// 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.schema;
import static com.google.common.base.Preconditions.checkState;
import com.google.common.collect.ImmutableList;
import com.google.common.util.concurrent.CheckedFuture;
import com.google.common.util.concurrent.Futures;
import com.google.gerrit.reviewdb.client.Account;
import com.google.gerrit.reviewdb.client.Change;
import com.google.gerrit.reviewdb.client.ChangeMessage;
import com.google.gerrit.reviewdb.client.PatchLineComment;
import com.google.gerrit.reviewdb.client.PatchSet;
import com.google.gerrit.reviewdb.client.PatchSetApproval;
import com.google.gerrit.reviewdb.server.ChangeAccess;
import com.google.gerrit.reviewdb.server.ChangeMessageAccess;
import com.google.gerrit.reviewdb.server.PatchLineCommentAccess;
import com.google.gerrit.reviewdb.server.PatchSetAccess;
import com.google.gerrit.reviewdb.server.PatchSetApprovalAccess;
import com.google.gerrit.reviewdb.server.ReviewDb;
import com.google.gerrit.reviewdb.server.ReviewDbWrapper;
import com.google.gwtorm.client.Key;
import com.google.gwtorm.server.Access;
import com.google.gwtorm.server.AtomicUpdate;
import com.google.gwtorm.server.ListResultSet;
import com.google.gwtorm.server.OrmException;
import com.google.gwtorm.server.ResultSet;
import java.util.Map;
import java.util.function.Function;
/**
* Wrapper for ReviewDb that never calls the underlying change tables.
*
* <p>See {@link NotesMigrationSchemaFactory} for discussion.
*/
class NoChangesReviewDbWrapper extends ReviewDbWrapper {
private static <T> ResultSet<T> empty() {
return new ListResultSet<>(ImmutableList.of());
}
private static <T, K extends Key<?>> CheckedFuture<T, OrmException> emptyFuture() {
return Futures.immediateCheckedFuture(null);
}
private final ChangeAccess changes;
private final PatchSetApprovalAccess patchSetApprovals;
private final ChangeMessageAccess changeMessages;
private final PatchSetAccess patchSets;
private final PatchLineCommentAccess patchComments;
private boolean inTransaction;
NoChangesReviewDbWrapper(ReviewDb db) {
super(db);
changes = new Changes(this, delegate);
patchSetApprovals = new PatchSetApprovals(this, delegate);
changeMessages = new ChangeMessages(this, delegate);
patchSets = new PatchSets(this, delegate);
patchComments = new PatchLineComments(this, delegate);
}
@Override
public boolean changesTablesEnabled() {
return false;
}
@Override
public ChangeAccess changes() {
return changes;
}
@Override
public PatchSetApprovalAccess patchSetApprovals() {
return patchSetApprovals;
}
@Override
public ChangeMessageAccess changeMessages() {
return changeMessages;
}
@Override
public PatchSetAccess patchSets() {
return patchSets;
}
@Override
public PatchLineCommentAccess patchComments() {
return patchComments;
}
@Override
public void commit() throws OrmException {
if (!inTransaction) {
// This reads a little weird, we're not in a transaction, so why are we calling commit?
// Because we want to let the underlying ReviewDb do its normal thing in this case (which may
// be throwing an exception, or not, depending on implementation).
delegate.commit();
}
}
@Override
public void rollback() throws OrmException {
if (inTransaction) {
inTransaction = false;
} else {
// See comment in commit(): we want to let the underlying ReviewDb do its thing.
delegate.rollback();
}
}
private abstract static class AbstractDisabledAccess<T, K extends Key<?>>
implements Access<T, K> {
// Don't even hold a reference to delegate, so it's not possible to use it accidentally.
private final NoChangesReviewDbWrapper wrapper;
private final String relationName;
private final int relationId;
private final Function<T, K> primaryKey;
private final Function<Iterable<T>, Map<K, T>> toMap;
private AbstractDisabledAccess(NoChangesReviewDbWrapper wrapper, Access<T, K> delegate) {
this.wrapper = wrapper;
this.relationName = delegate.getRelationName();
this.relationId = delegate.getRelationID();
this.primaryKey = delegate::primaryKey;
this.toMap = delegate::toMap;
}
@Override
public final int getRelationID() {
return relationId;
}
@Override
public final String getRelationName() {
return relationName;
}
@Override
public final K primaryKey(T entity) {
return primaryKey.apply(entity);
}
@Override
public final Map<K, T> toMap(Iterable<T> iterable) {
return toMap.apply(iterable);
}
@Override
public final ResultSet<T> iterateAllEntities() {
return empty();
}
@Override
public final CheckedFuture<T, OrmException> getAsync(K key) {
return emptyFuture();
}
@Override
public final ResultSet<T> get(Iterable<K> keys) {
return empty();
}
@Override
public final void insert(Iterable<T> instances) {
// Do nothing.
