| // Copyright (C) 2020 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.plugins.codeowners.backend; |
| |
| import static com.google.common.base.Preconditions.checkState; |
| import static com.google.common.collect.ImmutableSet.toImmutableSet; |
| import static java.util.Objects.requireNonNull; |
| |
| import com.google.common.collect.ImmutableSet; |
| import com.google.common.flogger.FluentLogger; |
| import com.google.gerrit.entities.Patch; |
| import com.google.gerrit.entities.Project; |
| import com.google.gerrit.extensions.client.DiffPreferencesInfo.Whitespace; |
| import com.google.gerrit.plugins.codeowners.api.MergeCommitStrategy; |
| import com.google.gerrit.plugins.codeowners.config.CodeOwnersPluginConfiguration; |
| import com.google.gerrit.server.change.RevisionResource; |
| import com.google.gerrit.server.git.GitRepositoryManager; |
| import com.google.gerrit.server.patch.PatchListCache; |
| import com.google.gerrit.server.patch.PatchListKey; |
| import com.google.gerrit.server.patch.PatchListNotAvailableException; |
| import com.google.inject.Inject; |
| import com.google.inject.Singleton; |
| import java.io.IOException; |
| import java.util.List; |
| import org.eclipse.jgit.diff.DiffEntry; |
| import org.eclipse.jgit.diff.DiffFormatter; |
| import org.eclipse.jgit.diff.RawTextComparator; |
| import org.eclipse.jgit.lib.Config; |
| import org.eclipse.jgit.lib.ObjectId; |
| import org.eclipse.jgit.lib.Repository; |
| import org.eclipse.jgit.revwalk.RevCommit; |
| import org.eclipse.jgit.revwalk.RevWalk; |
| import org.eclipse.jgit.util.io.DisabledOutputStream; |
| |
| /** |
| * Class to compute the files that have been changed in a revision. |
| * |
| * <p>The file diff is newly computed on each access and not retrieved from any cache. This is |
| * better than using {@link com.google.gerrit.server.patch.PatchListCache} which does a lot of |
| * unneeded computations and hence is slower. The Gerrit diff caches are currently being redesigned. |
| * Once the envisioned {@code ModifiedFilesCache} is available we should consider using it. |
| */ |
| @Singleton |
| public class ChangedFiles { |
| private static final FluentLogger logger = FluentLogger.forEnclosingClass(); |
| |
| private final GitRepositoryManager repoManager; |
| private final CodeOwnersPluginConfiguration codeOwnersPluginConfiguration; |
| private final PatchListCache patchListCache; |
| |
| @Inject |
| public ChangedFiles( |
| GitRepositoryManager repoManager, |
| CodeOwnersPluginConfiguration codeOwnersPluginConfiguration, |
| PatchListCache patchListCache) { |
| this.repoManager = repoManager; |
| this.codeOwnersPluginConfiguration = codeOwnersPluginConfiguration; |
| this.patchListCache = patchListCache; |
| } |
| |
| /** |
| * Computes the files that have been changed in the given revision. |
| * |
| * <p>The diff is computed against the parent commit. |
| * |
| * @param revisionResource the revision resource for which the changed files should be computed |
| * @return the files that have been changed in the given revision |
| * @throws IOException thrown if the computation fails due to an I/O error |
| * @throws PatchListNotAvailableException thrown if getting the patch list for a merge commit |
| * against the auto merge failed |
| */ |
| public ImmutableSet<ChangedFile> compute(RevisionResource revisionResource) |
| throws IOException, PatchListNotAvailableException { |
| requireNonNull(revisionResource, "revisionResource"); |
| return compute(revisionResource.getProject(), revisionResource.getPatchSet().commitId()); |
| } |
| |
| /** |
| * Computes the files that have been changed in the given revision. |
| * |
| * <p>The diff is computed against the parent commit. |
| * |
| * @param project the project |
| * @param revision the revision for which the changed files should be computed |
| * @return the files that have been changed in the given revision |
| * @throws IOException thrown if the computation fails due to an I/O error |
