// Copyright 2009 Google Inc.
//
// 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.
import com.google.visualization.datasource.Capabilities;
import com.google.visualization.datasource.DataSourceServlet;
import com.google.visualization.datasource.base.DataSourceException;
import com.google.visualization.datasource.datatable.DataTable;
import com.google.visualization.datasource.query.Query;
import com.google.visualization.datasource.util.SqlDataSourceHelper;
import com.google.visualization.datasource.util.SqlDatabaseDescription;
import javax.servlet.http.HttpServletRequest;
/**
* An example data source servlet that can query an SQL database.
* This makes use of the SqlDataSourceHelper class that is part of this library.
*
* Query language operations affect the result. This includes operations
* that are not part of SQL itself, such as pivoting, which is executed by
* the query engine.
*
* Four URL parameters must be specified, these are then passed to
* the underlying SQL DB. The parameters are as follows:
* url - The url of the sql DB.
* user - The username to use when accessing the DB.
* password - The password to use when accessing the DB.
* table - The SQL table name.
*
* @author Yaniv S.
*/
public class SqlDataSourceServlet extends DataSourceServlet {
/**
* The SQL predefined capabilities set is a special custom set for SQL
* databases. This implements most of the data source capabilities more
* efficiently.
*/
@Override
public Capabilities getCapabilities() {
return Capabilities.SQL;
}
@Override
public DataTable generateDataTable(Query query, HttpServletRequest request)
throws DataSourceException {
SqlDatabaseDescription dbDescription = new SqlDatabaseDescription(
request.getParameter("url"),
request.getParameter("user"),
request.getParameter("password"),
request.getParameter("table"));
return SqlDataSourceHelper.executeQuery(query, dbDescription);
}
/**
* NOTE: By default, this function returns true, which means that cross
* domain requests are rejected.
* This check is disabled here so examples can be used directly from the
* address bar of the browser. Bear in mind that this exposes your
* data source to xsrf attacks.
* If the only use of the data source url is from your application,
* that runs on the same domain, it is better to remain in restricted mode.
*/
@Override
protected boolean isRestrictedAccessMode() {
return false;
}
}