discord.js-selfbot-v13/src/client/Client.js
2022-05-06 21:17:20 +07:00

751 lines
26 KiB
JavaScript

'use strict';
const process = require('node:process');
const { setInterval, setTimeout } = require('node:timers');
const { Collection } = require('@discordjs/collection');
const RichPresence = require('discord-rpc-contructor');
const BaseClient = require('./BaseClient');
const ActionsManager = require('./actions/ActionsManager');
const ClientVoiceManager = require('./voice/ClientVoiceManager');
const WebSocketManager = require('./websocket/WebSocketManager');
const { Error, TypeError, RangeError } = require('../errors');
const BaseGuildEmojiManager = require('../managers/BaseGuildEmojiManager');
const ChannelManager = require('../managers/ChannelManager');
const ClientUserSettingManager = require('../managers/ClientUserSettingManager');
const GuildManager = require('../managers/GuildManager');
const RelationshipsManager = require('../managers/RelationshipsManager');
const UserManager = require('../managers/UserManager');
const ShardClientUtil = require('../sharding/ShardClientUtil');
const ClientPresence = require('../structures/ClientPresence');
const GuildPreview = require('../structures/GuildPreview');
const GuildTemplate = require('../structures/GuildTemplate');
const Invite = require('../structures/Invite');
const { Sticker } = require('../structures/Sticker');
const StickerPack = require('../structures/StickerPack');
const VoiceRegion = require('../structures/VoiceRegion');
const Webhook = require('../structures/Webhook');
const Widget = require('../structures/Widget');
const { Events, InviteScopes, Status } = require('../util/Constants');
const DataResolver = require('../util/DataResolver');
const Intents = require('../util/Intents');
const Options = require('../util/Options');
const Permissions = require('../util/Permissions');
const DiscordAuthWebsocket = require('../util/RemoteAuth');
const Sweepers = require('../util/Sweepers');
// Patch
/**
* The main hub for interacting with the Discord API, and the starting point for any bot.
* @extends {BaseClient}
*/
class Client extends BaseClient {
/**
* @param {ClientOptions} options Options for the client
*/
constructor(options = {}) {
super(options);
const data = require('node:worker_threads').workerData ?? process.env;
const defaults = Options.createDefault();
if (this.options.shards === defaults.shards) {
if ('SHARDS' in data) {
this.options.shards = JSON.parse(data.SHARDS);
}
}
if (this.options.shardCount === defaults.shardCount) {
if ('SHARD_COUNT' in data) {
this.options.shardCount = Number(data.SHARD_COUNT);
} else if (Array.isArray(this.options.shards)) {
this.options.shardCount = this.options.shards.length;
}
}
const typeofShards = typeof this.options.shards;
if (typeofShards === 'undefined' && typeof this.options.shardCount === 'number') {
this.options.shards = Array.from({ length: this.options.shardCount }, (_, i) => i);
}
if (typeofShards === 'number') this.options.shards = [this.options.shards];
if (Array.isArray(this.options.shards)) {
this.options.shards = [
...new Set(
this.options.shards.filter(item => !isNaN(item) && item >= 0 && item < Infinity && item === (item | 0)),
),
];
}
this._validateOptions();
/**
* Functions called when a cache is garbage collected or the Client is destroyed
* @type {Set<Function>}
* @private
*/
this._cleanups = new Set();
/**
* The finalizers used to cleanup items.
