feat: implement cooldowns (#1)

README.md

@@ -7,4 +7,5 @@ Command pre- & post-processors for [Cloud v2](https://github.com/incendo/cloud).
 
 ## postprocessors
 
-- [cloud-processors-confirmation](./cloud-processors-confirmation)
+- [cloud-processors-confirmation](./cloud-processors-confirmation)
+- [cloud-processors-cooldown](./cloud-processors-cooldown)

cloud-processors-common/src/main/java/org/incendo/cloud/processors/immutables/StagedImmutableBuilder.java

@@ -46,7 +46,9 @@
         defaultAsDefault = true,
         put = "*",
         putAll = "*",
-        stagedBuilder = true
+        stagedBuilder = true,
+        depluralize = true,
+        depluralizeDictionary = "creationListeners:creationListener"
 )
 @Target({ElementType.TYPE, ElementType.METHOD, ElementType.PACKAGE})
 @Retention(RetentionPolicy.SOURCE)

cloud-processors-cooldown/README.md

@@ -0,0 +1,90 @@
+# cloud-processors-cooldown
+
+Postprocessor that adds command cooldowns.
+
+## Installation
+
+cloud-processors-cooldown is not yet available on Maven Central.
+
+## Usage
+
+The cooldown system is managed by a `CooldownManager`, so the first step is to create an instance of that:
+```java
+CooldownManager<YourSenderType> cooldownManager = CooldownManager.of(configuration);
+```
+The configuration is an instance of `CooldownConfiguration`. Refer to the JavaDocs for information about specific options,
+but an example would be:
+```java
+CooldownConfiguration configuration = CooldownConfiguration.<YourSenderType>builder()
+        .repository(CooldownRepository.forMap(new HashMap<>()))
+        .addActiveCooldownListener(...)
+        .addCooldownCreationListener(...)
+        .cooldownNotifier(notifier)
+        .build();
+```
+The listeners are invoked when different events take place. The active cooldown listener in particular may be used to
+inform the command sender that their command execution got blocked due to an active cooldown.
+
+The repository stores active cooldowns for a command sender in the form of cooldown profiles.
+The cooldowns are grouped by their `CooldownGroup`, by default a unique group will be created per command.
+You may create a named group by using `CooldownGroup.named(name)`. Commands that use the same cooldown group
+will have their cooldowns shared by the command sender.
+
+You may create a repository from a map, `CloudCache` or even implement your own. If you want to persist the cooldowns
+across multiple temporary sessions then you may use a mapping repository to store the cooldown profiles for a persistent key,
+rather than the potentially temporary command sender objects:
+```java
+CooldownRepository repository = CooldownRepository.mapping(
+        sender -> sender.uuid(),
+        CooldownRepository.forMap(new HashMap<UUID, CooldownProfile>())
+);
+```
+
+You may also customize how the cooldown profiles are created by passing a `CooldownProfileFactory` to the `CooldownConfiguration`.
+
+If you want to have the cooldowns automatically removed from the repository to prevent unused profiles from taking up memory you
+may register a `ScheduledCleanupCreationListener`:
+```java
+CooldownRepository repository = CooldownRepository.forMap(new HashMap<>());
+ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
+CooldownConfiguration configuration = CooldownConfiguration.<YourSenderType>builder()
+        // ...
+        .repository(repository)
+        .addCreationListener(new ScheduledCleanupCreationListener(executorService, repository))
+        .build();
+```
+
+You then need to register the postprocessor:
+```java
+commandManager.registerCommandPostProcessor(cooldownManager.createPostprocessor());
+```
+
+### Builders
+
+The cooldowns are configured using a `Cooldown` instance:
+```java
+Cooldown cooldown = Cooldown.of(DurationFunction.constant(Duration.ofMinutes(5L)));
+Cooldown cooldown = Cooldown.of(DurationFunction.constant(Duration.ofMinutes(5L)), CooldownGroup.named("group-name"));
+```
+which can then be applied to the command by either manually setting the meta value:
+```java
+commandBuilder.meta(CooldownManager.META_COOLDOWN_DURATION, cooldown);
+```
+or by applying the cooldown to the builder:
+```java
+commandBuilder.apply(cooldown);
+```
+
+### Annotations
+
+Annotated commands may use the `@Cooldown` annotation:
+```java
+@Cooldown(duration = 5, timeUnit = ChronoUnit.MINUTES, group = "some-group")
+public void yourCommand() {
+    // ...
+}
+```
+You need to install the builder modifier for this to work:
+```java
+CooldownBuilderModifier.install(annotationParser);
+```

cloud-processors-cooldown/build.gradle.kts

@@ -0,0 +1,16 @@
+plugins {
+    id("cloud-processors.base-conventions")
+    id("cloud-processors.publishing-conventions")
+}
+
+dependencies {
+    api(projects.cloudProcessorsCommon)
+
+    compileOnly(libs.cloud.annotations)
+}
+
+// TODO(City): Disable this
+// we're getting errors on generated files due to -Werror :(
+tasks.withType<JavaCompile> {
+    options.compilerArgs.remove("-Werror")
+}

cloud-processors-cooldown/src/main/java/org/incendo/cloud/processors/cooldown/Cooldown.java