}
@Override
public final void update(Iterable<T> instances) {
// Do nothing.
}
@Override
public final void upsert(Iterable<T> instances) {
// Do nothing.
}
@Override
public final void deleteKeys(Iterable<K> keys) {
// Do nothing.
}
@Override
public final void delete(Iterable<T> instances) {
// Do nothing.
}
@Override
public final void beginTransaction(K key) {
// Keep track of when we've started a transaction so that we can avoid calling commit/rollback
// on the underlying ReviewDb. This is just a simple arm's-length approach, and may produce
// slightly different results from a native ReviewDb in corner cases like:
// * beginning transactions on different tables simultaneously
// * doing work between commit and rollback
// These kinds of things are already misuses of ReviewDb, and shouldn't be happening in
// current code anyway.
checkState(!wrapper.inTransaction, "already in transaction");
wrapper.inTransaction = true;
}
@Override
public final T atomicUpdate(K key, AtomicUpdate<T> update) {
return null;
}
@Override
public final T get(K id) {
return null;
}
}
private static class Changes extends AbstractDisabledAccess<Change, Change.Id>
implements ChangeAccess {
private Changes(NoChangesReviewDbWrapper wrapper, ReviewDb db) {
super(wrapper, db.changes());
}
@Override
public ResultSet<Change> all() {
return empty();
}
}
private static class ChangeMessages
extends AbstractDisabledAccess<ChangeMessage, ChangeMessage.Key>
implements ChangeMessageAccess {
private ChangeMessages(NoChangesReviewDbWrapper wrapper, ReviewDb db) {
super(wrapper, db.changeMessages());
}
@Override
public ResultSet<ChangeMessage> byChange(Change.Id id) throws OrmException {
return empty();
}
@Override
public ResultSet<ChangeMessage> byPatchSet(PatchSet.Id id) throws OrmException {
return empty();
}
@Override
public ResultSet<ChangeMessage> all() throws OrmException {
return empty();
}
}
private static class PatchSets extends AbstractDisabledAccess<PatchSet, PatchSet.Id>
implements PatchSetAccess {
private PatchSets(NoChangesReviewDbWrapper wrapper, ReviewDb db) {
super(wrapper, db.patchSets());
}
@Override
public ResultSet<PatchSet> byChange(Change.Id id) {
return empty();
}
@Override
public ResultSet<PatchSet> all() {
return empty();
}
}
private static class PatchSetApprovals
extends AbstractDisabledAccess<PatchSetApproval, PatchSetApproval.Key>
implements PatchSetApprovalAccess {
private PatchSetApprovals(NoChangesReviewDbWrapper wrapper, ReviewDb db) {
super(wrapper, db.patchSetApprovals());
}
@Override
public ResultSet<PatchSetApproval> byChange(Change.Id id) {
return empty();
}
@Override
public ResultSet<PatchSetApproval> byPatchSet(PatchSet.Id id) {
return empty();
}
@Override
public ResultSet<PatchSetApproval> byPatchSetUser(PatchSet.Id patchSet, Account.Id account) {
return empty();
}
@Override
public ResultSet<PatchSetApproval> all() {
return empty();
}
}
private static class PatchLineComments
extends AbstractDisabledAccess<PatchLineComment, PatchLineComment.Key>
implements PatchLineCommentAccess {
private PatchLineComments(NoChangesReviewDbWrapper wrapper, ReviewDb db) {
super(wrapper, db.patchComments());
}
@Override
public ResultSet<PatchLineComment> byChange(Change.Id id) {
return empty();
}
@Override
public ResultSet<PatchLineComment> byPatchSet(PatchSet.Id id) {
return empty();
}
@Override
public ResultSet<PatchLineComment> publishedByChangeFile(Change.Id id, String file) {
return empty();
}
@Override
public ResultSet<PatchLineComment> publishedByPatchSet(PatchSet.Id patchset) {
return empty();
}
@Override
public ResultSet<PatchLineComment> draftByPatchSetAuthor(
PatchSet.Id patchset, Account.Id author) {
return empty();
}
@Override
public ResultSet<PatchLineComment> draftByChangeFileAuthor(
Change.Id id, String file, Account.Id author) {
return empty();
}
@Override
public ResultSet<PatchLineComment> draftByAuthor(Account.Id author) {
return empty();
}
@Override
public ResultSet<PatchLineComment> all() {
return empty();
}
}
}