Update velocity version

Added a way to clear all locks on a server when it was empty when a user joins

.gitignore

@@ -118,5 +118,4 @@ run/
 !gradle-wrapper.jar
 
 # My stuff
-gradle/
+*.bat
-*.bat

Jenkinsfile

@@ -0,0 +1,23 @@
+pipeline {
+    agent any
+    environment {
+        NEXUS_CREDS = credentials('alttd-snapshot-user')
+    }
+    stages {
+        stage('Gradle') {
+            steps {
+                sh './gradlew shadowJar -x test -PalttdSnapshotUsername=$NEXUS_CREDS_USR -PalttdSnapshotPassword=$NEXUS_CREDS_PSW'
+            }
+        }
+        stage('Archive') {
+            steps {
+                archiveArtifacts artifacts: 'build/libs/', followSymlinks: false
+            }
+        }
+        stage('discord') {
+            steps {
+                discordSend description: "Build: ${BUILD_NUMBER}", showChangeset: true, result: currentBuild.currentResult, title: currentBuild.fullProjectName, webhookURL: env.discordwebhook
+            }
+        }
+    }
+}

build.gradle

@@ -1,3 +1,4 @@
+
 plugins {
     id 'java'
     id 'eclipse'
@@ -5,22 +6,32 @@ plugins {
 }
 
 group = 'com.alttd'
-version = '1.0-SNAPSHOT'
+version = '1.1-SNAPSHOT'
 
 repositories {
-    mavenCentral()
     maven {
-        name = 'velocitypowered-repo'
+        name = 'papermc'
-        url = 'https://nexus.velocitypowered.com/repository/maven-public/'
+        url = 'https://repo.papermc.io/repository/maven-public/'
     }
+    mavenCentral() // Add this to ensure access to JUnit libraries
 }
 
 dependencies {
-    compileOnly 'com.velocitypowered:velocity-api:3.1.0'
+    compileOnly 'com.velocitypowered:velocity-api:3.4.0-SNAPSHOT'
-    annotationProcessor 'com.velocitypowered:velocity-api:3.1.0'
+    annotationProcessor 'com.velocitypowered:velocity-api:3.4.0-SNAPSHOT'
+    implementation 'org.spongepowered:configurate-yaml:4.1.2'
+    implementation 'org.spongepowered:configurate-core:4.1.2'
+
+    // JUnit Jupiter dependencies
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.10.0'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.10.0'
+    testImplementation 'org.junit.jupiter:junit-jupiter-params:5.10.0'
+
+    // Enable JUnit tests
+    testImplementation 'org.junit.platform:junit-platform-launcher'
 }
 
-def targetJavaVersion = 17
+def targetJavaVersion = 21
 java {
     def javaVersion = JavaVersion.toVersion(targetJavaVersion)
     sourceCompatibility = javaVersion
@@ -36,6 +47,11 @@ tasks.withType(JavaCompile).configureEach {
     }
 }
 
+// Add this to run tests with JUnit Jupiter
+test {
+    useJUnitPlatform()
+}
+
 def templateSource = file('src/main/templates')
 def templateDest = layout.buildDirectory.dir('generated/sources/templates')
 def generateTemplates = tasks.register('generateTemplates', Copy) { task ->

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.6-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 #
-# Copyright © 2015-2021 the original authors.
+# Copyright © 2015-2021 the original authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -32,10 +32,10 @@
 #       Busybox and similar reduced shells will NOT work, because this script
 #       requires all of these POSIX shell features:
 #         * functions;
-#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
-#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
-#         * compound commands having a testable exit status, especially «case»;
+#         * compound commands having a testable exit status, especially «case»;
-#         * various built-in commands including «command», «set», and «ulimit».
+#         * various built-in commands including «command», «set», and «ulimit».
 #
 #   Important for patching:
 #
@@ -55,7 +55,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.
@@ -80,13 +80,11 @@ do
     esac
 done
 
-APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+# This is normally unused
-
+# shellcheck disable=SC2034
-APP_NAME="Gradle"
 APP_BASE_NAME=${0##*/}
-
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
-DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -133,22 +131,29 @@ location of your Java installation."
     fi
 else
     JAVACMD=java
-    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
 
 Please set the JAVA_HOME variable in your environment to match the
 location of your Java installation."
+    fi
 fi
 
 # Increase the maximum file descriptors if we can.
 if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
     case $MAX_FD in  #(
       '' | soft) :;; #(
       *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -193,11 +198,15 @@ if "$cygwin" || "$msys" ; then
     done
 fi
 