* @type {FinalizationRegistry}
* @private
*/
this._finalizers = new FinalizationRegistry(this._finalize.bind(this));
/**
* The WebSocket manager of the client
* @type {WebSocketManager}
*/
this.ws = new WebSocketManager(this);
/**
* The action manager of the client
* @type {ActionsManager}
* @private
*/
this.actions = new ActionsManager(this);
/**
* The voice manager of the client
* @type {ClientVoiceManager}
*/
this.voice = new ClientVoiceManager(this);
/**
* Shard helpers for the client (only if the process was spawned from a {@link ShardingManager})
* @type {?ShardClientUtil}
*/
this.shard = process.env.SHARDING_MANAGER
? ShardClientUtil.singleton(this, process.env.SHARDING_MANAGER_MODE)
: null;
/**
* All of the {@link User} objects that have been cached at any point, mapped by their ids
* @type {UserManager}
*/
this.users = new UserManager(this);
// Patch
/**
* All of the relationships {@link User}
* @type {RelationshipsManager}
*/
this.relationships = new RelationshipsManager(this);
/**
* All of the settings {@link Object}
* @type {ClientUserSettingManager}
*/
this.setting = new ClientUserSettingManager(this);
/**
* All of the guilds the client is currently handling, mapped by their ids -
* as long as sharding isn't being used, this will be *every* guild the bot is a member of
* @type {GuildManager}
*/
this.guilds = new GuildManager(this);
/**
* All of the {@link Channel}s that the client is currently handling, mapped by their ids -
* as long as sharding isn't being used, this will be *every* channel in *every* guild the bot
* is a member of. Note that DM channels will not be initially cached, and thus not be present
* in the Manager without their explicit fetching or use.
* @type {ChannelManager}
*/
this.channels = new ChannelManager(this);
/**
* The sweeping functions and their intervals used to periodically sweep caches
* @type {Sweepers}
*/
this.sweepers = new Sweepers(this, this.options.sweepers);
/**
* The presence of the Client
* @private
* @type {ClientPresence}
*/
this.presence = new ClientPresence(this, this.options.presence);
Object.defineProperty(this, 'token', { writable: true });
if (!this.token && 'DISCORD_TOKEN' in process.env) {
/**
* Authorization token for the logged in bot.
* If present, this defaults to `process.env.DISCORD_TOKEN` when instantiating the client
* <warn>This should be kept private at all times.</warn>
* @type {?string}
*/
this.token = process.env.DISCORD_TOKEN;
} else {
this.token = null;
}
/**
* User that the client is logged in as
* @type {?ClientUser}
*/
this.user = null;
/**
* The application of this bot
* @type {?ClientApplication}
*/
this.application = null;
/**
* Time at which the client was last regarded as being in the `READY` state
* (each time the client disconnects and successfully reconnects, this will be overwritten)
* @type {?Date}
*/
this.readyAt = null;
/**
* Password cache
* @type {?string}
*/
this.password = null;
if (this.options.messageSweepInterval > 0) {
process.emitWarning(
'The message sweeping client options are deprecated, use the global sweepers instead.',
'DeprecationWarning',
);
this.sweepMessageInterval = setInterval(
this.sweepMessages.bind(this),
this.options.messageSweepInterval * 1_000,
).unref();
}
}
/**
* All custom emojis that the client has access to, mapped by their ids
* @type {BaseGuildEmojiManager}
* @readonly
*/
get emojis() {
const emojis = new BaseGuildEmojiManager(this);
for (const guild of this.guilds.cache.values()) {
if (guild.available) for (const emoji of guild.emojis.cache.values()) emojis.cache.set(emoji.id, emoji);
}
return emojis;
}
/**
* Timestamp of the time the client was last `READY` at
* @type {?number}
* @readonly
*/
get readyTimestamp() {
return this.readyAt?.getTime() ?? null;
}
/**
* How long it has been since the client last entered the `READY` state in milliseconds
* @type {?number}
* @readonly
*/
get uptime() {
return this.readyAt ? Date.now() - this.readyAt : null;
}
/**
* Update Cloudflare Cookie and Discord Fingerprint
*/
async updateCookie() {
/* Auto find fingerprint and add Cookie */
let cookie = '';
await require('axios')({
method: 'get',
url: 'https://discord.com/api/v9/experiments',
headers: this.options.http.headers,
})
.then(res => {
if (!('set-cookie' in res.headers)) return;
res.headers['set-cookie'].map(line => {
line.split('; ').map(arr => {
if (
arr.startsWith('Expires') ||
arr.startsWith('Path') ||
arr.startsWith('Domain') ||
arr.startsWith('HttpOnly') ||
arr.startsWith('Secure') ||
arr.startsWith('Max-Age') ||
arr.startsWith('SameSite')
) {
return null;
} else {
cookie += `${arr}; `;
return true;
}
});
return true;
});
this.options.http.headers.Cookie = `${cookie}locale=en`;
this.options.http.headers['x-fingerprint'] = res.data.fingerprint;
this.emit(Events.DEBUG, `Added Cookie: ${cookie}`);
this.emit(Events.DEBUG, `Added Fingerprint: ${res.data.fingerprint}`);
})
.catch(err => {
this.emit(Events.DEBUG, `Finding Cookie and Fingerprint failed: ${err.message}`);
});
}
/**
* Logs the client in, establishing a WebSocket connection to Discord.
