Overview

bot-express is a chatbot development framework to build tailer-made chatbot lightning fast. Developers can extend the chatbot capability just by adding skills.

Features

• NLU integration.
• Context aware behavior.
• Auto parameter collection based on skill.
• Auto language translation.
• Support multiple messengers.
• Available as npm package.

Architecture

Components

A chatbot based on bot-express is composed of following components.

• Messenger
• NLU
• Bot instance（Node.js app based on bot-express）

Developers can extend the chatbot capability just by adding skills. 1 skill is simply composed by 1 script file. Developers can make chatbot more painstaking by creating polished skill and make it more capable by adding wide variety of skills.

Basic workflow

The very basic workflow of bot-express based chatbot is following.

1. A user sends message to a chatbot.
2. bot-express forwards the message to NLU and identifies the intent of the message.
3. bot-express pickup a skill corresponding to the identified intent.
4. The skill is executed. ex: Reply to the user, Update the database, Send signal to IoT devices.

bot-express continues interaction with the user until it accomplish the mission defined by the skill. The interaction is conducted to respond/collect required information. Developers can configure the parser and reaction for every single parameters to collect and they are automatically applied to each messages from the user.

Getting Started

bot-express can be installed by installing a npm package just like below.

$ npm install --save bot-express

Running through the tutorial is a fastest way to learn bot-express since it covers the most important configurations step by step.

Tutorial: Create pizza delivery reception bot using bot-express

Also take a glance at sample_skill directory which contains some sample skills.

Sample skills

Reference

As for the complete configurations, spec of the skill script and API, please refer to the following document.

https://nkjm.github.io/bot-express

Supported Messengers

• LINE
• Facebook Messenger

Supported NLU

• Dialogflow

Debug

Set environment variable DEBUG to "bot-express:*" to activate full debugging. In production environment, setting "bot-express:skill-status" is recommended. To make this debugging work properly when you use redis as memory store, you need to enable Redis Keyspace Notification like following to subscribe expired event.

$ redis-cli config set notify-keyspace-events Ex

Also need to enable keyspace_notification of memory option in index.js like follows.

memory: {
    type: "redis",
    options: {
        url: process.env.REDIS_URL,
        keyspace_notification: true // default is false.
    }
}

Limitation

Webhook supports following event at present.

LINE

• message
• follow
• unfollow
• join
• leave
• postback
• beacon

Facebook

• messages
• messaging-postbacks

If you deploy cluster of bot-express based application, you need to use redis as context store. Please refer to the document for detail.