com.google.gerrit.server.notedb.MutableNotesMigration Maven / Gradle / Ivy
// 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.notedb;
import com.google.gerrit.server.config.GerritServerConfig;
import com.google.gerrit.server.notedb.NoteDbChangeState.PrimaryStorage;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import java.util.function.Function;
import org.eclipse.jgit.lib.Config;
/**
* {@link NotesMigration} with additional methods for altering the migration state at runtime.
*
* Almost all callers care only about inspecting the migration state, and for safety should not
* have access to mutation methods, which must be used with extreme care. Those callers should
* inject {@link NotesMigration}.
*
*
Some callers, namely the NoteDb migration pipeline and tests, do need to alter the migration
* state at runtime, and those callers are expected to take the necessary precautions such as
* keeping the in-memory and on-disk config state in sync. Those callers use this class.
*
*
Mutations to the {@link MutableNotesMigration} are guaranteed to be instantly visible to all
* callers that use the non-mutable {@link NotesMigration}. The current implementation accomplishes
* this by always binding {@link NotesMigration} to {@link MutableNotesMigration} in Guice, so there
* is just one {@link NotesMigration} instance process-wide.
*/
@Singleton
public class MutableNotesMigration extends NotesMigration {
public static MutableNotesMigration newDisabled() {
return new MutableNotesMigration(new Config());
}
public static MutableNotesMigration fromConfig(Config cfg) {
return new MutableNotesMigration(cfg);
}
@Inject
MutableNotesMigration(@GerritServerConfig Config cfg) {
super(Snapshot.create(cfg));
}
public MutableNotesMigration setReadChanges(boolean readChanges) {
return set(b -> b.setReadChanges(readChanges));
}
public MutableNotesMigration setWriteChanges(boolean writeChanges) {
return set(b -> b.setWriteChanges(writeChanges));
}
public MutableNotesMigration setReadChangeSequence(boolean readChangeSequence) {
return set(b -> b.setReadChangeSequence(readChangeSequence));
}
public MutableNotesMigration setChangePrimaryStorage(PrimaryStorage changePrimaryStorage) {
return set(b -> b.setChangePrimaryStorage(changePrimaryStorage));
}
public MutableNotesMigration setDisableChangeReviewDb(boolean disableChangeReviewDb) {
return set(b -> b.setDisableChangeReviewDb(disableChangeReviewDb));
}
public MutableNotesMigration setFailOnLoadForTest(boolean failOnLoadForTest) {
return set(b -> b.setFailOnLoadForTest(failOnLoadForTest));
}
/**
* Set the in-memory values returned by this instance to match the given state.
*
*
This method is only intended for use by {@link
* com.google.gerrit.server.notedb.rebuild.NoteDbMigrator}.
*
*
This only modifies the in-memory state; if this instance was initialized from a
* file-based config, the underlying storage is not updated. Callers are responsible for managing
* the underlying storage on their own.
*/
public MutableNotesMigration setFrom(NotesMigrationState state) {
snapshot.set(state.snapshot());
return this;
}
/** @see #setFrom(NotesMigrationState) */
public MutableNotesMigration setFrom(NotesMigration other) {
snapshot.set(other.snapshot.get());
return this;
}
private MutableNotesMigration set(Function f) {
snapshot.updateAndGet(s -> f.apply(s.toBuilder()).build());
return this;
}
}