| * @throws PatchListNotAvailableException thrown if getting the patch list for a merge commit |
| * against the auto merge failed |
| */ |
| public ImmutableSet<ChangedFile> compute(Project.NameKey project, ObjectId revision) |
| throws IOException, PatchListNotAvailableException { |
| requireNonNull(project, "project"); |
| requireNonNull(revision, "revision"); |
| |
| try (Repository repository = repoManager.openRepository(project); |
| RevWalk revWalk = new RevWalk(repository)) { |
| RevCommit revCommit = revWalk.parseCommit(revision); |
| return compute(project, repository.getConfig(), revWalk, revCommit); |
| } |
| } |
| |
| public ImmutableSet<ChangedFile> compute( |
| Project.NameKey project, Config repoConfig, RevWalk revWalk, RevCommit revCommit) |
| throws IOException, PatchListNotAvailableException { |
| requireNonNull(project, "project"); |
| requireNonNull(repoConfig, "repoConfig"); |
| requireNonNull(revWalk, "revWalk"); |
| requireNonNull(revCommit, "revCommit"); |
| |
| logger.atFine().log( |
| "computing changed files for revision %s in project %s", revCommit.name(), project); |
| |
| if (revCommit.getParentCount() > 1 |
| && MergeCommitStrategy.FILES_WITH_CONFLICT_RESOLUTION.equals( |
| codeOwnersPluginConfiguration.getMergeCommitStrategy(project))) { |
| return computeByComparingAgainstAutoMerge(project, revCommit); |
| } |
| |
| return computeByComparingAgainstFirstParent(repoConfig, revWalk, revCommit); |
| } |
| |
| /** |
| * Computes the changed files by comparing the given merge commit against the auto merge. |
| * |
| * <p>Since computing the auto merge is expensive, we do not compute it and diff against it on our |
| * own, but rather ask the patch list cache for it. |
| * |
| * @param project the project that contains the merge commit |
| * @param mergeCommit the merge commit for which the changed files should be computed |
| * @return the changed files for the given merge commit |
| */ |
| private ImmutableSet<ChangedFile> computeByComparingAgainstAutoMerge( |
| Project.NameKey project, RevCommit mergeCommit) throws PatchListNotAvailableException { |
| checkState( |
| mergeCommit.getParentCount() > 1, "expected %s to be a merge commit", mergeCommit.name()); |
| |
| // for merge commits the default base is the auto merge commit |
| PatchListKey patchListKey = |
| PatchListKey.againstDefaultBase(mergeCommit, Whitespace.IGNORE_NONE); |
| |
| return patchListCache.get(patchListKey, project).getPatches().stream() |
| .filter( |
| patchListEntry -> |
| patchListEntry.getNewName() == null || !Patch.isMagic(patchListEntry.getNewName())) |
| .map(ChangedFile::create) |
| .collect(toImmutableSet()); |
| } |
| |
| /** |
| * Computes the changed files by comparing the given commit against its first parent. |
| * |
| * <p>The computation also works if the commit doesn't have any parent. |
| * |
| * @param repoConfig the repository configuration |
| * @param revWalk the rev walk |
| * @param revCommit the commit for which the changed files should be computed |
| * @return the changed files for the given commit |
| */ |
| private ImmutableSet<ChangedFile> computeByComparingAgainstFirstParent( |
| Config repoConfig, RevWalk revWalk, RevCommit revCommit) throws IOException { |
| RevCommit baseCommit = revCommit.getParentCount() > 0 ? revCommit.getParent(0) : null; |
| logger.atFine().log("baseCommit = %s", baseCommit != null ? baseCommit.name() : "n/a"); |
| |
| try (DiffFormatter diffFormatter = new DiffFormatter(DisabledOutputStream.INSTANCE)) { |
| diffFormatter.setReader(revWalk.getObjectReader(), repoConfig); |
| diffFormatter.setDiffComparator(RawTextComparator.DEFAULT); |
| diffFormatter.setDetectRenames(true); |
| List<DiffEntry> diffEntries = diffFormatter.scan(baseCommit, revCommit); |
| ImmutableSet<ChangedFile> changedFiles = |
| diffEntries.stream().map(ChangedFile::create).collect(toImmutableSet()); |
| logger.atFine().log("changed files = %s", changedFiles); |
| return changedFiles; |
| } |
| } |
| } |