-# Collect all arguments for the java command;
+
-#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-#     shell script including quotes and variable substitutions, so put them in
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
-#     double quotes to make sure that they get re-expanded; and
+
-#   * put everything else in single quotes, so that it's not re-expanded.
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
@@ -205,6 +214,12 @@ set -- \
         org.gradle.wrapper.GradleWrapperMain \
         "$@"
 
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
 # Use "xargs" to parse quoted args.
 #
 # With -n1 it outputs one arg per line, with the quotes and backslashes removed.

gradlew.bat

@@ -14,7 +14,7 @@
 @rem limitations under the License.
 @rem
 
-@if "%DEBUG%" == "" @echo off
+@if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
 @rem
 @rem  Gradle startup script for Windows
@@ -25,7 +25,8 @@
 if "%OS%"=="Windows_NT" setlocal
 
 set DIRNAME=%~dp0
-if "%DIRNAME%" == "" set DIRNAME=.
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
 set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
@@ -40,13 +41,13 @@ if defined JAVA_HOME goto findJavaFromJavaHome
 
 set JAVA_EXE=java.exe
 %JAVA_EXE% -version >NUL 2>&1
-if "%ERRORLEVEL%" == "0" goto execute
+if %ERRORLEVEL% equ 0 goto execute
 
-echo.
+echo. 1>&2
-echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
-echo.
+echo. 1>&2
-echo Please set the JAVA_HOME variable in your environment to match the
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
-echo location of your Java installation.
+echo location of your Java installation. 1>&2
 
 goto fail
 
@@ -56,11 +57,11 @@ set JAVA_EXE=%JAVA_HOME%/bin/java.exe
 
 if exist "%JAVA_EXE%" goto execute
 
-echo.
+echo. 1>&2
-echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
-echo.
+echo. 1>&2
-echo Please set the JAVA_HOME variable in your environment to match the
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
-echo location of your Java installation.
+echo location of your Java installation. 1>&2
 
 goto fail
 
@@ -75,13 +76,15 @@ set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
 
 :end
 @rem End local scope for the variables with windows NT shell
-if "%ERRORLEVEL%"=="0" goto mainEnd
+if %ERRORLEVEL% equ 0 goto mainEnd
 
 :fail
 rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
 rem the _cmd.exe /c_ return code!
-if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+set EXIT_CODE=%ERRORLEVEL%
-exit /b 1
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
 
 :mainEnd
 if "%OS%"=="Windows_NT" endlocal

src/main/java/com/alttd/datalock/Config.java

@@ -1,12 +1,10 @@
 package com.alttd.datalock;
 
 import com.google.common.base.Throwables;
-import com.google.common.reflect.TypeToken;
+import org.spongepowered.configurate.ConfigurationNode;
-import ninja.leaping.configurate.ConfigurationNode;
+import org.spongepowered.configurate.ConfigurationOptions;
-import ninja.leaping.configurate.ConfigurationOptions;
+import org.spongepowered.configurate.serialize.SerializationException;
-import ninja.leaping.configurate.objectmapping.ObjectMappingException;
+import org.spongepowered.configurate.yaml.YamlConfigurationLoader;
-import ninja.leaping.configurate.yaml.YAMLConfigurationLoader;
-import org.yaml.snakeyaml.DumperOptions;
 
 import java.io.File;
 import java.io.IOException;
@@ -22,7 +20,7 @@ public final class Config {
     private static final String HEADER = "";
 
     public static ConfigurationNode config;
-    public static YAMLConfigurationLoader configLoader;
+    public static YamlConfigurationLoader configLoader;
 
     static int version;
     static boolean verbose;
@@ -30,12 +28,11 @@ public final class Config {
     public static File CONFIG_PATH;
 
     public static void init() { // todo setup share for the config
-        CONFIG_PATH = new File(DataLock.getDataDirectory().toAbsolutePath() + File.separator + "DataLock");
+        CONFIG_PATH = new File(DataLock.getDataDirectory().toAbsolutePath().toString());
         File configFile = new File(CONFIG_PATH, "config.yml");
 
-        configLoader = YAMLConfigurationLoader.builder()
+        configLoader = YamlConfigurationLoader.builder()
-                .setFile(configFile)
+                .file(configFile)
-                .setFlowStyle(DumperOptions.FlowStyle.BLOCK)
                 .build();
         if (!configFile.getParentFile().exists()) {
             if (!configFile.getParentFile().mkdirs()) {
@@ -53,7 +50,7 @@ public final class Config {
         }
 
