zeroflag commented on code in PR #608: URL: https://github.com/apache/knox/pull/608#discussion_r924458961
########## gateway-util-common/src/main/java/org/apache/knox/gateway/util/ConcurrentSessionVerifier.java: ########## @@ -0,0 +1,79 @@ +/* + * 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.knox.gateway.util; + + +import java.util.HashSet; +import java.util.Map; +import java.util.Set; +import java.util.concurrent.ConcurrentHashMap; + +public class ConcurrentSessionVerifier { + private static Set<String> privilegedUsers = new HashSet<>(); + private static Set<String> nonPrivilegedUsers = new HashSet<>();; + private static int privilegedUserConcurrentSessionLimit = 3; + private static int nonPrivilegedUserConcurrentSessionLimit = 2; + private static Map<String, Integer> concurrentSessionCounter = new ConcurrentHashMap<>(); + private static final Object lock = new Object(); + + private ConcurrentSessionVerifier(){} + + public static synchronized void init(Set<String> privilegedUsers, Set<String> nonPrivilegedUsers, int privilegedUserConcurrentSessionLimit, int nonPrivilegedUserConcurrentSessionLimit){ + ConcurrentSessionVerifier.privilegedUsers = privilegedUsers; + ConcurrentSessionVerifier.nonPrivilegedUsers = nonPrivilegedUsers; + ConcurrentSessionVerifier.privilegedUserConcurrentSessionLimit = privilegedUserConcurrentSessionLimit; + ConcurrentSessionVerifier.nonPrivilegedUserConcurrentSessionLimit = nonPrivilegedUserConcurrentSessionLimit; + concurrentSessionCounter = new ConcurrentHashMap<>(); + } + + public static boolean verifySessionForUser(String username){ + if(!privilegedUsers.contains(username) && !nonPrivilegedUsers.contains(username)) { + return true; + } + synchronized(lock) { + if (!concurrentSessionCounter.containsKey(username)) { Review Comment: This is probably can be simplified by using `computeIfAbsent` / `putIfAbsent` / `compute` methods. For example: ```java int count = concurrentSessionCounter.computeIfAbsent(username, name -> 0); if (...) { } ``` ########## gateway-util-common/src/main/java/org/apache/knox/gateway/util/ConcurrentSessionVerifier.java: ########## @@ -0,0 +1,79 @@ +/* + * 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.knox.gateway.util; + + +import java.util.HashSet; +import java.util.Map; +import java.util.Set; +import java.util.concurrent.ConcurrentHashMap; + +public class ConcurrentSessionVerifier { Review Comment: Instead of using static methods and static fields, let's have a normal non static class with instance variables and non static methods. Constants like `privilegedUserConcurrentSessionLimit`/`privilegedUserConcurrentSessionLimit` should be kept as statics but `concurrentSessionCounter` should be non static. Then we can create one instance of this class and use that at each places where needed. Either by creating an instance somewhere in GatewayServer's `main()` and passing that around or by making a singleton. I prefer the former but that's up to how the code is structured. We can decide that later when we start using it. ########## gateway-util-common/src/main/java/org/apache/knox/gateway/util/ConcurrentSessionVerifier.java: ########## @@ -0,0 +1,79 @@ +/* + * 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.knox.gateway.util; + + +import java.util.HashSet; +import java.util.Map; +import java.util.Set; +import java.util.concurrent.ConcurrentHashMap; + +public class ConcurrentSessionVerifier { + private static Set<String> privilegedUsers = new HashSet<>(); + private static Set<String> nonPrivilegedUsers = new HashSet<>();; + private static int privilegedUserConcurrentSessionLimit = 3; + private static int nonPrivilegedUserConcurrentSessionLimit = 2; + private static Map<String, Integer> concurrentSessionCounter = new ConcurrentHashMap<>(); + private static final Object lock = new Object(); + + private ConcurrentSessionVerifier(){} + + public static synchronized void init(Set<String> privilegedUsers, Set<String> nonPrivilegedUsers, int privilegedUserConcurrentSessionLimit, int nonPrivilegedUserConcurrentSessionLimit){ + ConcurrentSessionVerifier.privilegedUsers = privilegedUsers; + ConcurrentSessionVerifier.nonPrivilegedUsers = nonPrivilegedUsers; + ConcurrentSessionVerifier.privilegedUserConcurrentSessionLimit = privilegedUserConcurrentSessionLimit; + ConcurrentSessionVerifier.nonPrivilegedUserConcurrentSessionLimit = nonPrivilegedUserConcurrentSessionLimit; + concurrentSessionCounter = new ConcurrentHashMap<>(); + } + + public static boolean verifySessionForUser(String username){ + if(!privilegedUsers.contains(username) && !nonPrivilegedUsers.contains(username)) { + return true; + } + synchronized(lock) { + if (!concurrentSessionCounter.containsKey(username)) { + concurrentSessionCounter.put(username, 0); + } + if ((privilegedUsers.contains(username) && !(concurrentSessionCounter.get(username) < privilegedUserConcurrentSessionLimit)) || (nonPrivilegedUsers.contains(username) && !(concurrentSessionCounter.get(username) < nonPrivilegedUserConcurrentSessionLimit))) { + return false; + } + incrementConcurrentSessionCount(username); + } + return true; + } + + private static synchronized void incrementConcurrentSessionCount(String username){ + int count = concurrentSessionCounter.get(username); Review Comment: Similarly, see if you can use `compute` to simplify this. For example: ```java concurrentSessionCounter.compute(username, (key ,value) -> value + 1); ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
