Amazon Lex

Hands-On

Demo

In this demo, we will:

Create a Lex bot for pizza ordering
Define intents and configure slot types
Add sample utterances and train the bot
Create a Lambda function for order processing
Configure bot fulfillment with Lambda
Test the conversational flow
Clean up resources

Agenda

Create bot

Configure bot settings

PizzaOrderBot

Bot configuration

A bot to take pizza orders

IAM permissions

Bot error logging

Children's Online Privacy Protection Act (COPPA)

Idle session timeout

Advanced settings - optional

Add language to bot

Slots

Add slot type

Add blank slot type

PizzaSize

Add blank slot type

Slot type details

PizzaSize

Available pizza sizes

Slot value resolution

small

medium

large

Slot type values

Add a 2nd blank slot type

PizzaType

Add blank slot type

Available pizza types

Slot type details

Slot type values

margherita

pepperoni

vegetarian

hawaiian

Add intent

Add empty intent

OrderPizza

Intent to order a pizza

Intent details

Contexts - optional

I want to order a pizza
I'd like a {PizzaSize} {PizzaType} pizza
Can I get a {PizzaType} pizza
I want a {PizzaSize} pizza
Order a {PizzaType} pizza please
I'd like to order a {PizzaSize} {PizzaType}
Get me a pizza
Pizza order
Can I order a {PizzaType}
I need a {PizzaSize} {PizzaType} pizza

Sample utterances

Add slot

What type of pizza would you like?

PizzaType

Add slot

PizzaSize

What size would you like?

Add slot

Quantity

How many pizzas would you like?

Slots

Confirmation

You want to order {Quantity} {PizzaSize} {PizzaType} pizza(s). Is that correct?

Okay, let's start over. What would you like to order?

Fulfillment & Closing response

Save intent

Create Lambda function

PizzaOrderProcessor

Permissions

Additional configurations

import json
import random
import string

def lambda_handler(event, context):
    # Extract intent name
    intent_name = event['sessionState']['intent']['name']
    
    # Extract slot values
    slots = event['sessionState']['intent']['slots']
    
    if intent_name == 'OrderPizza':
        pizza_type = slots['PizzaType']['value']['interpretedValue']
        pizza_size = slots['PizzaSize']['value']['interpretedValue']
        quantity = slots['Quantity']['value']['interpretedValue']
        
        # Generate order number
        order_number = ''.join(random.choices(string.ascii_uppercase + string.digits, k=8))
        
        # Calculate price (simplified pricing)
        size_prices = {'small': 10, 'medium': 15, 'large': 20}
        base_price = size_prices.get(pizza_size, 15)
        total_price = base_price * int(quantity)
        
        # Prepare fulfillment message
        fulfillment_message = (
            f"Great! Your order has been placed. "
            f"Order #{order_number}: {quantity} {pizza_size} {pizza_type} pizza(s). "
            f"Total: ${total_price}. "
            f"Your order will be ready in 30-40 minutes."
        )
        
        response = {
            "sessionState": {
                "dialogAction": {
                    "type": "Close"
                },
                "intent": {
                    "name": intent_name,
                    "state": "Fulfilled"
                }
            },
            "messages": [
                {
                    "contentType": "PlainText",
                    "content": fulfillment_message
                }
            ]
        }
    else:
        response = {
            "sessionState": {
                "dialogAction": {
                    "type": "Close"
                },
                "intent": {
                    "name": intent_name,
                    "state": "Failed"
                }
            },
            "messages": [
                {
                    "contentType": "PlainText",
                    "content": "Sorry, I couldn't process your request."
                }
            ]
        }
    
    return response