         try {
-            config = configLoader.load(ConfigurationOptions.defaults().setHeader(HEADER));
+            config = configLoader.load(ConfigurationOptions.defaults().header(HEADER));
         } catch (IOException e) {
             e.printStackTrace();
         }
@@ -76,24 +73,24 @@ public final class Config {
                     try {
                         method.setAccessible(true);
                         method.invoke(instance);
-                    } catch (InvocationTargetException | IllegalAccessException ex) {
+                    } catch (InvocationTargetException | IllegalAccessException e) {
-                        throw Throwables.propagate(ex.getCause());
+                        throw Throwables.propagate(e.getCause());
                     }
                 }
             }
         }
         try {
             configLoader.save(config);
-        } catch (IOException ex) {
+        } catch (IOException e) {
-            throw Throwables.propagate(ex.getCause());
+            throw Throwables.propagate(e.getCause());
         }
     }
 
     public static void saveConfig() {
         try {
             configLoader.save(config);
-        } catch (IOException ex) {
+        } catch (IOException e) {
-            throw Throwables.propagate(ex.getCause());
+            throw Throwables.propagate(e.getCause());
         }
     }
 
@@ -102,48 +99,54 @@ public final class Config {
     }
 
     private static void set(String path, Object def) {
-        if (config.getNode(splitPath(path)).isVirtual())
+        if (config.node(splitPath(path)).virtual()) {
-            config.getNode(splitPath(path)).setValue(def);
+            try {
+                config.node(splitPath(path)).set(def);
+            } catch (SerializationException e) {
+                e.printStackTrace();
+            }
+        }
     }
 
     private static void setString(String path, String def) {
         try {
-            if (config.getNode(splitPath(path)).isVirtual())
+            if (config.node(splitPath(path)).virtual())
-                config.getNode(splitPath(path)).setValue(TypeToken.of(String.class), def);
+                config.node(splitPath(path)).set(String.class, def);
-        } catch (ObjectMappingException ex) {
+        } catch (SerializationException e) {
         }
     }
 
     private static boolean getBoolean(String path, boolean def) {
         set(path, def);
-        return config.getNode(splitPath(path)).getBoolean(def);
+        return config.node(splitPath(path)).getBoolean(def);
     }
 
     private static double getDouble(String path, double def) {
         set(path, def);
-        return config.getNode(splitPath(path)).getDouble(def);
+        return config.node(splitPath(path)).getDouble(def);
     }
 
     private static int getInt(String path, int def) {
         set(path, def);
-        return config.getNode(splitPath(path)).getInt(def);
+        return config.node(splitPath(path)).getInt(def);
     }
 
     private static String getString(String path, String def) {
         setString(path, def);
-        return config.getNode(splitPath(path)).getString(def);
+        return config.node(splitPath(path)).getString(def);
     }
 
     private static Long getLong(String path, Long def) {
         set(path, def);
-        return config.getNode(splitPath(path)).getLong(def);
+        return config.node(splitPath(path)).getLong(def);
     }
 
     private static <T> List<String> getList(String path, T def) {
         try {
             set(path, def);
-            return config.getNode(splitPath(path)).getList(TypeToken.of(String.class));
+            return config.node(splitPath(path)).getList(String.class);
-        } catch (ObjectMappingException ex) {
+        } catch (SerializationException e) {
+            e.printStackTrace();
         }
         return new ArrayList<>();
     }
@@ -152,8 +155,12 @@ public final class Config {
      * ONLY EDIT ANYTHING BELOW THIS LINE
      **/
     public static List<String> PLUGIN_MESSAGE_CHANNELS = new ArrayList<>(List.of("example_plugin:table_1"));
+    public static boolean DEBUG = false;
 
-    private static void loadGroups() {
+    private static void loadSettings() {
         PLUGIN_MESSAGE_CHANNELS = getList("settings.channels", new ArrayList<>(List.of("example_plugin:table_1")));
+        DEBUG = getBoolean("settings.debug", DEBUG);
+        if (DEBUG)
+            Logger.info("DEBUG: on");
     }
 }

src/main/java/com/alttd/datalock/DataLock.java

@@ -37,6 +37,7 @@ public class DataLock {
     public void onProxyInitialization(ProxyInitializeEvent event) {
         reloadConfig();
         server.getEventManager().register(this, EventListener.getInstance());
+        server.getEventManager().register(this, new PlayerListener());
         new Reload(server);
     }
 

src/main/java/com/alttd/datalock/EventListener.java

@@ -8,27 +8,43 @@ import com.velocitypowered.api.event.connection.PluginMessageEvent;
 import com.velocitypowered.api.proxy.Player;
 import com.velocitypowered.api.proxy.ServerConnection;
 import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
+import com.velocitypowered.api.proxy.messages.ChannelRegistrar;
 import com.velocitypowered.api.proxy.messages.MinecraftChannelIdentifier;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
 
 import java.util.*;
+import java.util.stream.Collectors;
 
