| // Copyright (C) 2017 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.gerrit.common.Nullable; |
| import com.google.gerrit.extensions.common.PureRevertInfo; |
| import com.google.gerrit.extensions.restapi.BadRequestException; |
| import com.google.gerrit.extensions.restapi.ResourceConflictException; |
| import com.google.gerrit.reviewdb.client.PatchSet; |
| import com.google.gerrit.reviewdb.server.ReviewDb; |
| import com.google.gerrit.server.PatchSetUtil; |
| import com.google.gerrit.server.git.GitRepositoryManager; |
| import com.google.gerrit.server.git.MergeUtil; |
| import com.google.gerrit.server.notedb.ChangeNotes; |
| import com.google.gerrit.server.project.ProjectCache; |
| import com.google.gwtorm.server.OrmException; |
| import com.google.inject.Inject; |
| import com.google.inject.Provider; |
| import com.google.inject.Singleton; |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.util.List; |
| import org.eclipse.jgit.diff.DiffEntry; |
| import org.eclipse.jgit.diff.DiffFormatter; |
| import org.eclipse.jgit.errors.InvalidObjectIdException; |
| import org.eclipse.jgit.errors.MissingObjectException; |
| import org.eclipse.jgit.lib.ObjectId; |
| import org.eclipse.jgit.lib.ObjectInserter; |
| import org.eclipse.jgit.lib.Repository; |
| import org.eclipse.jgit.merge.ThreeWayMerger; |
| import org.eclipse.jgit.revwalk.RevCommit; |
| import org.eclipse.jgit.revwalk.RevWalk; |
| |
| @Singleton |
| public class PureRevert { |
| private final MergeUtil.Factory mergeUtilFactory; |
| private final GitRepositoryManager repoManager; |
| private final ProjectCache projectCache; |
| private final ChangeNotes.Factory notesFactory; |
| private final Provider<ReviewDb> dbProvider; |
| private final PatchSetUtil psUtil; |
| |
| @Inject |
| PureRevert( |
| MergeUtil.Factory mergeUtilFactory, |
| GitRepositoryManager repoManager, |
| ProjectCache projectCache, |
| ChangeNotes.Factory notesFactory, |
| Provider<ReviewDb> dbProvider, |
| PatchSetUtil psUtil) { |
| this.mergeUtilFactory = mergeUtilFactory; |
| this.repoManager = repoManager; |
| this.projectCache = projectCache; |
| this.notesFactory = notesFactory; |
| this.dbProvider = dbProvider; |
| this.psUtil = psUtil; |
| } |
| |
| public PureRevertInfo get(ChangeNotes notes, @Nullable String claimedOriginal) |
| throws OrmException, IOException, BadRequestException, ResourceConflictException { |
| PatchSet currentPatchSet = psUtil.current(dbProvider.get(), notes); |
| if (currentPatchSet == null) { |
| throw new ResourceConflictException("current revision is missing"); |
| } |
| |
| if (claimedOriginal == null) { |
| if (notes.getChange().getRevertOf() == null) { |
| throw new BadRequestException("no ID was provided and change isn't a revert"); |
| } |
| PatchSet ps = |
| psUtil.current( |
| dbProvider.get(), |
| notesFactory.createChecked( |
| dbProvider.get(), notes.getProjectName(), notes.getChange().getRevertOf())); |
| claimedOriginal = ps.getRevision().get(); |
| } |
| |
| try (Repository repo = repoManager.openRepository(notes.getProjectName()); |
| ObjectInserter oi = repo.newObjectInserter(); |
| RevWalk rw = new RevWalk(repo)) { |
| RevCommit claimedOriginalCommit; |
| try { |
| claimedOriginalCommit = rw.parseCommit(ObjectId.fromString(claimedOriginal)); |
| } catch (InvalidObjectIdException | MissingObjectException e) { |
| throw new BadRequestException("invalid object ID"); |
| } |
| if (claimedOriginalCommit.getParentCount() == 0) { |
| throw new BadRequestException("can't check against initial commit"); |
| } |
| RevCommit claimedRevertCommit = |
| rw.parseCommit(ObjectId.fromString(currentPatchSet.getRevision().get())); |
| if (claimedRevertCommit.getParentCount() == 0) { |
| throw new BadRequestException("claimed revert has no parents"); |
| } |
| // Rebase claimed revert onto claimed original |
| ThreeWayMerger merger = |
| mergeUtilFactory |
| .create(projectCache.checkedGet(notes.getProjectName())) |
| .newThreeWayMerger(oi, repo.getConfig()); |
| merger.setBase(claimedRevertCommit.getParent(0)); |
| boolean success = merger.merge(claimedRevertCommit, claimedOriginalCommit); |
| if (!success || merger.getResultTreeId() == null) { |
| // Merge conflict during rebase |
| return new PureRevertInfo(false); |
| } |
| |
| // Any differences between claimed original's parent and the rebase result indicate that the |
| // claimedRevert is not a pure revert but made content changes |
| try (DiffFormatter df = new DiffFormatter(new ByteArrayOutputStream())) { |
| df.setReader(oi.newReader(), repo.getConfig()); |
| List<DiffEntry> entries = |
| df.scan(claimedOriginalCommit.getParent(0), merger.getResultTreeId()); |
| return new PureRevertInfo(entries.isEmpty()); |
| } |
| } |
| } |
| } |