Andrew Carreiro presents at the Fall 2015 Toronto Node.js meetup.

1. Building your own Slack bot on
the modern AWS stack
Andrew Carreiro
Platform Architect, Klick Health

2. Demo

3. Basic Structure

4. Slack
Chat app that lets us POST data by typing /8ball

5. Amazon API Gateway
Receives the request from Slack, and routes the
request to Lambda

6. Amazon Lambda
Evaluates the chat command, and returns a response.

7. Amazon DynamoDB
NoSQL backend for the app

8. API Gateway
Lambda
DynamoDB
/8ball Should I try AWS?
POST
Invokes
Possible
answers are
saved & read
Responds
Responds
“Absolutely!” 8

9. DynamoDB

10. Why DynamoDB?
- Need for this app: persistent data store across requests
- A JSON file on S3 also a possibility given scale
- Something like Redis (Amazon Elasticache) could also work, but price
prohibitive
- DynamoDB pricing structure is confusing, but you get 25GB storage and
~200M requests per month in the Free Tier

11. API Gateway
Lambda
DynamoDB
/8ball Should I try AWS?
POST
Invokes
Possible
answers are
saved & read
Responds
Responds
“Absolutely!” 8

12. Writing the Lambda
Function

13. What is Amazon Lambda?
- Old method: I need a server to execute my code
- Server sits idle sometimes, other times is completely overwhelmed
- Use AWS computing power, and be billed by the 100ms
- Theoretically infinitely scalable, if you have the money
- Can run Node, Java, or Python

14. Coding for Lambda
- Amazon Lambda uses Node.js: v0.10.36
- Deployment in it’s most basic state involves a manual zip upload
- lightweight is best-- adding Babel.js was a pain for uploads
- Expect your tests to work locally

15. Coding for Lambda
Create a user and credentials for what you need:
https://console.aws.amazon.com/iam/home?region=us-east-1#users

16. ~/.aws/config
[default]
output = json
region = us-east-1
Coding for Lambda: Config and Credentials
~/.aws/credentials
[default]
aws_access_key_id =
LINDNWVQQKAKP7BIA5TX
aws_secret_access_key =
L4Q8mgs4o4dO4qe3RBbXPSZPfhOQF
nj1U2dlDn30

17. Lambda Example
Code

18. Deploying Lambda

19. Approaches
https://github.com/mentum/lambdaws
https://github.com/jaws-framework/JAWS

20. Manual Lambda
setup

21. API Gateway
Lambda
DynamoDB
/8ball Should I try AWS?
POST
Invokes
Possible
answers are
saved & read
Responds
Responds
“Absolutely!” 8

22. Setting up API
Gateway

23. API Gateway
Lambda
DynamoDB
/8ball Should I try AWS?
POST
Invokes
Possible
answers are
saved & read
Responds
Responds
“Absolutely!” 8

24. Adding a Slash
Command on Slack

25. GitHub Repo
github.com/andrewcarreiro/slack-8ball

26. RyanRay URL Encoding gist
https://gist.github.com/ryanray/668022ad2432e38493df

27. Klick Health is hiring!

28. Thanks