 public class EventListener {
 
+    private EventListener() {}
+
+    //    private final Idempotency idempotencyStorage = new Idempotency();
     private final HashMap<ChannelIdentifier, HashSet<Lock>> queuedLocks = new HashMap<>();
     private final HashMap<ChannelIdentifier, HashSet<Lock>> channelLockMap = new HashMap<>();
-    private final static List<ChannelIdentifier> channelIdentifierList = new ArrayList<>();
+
+    private synchronized void putDataInChannelLockMap(ChannelIdentifier identifier, HashSet<Lock> set) {
+        channelLockMap.put(identifier, set);
+    }
+
+    private synchronized HashSet<Lock> getSetFromChannelLockMap(ChannelIdentifier identifier) {
+        return channelLockMap.getOrDefault(identifier, new HashSet<>());
+    }
+    private final List<ChannelIdentifier> channelIdentifierList = new ArrayList<>();
+
     private static EventListener instance = null;
 
     public static EventListener getInstance() {
+        if (instance == null)
+            return new EventListener();
         return instance;
     }
 
     public static void reload()
     {
-        if (instance == null)
+        instance = getInstance();
-            instance = new EventListener();
+        instance.channelIdentifierList.clear();
-        EventListener.channelIdentifierList.clear();
+        ChannelRegistrar channelRegistrar = DataLock.getServer().getChannelRegistrar();
         for (String s : Config.PLUGIN_MESSAGE_CHANNELS) {
             String[] split = s.split(":");
             if (split.length != 2) {
@@ -36,20 +52,64 @@ public class EventListener {
                 continue;
             }
             MinecraftChannelIdentifier minecraftChannelIdentifier = MinecraftChannelIdentifier.create(split[0], split[1]);
-            if (EventListener.channelIdentifierList.contains(minecraftChannelIdentifier)) {
+            if (instance.channelIdentifierList.contains(minecraftChannelIdentifier)) {
                 Logger.warn("Duplicate message channel [%] in config.", s);
                 continue;
             }
-            EventListener.channelIdentifierList.add(minecraftChannelIdentifier);
+            if (Config.DEBUG)
+                Logger.info("Loaded entry [%] as [%].", s, minecraftChannelIdentifier.asKey().asString());
+            instance.channelIdentifierList.add(minecraftChannelIdentifier);
+            channelRegistrar.register(minecraftChannelIdentifier);
         }
     }
 
+    public synchronized void clearServer(int hashCode) {
+        channelLockMap.keySet().forEach(key -> {
+            HashSet<Lock> temp = new HashSet<>();
+            HashSet<Lock> locks = channelLockMap.get(key);
+            for (Lock lock : locks) {
+                if (lock.getServerHash() == hashCode)
+                    temp.add(lock);
+            }
+            for (Lock lock : temp) {
+                locks.remove(lock);
+                queueNextLock(locks, lock, key, null);
+                if (Config.DEBUG)
+                    Logger.info("Clearing % from % due to clear server being called for the server that lock is on", lock.getData(), key.getId());
+            }
+            putDataInChannelLockMap(key, locks);
+        });
+    }
+
+    private synchronized String formatLockMap(HashMap<ChannelIdentifier, HashSet<Lock>> map) {
+        StringBuilder stringBuilder = new StringBuilder();
+        for (ChannelIdentifier plugin : map.keySet()) {
+            stringBuilder
+                    .append(plugin)
+                    .append(": ")
+                    .append(map.get(plugin).size())
+                    .append(" entries\n")
+                    .append(
+                            map.get(plugin)
+                                    .stream()
+                                    .map(lock -> lock.getData() + " : " + lock.getServerHash())
+                                    .collect(Collectors.joining(", ")))
+                    .append("\n---\n");
+        }
+        return stringBuilder.toString();
+    }
+
     @Subscribe
     public void onPluginMessageEvent(PluginMessageEvent event) {
         ChannelIdentifier identifier = event.getIdentifier();
-        if (!EventListener.channelIdentifierList.contains(identifier))
+        if (Config.DEBUG)
+            Logger.info("Received message on [%].", identifier.getId());
+        if (!channelIdentifierList.contains(identifier))
             return;
 
+        if (Config.DEBUG)
+            Logger.info("Current locks:\n%\nQueued locks:\n%", formatLockMap(channelLockMap), formatLockMap(queuedLocks));
+
         event.setResult(PluginMessageEvent.ForwardResult.handled());
 
         if(event.getSource() instanceof Player) {
@@ -62,7 +122,7 @@ public class EventListener {
             return;
         }
 
-        HashSet<Lock> hashLock = channelLockMap.getOrDefault(identifier, new HashSet<>());
+        HashSet<Lock> hashLock = getSetFromChannelLockMap(identifier);
         ByteArrayDataInput in = ByteStreams.newDataInput(event.getData());
         String channel;
         try {
@@ -81,23 +141,72 @@ public class EventListener {
             return;
         }
 
