opendev/gerrit
Code Issues Proposed changes

Store NoteDb migration state inside Change

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Since a ReviewDb write might succeed but its corresponding NoteDb
write might fail, we would like to be able to detect and fix up such
problems after the fact. The most reliable way to do so is to store,
somewhere, the complete set of ref state across the change meta repo
and All-Users for a given Change entity. This effectively needs to
be in Change, or at least in ReviewDb, so that we can write it in the
same transaction that stores the rest of the Change mutation.

Split up NoteDbUpdateManager into two phases, "stage" and "execute".
Stage the change before committing the ReviewDb transaction, and use
the results of staging to update the noteDbState field in Change.

The state is abstracted as an immutable data type NoteDbChangeState,
and NoteDbUpdateManager computes a "Delta" over the type. This
abstraction helps with compile-time safety and testability. However,
for simplicity in the Change record, we just serialize the results
into a simple, parsimonious string.

Change-Id: I2cccda1ccb54062aa1e80ecc82994614ef6d9598
This commit is contained in:
Dave Borowitz
2016-03-25 14:00:55 -04:00
parent f71b304786
commit 790103c4b1
12 changed files with 637 additions and 18 deletions
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156
gerrit-server/src/test/java/com/google/gerrit/server/notedb/NoteDbChangeStateTest.java Normal file
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// Copyright (C) 2016 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 static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.truth.Truth.assertThat;
import static com.google.gerrit.server.notedb.NoteDbChangeState.applyDelta;
import static com.google.gerrit.server.notedb.NoteDbChangeState.parse;
import static org.eclipse.jgit.lib.ObjectId.zeroId;
import com.google.common.base.Optional;
import com.google.common.collect.ImmutableMap;
import com.google.gerrit.reviewdb.client.Account;
import com.google.gerrit.reviewdb.client.Change;
import com.google.gerrit.reviewdb.client.Project;
import com.google.gerrit.server.notedb.NoteDbChangeState.Delta;
import com.google.gerrit.testutil.TestChanges;
import com.google.gwtorm.client.KeyUtil;
import com.google.gwtorm.server.StandardKeyEncoder;
import org.eclipse.jgit.lib.ObjectId;
import org.junit.Test;
/** Unit tests for {@link NoteDbChangeState}. */
public class NoteDbChangeStateTest {
static {
KeyUtil.setEncoderImpl(new StandardKeyEncoder());
}
ObjectId SHA1 =
ObjectId.fromString("deadbeefdeadbeefdeadbeefdeadbeefdeadbeef");
ObjectId SHA2 =
ObjectId.fromString("abcd1234abcd1234abcd1234abcd1234abcd1234");
ObjectId SHA3 =
ObjectId.fromString("badc0feebadc0feebadc0feebadc0feebadc0fee");
@Test
public void parseWithoutDrafts() {
NoteDbChangeState state = parse(new Change.Id(1), SHA1.name());
assertThat(state.getChangeId()).isEqualTo(new Change.Id(1));
assertThat(state.getChangeMetaId()).isEqualTo(SHA1);
assertThat(state.getDraftIds()).isEmpty();
assertThat(state.toString()).isEqualTo(SHA1.name());
}
@Test
public void parseWithDrafts() {
NoteDbChangeState state = parse(
new Change.Id(1),
SHA1.name() + ",2003=" + SHA2.name() + ",1001=" + SHA3.name());
assertThat(state.getChangeId()).isEqualTo(new Change.Id(1));
assertThat(state.getChangeMetaId()).isEqualTo(SHA1);
assertThat(state.getDraftIds()).containsExactly(
new Account.Id(1001), SHA3,
new Account.Id(2003), SHA2);
assertThat(state.toString()).isEqualTo(
SHA1.name() + ",1001=" + SHA3.name() + ",2003=" + SHA2.name());
}
@Test
public void applyDeltaToNullWithNoNewMetaId() {
Change c = newChange();
assertThat(c.getNoteDbState()).isNull();
applyDelta(c, Delta.create(c.getId(), noMetaId(), noDrafts()));
assertThat(c.getNoteDbState()).isNull();
applyDelta(c, Delta.create(c.getId(), noMetaId(),
drafts(new Account.Id(1001), zeroId())));
assertThat(c.getNoteDbState()).isNull();
}
@Test
public void applyDeltaToMetaId() {
Change c = newChange();
applyDelta(c, Delta.create(c.getId(), metaId(SHA1), noDrafts()));
assertThat(c.getNoteDbState()).isEqualTo(SHA1.name());
applyDelta(c, Delta.create(c.getId(), metaId(SHA2), noDrafts()));
assertThat(c.getNoteDbState()).isEqualTo(SHA2.name());
// No-op delta.
applyDelta(c, Delta.create(c.getId(), noMetaId(), noDrafts()));
assertThat(c.getNoteDbState()).isEqualTo(SHA2.name());
// Set to zero clears the field.
applyDelta(c, Delta.create(c.getId(), metaId(zeroId()), noDrafts()));
assertThat(c.getNoteDbState()).isNull();
}
@Test
public void applyDeltaToDrafts() {
Change c = newChange();
applyDelta(c, Delta.create(c.getId(), metaId(SHA1),
drafts(new Account.Id(1001), SHA2)));
assertThat(c.getNoteDbState()).isEqualTo(
SHA1.name() + ",1001=" + SHA2.name());
applyDelta(c, Delta.create(c.getId(), noMetaId(),
drafts(new Account.Id(2003), SHA3)));
assertThat(c.getNoteDbState()).isEqualTo(
SHA1.name() + ",1001=" + SHA2.name() + ",2003=" + SHA3.name());
applyDelta(c, Delta.create(c.getId(), noMetaId(),
drafts(new Account.Id(2003), zeroId())));
assertThat(c.getNoteDbState()).isEqualTo(
SHA1.name() + ",1001=" + SHA2.name());
applyDelta(c, Delta.create(c.getId(), metaId(SHA3), noDrafts()));
assertThat(c.getNoteDbState()).isEqualTo(
SHA3.name() + ",1001=" + SHA2.name());
}
private static Change newChange() {
return TestChanges.newChange(
new Project.NameKey("project"), new Account.Id(12345));
}
// Static factory methods to avoid type arguments when using as method args.
private static Optional<ObjectId> noMetaId() {
return Optional.absent();
}
private static Optional<ObjectId> metaId(ObjectId id) {
return Optional.of(id);
}
private static ImmutableMap<Account.Id, ObjectId> noDrafts() {
return ImmutableMap.of();
}
private static ImmutableMap<Account.Id, ObjectId> drafts(Object... args) {
checkArgument(args.length % 2 == 0);
ImmutableMap.Builder<Account.Id, ObjectId> b = ImmutableMap.builder();
for (int i = 0; i < args.length / 2; i++) {
b.put((Account.Id) args[2*i], (ObjectId) args[2*i+1]);
}
return b.build();
}
}