/*
* 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.facebook.presto.execution;
import com.facebook.presto.metadata.Metadata;
import com.facebook.presto.metadata.QualifiedTableName;
import com.facebook.presto.metadata.ViewDefinition;
import com.facebook.presto.spi.ConnectorSession;
import com.facebook.presto.spi.PrestoException;
import com.facebook.presto.sql.analyzer.Analysis;
import com.facebook.presto.sql.analyzer.Analyzer;
import com.facebook.presto.sql.analyzer.FeaturesConfig;
import com.facebook.presto.sql.analyzer.Field;
import com.facebook.presto.sql.analyzer.QueryExplainer;
import com.facebook.presto.sql.parser.ParsingException;
import com.facebook.presto.sql.parser.SqlParser;
import com.facebook.presto.sql.planner.optimizations.PlanOptimizer;
import com.facebook.presto.sql.tree.CreateView;
import com.facebook.presto.sql.tree.Query;
import com.facebook.presto.sql.tree.Statement;
import com.google.common.base.Function;
import com.google.common.base.Optional;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.ImmutableList;
import io.airlift.json.JsonCodec;
import javax.inject.Inject;
import java.util.List;
import static com.facebook.presto.metadata.MetadataUtil.createQualifiedTableName;
import static com.facebook.presto.metadata.ViewDefinition.ViewColumn;
import static com.facebook.presto.spi.StandardErrorCode.INTERNAL_ERROR;
import static com.facebook.presto.sql.SqlFormatter.formatSql;
import static com.google.common.base.Preconditions.checkNotNull;
public class CreateViewTask
implements DataDefinitionTask<CreateView>
{
private final JsonCodec<ViewDefinition> codec;
private final SqlParser sqlParser;
private final List<PlanOptimizer> planOptimizers;
private final boolean experimentalSyntaxEnabled;
@Inject
public CreateViewTask(JsonCodec<ViewDefinition> codec, SqlParser sqlParser, List<PlanOptimizer> planOptimizers, FeaturesConfig featuresConfig)
{
this.codec = checkNotNull(codec, "codec is null");
this.sqlParser = checkNotNull(sqlParser, "sqlParser is null");
this.planOptimizers = ImmutableList.copyOf(checkNotNull(planOptimizers, "planOptimizers is null"));
this.experimentalSyntaxEnabled = checkNotNull(featuresConfig, "featuresConfig is null").isExperimentalSyntaxEnabled();
}
@Override
public void execute(CreateView statement, ConnectorSession session, Metadata metadata)
{
QualifiedTableName name = createQualifiedTableName(session, statement.getName());
String sql = getFormattedSql(statement);
Analysis analysis = analyzeStatement(statement, session, metadata);
Iterable<Field> fields = analysis.getOutputDescriptor().getVisibleFields();
List<ViewColumn> columns = FluentIterable.from(fields).transform(fieldToColumn()).toList();
String data = codec.toJson(new ViewDefinition(sql, session.getCatalog(), session.getSchema(), columns));
metadata.createView(session, name, data, statement.isReplace());
}
public Analysis analyzeStatement(Statement statement, ConnectorSession session, Metadata metadata)
{
QueryExplainer explainer = new QueryExplainer(session, planOptimizers, metadata, sqlParser, experimentalSyntaxEnabled);
Analyzer analyzer = new Analyzer(session, metadata, sqlParser, Optional.of(explainer), experimentalSyntaxEnabled);
return analyzer.analyze(statement);
}
private static Function<Field, ViewColumn> fieldToColumn()
{
return new Function<Field, ViewColumn>()
{
@Override
public ViewColumn apply(Field field)
{
return new ViewColumn(field.getName().get(), field.getType());
}
};
}
private String getFormattedSql(CreateView statement)
{
Query query = statement.getQuery();
String sql = formatSql(query);
// verify round-trip
Statement parsed;
try {
parsed = sqlParser.createStatement(sql);
}
catch (ParsingException e) {
throw new PrestoException(INTERNAL_ERROR.toErrorCode(), "Formatted query does not parse: " + query);
}
if (!query.equals(parsed)) {
throw new PrestoException(INTERNAL_ERROR.toErrorCode(), "Query does not round-trip: " + query);
}
return sql;
}
}