fathom.realm.FileRealm Maven / Gradle / Ivy
/*
* Copyright (C) 2015 the original author or authors.
*
* 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 fathom.realm;
import com.google.common.base.Preconditions;
import com.google.common.base.Strings;
import com.typesafe.config.Config;
import com.typesafe.config.ConfigFactory;
import fathom.authc.AuthenticationToken;
import fathom.utils.Util;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
/**
* A FileRealm is a MemoryRealm that loads accounts and roles from an external file.
* The external file is watched and reloaded on modification.
*
* @author James Moger
*/
public class FileRealm extends MemoryRealm {
private static final Logger log = LoggerFactory.getLogger(FileRealm.class);
private volatile File realmFile;
private volatile long lastModified;
@Override
public void setup(Config config) {
super.setup(config);
String file = Strings.emptyToNull(config.getString("file"));
Preconditions.checkNotNull(file, "The [file] setting must be set!");
File realmFile = new File(file);
setFile(realmFile);
}
public void setFile(File realmFile) {
this.realmFile = realmFile;
readFile();
}
@Override
public void start() {
log.debug("Realm '{}' configuration:", getRealmName());
Util.logSetting(log, "file", realmFile);
}
/**
* Force a re-read of the credentials file (if modified) before executing authentication.
*
* @param authenticationToken
* @return the account if authentication is successful
*/
@Override
public Account authenticate(AuthenticationToken authenticationToken) {
readFile();
return super.authenticate(authenticationToken);
}
/**
* Reads the realm file and rebuilds the in-memory lookup tables.
*/
protected synchronized void readFile() {
if (realmFile != null && realmFile.exists() && (realmFile.lastModified() != lastModified)) {
lastModified = realmFile.lastModified();
try {
Preconditions.checkArgument(realmFile.canRead(), "The file '{}' can not be read!", realmFile);
Config config = ConfigFactory.parseFile(realmFile);
super.setup(config);
} catch (Exception e) {
log.error("Failed to read {}", realmFile, e);
}
}
}
}