* @param {string} [token=this.token] Token of the account to log in with
* @returns {Promise<string>} Token of the account used
* @example
* client.login('my token');
*/
async login(token = this.token) {
if (!token || typeof token !== 'string') throw new Error('TOKEN_INVALID');
this.token = token = token.replace(/^(Bot|Bearer)\s*/i, '');
this.emit(
Events.DEBUG,
`Provided token: ${token
.split('.')
.map((val, i) => (i > 1 ? val.replace(/./g, '*') : val))
.join('.')}`,
);
if (this.options.autoCookie) {
await this.updateCookie();
}
if (this.options.presence) {
this.options.ws.presence = this.presence._parse(this.options.presence);
}
this.emit(Events.DEBUG, 'Preparing to connect to the gateway...');
try {
await this.ws.connect();
return this.token;
} catch (error) {
this.destroy();
throw error;
}
}
/**
* Sign in with the QR code on your phone.
* @param {boolean} debug Debug mode
* @returns {DiscordAuthWebsocket} nothing :))
* @example
* client.QRLogin();
*/
QRLogin(debug = false) {
console.log(this.options);
const QR = new DiscordAuthWebsocket(this, debug);
this.emit(Events.DEBUG, `Preparing to connect to the gateway`, QR);
return QR;
}
/**
* Returns whether the client has logged in, indicative of being able to access
* properties such as `user` and `application`.
* @returns {boolean}
*/
isReady() {
return this.ws.status === Status.READY;
}
/**
* Logs out, terminates the connection to Discord, and destroys the client.
* @returns {void}
*/
destroy() {
super.destroy();
for (const fn of this._cleanups) fn();
this._cleanups.clear();
if (this.sweepMessageInterval) clearInterval(this.sweepMessageInterval);
this.sweepers.destroy();
this.ws.destroy();
this.token = null;
}
/**
* Options used when fetching an invite from Discord.
* @typedef {Object} ClientFetchInviteOptions
* @property {Snowflake} [guildScheduledEventId] The id of the guild scheduled event to include with
* the invite
*/
/**
* Obtains an invite from Discord.
* @param {InviteResolvable} invite Invite code or URL
* @param {ClientFetchInviteOptions} [options] Options for fetching the invite
* @returns {Promise<Invite>}
* @example
* client.fetchInvite('https://discord.gg/djs')
* .then(invite => console.log(`Obtained invite with code: ${invite.code}`))
* .catch(console.error);
*/
async fetchInvite(invite, options) {
const code = DataResolver.resolveInviteCode(invite);
const data = await this.api.invites(code).get({
query: { with_counts: true, with_expiration: true, guild_scheduled_event_id: options?.guildScheduledEventId },
});
return new Invite(this, data);
}
// TODO: Remove this in the next major version
reddemNitro(code) {
process.emitWarning(
'This function will no longer be available after a major update. Using .redeemNitro()\nSee here: https://github.com/aiko-chan-ai/discord.js-selfbot-v13/pull/59',
'DeprecationWarning',
);
return this.redeemNitro(code);
}
/**
* Get Nitro
* @param {string<NitroCode>} nitro Nitro Code
* discordapp.com/gifts/code | discord.gift/code
* @returns {Promise}
*/
async redeemNitro(nitro) {
if (typeof nitro !== 'string') throw new Error('INVALID_NITRO');
const regexNitro = /discord(?:(?:app)?\.com\/gifts|\.gift)\/([\w-]{2,255})/gi;
const code = DataResolver.resolveCode(nitro, regexNitro);
// https://discord.com/api/v9/entitlements/gift-codes/{code}/redeem
const data = await this.api.entitlements['gift-codes'](code).redeem.post({ data: {} });
return data;
}
/**
* Obtains a template from Discord.
