cloud-discord4j

Cloud integration for Discord4J slash commands.

An example bot using cloud-discord4j can be found here.

Installation

Cloud for Discord4J is available through Maven Central.

MavenGradle (Kotlin)Gradle (Groovy)

<dependencies>
    <dependency>
        <groupId>org.incendo</groupId>
        <artifactId>cloud-discord4j</artifactId>
        <version>1.0.0-beta.3</version>
    </dependency>
</dependencies>

implementation("org.incendo:cloud-discord4j:1.0.0-beta.3")

implementation 'org.incendo:cloud-discord4j:1.0.0-beta.3'

Usage

Command Manager

// Using the "native" Discord4JInteraction sender type:
Discord4JCommandManager<Discord4JInteraction> commandManager = new Discord4JCommandManager<>(
    executionCoordinator,
    Discord4JInteraction.InteractionMapper.identity()
);

// Using a custom sender type:
Discord4JCommandManager<YourSenderType> commandManager = new Discord4JCommandManager<>(
    executionCoordinator,
    interaction -> yourSenderType
);

where executionCoordinator is an ExecutionCoordinator instance.

You then register the command manager as a Discord4J event listener. Example:

discordClient.withGateway(commandManager::installEventListener).block();

The event listener handles command synchronization, command execution and autocompletion.

Parsers

Mappings to all existing option types are supported:

• INTEGER: IntegerParser
• NUMBER: DoubleParser
• BOOLEAN: BooleanParser
• STRING: StringParser
• USER: Discord4JParser.userParser()
• CHANNEL: Discord4JParser.channelParser()
• ROLE: Discord4JParser.roleParser()
• MENTIONABLE: Discord4JParser.mentionableParser()
• ATTACHMENT: Discord4JParser.attachmentParser()

Subcommands and subcommand groups are mapped to Cloud literals. Other parsers are by default be mapped to OptionType.STRING.

Choices

The suggestion providers will be invoked for option types that support auto completions. You may also use constant choices by using DiscordChoices as the suggestion provider. Example:

commandBuilder.required(
    "integer",
    integerParser(),
    DiscordChoices.integers(1, 2, 3)
)

Choices may be used for custom parsers that get mapped to OptionType.STRING.

Reactive Execution Handlers

As Discord4J makes extensive use of reactor classes it is recommended that you make use of Discord4JCommandExecutionHandler.reactiveHandler(Function), which allows you to return a Producer from your command handler. Example:

 .handler(reactiveHandler(context -> {
    final Discord4JInteraction interaction = context.sender();
    final String message = context.get(COMPONENT_MESSAGE);
    return interaction.commandEvent()
            .map(event -> (Mono<?>) event.reply(message).withEphemeral(true))
            .orElseGet(Mono::empty);
})

If you use annotated commands then you may return CompletableFuture<Void>. You’ll have to convert the reactor classes to futures. Example:

@Command("command")
public CompletableFuture<Void> command(
  final Discord4JInteraction interaction
) {
        return interaction.commandEvent()
                .map(event -> (Mono<?>) event.reply("Hello world"))
                .orElseGet(Mono::empty)
                .then()
                .toFuture();
}

Command Scopes

You may choose where a command is registered to by using CommandScope. You apply the scope to the command builder using:

// Available everywhere (DMs, guilds, etc):
commandBuilder.apply(CommandScope.global());

// Available in all guilds:
commandBuilder.apply(CommandScope.guilds());

// Available in specific guilds:
commandBuilder.apply(CommandScope.guilds(some, guild, ids));

You may implement custom filtering by overriding the command scope predicate for the command factory:

commandManager.commandFactory()
        .commandScopePredicate((node, scope) -> yourLogicHere);

Annotations:

If using annotated commands you may use the @CommandScope annotation. You must first install the builder modifier:

CommandScopeBuilderModifier.install(annotationParser);

You may then use the annotation:

@CommandScope(guilds = { 1337 })
@Command("command")
public void yourCommand() { /* ... */ }

Permissions

You may set the default permissions by using DiscordPermission.of(Long) as the command permission. Example:

// Using Discord4J's PermissionSet helper class.
commandBuilder.permission(DiscordPermission.of(PermissionSet.all().getRawValue()))

You may use ordinary permissions by setting the permission function in Discord4JCommandManager.

Settings

You may modify certain behaviors using the DiscordSettings. You may do this by accessing the Configurable<DiscordSetting> instance using Discord4JCommandManager.discordSettings().