-        switch (channel.toLowerCase()) {
+        if (!isValid(channel.toLowerCase(), data))
-            case "try-lock" -> tryLock(identifier, hashLock, data, serverConnection);
+            return;
-            case "check-lock" -> checkLock(identifier, hashLock, data, serverConnection);
+
-            case "try-unlock" -> tryUnlock(identifier, hashLock, data, serverConnection);
+        UUID idempotency;
+        try {
+            idempotency = UUID.fromString(in.readUTF());
+        } catch (Exception e) {
+            Logger.error("No idempotency key found.",
+                    identifier.getId());
+            idempotency = null; //TODO change this to return
+        }
+
+
+        if (Config.DEBUG)
+            Logger.info("Plugin message channel: [%]", channel.toLowerCase());
+
+        Optional<RequestType> first = Arrays.stream(RequestType.values()).filter(value -> value.subChannel.equalsIgnoreCase(channel)).findFirst();
+        if (first.isEmpty()) {
+            Logger.warn("Received invalid request type [%]", channel.toLowerCase());
+            return;
+        }
+//        RequestType requestType = first.get();
+//        if (!idempotencyStorage.putIdempotencyData(requestType, new IdempotencyData(requestType, data, idempotency)))
+//            return;
+//        switch (requestType) {
+//
+//        }
+        switch (channel.toLowerCase()) { //TODO something with idempotency for function
+            case "try-lock" -> tryLock(identifier, hashLock, data, idempotency, serverConnection);
+            case "check-lock" -> checkLock(identifier, hashLock, data, idempotency, serverConnection);
+            case "try-unlock" -> tryUnlock(identifier, hashLock, data, idempotency, serverConnection);
         }
     }
 
-    private void tryLock(ChannelIdentifier identifier, HashSet<Lock> lockSet, String data, ServerConnection serverConnection) {
+    private final HashMap<String, Long> validMap = new HashMap<>();
+    private synchronized boolean isValid(String channel, String data) {
+        String key = channel + data;
+        long currentTime = new Date().getTime();
+        if (validMap.containsKey(key)) {
+            Long time = validMap.get(key);
+            if (time < (currentTime - 1000)) {
+                validMap.remove(key);
+                return true;
+            }
+            return false;
+        } else {
+            validMap.put(key, currentTime);
+            return true;
+        }
+    }
+
+    private void sendPluginMessage(String channel, boolean result, String data, UUID idempotency, ServerConnection serverConnection, ChannelIdentifier identifier) {
         ByteArrayDataOutput out = ByteStreams.newDataOutput();
-        out.writeUTF("try-lock-result");
+        out.writeUTF(channel);
+        out.writeBoolean(result);
+        out.writeUTF(data);
+        out.writeUTF(idempotency.toString());
+        serverConnection.sendPluginMessage(identifier, out.toByteArray());
+    }
+    private void tryLock(ChannelIdentifier identifier, HashSet<Lock> lockSet, String data, UUID idempotency, ServerConnection serverConnection) {
+        String channel = "try-lock-result";
 
         Lock lock = new Lock(serverConnection.getServerInfo().hashCode(), data);
         if (lockSet.contains(lock)) {
             //An entry from this server already exists, so we can say that it's locked
-            out.writeBoolean(true);
+            sendPluginMessage(channel, true, lock.getData(), idempotency, serverConnection, identifier);
-            out.writeUTF(lock.getData());
-            serverConnection.sendPluginMessage(identifier, out.toByteArray());
             return;
         }
 
@@ -113,72 +222,73 @@ public class EventListener {
             }
             else {
                 //An entry from another server exists, so we can't lock it
-                out.writeBoolean(false);
+                sendPluginMessage(channel, false, lock.getData(), idempotency, serverConnection, identifier);
-                out.writeUTF(lock.getData());
+                queueLock(queuedLocks.getOrDefault(identifier, new HashSet<>()), identifier, lock, serverConnection, idempotency);
-                serverConnection.sendPluginMessage(identifier, out.toByteArray());
-                queueLock(queuedLocks.getOrDefault(identifier, new HashSet<>()), identifier, lock, serverConnection);
                 return;
             }
         }
 
         //Lock the data
         lockSet.add(lock);
-        channelLockMap.put(identifier, lockSet);
+        putDataInChannelLockMap(identifier, lockSet);
-
+        sendPluginMessage(channel, true, lock.getData(), idempotency, serverConnection, identifier);
-        out.writeBoolean(true);
-        out.writeUTF(lock.getData());
-        serverConnection.sendPluginMessage(identifier, out.toByteArray());
     }
 
