Prg-chatbot - Facebook Messenger platform framework

Framework for building reusable chatbot components. Routing, Keyword recognition is built-in.

Requirements and installation

requires mongoose > 4.0
requires nodejs > 6.0
requires express > 4.0
requires body-parser > 1.10

$ npm i -S prg-chatbot

Basic setup with Express

It's easy. This basic example can handle everything. Note, that the handler is STRICTLY SYNCHRONOUS.

const express = require('express');
const bodyParser = require('body-parser');
const { createRouter, createProcessor } = require('prg-chatbot/express');

const handler = (req, res, postBack) => {
    res.typingOn()
        .wait();

    switch (req.action()) {
        case 'hello':
            res.text('Hello world');
            return;
        default:
            // send one quick reply
            res.text('What you want?', {
                hello: 'Say hello world'
            })
    }
};

const processor = createProcessor(handler, {
    pageToken: 'stringhere',
    appSecret: 'botappsecret'
});

// app = express();

app.use('/bot', createRouter(processor));

Processing asynchronous actions

How to deal with asynchronous action, when handlers are synchronous? Use postBack(action[, data])).

const handler = (req, res, postBack) => {
    switch (req.action()) {
        case 'downloaded':
            const { data, err } = req.action(true);

            if (err && err.code === 400) {
                res.text('Image size exceeded');
            } else if (err) {
                res.text('Upload failed');
            } else {
                res.text('Hello world');
            }
            return;
        default:
            if (req.isImage()) {
                const resolve = postBack.wait(); // usefull for tests
                bufferloader(req.attachmentUrl(), 1000000)
                    .then(buffer => resolve('downloaded', { data: buffer }))
                    .catch(err => resolve('donwloaded', { err }))
            }
    }
};

Experimental: Router

Router is the way to handle strucured complex bots

const { Router } = require('prg-chatbot');

const app = new Router();

// middleware
app.use('*', (req, res, postBack, next) => {
    res.typingOn()
        .wait();
    next();
});

app.use('actionName', (req, res) => {
    if (req.state.secondAttempt) {
        res.text('hello again');
    } else {
        res.text('hello')
            .setState({ secondAttempt: true });
    }
});

app.use('textAction', /keyword|two-words?/, (req, res) => {
    res.text('Welcome', {
        actionName: 'Say hello' // quick reply
    })
});

API

Classes

Request
Responder
ButtonTemplate ⇐ BaseTemplate
ReceiptTemplate ⇐ BaseTemplate
GenericTemplate ⇐ ButtonTemplate
Router ⇐ ReducerWrapper
ReducerWrapper ⇐ EventEmitter
Tester
ResponseAssert
AnyResponseAssert
Settings

Functions

bufferloader(url, [limit], [limitJustByBody], [redirCount]) ⇒: Downloads a file from url into a buffer. Supports size limits and redirects.
attachmentType(response, type, [message]) ⇒ boolean: Checks attachment type
isText(response, [message]) ⇒ boolean: Checks, that response is a text
contains(response, search, [message]) ⇒ boolean: Checks, that text contain a message
quickReplyAction(response, action, [message]) ⇒ boolean: Checks quick response action
templateType(response, expectedType, [message]) ⇒ boolean: Checks template type
waiting(response, [message]) ⇒ boolean: Looks for waiting message

Request

Kind: global class

Request
- new Request()
- .senderId
- .recipientId
- .pageId
- .state
- .isAttachment() ⇒ boolean
- .isImage([attachmentIndex]) ⇒ boolean
- .isFile([attachmentIndex]) ⇒ boolean
- .attachment([attachmentIndex]) ⇒ object | null
- .attachmentUrl([attachmentIndex]) ⇒ string | null
- .isMessage() ⇒ boolean
- .text([tokenized]) ⇒ string
- .quickReply([getData]) ⇒ null | string | object
- .isPostBack() ⇒ boolean
- .isReferral() ⇒ boolean
- .isOptin() ⇒ boolean
- .action([getData]) ⇒ null | string | object
- .postBack([getData]) ⇒ null | string | object

new Request()

Instance of {Request} class is passed as first parameter of handler (req)

request.senderId

Kind: instance property of Request
Properties

Name	Type	Description
senderId	`string`	sender.id from the event

request.recipientId

Kind: instance property of Request
Properties

Name	Type	Description
recipientId	`string`	recipient.id from the event

request.pageId

Kind: instance property of Request
Properties

Name	Type	Description
pageId	`string`	page identifier from the event

request.state

Kind: instance property of Request
Properties

Name	Type	Description
state	`object`	current state of the conversation