Plugins

Plugins run code around your application. At boot, on login, or in response to runtime events. They are not called directly from your commands.

Services vs plugins

Use a service when your code needs to call something: context.services.db.query(...).

Use a plugin when something needs to happen on its own: “run a health check on startup”, “reject all commands during maintenance”, “start a recurring task”.

What plugins can do

Plugins have access to the full lifecycle:

Hook	When it runs
setup()	During initialization, before login. Can register commands, preconditions, handlers, and events.
beforeLogin()	After setup, immediately before establishing the Discord WebSocket connection.
afterLogin()	After the bot is online and the ready event has the potential to fire.

Plugins also receive the diagnostics hub, enabling them to subscribe to runtime events or register custom diagnostic sources.

Registering plugins

Plugins are explicitly wired in src/plugins/index.ts:

src/plugins/index.ts

import { createDevtoolsPlugin } from "@bight-ts/plugin-devtools";

export const plugins = [
  createDevtoolsPlugin({
    ownerIds: ["123456789"],
  }),
];

There is no auto-injection. Every active plugin is visible in this array.

Writing a custom plugin

src/plugins/welcome-log.ts

import { definePlugin } from "@bight-ts/core";

export const welcomeLogPlugin = definePlugin({
  name: "welcome-log",

  afterLogin({ context }) {
    context.logger.info("Bot is online and ready.");
  },
});

Plugins can register commands, handlers, and preconditions through the setup hook’s helper methods (addCommand, addPrecondition, addGlobalPrecondition, etc). See the plugin reference for the full BightPluginSetup interface.

Conditional plugins

definePlugins() filters out falsey values, making conditional inclusion clean:

src/plugins/index.ts

import { definePlugins } from "@bight-ts/core";

export const plugins = definePlugins([
  createDevtoolsPlugin({ ownerIds: ["123456789"] }),
  process.env.ENABLE_SCHEDULER === "true" && schedulerPlugin,
  process.env.NODE_ENV === "production" && errorReporterPlugin,
]);