// Copyright (C) 2009 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 com.google.gerrit.reviewdb.client.CurrentSchemaVersion;
import com.google.gerrit.reviewdb.server.ReviewDb;
import com.google.gwtorm.jdbc.JdbcExecutor;
import com.google.gwtorm.jdbc.JdbcSchema;
import com.google.gwtorm.server.OrmException;
import com.google.gwtorm.server.StatementExecutor;
import com.google.inject.AbstractModule;
import com.google.inject.Provider;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/** A version of the database schema. */
public abstract class SchemaVersion {
/** The current schema version. */
public static final Class<Schema_69> C = Schema_69.class;
public static class Module extends AbstractModule {
@Override
protected void configure() {
bind(SchemaVersion.class).annotatedWith(Current.class).to(C);
}
}
private final Provider<? extends SchemaVersion> prior;
private final int versionNbr;
protected SchemaVersion(final Provider<? extends SchemaVersion> prior) {
this.prior = prior;
this.versionNbr = guessVersion(getClass());
}
private static int guessVersion(Class<?> c) {
String n = c.getName();
n = n.substring(n.lastIndexOf('_') + 1);
while (n.startsWith("0"))
n = n.substring(1);
return Integer.parseInt(n);
}
protected SchemaVersion(final Provider<? extends SchemaVersion> prior,
final int versionNbr) {
this.prior = prior;
this.versionNbr = versionNbr;
}
/** @return the {@link CurrentSchemaVersion#versionNbr} this step targets. */
public final int getVersionNbr() {
return versionNbr;
}
public final void check(UpdateUI ui, CurrentSchemaVersion curr, ReviewDb db, boolean toTargetVersion)
throws OrmException, SQLException {
if (curr.versionNbr == versionNbr) {
// Nothing to do, we are at the correct schema.
//
} else {
upgradeFrom(ui, curr, db, toTargetVersion);
}
}
/** Runs check on the prior schema version, and then upgrades. */
protected void upgradeFrom(UpdateUI ui, CurrentSchemaVersion curr, ReviewDb db, boolean toTargetVersion)
throws OrmException, SQLException {
final JdbcSchema s = (JdbcSchema) db;
prior.get().check(ui, curr, db, false);
ui.message("Upgrading database schema from version " + curr.versionNbr
+ " to " + versionNbr + " ...");
preUpdateSchema(db);
final JdbcExecutor e = new JdbcExecutor(s);
try {
s.updateSchema(e);
migrateData(db, ui);
if (toTargetVersion) {
final List<String> pruneList = new ArrayList<String>();
s.pruneSchema(new StatementExecutor() {
public void execute(String sql) {
pruneList.add(sql);
}
});
if (!pruneList.isEmpty()) {
ui.pruneSchema(e, pruneList);
}
}
} finally {
e.close();
}
finish(curr, db);
}
/** Invoke before updateSchema adds new columns/tables. */
protected void preUpdateSchema(ReviewDb db) throws OrmException, SQLException {
}
/**
* Invoked between updateSchema (adds new columns/tables) and pruneSchema
* (removes deleted columns/tables).
*/
protected void migrateData(ReviewDb db, UpdateUI ui) throws OrmException, SQLException {
}
/** Mark the current schema version. */
protected void finish(CurrentSchemaVersion curr, ReviewDb db)
throws OrmException {
curr.versionNbr = versionNbr;
db.schemaVersion().update(Collections.singleton(curr));
}
/** Rename an existing column. */
protected void renameColumn(ReviewDb db, String table, String from, String to)
throws OrmException {
final JdbcSchema s = (JdbcSchema) db;
final JdbcExecutor e = new JdbcExecutor(s);
try {
s.renameField(e, table, from, to);
} finally {
e.close();
}
}
/** Execute a SQL statement. */
protected void execute(ReviewDb db, String sql) throws SQLException {
Statement s = ((JdbcSchema) db).getConnection().createStatement();
try {
s.execute(sql);
} finally {
s.close();
}
}
}