// 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.googlesource.gerrit.plugins.reviewersbyblame;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Maps;
import com.google.common.collect.Ordering;
import com.google.common.collect.Sets;
import com.google.gerrit.extensions.api.GerritApi;
import com.google.gerrit.extensions.api.changes.AddReviewerInput;
import com.google.gerrit.extensions.api.changes.ReviewInput;
import com.google.gerrit.reviewdb.client.Account;
import com.google.gerrit.reviewdb.client.Change;
import com.google.gerrit.reviewdb.client.Patch.ChangeType;
import com.google.gerrit.reviewdb.client.PatchSet;
import com.google.gerrit.server.account.AccountCache;
import com.google.gerrit.server.account.AccountState;
import com.google.gerrit.server.account.Emails;
import com.google.gerrit.server.change.ChangeResource;
import com.google.gerrit.server.patch.PatchList;
import com.google.gerrit.server.patch.PatchListCache;
import com.google.gerrit.server.patch.PatchListEntry;
import com.google.gerrit.server.patch.PatchListNotAvailableException;
import com.google.gerrit.server.restapi.change.ChangesCollection;
import com.google.gerrit.server.restapi.change.PostReviewers;
import com.google.gwtorm.server.OrmException;
import com.google.inject.Inject;
import com.google.inject.Provider;
import com.google.inject.assistedinject.Assisted;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Optional;
import java.util.Set;
import org.eclipse.jgit.api.BlameCommand;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.blame.BlameResult;
import org.eclipse.jgit.diff.Edit;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevCommit;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class ReviewersByBlame implements Runnable {
private static final Logger log = LoggerFactory.getLogger(ReviewersByBlame.class);
private final RevCommit commit;
private final Change change;
private final PatchSet ps;
private final Repository repo;
private final int maxReviewers;
private final String ignoreFileRegEx;
private final List<String> ignoredUsers;
private final Emails emails;
private final AccountCache accountCache;
private final PatchListCache patchListCache;
private final
Provider<PostReviewers> reviewersProvider;
private final ChangesCollection changes;GerritApi gApi;
public interface Factory {
ReviewersByBlame create(
RevCommit commit,
Change change,
PatchSet ps,
int maxReviewers,
Repository repo,
String ignoreFileRegEx,
String[] ignoredUsers);
}
@Inject
public ReviewersByBlame(
final Emails emails,
final AccountCache accountCache,
final
ChangesCollection changes,
final Provider<PostReviewers> reviewersProviderPatchListCache patchListCache,
final PatchListCache patchListCacheGerritApi gApi,
@Assisted final RevCommit commit,
@Assisted final Change change,
@Assisted final PatchSet ps,
@Assisted final int maxReviewers,
@Assisted final Repository repo,
@Assisted final String ignoreFileRegEx,
@Assisted final String[] ignoredUsers) {
this.emails = emails;
this.accountCache = accountCache;
this.
changes = changes;
this.reviewersProvider = reviewersProvider;patchListCache = patchListCache;
this.
patchListCache = patchListCache;gApi = gApi;
this.commit = commit;
this.change = change;
this.ps = ps;
this.maxReviewers = maxReviewers;
this.repo = repo;
this.ignoreFileRegEx = ignoreFileRegEx;
this.ignoredUsers = ignoredUsers == null ? ImmutableList.of() : Arrays.asList(ignoredUsers);
}
@Override
public void run() {
Map<Account, Integer> reviewers = Maps.newHashMap();
PatchList patchList;
try {
patchList = patchListCache.get(change, ps);
} catch (PatchListNotAvailableException ex) {
log.error("Couldn't load patchlist for change {}", change.getKey(), ex);
return;
}
// Ignore merges and initial commit.
