diff options
Diffstat (limited to 'gerrit-server/src/main/java/com/google/gerrit/server/update/RepoView.java')
| -rw-r--r-- | gerrit-server/src/main/java/com/google/gerrit/server/update/RepoView.java | 234 |
1 files changed, 0 insertions, 234 deletions
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/update/RepoView.java b/gerrit-server/src/main/java/com/google/gerrit/server/update/RepoView.java deleted file mode 100644 index 8839dbebc7..0000000000 --- a/gerrit-server/src/main/java/com/google/gerrit/server/update/RepoView.java +++ /dev/null @@ -1,234 +0,0 @@ -// 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.update; - -import static com.google.common.base.Preconditions.checkArgument; -import static com.google.common.base.Preconditions.checkNotNull; - -import com.google.common.collect.Maps; -import com.google.gerrit.reviewdb.client.Project; -import com.google.gerrit.server.git.GitRepositoryManager; -import java.io.IOException; -import java.util.HashMap; -import java.util.Map; -import java.util.Optional; -import org.eclipse.jgit.lib.Config; -import org.eclipse.jgit.lib.ObjectId; -import org.eclipse.jgit.lib.ObjectInserter; -import org.eclipse.jgit.lib.Ref; -import org.eclipse.jgit.lib.Repository; -import org.eclipse.jgit.revwalk.RevWalk; - -/** - * Restricted view of a {@link Repository} for use by {@link BatchUpdateOp} implementations. - * - * <p>This class serves two purposes in the context of {@link BatchUpdate}. First, the subset of - * normal Repository functionality is purely read-only, which prevents implementors from modifying - * the repository outside of {@link BatchUpdateOp#updateRepo}. Write operations can only be - * performed by calling methods on {@link RepoContext}. - * - * <p>Second, the read methods take into account any pending operations on the repository that - * implementations have staged using the write methods on {@link RepoContext}. Callers do not have - * to worry about whether operations have been performed yet, and the implementation details may - * differ between ReviewDb and NoteDb, but callers just don't need to care. - */ -public class RepoView { - private final Repository repo; - private final RevWalk rw; - private final ObjectInserter inserter; - private final ObjectInserter inserterWrapper; - private final ChainedReceiveCommands commands; - private final boolean closeRepo; - - RepoView(GitRepositoryManager repoManager, Project.NameKey project) throws IOException { - repo = repoManager.openRepository(project); - inserter = repo.newObjectInserter(); - inserterWrapper = new NonFlushingInserter(inserter); - rw = new RevWalk(inserter.newReader()); - commands = new ChainedReceiveCommands(repo); - closeRepo = true; - } - - RepoView(Repository repo, RevWalk rw, ObjectInserter inserter) { - checkArgument( - rw.getObjectReader().getCreatedFromInserter() == inserter, - "expected RevWalk %s to be created by ObjectInserter %s", - rw, - inserter); - this.repo = checkNotNull(repo); - this.rw = checkNotNull(rw); - this.inserter = checkNotNull(inserter); - inserterWrapper = new NonFlushingInserter(inserter); - commands = new ChainedReceiveCommands(repo); - closeRepo = false; - } - - /** - * Get this repo's configuration. - * - * <p>This is the storage-level config you would get with {@link Repository#getConfig()}, not, for - * example, the Gerrit-level project config. - * - * @return a defensive copy of the config; modifications have no effect on the underlying config. - */ - public Config getConfig() { - return new Config(repo.getConfig()); - } - - /** - * Get an open revwalk on the repo. - * - * <p>Guaranteed to be able to read back any objects inserted in the repository via {@link - * RepoContext#getInserter()}, even if objects have not been flushed to the underlying repo. In - * particular this includes any object returned by {@link #getRef(String)}, even taking into - * account not-yet-executed commands. - * - * @return revwalk. - */ - public RevWalk getRevWalk() { - return rw; - } - - /** - * Read a single ref from the repo. - * - * <p>Takes