messenger-ruby

A simple library for supporting implementation of Facebook Messenger Bot in Ruby on Rails.

Installation

Add this line to your application's Gemfile:

gem 'messenger-ruby'

And then execute:

$ bundle

Or install it yourself as:

$ gem install messenger-ruby

Configuration

Facebook steps

• create Facebook page (skip if you want to use existing page)
• create Facebook app (skip if you want to use existing app)
• go to Facebook for Developers and get Page Access Token (step 3. Get Page Access Token from this tutorial)

Initializer

Create messenger.rb initializer in you app directory and paste Page Access Token from previous step:

# YOUR_APP/config/initializers/messenger.rb
Messenger.configure do |config|
  config.verify_token      = '<VERIFY_TOKEN>' #will be used in webhook verifiction
  config.page_access_token = '<PAGE_ACCESS_TOKEN>'
end

Routes

Add to your routes.rb:

# YOUR_APP/config/routes.rb
mount Messenger::Engine, at: "/messenger"

Controller

Create messenger_controller.rb in your controllers directory - controller has to inherit from Messenger::MessengerController:

# YOUR_APP/app/controllers/messenger_controller.rb
class MessengerController < Messenger::MessengerController
  def webhook
    #logic here
    render nothing: true, status: 200
  end
end

2XX status is necessary to not clog your bot.

If you want your controller to be named differently, please update your routes.rb with appropriate route for post /messenger/webhook request.

Bot subscription

Run your application and:

• complete step 2. Setup Webhook from this tutorial - if you mounted Messenger::Engine at /messenger and your application can be found at https://example.com, your Callback URL will be https://example.com/messenger/webhook
• visit /messenger/subscribe in your app (it's replacement for 4. Subscribe the App to the Page step) - call subscribe action anytime you want to refresh subscription of your app

Usage

To send message you need to create Messenger::Request with one of the available components and pass it to Messenger::Client::send method. You can send message only to users who subscribed to your page (e.g. sent some message before).

Messenger::Request

It's used to build parameters for Facebook API. Requires component and recipient_id.

Example usage:

Messenger::Request.new(some_component, recipient_id)

Messenger::Client

Sends requests to Facebook API. Has two methods:

• get_user_profile - requires id of existing facebook user
• send - requires Messenger::Request object

Example usage:

Messenger::Client.get_user_profile(user_id) #=> hash with name, surname and profile picture
Messenger::Client.send(request) #=> hash with message details or exception if request is incorrect

Please note that unsuccessful send will be shown in logs as Facebook API response from invalid request: ...

Elements

Elements can't be used outside of templates.

Button

Lives inside Bubble element or Button template.

Attribute	Allowed values	Required?
type	'web_url', 'postback'	✔
title	String	✔
value	String	✔

Example usage:

Messenger::Elements::Button.new(type: 'web_url', title: 'Button', value: 'http://github.com')

Bubble

Part of Generic template.

Attribute	Allowed values	Required?
title	String	✔
subtitle	String	✔*
image_url	String	✔*
buttons	Messenger::Elements::Button objects array	✔*
item_url	String	✘

* - at least one of them is required

Example usage:

Messenger::Elements::Bubble.new(title: 'First', subtitle: 'Bubble')

Address

Used by Receipt template.

Attribute	Allowed values	Required?
street_1	String	✔
street_2	String	✘
city	String	✔
postal_code	String	✔
state	String	✔
country	String	✔

Example usage:

Messenger::Elements::Address.new(
  street_1: 'Vachel Lindsay Dr',
  street_2: '',
  city: 'Springfield',
  postal_code: '62701',
  state: 'IL',
  country:'USA'
)

Adjustment

Used by Receipt template.

Attribute	Allowed values	Required?
name	String	✔
amount	Integer, greater than 0	✔

Example usage:

Messenger::Elements::Adjustment.new(name: 'Adjustment 1', amount: 20)

Item

Used by Receipt template.

Attribute	Allowed values	Required?
title	String	✔
subtilte	String	✘
quantity	Integer	✘
price	Decimal	✘
currency	String, from ISO 4217 Currency Codes	✘
image_url	String	✘

Example usage:

Messenger::Elements::Item.new(
  title: 'Cool Tshirt',
  subtitle: 'XXL White',
  quantity: 3,
  price: 34,
  currency: 'USD',
  image_url: 'http://assets.servedby-buysellads.com/p/manage/asset/id/25397'
)

Order

Used by Receipt template.

Attribute	Allowed values	Required?
order_number	String, unique per conversation	✔
currency	String, from ISO 4217 Currency Codes	✔
payment_method	String	✔
timestamp	correct timestamp (String)	✘
order_url	String	✘

Example usage:

Messenger::Elements::Order.new(
  order_number: 'R190581345',
  currency: 'USD',
  payment_method: 'Visa',
  timestamp: '1428444852',
  order_url: 'http://petersapparel.parseapp.com/order?order_id=123456'
)

Summary

Used by Receipt template.