if (commit.getParentCount() != 1) {
return;
}
for (PatchListEntry entry : patchList.getPatches()) {
BlameResult blameResult;
if ((entry.getChangeType() == ChangeType.MODIFIED
|| entry.getChangeType() == ChangeType.DELETED)
&& (ignoreFileRegEx.isEmpty() || !entry.getNewName().matches(ignoreFileRegEx))
&& (blameResult = computeBlame(entry, commit.getParent(0))) != null) {
List<Edit> edits = entry.getEdits();
reviewers.putAll(getReviewersForPatch(edits, blameResult));
}
}
Set<Account.Id> topReviewers = findTopReviewers(reviewers);
addReviewers(topReviewers, change);
}
/**
* Append the reviewers to change#{@link Change}
*
* @param topReviewers Set of reviewers proposed
* @param change {@link Change} to add the reviewers to
*/
private void addReviewers(Set<Account.Id> topReviewers, Change change) {
try {
ChangeResource changeResource = changes.parse(change.getId());ReviewInput in = new ReviewInput();
PostRin.reviewers
post = reviewersProvider.get();= new ArrayList<>(topReviewers.size());
for (Account.Id account
Id : topReviewers) {
AddReviewerInput
iaddReviewerInput = new AddReviewerInput();
iaddReviewerInput.reviewer = account
Id.toString();
post.apply(changeResource, iin.reviewers.add(addReviewerInput);
}
gApi.changes().id(change.getChangeId()).current().review(in);
} catch (Exception ex) {
log.error("Couldn't add reviewers to the change", ex);
}
}
/**
* Create a set of reviewers based on data collected from line annotations, the reviewers are
* ordered by their weight and n greatest of the entries are chosen, where n is the maximum number
* of reviewers
*
* @param reviewers A set of reviewers with their weight mapped to their {@link Account}
* @return Reviewers that are best matches for this change, empty if none, never <code>null</code>
*/
private Set<Account.Id> findTopReviewers(final Map<Account, Integer> reviewers) {
Set<Account.Id> topReviewers = Sets.newHashSet();
List<Entry<Account, Integer>> entries =
Ordering.from(
new Comparator<Entry<Account, Integer>>() {
@Override
public int compare(
Entry<Account, Integer> first, Entry<Account, Integer> second) {
return first.getValue() - second.getValue();
}
})
.greatestOf(reviewers.entrySet(), this.maxReviewers);
for (Entry<Account, Integer> entry : entries) {
topReviewers.add(entry.getKey().getId());
}
return topReviewers;
}
/**
* Get a map of all the possible reviewers based on the provided blame data
*
* @param edits List of edits that were made for this patch
* @param blameResult Result of blame computation
* @return a set of all possible reviewers, empty if none, never <code>null</code>
*/
private Map<Account, Integer> getReviewersForPatch(
final List<Edit> edits, final BlameResult blameResult) {
Map<Account, Integer> reviewers = Maps.newHashMap();
for (Edit edit : edits) {
for (int i = edit.getBeginA(); i < edit.getEndA(); i++) {
RevCommit commit = blameResult.getSourceCommit(i);
try {
Set<Account.Id> ids = emails.getAccountFor(commit.getAuthorIdent().getEmailAddress());
for (Account.Id id : ids) {
Optional<AccountState> state = accountCache.get(id);
Optional<Account> getAccountState = state.map(AccountState::getAccount);
Optional<String> username = state.get().getUserName();
if (getAccountState.isPresent()) {
Account account = getAccountState.get();
if (account.isActive()
&& !change.getOwner().equals(account.getId())
&& (username == null || !ignoredUsers.contains(username.get()))) {
Integer count = reviewers.get(account);
reviewers.put(account, count == null ? 1 : count.intValue() + 1);
}
}
}
} catch (IOException | OrmException e) {
throw new RuntimeException(
"Unable to get account with email: " + commit.getAuthorIdent().getEmailAddress(), e);
}
}
}
return reviewers;
}
/**
* Compute the blame data for the parent, we are not interested in the specific commit but the
* parent, since we only want to know the last person that edited this specific part of the code.
*
* @param entry {@link PatchListEntry}
* @param parent Parent {@link RevCommit}
* @return Result of blame computation, null if the computation fails
*/
private BlameResult computeBlame(final PatchListEntry entry, final RevCommit parent) {
BlameCommand blameCommand = new BlameCommand(repo);
blameCommand.setStartCommit(parent);
blameCommand.setFilePath(entry.getNewName());
try {
BlameResult blameResult = blameCommand.call();
blameResult.computeAll();
return blameResult;
} catch (GitAPIException ex) {
log.error("Couldn't execute blame for commit {}", parent.getName(), ex);
} catch (IOException err) {
log.error("Error while computing blame for commit {}", parent.getName(), err);
}
return null;
}
}