/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.lens.lib.query;

import java.io.IOException;
import java.security.PrivilegedExceptionAction;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.security.UserGroupInformation;

import lombok.extern.slf4j.Slf4j;

@Slf4j
public class FileSystemUtil {

  private FileSystemUtil() {}

  public static FileSystem createFileSystem(String proxyUser, Path path) {
    try {
      UserGroupInformation ugi = UserGroupInformation.createProxyUser(proxyUser, UserGroupInformation.getLoginUser());
      return ugi.doAs((PrivilegedExceptionAction<FileSystem>) () -> open(path));
    } catch (IOException e) {
      log.error("error initializing filesystem, giving up leadership", e);
      throw new RuntimeException(e);
    } catch (InterruptedException e) {
      log.error("interrupted while initializing filesystem, giving up leadership", e);
      throw new RuntimeException(e);
    }
  }

  public static FileSystem open(Path filePath) throws IOException {
    Configuration conf = new Configuration();
    conf.setBoolean("fs.automatic.close", false);
    return filePath.getFileSystem(conf);
  }

}