@@ -0,0 +1,102 @@
+//
+// MIT License
+//
+// Copyright (c) 2024 Incendo
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+package org.incendo.cloud.processors.cooldown;
+
+import cloud.commandframework.Command;
+import org.apiguardian.api.API;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.immutables.value.Value;
+import org.incendo.cloud.processors.immutables.StagedImmutableBuilder;
+
+/**
+ * An instance of a cooldown for a {@link CooldownGroup} belonging to a command sender.
+ *
+ * @param <C> command sender type
+ * @since 1.0.0
+ */
+@StagedImmutableBuilder
+@Value.Immutable
+@API(status = API.Status.STABLE, since = "1.0.0")
+public interface Cooldown<C> extends Command.Builder.Applicable<C> {
+
+    /**
+     * Returns a new cooldown with the given {@code duration}
+     * using {@link CooldownConfiguration#fallbackGroup()} as the group.
+     *
+     * @param <C>      command sender type
+     * @param duration the duration
+     * @return the cooldown
+     */
+    static <C> @NonNull Cooldown<C> of(final @NonNull DurationFunction<C> duration) {
+        return Cooldown.<C>builder().duration(duration).build();
+    }
+
+    /**
+     * Returns a new cooldown with the given {@code duration} and {@code group}.
+     *
+     * @param <C>      command sender type
+     * @param duration the duration
+     * @param group    cooldown group
+     * @return the cooldown
+     */
+    static <C> @NonNull Cooldown<C> of(
+            final @NonNull DurationFunction<C> duration,
+            final @NonNull CooldownGroup group
+    ) {
+        return Cooldown.<C>builder().duration(duration).group(group).build();
+    }
+
+    /**
+     * Returns a new cooldown builder.
+     *
+     * @param <C> command sender type
+     * @return the builder
+     */
+    static <C> ImmutableCooldown.@NonNull DurationBuildStage<C> builder() {
+        return ImmutableCooldown.builder();
+    }
+
+    /**
+     * Returns the cooldown duration.
+     *
+     * @return the duration
+     */
+    @NonNull DurationFunction<C> duration();
+
+    /**
+     * Returns the group that this instance belongs to.
+     * If set to {@code null} then {@link CooldownConfiguration#fallbackGroup()} will be used.
+     *
+     * @return the cooldown group
+     */
+    default @Nullable CooldownGroup group() {
+        return null;
+    }
+
+    @Override
+    default Command.@NonNull Builder<C> applyToCommandBuilder(Command.@NonNull Builder<C> builder) {
+        return builder.meta(CooldownManager.META_COOLDOWN_DURATION, this);
+    }
+}

cloud-processors-cooldown/src/main/java/org/incendo/cloud/processors/cooldown/CooldownConfiguration.java

@@ -0,0 +1,126 @@
+//
+// MIT License
+//
+// Copyright (c) 2024 Incendo
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+package org.incendo.cloud.processors.cooldown;
+
+import cloud.commandframework.Command;
+import cloud.commandframework.context.CommandContext;
+import java.time.Clock;
+import java.util.List;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import org.apiguardian.api.API;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.immutables.value.Value;
+import org.incendo.cloud.processors.cooldown.listener.CooldownActiveListener;
+import org.incendo.cloud.processors.cooldown.listener.CooldownCreationListener;
+import org.incendo.cloud.processors.cooldown.profile.CooldownProfileFactory;
+import org.incendo.cloud.processors.cooldown.profile.StandardCooldownProfileFactory;
+import org.incendo.cloud.processors.immutables.StagedImmutableBuilder;
+
+/**
+ * Configuration for a {@link CooldownManager}.
+ *
+ * @param <C> command sender type
+ * @since 1.0.0
+ */
+@Value.Immutable
+@StagedImmutableBuilder
+@API(status = API.Status.STABLE, since = "1.0.0")
+public interface CooldownConfiguration<C> {
+
+    /**
+     * Returns a new configuration builder.
+     *
+     * @param <C> command sender type
+     * @return the builder
+     */
+    static <C> ImmutableCooldownConfiguration.@NonNull RepositoryBuildStage<C> builder() {
+        return ImmutableCooldownConfiguration.builder();
+    }
+
+    /**
+     * Returns the repository used to store cooldowns.
+     *
+     * @return the repository
+     */
+    @NonNull CooldownRepository<C> repository();
+
+    /**
+     * Returns the active cooldown listeners.
+     *
+     * <p>The active cooldown listeners are invoked when a cooldown is preventing a sender from executing a command.</p>
+     *
+     * @return active cooldown listeners
+     */
+    @NonNull List<CooldownActiveListener<C>> activeCooldownListeners();
+
+    /**
+     * Returns the creation listeners.
+     *
+     * <p>The creation listeners are invoked when a new cooldown is created.</p>
+     *
+     * @return creation listeners
+     */
+    @NonNull List<CooldownCreationListener<C>> creationListeners();
+
+    /**
+     * Returns a predicate that determines whether the {@link CommandContext}
+     * should bypass the cooldown requirement.
+     *
+     * <p>The default implementation always returns {@code false}</p>
+     *
+     * @return predicate that determines whether cooldowns should be skipped
+     */
+    default @NonNull Predicate<@NonNull CommandContext<C>> bypassCooldown() {
+        return context -> false;
+    }
+
+    /**
+     * Returns the clock used to calculate the current time.
+     *
+     * @return the clock
+     */
+    default @NonNull Clock clock() {
+        return Clock.systemUTC();
+    }
+
+    /**
+     * Returns the factory that produces cooldown profiles.
+     *
+     * @return cooldown profile factory
+     */
+    default @NonNull CooldownProfileFactory profileFactory() {
+        return new StandardCooldownProfileFactory(this);
+    }
+
+    /**
+     * Returns the function that determines the fallback {@link CooldownGroup} in case no group has been provided
+     * to the {@link Cooldown}.
+     *
+     * @return the fallback group function
+     */
+    default @NonNull Function<@NonNull Command<C>, @NonNull CooldownGroup> fallbackGroup() {
+        return CooldownGroup::command;
+    }
+}