Core API

Bot Class

The Bot class provides the main interface for interacting with the Facebook Messenger API. It simplifies the process of setting up a webhook server, handling incoming messages, and sending responses.

Constructor

constructor(options: Options)

Parameters:

• options: Configuration options for the Bot instance. The Options interface includes:
• accessToken (string): The Facebook App access token.
• verifyToken (string): The verification token for webhook setup.
• port (number, optional): The port number for the server (default: 8080).
• endpoint (string, optional): The webhook endpoint (default: '/webhook').
• version (string, optional): The Facebook Graph API version (default: 'v19.0').

start

public start(): void

Starts the bot server and sets up the webhook endpoints. This method handles both the verification of the webhook setup and the reception of incoming messages.

• Webhook Verification: Responds to Facebook's GET request for webhook verification using the verifyToken.
• Message Handling: Receives POST requests and emits events based on the incoming messages.

sendRequest

public async sendRequest<T>(
    method: 'GET' | 'POST',
    endpoint: string,
    requestBody?: Record<string, unknown>,
): Promise<T>

Sends an HTTP request to the Facebook Graph API.

Parameters:

• method: The HTTP method to use ('GET' or 'POST').
• endpoint: The API endpoint to request.
• requestBody (optional): The body of the request for 'POST' requests.

sendMessage

public async sendMessage(recipientId: string, message: object): Promise<void>

Sends a message to a recipient.

Parameters:

• recipientId: The ID of the recipient.
• message: The message object to send.

sendTextMessage

public async sendTextMessage(recipientId: string, message: string): Promise<void>

Sends a text message to a recipient.

Parameters:

• recipientId: The ID of the recipient.

• message: The text message to send.

• Throws: Will throw an error if the message exceeds 2000 characters.

sendAttachment

public async sendAttachment(
    recipientId: string,
    type: 'audio' | 'file' | 'image' | 'video' | 'template',
    url: string,
    isReusable?: boolean
): Promise<void>

Sends an attachment (audio, file, image, video, or template) to a recipient.

Parameters:

• recipientId: The ID of the recipient.
• type: The type of the attachment.
• url: The URL of the attachment.
• isReusable (optional): Whether the attachment is reusable (default: true).

setTyping

public async setTyping(recipientId: string, isTyping: boolean): Promise<void>

Sets the typing status of the recipient.

Parameters:

• recipientId: The ID of the recipient.
• isTyping: Whether the recipient is typing (true or false).

Additional Information

• Error Handling: The sendRequest method throws an error if the response is not successful, providing detailed error information.
• Event Emission: The Bot class extends EventEmitter and can emit events based on incoming messages.

This class provides a powerful and flexible way to interact with the Facebook Messenger Platform, handling both message reception and response efficiently.