* @param {GuildTemplateResolvable} template Template code or URL
* @returns {Promise<GuildTemplate>}
* @example
* client.fetchGuildTemplate('https://discord.new/FKvmczH2HyUf')
* .then(template => console.log(`Obtained template with code: ${template.code}`))
* .catch(console.error);
*/
async fetchGuildTemplate(template) {
const code = DataResolver.resolveGuildTemplateCode(template);
const data = await this.api.guilds.templates(code).get();
return new GuildTemplate(this, data);
}
/**
* Obtains a webhook from Discord.
* @param {Snowflake} id The webhook's id
* @param {string} [token] Token for the webhook
* @returns {Promise<Webhook>}
* @example
* client.fetchWebhook('id', 'token')
* .then(webhook => console.log(`Obtained webhook with name: ${webhook.name}`))
* .catch(console.error);
*/
async fetchWebhook(id, token) {
const data = await this.api.webhooks(id, token).get();
return new Webhook(this, { token, ...data });
}
/**
* Obtains the available voice regions from Discord.
* @returns {Promise<Collection<string, VoiceRegion>>}
* @example
* client.fetchVoiceRegions()
* .then(regions => console.log(`Available regions are: ${regions.map(region => region.name).join(', ')}`))
* .catch(console.error);
*/
async fetchVoiceRegions() {
const apiRegions = await this.api.voice.regions.get();
const regions = new Collection();
for (const region of apiRegions) regions.set(region.id, new VoiceRegion(region));
return regions;
}
/**
* Obtains a sticker from Discord.
* @param {Snowflake} id The sticker's id
* @returns {Promise<Sticker>}
* @example
* client.fetchSticker('id')
* .then(sticker => console.log(`Obtained sticker with name: ${sticker.name}`))
* .catch(console.error);
*/
async fetchSticker(id) {
const data = await this.api.stickers(id).get();
return new Sticker(this, data);
}
/**
* Obtains the list of sticker packs available to Nitro subscribers from Discord.
* @returns {Promise<Collection<Snowflake, StickerPack>>}
* @example
* client.fetchPremiumStickerPacks()
* .then(packs => console.log(`Available sticker packs are: ${packs.map(pack => pack.name).join(', ')}`))
* .catch(console.error);
*/
async fetchPremiumStickerPacks() {
const data = await this.api('sticker-packs').get();
return new Collection(data.sticker_packs.map(p => [p.id, new StickerPack(this, p)]));
}
/**
* A last ditch cleanup function for garbage collection.
* @param {Function} options.cleanup The function called to GC
* @param {string} [options.message] The message to send after a successful GC
* @param {string} [options.name] The name of the item being GCed
* @private
*/
_finalize({ cleanup, message, name }) {
try {
cleanup();
this._cleanups.delete(cleanup);
if (message) {
this.emit(Events.DEBUG, message);
}
} catch {
this.emit(Events.DEBUG, `Garbage collection failed on ${name ?? 'an unknown item'}.`);
}
}
/**
* Sweeps all text-based channels' messages and removes the ones older than the max message lifetime.
* If the message has been edited, the time of the edit is used rather than the time of the original message.
* @param {number} [lifetime=this.options.messageCacheLifetime] Messages that are older than this (in seconds)
* will be removed from the caches. The default is based on {@link ClientOptions#messageCacheLifetime}
* @returns {number} Amount of messages that were removed from the caches,
* or -1 if the message cache lifetime is unlimited
* @example
* // Remove all messages older than 1800 seconds from the messages cache
* const amount = client.sweepMessages(1800);
* console.log(`Successfully removed ${amount} messages from the cache.`);
*/
sweepMessages(lifetime = this.options.messageCacheLifetime) {
if (typeof lifetime !== 'number' || isNaN(lifetime)) {
throw new TypeError('INVALID_TYPE', 'lifetime', 'number');
}
if (lifetime <= 0) {
this.emit(Events.DEBUG, "Didn't sweep messages - lifetime is unlimited");
return -1;
}
const messages = this.sweepers.sweepMessages(Sweepers.outdatedMessageSweepFilter(lifetime)());
this.emit(Events.DEBUG, `Swept ${messages} messages older than ${lifetime} seconds`);
return messages;
}
/**
* Obtains a guild preview from Discord, available for all guilds the bot is in and all Discoverable guilds.
