MessengerBot

Unofficial Facebook Messenger Platform chatbot client and webhook handler

MessengerBot covers majority of the functions to make calls to Facebook Messenger Platform endpoints.

MessengerBot library is designed for processing webhook events coming from Facebook with an event driven approach. It allows any number of subscribers to process same data without blocking.

Installation

The package can be installed by adding messenger_bot to your list of dependencies in mix.exs:

def deps do
  [{:messenger_bot, "~> 1.0"}]
end

Configuration

Facebook Messenger App and Page configurations

App and Page configurations can be done via config.exs and MessengerBot.Config module. Basic idea is to store apps and pages are type of MessengerBot.Model.{App, Page} types.

If you are using the app for a single page, config.exs seems to be right place but if you need to load app info from an external source, then use module functions to save your apps.

Note:App and Page keys must be atom() type like in the examples. For config.exs you can add apps and pages like below:

alias MessengerBot.Model.{App, Page}

config :messenger_bot,
  pages: %{
    "1881" => %{
      "1234" => %{
        id: "1234",
        name: "Demo Facebook Messenger Bot",
        access_token: "accesstokenforpage"
      }
    }
  },
  apps: %{
    "1881" => %{
      id: "1881",
      secret: "SECRET",
      setup_token: "Setup Token",
      access_token: "ATOKEN123"
    }
  }

Any time after loading `messenger_bot`, you can add more pages for an app.

pages = %{ "1234" => %{

id: "1234",
name: "Demo Facebook Messenger Bot",
token: "accesstokenforpage"

}, "1298" => %{

id: "1298",
name: "Demo Facebook Messenger Bot 1298",
token: "accesstokenforpagefor1298"

} }

Update configurations

MessengerBot.Config.save_pages(app_id, pages)

Any time after loading `messenger_bot`, you can save apps too.

apps = %{ "1881" => %{

id: "1881",
secret: "SECRET",
setup_token: "Setup Token",
access_token: "ATOKEN123"

} }

Update configurations

MessengerBot.Config.save_apps(apps)

### Facebook App setup configuration

Add webhook endpoints to your router:

The code below will add following routes

-> GET /some-path-for-messenger_bot/:app_id (200)

-> POST /some-path-for-messenger_bot/:app_id (200)

-> MATCH /some-path-for-messenger_bot/:any (404)

forward "/some-path-for-messenger_bot", to: MessengerBot.Web.Router

### Event Topics Configuration

Update your `config.exs` to add `messenger_bot` event topics for `event_bus`:

config :event_bus, topics: [:mb_webhook_received,

:mb_delivery_received,
:mb_read_received,
:mb_message_echo_received,
:mb_message_attachments_received,
:mb_message_quick_reply_received,
:mb_message_received,
:mb_optin_received,
:mb_postback_received,
:mb_referral_received,
:mb_game_play_received,
:mb_payment_received,
:mb_checkout_update_received,
:mb_pre_checkout_received,
:mb_account_linking_received,
:mb_policy_enforcement_received,
:mb_app_roles_received,
:mb_standby_received,
:mb_pass_thread_control_received,
:mb_take_thread_control_received,
:mb_request_thread_control_received,
:mb_na_received,
:mb_app_setup_received,
:mb_attachment_upload_succeeded,
:mb_create_message_creatives_succeeded,
:mb_broadcast_message_succeeded,
:mb_pass_thread_control_succeeded,
:mb_take_thread_control_succeeded,
:mb_request_thread_control_succeeded,
:mb_fetch_secondary_receivers_succeeded,
:mb_id_matching_succeeded,
:mb_create_messenger_code_succeeded,
:mb_fetch_messaging_feature_review_succeeded,
:mb_fetch_insights_succeeded,
:mb_set_messenger_profile_succeeded,
:mb_reset_messenger_profile_succeeded,
:mb_fetch_messenger_profile_succeeded,
:mb_send_message_succeeded,
:mb_unlink_account_succeeded,
:mb_fetch_user_profile_succeeded,
:mb_attachment_upload_failed,
:mb_create_message_creatives_failed,
:mb_broadcast_message_failed,
:mb_pass_thread_control_failed,
:mb_take_thread_control_failed,
:mb_request_thread_control_failed,
:mb_fetch_secondary_receivers_failed,
:mb_id_matching_failed,
:mb_create_messenger_code_failed,
:mb_fetch_messaging_feature_review_failed,
:mb_fetch_insights_failed,
:mb_set_messenger_profile_failed,
:mb_reset_messenger_profile_failed,
:mb_fetch_messenger_profile_failed,
:mb_send_message_failed,
:mb_unlink_account_failed,
:mb_fetch_user_profile_failed,
:mb_attachment_upload_erred,
:mb_create_message_creatives_erred,
:mb_broadcast_message_erred,
:mb_pass_thread_control_erred,
:mb_take_thread_control_erred,
:mb_request_thread_control_erred,
:mb_fetch_secondary_receivers_erred,
:mb_id_matching_erred,
:mb_create_messenger_code_erred,
:mb_fetch_messaging_feature_review_erred,
:mb_fetch_insights_erred,
:mb_set_messenger_profile_erred,
:mb_reset_messenger_profile_erred,
:mb_fetch_messenger_profile_erred,
:mb_send_message_erred,
:mb_unlink_account_erred,
:mb_fetch_user_profile_erred]

## Usage

### Webhook handling

MessengerBot library handles allows you to handle all webhooks with subscription to the events.

#### How to subscribe to event topics?

`messenger_bot` package uses [event_bus library](https://github.com/otobus/event_bus) to sent/process Messenger events. Please refer to `event_bus` docs to learn more. You can subscribe registered events. To subscribe and log all events you can use `EventBus.subscribe({MessengerBot.Processor.Log, [".*"]})`.

Sample listener implementation for MessengerBot events

defmodule MessengerBot.Processor.Log do @listener MODULE

def process({topic, event_id}) do

event = EventBus.fetch_event({topic, event_id})
Logger.info(fn -> inspect(event) end)
EventBus.mark_as_completed({@listener, topic, event_id})

end end

### Using Client to make HTTP request to Facebook endpoints

All MessengerBot client functions can be found on [https://hexdocs.pm/messenger_bot](https://hexdocs.pm/messenger_bot).

## Contributing

### Issues, Bugs, Documentation, Enhancements

Create an issue if there is a bug.

Fork the project.

Make your improvements and write your tests(make sure you covered all the cases).

Make a pull request.

## License

LGPLv3

Copyright (c) 2018 Mustafa Turan

MessengerBot is an Open Source project licensed under the terms of the LGPLv3 license.  Please see <http://www.gnu.org/licenses/lgpl-3.0.html>
for license text.

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.