-    private void checkLock(ChannelIdentifier identifier, HashSet<Lock> lockSet, String data, ServerConnection serverConnection) {
+    private void checkLock(ChannelIdentifier identifier, HashSet<Lock> lockSet, String data, UUID idempotency, ServerConnection serverConnection) {
-        ByteArrayDataOutput out = ByteStreams.newDataOutput();
         Lock lock = new Lock(serverConnection.hashCode(), data);
+        String channel = "check-lock-result";
+        boolean result;
 
-        out.writeUTF("check-lock-result");
         if (lockSet.contains(lock)) //We locked this, but we still return true since it's locked
-            out.writeBoolean(true);
+            result = true;
         else if (lockSet.stream().anyMatch(a -> a.compareTo(lock) == 0))
-            out.writeBoolean(true); //There is a lock (not ours, but it's still locked)
+            result = true; //There is a lock (not ours, but it's still locked)
         else
-            out.writeBoolean(false); //The data is not locked
+            result = false; //The data is not locked
 
-        out.writeUTF(lock.getData());
+        sendPluginMessage(channel, result, lock.getData(), idempotency, serverConnection, identifier);
-        serverConnection.sendPluginMessage(identifier, out.toByteArray());
     }
 
-    private void tryUnlock(ChannelIdentifier identifier, HashSet<Lock> lockSet, String data, ServerConnection serverConnection) {
+    private void tryUnlock(ChannelIdentifier identifier, HashSet<Lock> lockSet, String data, UUID idempotency, ServerConnection serverConnection) {
-        ByteArrayDataOutput out = ByteStreams.newDataOutput();
+        int hash = serverConnection.getServerInfo().hashCode();
-        out.writeUTF("try-unlock-result");
+        String channel = "try-unlock-result";
 
-        Lock lock = new Lock(serverConnection.getServerInfo().hashCode(), data);
+        Lock lock = new Lock(hash, data);
         if (lockSet.contains(lock)) //Lock is in the list, but it's made by this server, so we can unlock it
         {
-            out.writeBoolean(true);
-            out.writeUTF(lock.getData());
             lockSet.remove(lock);
-            channelLockMap.put(identifier, lockSet);
+            queueNextLock(lockSet, lock, identifier, idempotency);
-            serverConnection.sendPluginMessage(identifier, out.toByteArray());
+            putDataInChannelLockMap(identifier, lockSet);
-            queueNextLock(lockSet, lock, identifier);
+            sendPluginMessage(channel, true, lock.getData(), idempotency, serverConnection, identifier);
             return;
         }
 
         Optional<Lock> first = lockSet.stream().filter(a -> a.compareTo(lock) == 0).findFirst();
         if (first.isEmpty()) //There is no entry with this data, so we can say it's unlocked
         {
-            out.writeBoolean(true);
+            removeQueuedLock(queuedLocks.get(identifier), lock, hash);
-            out.writeUTF(lock.getData());
+            sendPluginMessage(channel, true, lock.getData(), idempotency, serverConnection, identifier);
-            serverConnection.sendPluginMessage(identifier, out.toByteArray());
+            queueNextLock(lockSet, lock, identifier, idempotency);
-            queueNextLock(lockSet, lock, identifier);
             return;
         }
 
         //There is an entry with this data, but it's not owned by this server, so we can't unlock it
-        out.writeBoolean(false);
+        sendPluginMessage(channel, false, lock.getData(), idempotency, serverConnection, identifier);
-        out.writeUTF(lock.getData());
-        serverConnection.sendPluginMessage(identifier, out.toByteArray());
     }
 
-    private void queueLock(HashSet<Lock> lockSet, ChannelIdentifier identifier, Lock lock, ServerConnection serverConnection) {
+    private void removeQueuedLock(HashSet<Lock> locks, Lock exampleLock, int hash) {
+        if (locks == null)
+            return;
+        Optional<Lock> other = locks.stream().filter(a -> a.compareTo(exampleLock) == 0).findFirst();
+        if (other.isEmpty())
+            return;
+        Lock lock = other.get();
+        if (lock.getServerHash() == hash)
+            locks.remove(lock);
+    }
+
+    private void queueLock(HashSet<Lock> lockSet, ChannelIdentifier identifier, Lock lock, ServerConnection serverConnection, UUID idempotency) {
+        String channel = "queue-lock-failed";
         if (lockSet.contains(lock)) {
             //Lock already queued we don't have to queue it again
             return;
@@ -191,12 +301,8 @@ public class EventListener {
                     .findAny();
             if (optionalRegisteredServer.isPresent()) {
                 //The server that queued this lock is still active, so we can't queue a new one
-                RegisteredServer registeredServer = optionalRegisteredServer.get();
+//                RegisteredServer registeredServer = optionalRegisteredServer.get(); todo this was once used in the plugin message, check if it was needed
-                ByteArrayDataOutput out = ByteStreams.newDataOutput();
+                sendPluginMessage(channel, false, queuedLock.getData(), idempotency, serverConnection, identifier);
-                out.writeUTF("queue-lock-failed");
-                out.writeUTF(queuedLock.getData());
-                out.writeUTF(registeredServer.getServerInfo().getName());
-                serverConnection.sendPluginMessage(identifier, out.toByteArray());
                 return;
             }
             Logger.warn("Removing queued lock [%] due to being unable to find a server where that lock could be active", queuedLock.getData());
@@ -206,29 +312,29 @@ public class EventListener {
         queuedLocks.put(identifier, lockSet);
     }
 
