baseimage-tutorial-framework/lib/tfw/components/frontend/message_sender.py

class MessageSender:
    """
    Provides mechanisms to send messages to our frontend messaging component.
    """
    def __init__(self, uplink):
        self.uplink = uplink
        self.key = 'message'
        self.queue_key = 'queueMessages'

    def send(self, originator, message):
        """
        Sends a message.
        :param originator: name of sender to be displayed on the frontend
        :param message: message to send
        """
        message = {
            'key': self.key,
            'data': {
                'originator': originator,
                'message': message
            }
        }
        self.uplink.send_message(message)

    def queue_messages(self, originator, messages):
        """
        Queues a list of messages to be displayed in a chatbot-like manner.
        :param originator: name of sender to be displayed on the frontend
        :param messages: list of messages to queue
        """
        message = {
            'key': self.queue_key,
            'data': {
                'messages': [
                    {'message': message, 'originator': originator}
                    for message in messages
                ]
            }
        }
        self.uplink.send_message(message)

    @staticmethod
    def generate_messages_from_queue(queue_message):
        for message in queue_message['data']['messages']:
            yield {
                'key': 'message',
                'data': message
            }