* @param {GuildResolvable} guild The guild to fetch the preview for
* @returns {Promise<GuildPreview>}
*/
async fetchGuildPreview(guild) {
const id = this.guilds.resolveId(guild);
if (!id) throw new TypeError('INVALID_TYPE', 'guild', 'GuildResolvable');
const data = await this.api.guilds(id).preview.get();
return new GuildPreview(this, data);
}
/**
* Obtains the widget data of a guild from Discord, available for guilds with the widget enabled.
* @param {GuildResolvable} guild The guild to fetch the widget data for
* @returns {Promise<Widget>}
*/
async fetchGuildWidget(guild) {
const id = this.guilds.resolveId(guild);
if (!id) throw new TypeError('INVALID_TYPE', 'guild', 'GuildResolvable');
const data = await this.api.guilds(id, 'widget.json').get();
return new Widget(this, data);
}
/**
* Options for {@link Client#generateInvite}.
* @typedef {Object} InviteGenerationOptions
* @property {InviteScope[]} scopes Scopes that should be requested
* @property {PermissionResolvable} [permissions] Permissions to request
* @property {GuildResolvable} [guild] Guild to preselect
* @property {boolean} [disableGuildSelect] Whether to disable the guild selection
*/
/**
* Generates a link that can be used to invite the bot to a guild.
* @param {InviteGenerationOptions} [options={}] Options for the invite
* @returns {string}
* @example
* const link = client.generateInvite({
* scopes: ['applications.commands'],
* });
* console.log(`Generated application invite link: ${link}`);
* @example
* const link = client.generateInvite({
* permissions: [
* Permissions.FLAGS.SEND_MESSAGES,
* Permissions.FLAGS.MANAGE_GUILD,
* Permissions.FLAGS.MENTION_EVERYONE,
* ],
* scopes: ['bot'],
* });
* console.log(`Generated bot invite link: ${link}`);
*/
generateInvite(options = {}) {
if (typeof options !== 'object') throw new TypeError('INVALID_TYPE', 'options', 'object', true);
if (!this.application) throw new Error('CLIENT_NOT_READY', 'generate an invite link');
const query = new URLSearchParams({
client_id: this.application.id,
});
const { scopes } = options;
if (typeof scopes === 'undefined') {
throw new TypeError('INVITE_MISSING_SCOPES');
}
if (!Array.isArray(scopes)) {
throw new TypeError('INVALID_TYPE', 'scopes', 'Array of Invite Scopes', true);
}
if (!scopes.some(scope => ['bot', 'applications.commands'].includes(scope))) {
throw new TypeError('INVITE_MISSING_SCOPES');
}
const invalidScope = scopes.find(scope => !InviteScopes.includes(scope));
if (invalidScope) {
throw new TypeError('INVALID_ELEMENT', 'Array', 'scopes', invalidScope);
}
query.set('scope', scopes.join(' '));
if (options.permissions) {
const permissions = Permissions.resolve(options.permissions);
if (permissions) query.set('permissions', permissions);
}
if (options.disableGuildSelect) {
query.set('disable_guild_select', true);
}
if (options.guild) {
const guildId = this.guilds.resolveId(options.guild);
if (!guildId) throw new TypeError('INVALID_TYPE', 'options.guild', 'GuildResolvable');
query.set('guild_id', guildId);
}
return `${this.options.http.api}${this.api.oauth2.authorize}?${query}`;
}
toJSON() {
return super.toJSON({
readyAt: false,
});
}
/**
* Calls {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval} on a script
* with the client as `this`.
