This document discusses serverless architecture as an alternative to traditional 3-tier architecture. It shows how serverless applications use managed AWS services like Lambda, DynamoDB, S3 and API Gateway instead of application servers. Key services are coordinated by Lambda functions to provide authentication, file uploads, database access and APIs. The document provides code examples for building serverless applications using services like Cognito, IAM and Amplify.

1. Application
Server-less Web Apps
www.seed.run

2. SEED is a fully-managed
CI/CD for Serverless.
Frank Jay
💎
@fanjiewang @jayair
www.seed.run

3. serverless-stack.com
Serverless Stack is an open source guide for
building full-stack production ready
Serverless applications on AWS.
★ 1.2K 30K 👤 7K ✉

5. 🧐
3-Tier Architecture

6. 🖥
CLIENT APP SERVER DB SERVER

7. Provides an API
Handles requests
Handles file uploads
Authenticates users
Secures the application
Runs scheduled jobs & tasks
APP SERVER

8. The App Server
does everything…

9. Everything except
storing data 😮

10. 🖥
CLIENT APP SERVER
DB SERVER
S3 UPLOADS
SEARCH

11. App Server is the
“gatekeeper”

12. ⚡
Serverless Architecture

13. 🖥
SPA
COGNITO
DYNAMO
S3 UPLOADS
ELASTIC
🔑
IAM
🔐
LAMBDA

14. SERVERLESS
⚡
Client coordinates services
Fully-managed architecture
Glued together with Lambda
Use a separate auth provider
Secure all services with IAM
Services auto-scale to traffic

15. SERVERLESS
⚡
1. User authenticates client side
2. Make signed requests to a service
3. Service checks if user has access
4. Service responds over HTTPS

16. 🔥
Code

17. Project files
handler.js
serverless.yml
package.json

18. serverless.yml

19. service: posts
provider:
name: aws
runtime: nodejs8.10
iamRoleStatements:
- Effect: Allow
Action:
- dynamodb:PutItem
Resource: “arn:aws:dynamodb:us-east-1:*:*"
functions:
create:
handler: handler.create
- http:
path: posts/create
method: post
cors: true
authorizer: aws_iam

20. handler.js

21. module.create = function(evt, context, callback) {
// Federated user id
const userId = evt.requestContext.identity.cognitoIdentityId;
. . .
await dynamoDbLib.call("put", params);
callback(null, success(params.Item));
};

22. S3 Uploads

23. <CORSConfiguration>
<CORSRule>
<AllowedOrigin>*</AllowedOrigin>
<AllowedMethod>GET</AllowedMethod>
<AllowedMethod>PUT</AllowedMethod>
<AllowedMethod>POST</AllowedMethod>
<AllowedMethod>HEAD</AllowedMethod>
<AllowedMethod>DELETE</AllowedMethod>
<MaxAgeSeconds>3000</MaxAgeSeconds>
<AllowedHeader>*</AllowedHeader>
</CORSRule>
</CORSConfiguration>

24. COGNITO
🔑
1. Create a User Pool
2. Configure user attributes
3. Create an app client
4. Done!

25. 🔐
AWS IAM

26. {
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [ "s3:*" ],
"Resource": [
"arn:aws:s3:::S3_BUCKET/${cognito-identity.amazonaws.com:sub}/*"
]
},
{
"Effect": "Allow",
"Action": [ "execute-api:Invoke" ],
"Resource": [
"arn:aws:execute-api:us-east-1:*:API_GATEWAY_ID/*"
]
}
]
}

27. AWS Amplify
h"ps://aws-amplify.github.io/amplify-js/

28. Amplify.configure({
Auth: {
region: COGNITO_REGION,
userPoolId: COGNITO_USER_POOL,
identityPoolId: COGNITO_IDENTITY_POOL,
userPoolWebClientId: COGNITO_APP_CLIENT
},
Storage: {
region: S3_REGION,
bucket: S3_BUCKET
},
API: {
endpoints: [{
name: "posts",
endpoint: API_GATEWAY_URL,
region: API_GATEWAY_REGION
}]
}
});

29. Sign in a User

30. import { Auth } from “aws-amplify”;
. . .
// Sign up
await Auth.signUp({ username, password });
await Auth.confirmSignUp(username, confirmationCode);
. . .
// Login
await Auth.signIn(username, password);

31. Upload a File

32. import { Storage } from “aws-amplify";
. . .
await Storage.vault.put(
filename,
file,
{ contentType }
);

33. Call an API

34. import { API } from "aws-amplify";
. . .
await API.post("posts", "/posts", {
body: post
});

35. Static Hosting

36. HOSTING
1. Create a public S3 bucket
2. Link to a CloudFront distribution
3. Attach a domain on Route 53
4. Add SSL with Certificate Manager

37. $ npm run build
$ aws s3 sync build/ s3://S3_HOSTING_BUCKET

38. 🎉
Recap

39. PARTY
Massively scalable web app
Fully-managed architecture
Extremely low-cost to run
And no application servers!
🎉

40. 🙌
Closing

41. Learn to build Serverless apps
Serverless-Stack.com

42. Fully-managed Serverless CI/CD
SEED.run

43. Frank Jay
💎
@fanjiewang @jayair
Questions?