Rocket.Chat/app/livechat/server/hooks/externalMessage.js

import { HTTP } from 'meteor/http';
import _ from 'underscore';

import { settings } from '../../../settings';
import { callbacks } from '../../../callbacks';
import { SystemLogger } from '../../../logger';
import { LivechatExternalMessage } from '../../../models/server';
import { normalizeMessageFileUpload } from '../../../utils/server/functions/normalizeMessageFileUpload';

let knowledgeEnabled = false;
let apiaiKey = '';
let apiaiLanguage = 'en';
settings.get('Livechat_Knowledge_Enabled', function(key, value) {
	knowledgeEnabled = value;
});
settings.get('Livechat_Knowledge_Apiai_Key', function(key, value) {
	apiaiKey = value;
});
settings.get('Livechat_Knowledge_Apiai_Language', function(key, value) {
	apiaiLanguage = value;
});

callbacks.add('afterSaveMessage', function(message, room) {
	// skips this callback if the message was edited
	if (!message || message.editedAt) {
		return message;
	}

	if (!knowledgeEnabled) {
		return message;
	}

	if (!(typeof room.t !== 'undefined' && room.t === 'l' && room.v && room.v.token)) {
		return message;
	}

	if (message.file) {
		message = normalizeMessageFileUpload(message);
	}

	// if the message hasn't a token, it was not sent by the visitor, so ignore it
	if (!message.token) {
		return message;
	}

	try {
		const response = HTTP.post('https://api.api.ai/api/query?v=20150910', {
			data: {
				query: message.msg,
				lang: apiaiLanguage,
				sessionId: room._id,
			},
			headers: {
				'Content-Type': 'application/json; charset=utf-8',
				Authorization: `Bearer ${ apiaiKey }`,
			},
		});

		if (response.data && response.data.status.code === 200 && !_.isEmpty(response.data.result.fulfillment.speech)) {
			LivechatExternalMessage.insert({
				rid: message.rid,
				msg: response.data.result.fulfillment.speech,
				orig: message._id,
				ts: new Date(),
			});
		}
	} catch (e) {
		SystemLogger.error('Error using Api.ai ->', e);
	}

	return message;
}, callbacks.priority.LOW, 'externalWebHook');