Rocket.Chat/app/livechat/server/api/v1/agent.js

import { Meteor } from 'meteor/meteor';
import { Match, check } from 'meteor/check';

import { API } from '../../../../api/server';
import { findRoom, findGuest, findAgent, findOpenRoom } from '../lib/livechat';
import { Livechat } from '../../lib/Livechat';

API.v1.addRoute('livechat/agent.info/:rid/:token', {
	get() {
		try {
			check(this.urlParams, {
				rid: String,
				token: String,
			});

			const visitor = findGuest(this.urlParams.token);
			if (!visitor) {
				throw new Meteor.Error('invalid-token');
			}

			const room = findRoom(this.urlParams.token, this.urlParams.rid);
			if (!room) {
				throw new Meteor.Error('invalid-room');
			}

			const agent = room && room.servedBy && findAgent(room.servedBy._id);
			if (!agent) {
				throw new Meteor.Error('invalid-agent');
			}

			return API.v1.success({ agent });
		} catch (e) {
			return API.v1.failure(e);
		}
	},
});

API.v1.addRoute('livechat/agent.next/:token', {
	get() {
		try {
			check(this.urlParams, {
				token: String,
			});

			check(this.queryParams, {
				department: Match.Maybe(String),
			});

			const { token } = this.urlParams;
			const room = findOpenRoom(token);
			if (room) {
				return API.v1.success();
			}

			let { department } = this.queryParams;
			if (!department) {
				const requireDeparment = Livechat.getRequiredDepartment();
				if (requireDeparment) {
					department = requireDeparment._id;
				}
			}

			const agentData = Promise.await(Livechat.getNextAgent(department));
			if (!agentData) {
				throw new Meteor.Error('agent-not-found');
			}

			const agent = findAgent(agentData.agentId);
			if (!agent) {
				throw new Meteor.Error('invalid-agent');
			}

			return API.v1.success({ agent });
		} catch (e) {
			return API.v1.failure(e);
		}
	},
});