue;
}
}
rw.checkConnectivity();
return rw;
} catch (IncorrectObjectTypeException err) {
throw new InvalidRevisionException();
} catch (MissingObjectException err) {
throw new InvalidRevisionException();
} catch (IOException err) {
log.error("Repository \"" + repo.getDirectory()
+ "\" may be corrupt; suggest running git fsck", err);
throw new InvalidRevisionException();
}
}
}