/**
* 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.falcon.security;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.security.auth.Subject;
/**
* Current authenticated user via REST.
*/
public final class CurrentUser {
private static final Logger LOG = LoggerFactory.getLogger(CurrentUser.class);
private static final CurrentUser INSTANCE = new CurrentUser();
private CurrentUser() {}
public static CurrentUser get() {
return INSTANCE;
}
private final ThreadLocal<Subject> currentSubject = new ThreadLocal<Subject>();
public static void authenticate(String user) {
if (user == null || user.isEmpty()) {
throw new IllegalStateException("Bad user name sent for authentication");
}
if (user.equals(getUserInternal())) {
return;
}
Subject subject = new Subject();
subject.getPrincipals().add(new FalconPrincipal(user));
LOG.info("Logging in {}", user);
INSTANCE.currentSubject.set(subject);
}
public static Subject getSubject() {
return INSTANCE.currentSubject.get();
}
public static String getUser() {
String user = getUserInternal();
if (user == null) {
throw new IllegalStateException("No user logged into the system");
} else {
return user;
}
}
private static String getUserInternal() {
Subject subject = getSubject();
if (subject == null) {
return null;
} else {
for (FalconPrincipal principal : subject.
getPrincipals(FalconPrincipal.class)) {
return principal.getName();
}
return null;
}
}
}