-    private void queueNextLock(HashSet<Lock> lockSet, Lock lock, ChannelIdentifier identifier) {
+    private void queueNextLock(HashSet<Lock> lockSet, Lock lock, ChannelIdentifier identifier, UUID idempotency) {
+        String channel = "locked-queued-lock";
         if (!queuedLocks.containsKey(identifier))
             return;
         HashSet<Lock> queuedLockSet = queuedLocks.get(identifier);
-        Optional<Lock> optionalQueuedLock = queuedLockSet.stream().filter(l -> l.compareTo(lock) == 0).findFirst();
+        Optional<Lock> optionalQueuedLock = queuedLockSet.stream().filter(l -> l.getData().equals(lock.getData())).findFirst();
         if (optionalQueuedLock.isEmpty())
             return;
         Lock queuedLock = optionalQueuedLock.get();
-        queuedLockSet.remove(lock);
+        queuedLockSet.remove(queuedLock);
+        queuedLocks.put(identifier, queuedLockSet);
 
         Optional<RegisteredServer> optionalRegisteredServer = DataLock.getServer().getAllServers().stream()
                 .filter(registeredServer -> registeredServer.getServerInfo().hashCode() == queuedLock.getServerHash())
                 .findAny();
         if (optionalRegisteredServer.isEmpty()) {
             Logger.warn("Removing queued lock [%] due to being unable to find a server where that lock could be active", queuedLock.getData());
+            queueNextLock(lockSet, lock, identifier, idempotency);
             return;
         }
         RegisteredServer registeredServer = optionalRegisteredServer.get();
         lockSet.add(queuedLock);
-        ByteArrayDataOutput out = ByteStreams.newDataOutput();
+        sendPluginMessage(channel, true, queuedLock.getData(), idempotency, (ServerConnection) registeredServer, identifier); //TODO test if this cast works
-        out.writeUTF("locked-queued-lock");
-        out.writeUTF(queuedLock.getData());
-        registeredServer.sendPluginMessage(identifier, out.toByteArray());
     }
 
 }

src/main/java/com/alttd/datalock/Idempotency.java

@@ -0,0 +1,51 @@
+package com.alttd.datalock;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Set;
+
+class Idempotency {
+
+    private final HashMap<RequestType, HashSet<IdempotencyData>> idempotencyMap;
+
+    protected Idempotency() {
+        idempotencyMap = new HashMap<>();
+    }
+
+    private HashSet<IdempotencyData> getIdempotencySet(RequestType requestType) {
+        return idempotencyMap.getOrDefault(requestType, new HashSet<>());
+    }
+
+    private void putIdempotencySet(RequestType requestType, HashSet<IdempotencyData> idempotencySet) {
+        idempotencyMap.put(requestType, idempotencySet);
+    }
+
+    /**
+     * Add IdempotencyData to the list of active queries
+     * @param idempotencyData Data to add to the set
+     * @return true if entry did not exist yet
+     */
+    protected synchronized boolean putIdempotencyData(RequestType requestType, IdempotencyData idempotencyData) {
+        HashSet<IdempotencyData> idempotencySet = getIdempotencySet(requestType);
+        boolean result = idempotencySet.add(idempotencyData);
+        putIdempotencySet(requestType, idempotencySet);
+        return result;
+    }
+
+    /**
+     * Remove IdempotencyData from the list of active queries
+     * @param idempotencyData Data to remove from the set
+     * @return True if the data that was requested to be removed was in the set and was removed
+     */
+    protected synchronized boolean removeIdempotencyData(RequestType requestType, IdempotencyData idempotencyData) {
+        HashSet<IdempotencyData> idempotencySet = getIdempotencySet(requestType);
+        boolean result = idempotencySet.remove(idempotencyData);
+        putIdempotencySet(requestType, idempotencySet);
+        return result;
+    }
+
+    protected synchronized Set<IdempotencyData> getIdempotencyData(RequestType requestType) {
+        return Collections.unmodifiableSet(getIdempotencySet(requestType));
+    }
+}

