/*
* The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
* (the "License"). You may not use this work except in compliance with the License, which is
* available at www.apache.org/licenses/LICENSE-2.0
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
* either express or implied, as more fully set forth in the License.
*
* See the NOTICE file distributed with this work for information regarding copyright ownership.
*/
package alluxio.security.group.provider;
import alluxio.security.group.GroupMappingService;
import alluxio.util.CommonUtils;
import java.io.IOException;
import java.util.ArrayList;
import java.util.LinkedHashSet;
import java.util.List;
/**
* A simple shell-based implementation of {@link GroupMappingService} that exec's the {@code groups}
* shell command to fetch the group memberships of a given user.
*/
public final class ShellBasedUnixGroupsMapping implements GroupMappingService {
/**
* Constructs a new {@link ShellBasedUnixGroupsMapping}.
*/
public ShellBasedUnixGroupsMapping() {}
/**
* Returns list of groups for a user.
*
* @param user get groups for this user
* @return list of groups for a given user
*/
@Override
public List<String> getGroups(String user) throws IOException {
List<String> groups = CommonUtils.getUnixGroups(user);
// remove duplicated primary group
return new ArrayList<>(new LinkedHashSet<>(groups));
}
}