Attribute	Allowed values	Required?
subtotal	Decimal	✘
shipping_cost	Decimal	✘
total_tax	Decimal	✘
total_cost	Decimal	✔

Example usage:

Messenger::Elements::Summary.new(subtotal: 70, shipping_cost: 20, total_tax: 10, total_cost: 100)

Components

You can find more info about what can be send in Messenger Platform Docs.

Text

Attribute	Allowed values	Required?
text	String	✔

Here is complete example on how to send sample text to the user:

if fb_params.first_entry.callback.message?
  Messenger::Client.send(
    Messenger::Request.new(
      Messenger::Elements::Text.new(text: 'some text'),
      fb_params.first_entry.sender_id
    )
  )
end

#make sure to send 200 at the end
render nothing: true, status: 200

Image

Attribute	Allowed values	Required?
url	String	✔

Sending images is simple as well:

...
Messenger::Client.send(
  Messenger::Request.new(
    Messenger::Elements::Image.new(url: 'http://lorempixel.com/400/400/cats'),
    fb_params.first_entry.sender_id
  )
)
...

Generic template

Attribute	Allowed values	Required?
elements	Array of Messenger::Elements::Bubble objects	✔

Example usage:

#define bubbles here...
bubble1 = Messenger::Elements::Bubble.new(
  title: 'Bubble 1',
  subtitle: 'Cool Bubble',
  item_url: 'http://lorempixel.com/400/400/cats',
  image_url: 'http://lorempixel.com/400/400/cats',
  buttons: [
    Messenger::Elements::Button.new(
      type: 'web_url',
      title: 'Show Website',
      value: 'https://petersapparel.parseapp.com'
    )
  ]
)

bubble2 = ...

#lets create Generic template
generic = Messenger::Templates::Generic.new(
  elements: [bubble1, bubble2]
)

#now send Generic template to the user
Messenger::Client.send(
  Messenger::Request.new(generic, fb_params.first_entry.sender_id)
)

Button template

Attribute	Allowed values	Required?
text	String	✔
buttons	Array of Messenger::Elements::Button objects	✔

Example usage:

#lets create Buttons template
buttons = Messenger::Templates::Buttons.new(
  text: 'Some Cool Text',
  buttons: [
    Messenger::Elements::Button.new(
      type: 'web_url',
      title: 'Show Website',
      value: 'https://petersapparel.parseapp.com'
    )
  ]
)

#now send Buttons template to the user
Messenger::Client.send(
  Messenger::Request.new(buttons, fb_params.first_entry.sender_id)
)

Receipt template

Attribute	Allowed values	Required?
recipient_name	String	✔
order	Messenger::Elements::Order object	✔
elements	Array of Messenger::Elements::Item objects	✔
address	Messenger::Elements::Address object	✘
summary	Messenger::Elements::Summary object	✔
adjustments	Array of Messenger::Elements::Adjustment objects	✘

Example usage:

#define order element here...
order = Messenger::Elements::Order.new(
  order_number: 'R190581345',
  currency: 'USD',
  payment_method: 'Visa',
  timestamp: '1428444852',
  order_url: 'http://petersapparel.parseapp.com/order?order_id=123456'
)

#and define all other template elements
item1 = ...
item2 = ...
address = ...
summary = ...
adjustment1 = ...
adjustment2 = ...

#lets create Receipt template
receipt = Messenger::Templates::Receipt.new(
  recipient_name: 'Random Recipient',
  order: order,
  elements: [item1, item2],
  address: address,
  summary: summary,
  adjustments: [adjustment1, adjustment2]
)

#now send Receipt template to the user
Messenger::Client.send(
  Messenger::Request.new(receipt, fb_params.first_entry.sender_id)
)

Entries

According to Facebook documentation, there is possibility that you can receive multiple entries and multiple messagings. That's why we made it easy for you to iterate over entries and messagings, but we've also created first_entry method that returns first entry in entry array, because that is the most common case.

Example usage:

fb_params.entries.each do |entry|
  entry.messagings.each do |messaging|
    if messaging.callback.message?
      Messenger::Client.send(
        Messenger::Request.new(
          Messenger::Elements::Text.new(text: "Echo: #{messaging.callback.text}"),
          messaging.sender_id
        )
      )
    end
  end
end

Or with first_entry method:

if fb_params.first_entry.callback.message?
  Messenger::Client.send(
    Messenger::Request.new(
      Messenger::Elements::Text.new(text: "Echo: #{fb_params.first_entry.callback.text}"),
      fb_params.first_entry.sender_id
    )
  )
end

fb_params

Has control over entries. Especially callback attribute of messaging instance has following methods:

• message?
• delivery?
• postback?
• optin?
• attachments
• text

Example usage:

fb_params.first_entry.callback.message?
fb_params.first_entry.callback.postback?
fb_params.first_entry.callback.delivery?
fb_params.first_entry.callback.optin?
fb_params.first_entry.callback.attachments
fb_params.first_entry.callback.text

Development

After checking out the repo, run bin/setup to install dependencies. You can also run rake console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/netguru/messenger-ruby.

License

The gem is available as open source under the terms of the MIT License.