into account any ref update commands added during the course of the update using - * {@link RepoContext#addRefUpdate}, even if they have not yet been executed on the underlying - * repo. - * - * <p>The results of individual ref lookups are cached: calling this method multiple times with - * the same ref name will return the same result (unless a command was added in the meantime). The - * repo is not reread. - * - * @param name exact ref name. - * @return the value of the ref, if present. - * @throws IOException if an error occurred. - */ - public Optional<ObjectId> getRef(String name) throws IOException { - return getCommands().get(name); - } - - /** - * Look up refs by prefix. - * - * <p>Takes into account any ref update commands added during the course of the update using - * {@link RepoContext#addRefUpdate}, even if they have not yet been executed on the underlying - * repo. - * - * <p>For any ref that has previously been accessed with {@link #getRef(String)}, the value in the - * result map will be that same cached value. Any refs that have <em>not</em> been previously - * accessed are re-scanned from the repo on each call. - * - * @param prefix ref prefix; must end in '/' or else be empty. - * @return a map of ref suffixes to SHA-1s. The refs are all under {@code prefix} and have the - * prefix stripped; this matches the behavior of {@link - * org.eclipse.jgit.lib.RefDatabase#getRefs(String)}. - * @throws IOException if an error occurred. - */ - public Map<String, ObjectId> getRefs(String prefix) throws IOException { - Map<String, ObjectId> result = - new HashMap<>( - Maps.transformValues(repo.getRefDatabase().getRefs(prefix), Ref::getObjectId)); - - // First, overwrite any cached reads from the underlying RepoRefCache. If any of these differ, - // it's because a ref was updated after the RepoRefCache read it. It feels a little odd to - // prefer the *old* value in this case, but it would be weirder to be inconsistent with getRef. - // - // Mostly this doesn't matter. If the caller was intending to write to the ref, they lost a - // race, and they will get a lock failure. If they just want to read, well, the JGit interface - // doesn't currently guarantee that any snapshot of multiple refs is consistent, so they were - // probably out of luck anyway. - commands - .getRepoRefCache() - .getCachedRefs() - .forEach((k, v) -> updateRefIfPrefixMatches(result, prefix, k, v)); - - // Second, overwrite with any pending commands. - commands - .getCommands() - .values() - .forEach( - c -> - updateRefIfPrefixMatches(result, prefix, c.getRefName(), toOptional(c.getNewId()))); - - return result; - } - - private static Optional<ObjectId> toOptional(ObjectId id) { - return id.equals(ObjectId.zeroId()) ? Optional.empty() : Optional.of(id); - } - - private static void updateRefIfPrefixMatches( - Map<String, ObjectId> map, String prefix, String fullRefName, Optional<ObjectId> maybeId) { - if (!fullRefName.startsWith(prefix)) { - return; - } - String suffix = fullRefName.substring(prefix.length()); - if (maybeId.isPresent()) { - map.put(suffix, maybeId.get()); - } else { - map.remove(suffix); - } - } - - // Not AutoCloseable so callers can't improperly close it. Plus it's never managed with a try - // block anyway. - void close() { - if (closeRepo) { - inserter.close(); - rw.close(); - repo.close(); - } - } - - Repository getRepository() { - return repo; - } - - ObjectInserter getInserter() { - return inserter; - } - - ObjectInserter getInserterWrapper() { - return inserterWrapper; - } - - ChainedReceiveCommands getCommands() { - return commands; - } - - private static class NonFlushingInserter extends ObjectInserter.Filter { - private final ObjectInserter delegate; - - private NonFlushingInserter(ObjectInserter delegate) { - this.delegate = delegate; - } - - @Override - protected ObjectInserter delegate() { - return delegate; - } - - @Override - public void flush() { - // Do nothing. - } - - @Override - public void close() { - // Do nothing; the delegate is closed separately. - } - } -} |