com.facebook.presto.example.ExampleMetadata Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of presto-example-http Show documentation
Show all versions of presto-example-http Show documentation
Presto - Example HTTP Connector
The newest version!
/*
* 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.example;
import com.facebook.presto.spi.ColumnHandle;
import com.facebook.presto.spi.ColumnMetadata;
import com.facebook.presto.spi.ConnectorSession;
import com.facebook.presto.spi.ConnectorTableHandle;
import com.facebook.presto.spi.ConnectorTableLayout;
import com.facebook.presto.spi.ConnectorTableLayoutHandle;
import com.facebook.presto.spi.ConnectorTableLayoutResult;
import com.facebook.presto.spi.ConnectorTableMetadata;
import com.facebook.presto.spi.Constraint;
import com.facebook.presto.spi.SchemaTableName;
import com.facebook.presto.spi.SchemaTablePrefix;
import com.facebook.presto.spi.TableNotFoundException;
import com.facebook.presto.spi.connector.ConnectorMetadata;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import javax.inject.Inject;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import static com.google.common.base.Preconditions.checkArgument;
import static java.util.Objects.requireNonNull;
public class ExampleMetadata
implements ConnectorMetadata
{
private final String connectorId;
private final ExampleClient exampleClient;
@Inject
public ExampleMetadata(ExampleConnectorId connectorId, ExampleClient exampleClient)
{
this.connectorId = requireNonNull(connectorId, "connectorId is null").toString();
this.exampleClient = requireNonNull(exampleClient, "client is null");
}
@Override
public List listSchemaNames(ConnectorSession session)
{
return listSchemaNames();
}
public List listSchemaNames()
{
return ImmutableList.copyOf(exampleClient.getSchemaNames());
}
@Override
public ExampleTableHandle getTableHandle(ConnectorSession session, SchemaTableName tableName)
{
if (!listSchemaNames(session).contains(tableName.getSchemaName())) {
return null;
}
ExampleTable table = exampleClient.getTable(tableName.getSchemaName(), tableName.getTableName());
if (table == null) {
return null;
}
return new ExampleTableHandle(connectorId, tableName.getSchemaName(), tableName.getTableName());
}
@Override
public List getTableLayouts(ConnectorSession session, ConnectorTableHandle table, Constraint constraint, Optional> desiredColumns)
{
ExampleTableHandle tableHandle = (ExampleTableHandle) table;
ConnectorTableLayout layout = new ConnectorTableLayout(new ExampleTableLayoutHandle(tableHandle));
return ImmutableList.of(new ConnectorTableLayoutResult(layout, constraint.getSummary()));
}
@Override
public ConnectorTableLayout getTableLayout(ConnectorSession session, ConnectorTableLayoutHandle handle)
{
return new ConnectorTableLayout(handle);
}
@Override
public ConnectorTableMetadata getTableMetadata(ConnectorSession session, ConnectorTableHandle table)
{
ExampleTableHandle exampleTableHandle = (ExampleTableHandle) table;
checkArgument(exampleTableHandle.getConnectorId().equals(connectorId), "tableHandle is not for this connector");
SchemaTableName tableName = new SchemaTableName(exampleTableHandle.getSchemaName(), exampleTableHandle.getTableName());
return getTableMetadata(tableName);
}
@Override
public List listTables(ConnectorSession session, String schemaNameOrNull)
{
Set schemaNames;
if (schemaNameOrNull != null) {
schemaNames = ImmutableSet.of(schemaNameOrNull);
}
else {
schemaNames = exampleClient.getSchemaNames();
}
ImmutableList.Builder builder = ImmutableList.builder();
for (String schemaName : schemaNames) {
for (String tableName : exampleClient.getTableNames(schemaName)) {
builder.add(new SchemaTableName(schemaName, tableName));
}
}
return builder.build();
}
@Override
public Map getColumnHandles(ConnectorSession session, ConnectorTableHandle tableHandle)
{
ExampleTableHandle exampleTableHandle = (ExampleTableHandle) tableHandle;
checkArgument(exampleTableHandle.getConnectorId().equals(connectorId), "tableHandle is not for this connector");
ExampleTable table = exampleClient.getTable(exampleTableHandle.getSchemaName(), exampleTableHandle.getTableName());
if (table == null) {
throw new TableNotFoundException(exampleTableHandle.toSchemaTableName());
}
ImmutableMap.Builder columnHandles = ImmutableMap.builder();
int index = 0;
for (ColumnMetadata column : table.getColumnsMetadata()) {
columnHandles.put(column.getName(), new ExampleColumnHandle(connectorId, column.getName(), column.getType(), index));
index++;
}
return columnHandles.build();
}
@Override
public Map> listTableColumns(ConnectorSession session, SchemaTablePrefix prefix)
{
requireNonNull(prefix, "prefix is null");
ImmutableMap.Builder> columns = ImmutableMap.builder();
for (SchemaTableName tableName : listTables(session, prefix)) {
ConnectorTableMetadata tableMetadata = getTableMetadata(tableName);
// table can disappear during listing operation
if (tableMetadata != null) {
columns.put(tableName, tableMetadata.getColumns());
}
}
return columns.build();
}
private ConnectorTableMetadata getTableMetadata(SchemaTableName tableName)
{
if (!listSchemaNames().contains(tableName.getSchemaName())) {
return null;
}
ExampleTable table = exampleClient.getTable(tableName.getSchemaName(), tableName.getTableName());
if (table == null) {
return null;
}
return new ConnectorTableMetadata(tableName, table.getColumnsMetadata());
}
private List listTables(ConnectorSession session, SchemaTablePrefix prefix)
{
if (prefix.getSchemaName() == null) {
return listTables(session, prefix.getSchemaName());
}
return ImmutableList.of(new SchemaTableName(prefix.getSchemaName(), prefix.getTableName()));
}
@Override
public ColumnMetadata getColumnMetadata(ConnectorSession session, ConnectorTableHandle tableHandle, ColumnHandle columnHandle)
{
return ((ExampleColumnHandle) columnHandle).getColumnMetadata();
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy