Rocket.Chat/app/lib/server/methods/sendMessage.js

import { Meteor } from 'meteor/meteor';
import { check } from 'meteor/check';
import { Random } from 'meteor/random';
import { TAPi18n } from 'meteor/rocketchat:tap-i18n';
import moment from 'moment';

import { hasPermission } from '../../../authorization';
import { metrics } from '../../../metrics';
import { settings } from '../../../settings';
import { Notifications } from '../../../notifications';
import { messageProperties } from '../../../ui-utils';
import { Users, Messages } from '../../../models';
import { sendMessage } from '../functions';
import { RateLimiter } from '../lib';
import { canSendMessage } from '../../../authorization/server';
import { SystemLogger } from '../../../logger/server';

export function executeSendMessage(uid, message) {
	if (message.tmid && !settings.get('Threads_enabled')) {
		throw new Meteor.Error('error-not-allowed', 'not-allowed', {
			method: 'sendMessage',
		});
	}

	if (message.ts) {
		const tsDiff = Math.abs(moment(message.ts).diff());
		if (tsDiff > 60000) {
			throw new Meteor.Error('error-message-ts-out-of-sync', 'Message timestamp is out of sync', {
				method: 'sendMessage',
				message_ts: message.ts,
				server_ts: new Date().getTime(),
			});
		} else if (tsDiff > 10000) {
			message.ts = new Date();
		}
	} else {
		message.ts = new Date();
	}

	if (message.msg) {
		const adjustedMessage = messageProperties.messageWithoutEmojiShortnames(message.msg);

		if (messageProperties.length(adjustedMessage) > settings.get('Message_MaxAllowedSize')) {
			throw new Meteor.Error('error-message-size-exceeded', 'Message size exceeds Message_MaxAllowedSize', {
				method: 'sendMessage',
			});
		}
	}

	const user = Users.findOneById(uid, {
		fields: {
			username: 1,
			type: 1,
			...!!settings.get('Message_SetNameToAliasEnabled') && { name: 1 },
		},
	});
	let { rid } = message;

	// do not allow nested threads
	if (message.tmid) {
		const parentMessage = Messages.findOneById(message.tmid);
		message.tmid = parentMessage.tmid || message.tmid;
		rid = parentMessage.rid;
	}

	if (!rid) {
		throw new Error('The \'rid\' property on the message object is missing.');
	}

	try {
		const room = canSendMessage(rid, { uid, username: user.username, type: user.type });
		if (message.alias == null && settings.get('Message_SetNameToAliasEnabled')) {
			message.alias = user.name;
		}

		metrics.messagesSent.inc(); // TODO This line needs to be moved to it's proper place. See the comments on: https://github.com/RocketChat/Rocket.Chat/pull/5736
		return sendMessage(user, message, room, false);
	} catch (error) {
		if (error === 'error-not-allowed') {
			throw new Meteor.Error('error-not-allowed');
		}

		SystemLogger.error('Error sending message:', error);

		Notifications.notifyUser(uid, 'message', {
			_id: Random.id(),
			rid: message.rid,
			ts: new Date(),
			msg: TAPi18n.__(error, {}, user.language),
		});
	}
}

Meteor.methods({
	sendMessage(message) {
		check(message, Object);

		const uid = Meteor.userId();
		if (!uid) {
			throw new Meteor.Error('error-invalid-user', 'Invalid user', {
				method: 'sendMessage',
			});
		}

		return executeSendMessage(uid, message);
	},
});
// Limit a user, who does not have the "bot" role, to sending 5 msgs/second
RateLimiter.limitMethod('sendMessage', 5, 1000, {
	userId(userId) {
		return !hasPermission(userId, 'send-many-messages');
	},
});