* @param {string} script Script to eval
* @returns {*}
* @private
*/
_eval(script) {
return eval(script);
}
async customStatusAuto(client) {
client = client ?? this;
let custom_status;
if (client.setting.rawSetting.custom_status?.text || client.setting.rawSetting.custom_status?.emoji_name) {
custom_status = new RichPresence.CustomStatus();
if (client.setting.rawSetting.custom_status.emoji_id) {
const emoji = await client.emojis.resolve(client.setting.rawSetting.custom_status.emoji_id);
if (emoji) custom_status.setDiscordEmoji(emoji);
} else {
custom_status.setUnicodeEmoji(client.setting.rawSetting.custom_status.emoji_name);
}
custom_status.setState(client.setting.rawSetting.custom_status?.text);
client.user.setPresence({
activities: custom_status
? [custom_status.toDiscord(), ...this.presence.activities.filter(a => a.type !== 'CUSTOM')]
: this.presence.activities.filter(a => a.type !== 'CUSTOM'),
status: client.setting.rawSetting.status,
});
}
}
sleep(miliseconds) {
return new Promise(r => setTimeout(r, miliseconds));
}
/**
* Validates the client options.
* @param {ClientOptions} [options=this.options] Options to validate
* @private
*/
_validateOptions(options = this.options) {
if (typeof options.intents === 'undefined') {
throw new TypeError('CLIENT_MISSING_INTENTS');
} else {
options.intents = Intents.resolve(options.intents);
}
if (typeof options.shardCount !== 'number' || isNaN(options.shardCount) || options.shardCount < 1) {
throw new TypeError('CLIENT_INVALID_OPTION', 'shardCount', 'a number greater than or equal to 1');
}
if (options.shards && !(options.shards === 'auto' || Array.isArray(options.shards))) {
throw new TypeError('CLIENT_INVALID_OPTION', 'shards', "'auto', a number or array of numbers");
}
if (options.shards && !options.shards.length) throw new RangeError('CLIENT_INVALID_PROVIDED_SHARDS');
if (typeof options.makeCache !== 'function') {
throw new TypeError('CLIENT_INVALID_OPTION', 'makeCache', 'a function');
}
if (typeof options.messageCacheLifetime !== 'number' || isNaN(options.messageCacheLifetime)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'The messageCacheLifetime', 'a number');
}
if (typeof options.messageSweepInterval !== 'number' || isNaN(options.messageSweepInterval)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'messageSweepInterval', 'a number');
}
if (typeof options.sweepers !== 'object' || options.sweepers === null) {
throw new TypeError('CLIENT_INVALID_OPTION', 'sweepers', 'an object');
}
if (typeof options.invalidRequestWarningInterval !== 'number' || isNaN(options.invalidRequestWarningInterval)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'invalidRequestWarningInterval', 'a number');
}
if (!Array.isArray(options.partials)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'partials', 'an Array');
}
if (typeof options.waitGuildTimeout !== 'number' || isNaN(options.waitGuildTimeout)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'waitGuildTimeout', 'a number');
}
if (typeof options.restWsBridgeTimeout !== 'number' || isNaN(options.restWsBridgeTimeout)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'restWsBridgeTimeout', 'a number');
}
if (typeof options.restRequestTimeout !== 'number' || isNaN(options.restRequestTimeout)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'restRequestTimeout', 'a number');
}
if (typeof options.restGlobalRateLimit !== 'number' || isNaN(options.restGlobalRateLimit)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'restGlobalRateLimit', 'a number');
}
if (typeof options.restSweepInterval !== 'number' || isNaN(options.restSweepInterval)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'restSweepInterval', 'a number');
}
if (typeof options.retryLimit !== 'number' || isNaN(options.retryLimit)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'retryLimit', 'a number');
}
if (typeof options.failIfNotExists !== 'boolean') {
throw new TypeError('CLIENT_INVALID_OPTION', 'failIfNotExists', 'a boolean');
}
if (!Array.isArray(options.userAgentSuffix)) {
throw new TypeError('CLIENT_INVALID_OPTION', 'userAgentSuffix', 'an array of strings');
}
if (
typeof options.rejectOnRateLimit !== 'undefined' &&
!(typeof options.rejectOnRateLimit === 'function' || Array.isArray(options.rejectOnRateLimit))
) {
throw new TypeError('CLIENT_INVALID_OPTION', 'rejectOnRateLimit', 'an array or a function');
}
}
}
module.exports = Client;
/**
* Emitted for general warnings.
* @event Client#warn
* @param {string} info The warning
*/
/**
* @external Collection
* @see {@link https://discord.js.org/#/docs/collection/main/class/Collection}
*/