Learn how to develop voice-based serverless back ends for Alexa Voice Service (AVS) and Alexa devices using the Alexa Skills Kit (ASK), which allows you to add new voice-based interactions to Alexa. We’ll code a new skill, implemented by a serverless backend leveraging AWS services such as Amazon Cognito, AWS Lambda, and Amazon DynamoDB. Often, your skill needs to authenticate your users and link them back to your backend systems and to persist state between user invocations. User authentication is performed by leveraging OAuth compatible identity systems. Running such a system on your back end requires undifferentiated heavy lifting or boilerplate code. We’ll leverage Login with Amazon as the identity provider instead, allowing you to focus on your application implementation and not on the low-level user management parts. At the end of this session, you’ll be able to develop your own Alexa skills and use Amazon and AWS services to minimize the required backend infrastructure. This session shows you how to deploy your Alexa skill code on a serverless infrastructure, leverage AWS Lambda, use Amazon Cognito and Login with Amazon to authenticate users, and leverage AWS DynamoDB as a fully managed NoSQL data store.

1. © 2016, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Sébastien Stormacq, Solution Architect, Alexa
ALX302
12/1/16
Build a Serverless Back End for Your Alexa-Based
Voice Interactions

2. What to Expect from the Session
• Learn about serverless back end
• Learn about persistence for Alexa Skills
• Learn about tight AWS security to the user invoking your
skill
What to expect from the session

3. What to Expect from the Session
• Login With Amazon
• AWS Lambda
• Amazon Cognito
• AWS Identity and Access Management
• Amazon DynamoDB
What to expect from the session

4. If you missed the Alexa Skill Kit…

6. Areas of improvement
• Infrastructure management
• Identity management
• Persistence
• Fine-grained permissions

7. Solution architecture

8. Your Skill Token
NoSQL database
Exchange LWA token for
AWS access key and secret key
Authenticate user
Receives OAuth token
Invoke
w/OAuth token
Identity provider
Use access key and secret key
to read/write items

9. Improvements to infrastructure
management

10. Infrastructure management
Your skill code

11. Infrastructure management
Amazon EC2

12. Infrastructure management

13. Infrastructure management

14. Infrastructure management
AWS Lambda
Amazon DynamoDB
Amazon Cognito

15. Improvements to managed service:
Lambda and DynamoDB

17. Managed service benefits
• Lower operational burden
• Lower cost
• Internet scalability
• Designed for very high availability

18. Improvements to identity management

19. Identify user across accounts/skills
Unique for { Amazon Account, Enabled Skill }

20. Identify user across accounts/skills
How to recognize users with multiple Amazon accounts?
How to recognize users after they re-enable the skill?

21. Improvements to account linking

26. Linking Alexa Skills with Login with Amazon

27. Account linking benefits
Stable account across:
• Multiple Amazon accounts
• Multiple skills
• Skills re-enablement

33. Amazon Cognito benefits
• Stable identity ID
• Distributes AWS credentials
• Limited in time
• Limited in scope

34. Improvements that enable persistence

35. User profile persistence
Let Alexa remember user preferences

36. User profile persistence
Let Alexa remember history

37. User profile persistence
Let Alexa remember context

38. Improvements to persistence (without adding
infrastructure)

40. Built into our ASK SDK for Node.js
http://sebs.to/asksdknodejs

42. Improvement for fine-grained
control: DynamoDB

46. DynamoDB benefits
• Entirely managed
• Internet scalability
• Cost effective

47. Improvement for fine-grained control:
DynamoDB access

48. Limit Lambda permissions per user
Is there a better way?

49. Improvement for fine-grained control:
Limit access to DynamoDB

51. What ?

52. Where ?

53. Who ?

54. AWS IAM roles benefits
• Distinct access policies for Lambda vs. authenticated
users
• Access to user’s DynamoDB items only

55. Benefits summary

56. Benefits
• No server-side infrastructure to manage
• Stable Amazon Cognito identity (across devices and
platforms)
• Lambda permissions limited per users
• Internet-style scalability
• Cost effective

57. Thank you!
@sebsto

58. Remember to complete
your evaluations!

59. Thursday
11:30am ALX202: How Amazon Is Enabling the Future of Automotive Venetian, Level 3, Lido
3003
1pm ALX303: Building a Smarter Home with Alexa Venetian, Level 3,
Murano 3203
3:30 ALX307: Voice-enabling Your Home and Devices with Amazon Alexa and AWS
IoT
Venetian, Level 2,
Opaline Theatre
5pm ALX302: Build a Serverless Back End for Your Alexa-Based Voice Interactions Venetian, Level 2,
Opaline Theatre
9:30am ALX304: Tips and Tricks on Bringing Alexa to Your Products Venetian, Level 1, Marco
Polo 806
11am ALX305: From VUI to QA: Building a Voice-Based Adventure Game for Alexa Venetian, Level 1, Marco
Polo 806
Friday 11am ALX203: Workshop: Creating Voice Experiences with Alexa Skills: From Idea to
Testing in Two Hours
Mirage, Jamaica B
1pm ALX306: State of the Union: Amazon Alexa and Recent Advances in
Conversational AI
Venetian, Level 2, Sands
Showroom
11:30am
and 2:30pm
ALX204: Workshop: Build an Alexa-Enabled Product with Raspberry Pi Mirage, Antigua B
5pm ALX301: Alexa in the Enterprise: How JPL Leverages Alexa to Further Space
Exploration with Internet of Things
Venetian, Level 2,
Venetian B
Wednesday