src/main/java/com/alttd/datalock/IdempotencyData.java

@@ -0,0 +1,10 @@
+package com.alttd.datalock;
+
+import java.util.UUID;
+
+record IdempotencyData(RequestType channel, String data, UUID idempotencyToken) {
+    @Override
+    public String toString() {
+        return "Channel: [" + channel + "] Data: [" + data + "] Idempotency Token: [" + idempotencyToken + "]";
+    }
+}

src/main/java/com/alttd/datalock/Lock.java

@@ -25,13 +25,13 @@ public class Lock implements Comparable {
 
     @Override
     public final boolean equals(@Nullable Object o) {
-        if (this == o) {
+        Lock other = (Lock) o;
+        if (this == other) {
             return true;
         }
-        if (o == null || getClass() != o.getClass()) {
+        if (other == null || getClass() != other.getClass()) {
             return false;
         }
-        Lock other = (Lock) o;
         return data.equals(other.data) && serverHash == other.serverHash;
     }
 
@@ -43,6 +43,10 @@ public class Lock implements Comparable {
 
     @Override
     public int compareTo(@NotNull Object o) {
-        return ((Lock) o).data.compareTo(data);
+        Lock lock = (Lock) o;
+        int data = lock.data.compareTo(this.data);
+        if (data != 0)
+            return data;
+        return Integer.compare(lock.getServerHash(), getServerHash());
     }
 }

src/main/java/com/alttd/datalock/PlayerListener.java

@@ -0,0 +1,30 @@
+package com.alttd.datalock;
+
+import com.velocitypowered.api.event.Subscribe;
+import com.velocitypowered.api.event.player.ServerConnectedEvent;
+import com.velocitypowered.api.proxy.Player;
+import com.velocitypowered.api.proxy.server.RegisteredServer;
+import com.velocitypowered.api.proxy.server.ServerInfo;
+
+import java.util.Collection;
+import java.util.Optional;
+
+public class PlayerListener {
+
+    @Subscribe
+    void onPlayerConnect(ServerConnectedEvent event) {
+        Player player = event.getPlayer();
+        ServerInfo serverInfo = event.getServer().getServerInfo();
+        Collection<Player> playersConnected = event.getServer().getPlayersConnected();
+        if (playersConnected.isEmpty() || playersConnected.size() == 1 && playersConnected.contains(player))
+            EventListener.getInstance().clearServer(serverInfo.hashCode());
+
+        Optional<RegisteredServer> previousServer = event.getPreviousServer();
+        if (previousServer.isEmpty())
+            return;
+        serverInfo = previousServer.get().getServerInfo();
+        if (playersConnected.isEmpty() || playersConnected.size() == 1 && playersConnected.contains(player))
+            EventListener.getInstance().clearServer(serverInfo.hashCode());
+    }
+
+}

src/main/java/com/alttd/datalock/RequestType.java

@@ -0,0 +1,13 @@
+package com.alttd.datalock;
+
+enum RequestType {
+    TRY_LOCK("try-lock"),
+    TRY_UNLOCK("try-unlock"),
+    CHECK_LOCK("check-lock");
+
+    String subChannel;
+
+    RequestType(String subChannel) {
+        this.subChannel = subChannel;
+    }
+}

src/test/java/com/alttd/datalock/LockTest.java

@@ -0,0 +1,27 @@
+package com.alttd.datalock;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class LockTest {
+
+    @org.junit.jupiter.api.Test
+    void testEquals() {
+        assertTrue(new Lock(123, "test").equals(new Lock(123, "test")));
+        assertFalse(new Lock(123, "test1").equals(new Lock(123, "test2")));
+        assertFalse(new Lock(123, "test").equals(new Lock(-123, "test")));
+    }
+
+    @org.junit.jupiter.api.Test
+    void testHashCode() {
+        assertEquals(new Lock(123, "test").hashCode(), new Lock(123, "test").hashCode());
+        assertNotEquals(new Lock(123, "test1").hashCode(), new Lock(123, "test2").hashCode());
+        assertNotEquals(new Lock(123, "test").hashCode(), new Lock(-123, "test").hashCode());
+    }
+
+    @org.junit.jupiter.api.Test
+    void compareTo() {
+        assertEquals(0, new Lock(123, "test").compareTo(new Lock(123, "test")));
+        assertNotEquals(0, new Lock(123, "test1").compareTo(new Lock(123, "test")));
+        assertNotEquals(0, new Lock(123, "test").compareTo(new Lock(-123, "test")));
+    }
+}