Serverless architectures simplify operations and maintenance of production applications, abstracting from the underlining infrastructure and OS. But what about development? In this session you will see some of the key points that can empower a serverless developer: from event-driven design, to simplification (less is more, especially for a small team), extending the functionalities of the platform (per prefix stats for S3, geohash for DynamoDB, API authentication, and so on), integrating new products.

1. Serverless for Developers
Danilo Poccia, Technical Evangelist
@danilop

2. Danilo Poccia
W
ith AWS Lambda, you write your code and upload it to
the AWS cloud. AWS Lambda responds to the events
triggered by your application or your users, and auto-
matically manages the underlying computer resources for you.
Back-end tasks like analyzing a new document or processing
requests from a mobile app are easy to implement. Your ap-
plication is divided into small functions, leading naturally to a
reactive architecture and the adoption of microservices.
AWS Lambda in Action is an example-driven tutorial that
teaches you how to build applications that use an event-driven
approach on the back-end. Starting with an overview of AWS
Lambda, the book moves on to show you common examples
and patterns that you can use to call Lambda functions from
a web page or a mobile app. The second part of the book puts
these smaller examples together to build larger applications.
By the end, you’ll be ready to create applications that take
advantage of the high availability, security, performance, and
scalability of AWS.
What’s Inside
● Create a simple API
● Create an event-driven media sharing application
● Secure access to your application in the cloud
● Use functions from different clients like web pages
or mobile apps
● Connect your application with external services
Requires basic knowledge of JavaScript. Some examples are
also provided in Python. No AWS experience is assumed.
Danilo Poccia is a technical evangelist at Amazon Web Services
and a frequent speaker at public events and workshops.
To download their free eBook in PDF, ePub, and Kindle formats, owners
of this book should visit www.manning.com/books/aws-lambda-in-action
$49.99 / Can $57.99 [INCLUDING eBOOK]
AWSLambdaINACTION
SOFTWARE DEVELOPMENT/CLOUD
Danilo
Poccia
M A N N I N G
AWSLambdaINACTION
MANNING
“Clear and concise …
the code samples are as well
structured as the writing.
”—From the Foreword by
James Governor, RedMonk
“A superb guide to an
important aspect of AWS.
”—Ben Leibert, VillageReach
“Step-by-step examples
and clear prose make this
the go-to book for
AWS Lambda!.
”—Dan Kacenjar, Wolters Kluwer
“Like Lambda itself, this
book is easy to follow, concise,
and very functional.
”—Christopher Haupt, New Relic
M A N N I N G
SEE INSERT
Danilo Poccia
FOREWORD BY James Governor
Event-driven serverless applications

3. Function

4. <demo>
greetingsOnDemand
</demo>

5. Function

6. Function

7. Client Application
Function
invoke

8. Client Application
Function
Database
Files
invoke
read/write

9. Client Application
Function2
Database
Files
Function1
Function3
invoke
event trigger
event trigger
read/write

10. Business LogicClient Application
Function2
Database
Files
Function1
Function3
invoke
event trigger
event trigger
read/write

11. Data PersistenceBusiness LogicClient Application
Function2
Database
Files
Function1
Function3
invoke
event trigger
event trigger
read/write

12. Data PersistenceBusiness Logic
Client
Application
FunctionsFunctionsFunctions RepositoriesRepositoriesRepositoriesAPI read/write
event trigger

13. Data PersistenceBusiness Logic
Client
Application
FunctionsFunctionsFunctions RepositoriesRepositoriesRepositoriesAPI read/write
event trigger
read/write

14. Data PersistenceBusiness Logic
Client
Application
FunctionsFunctionsFunctions
API
Gateway
RepositoriesRepositoriesRepositoriesAPI read/write
event trigger
read/write

15. Request – Input Format
{
"resource": "Resource path",
"path": "Path parameter",
"httpMethod": "Incoming request's method name",
"headers": { Incoming request headers },
"queryStringParameters": { Query string parameters },
"pathParameters": { Path parameters },
"stageVariables": { Applicable stage variables },
"requestContext": { Request context, including authorizer-returned key-value pairs },
"body": "A JSON string of the request payload",
"isBase64Encoded": "A boolean flag to indicate if the applicable request payload is Base64-encode"
}
Response – Output Format
{
"statusCode": httpStatusCode,
"headers": { "headerName": "headerValue", ... },
"body": "...”
}
Lambda
Function
Amazon API
Gateway

16. <demo>
greetingsAPI
</demo>

17. How do I start?

18. No Servers
to Manage
Continuous
Scaling
Subsecond
Metering
AWS Lambda
1 Million requests
per month
400,000 GB-seconds
per month
Free Tier

19. https://github.com/awslabs/chalice
$ pip install chalice
$ chalice new-project helloworld && cd helloworld
$ cat app.py
from chalice import Chalice
app = Chalice(app_name="helloworld")
@app.route("/")
def index():
return {"hello": "world"}
$ chalice deploy
...
Your application is available at: https://endpoint/dev
$ curl https://endpoint/dev
{"hello": "world"}

20. <demo>
chalice
</demo>

21. https://serverless.com

22. https://github.com/awslabs/aws-serverless-auth-reference-app
Serverless reference app and backend API, showcasing authentication and
authorization patterns using Amazon Cognito, Amazon API Gateway, AWS
Lambda, and AWS IAM

23. <demo>
aws-serverless-auth-reference-app
</demo>

24. Building An Infinitely Scalable Online Recording Campaign
For David Guetta & UEFA

25. Do I need to rebuild everything?

26. https://github.com/awslabs/aws-serverless-express
This library enables you to utilize AWS Lambda and Amazon API Gateway to
respond to web and API requests using your existing Node.js application
framework

27. https://github.com/awslabs/aws-serverless-java-container
A Java wrapper to run Jersey, Spark, and other apps inside AWS Lambda

28. <demo>
aws-serverless-express
</demo>

29. How to go beyond the timeout?

30. function processList(itemList, context) {
var item = itemList.shift();
processItem(item, () => {
if (itemList.length === 0) {
console.log('Finished');
} else if (context.getRemainingTimeInMillis() > TIME_THRESHOLD) {
// Process remaning items
processList(itemList, context);
} else {
console.log('Not finished');
// Time is running out,
// invoke self asynchrounously to process remaning items
invokeSelf(itemList, context);
}
});
}
For example…

31. What about larger apps?

32. https://github.com/awslabs/serverless-application-model

33. </>
Serverless Continuous Integration and Deployment
GitHub
Amazon S3
AWS CodeCommit
AWS CodeBuild AWS CodeBuild
third-party tools
AWS CloudFormation
Commit Build Test
Deploy
to Prod
AWS CodePipeline + SAM

34. <demo>
serverless-application-model
</demo>

35. AWS Step Functions
Sequential
Steps
Branching Steps
(Choice of Path)
Parallel
Steps

36. https://states-language.net/spec.html

37. <demo>
AWS Step Functions
</demo>

38. Event-Driven Architecture

39. Name
Email
Create New User
Submit
Check the “Name” syntax is right
(only letters and spaces)
Check the “Email” syntax is right
(something@some.domain)
Create the new user using
provided Name and Email
User Interface Actions

40. Name
Email
Create New User
Submit
Check the “Name” syntax is right
(only letters and spaces)
Check the “Email” syntax is right
(something@some.domain)
Create the new user using
provided Name and Email
User Interface ActionsObservers
Target Action

41. Generate thumbnails
Keep another database in sync
Process streaming data
Services FunctionsPlatform
Target Action
Kinesis
Stream
DynamoDB
Table
S3
Bucket

42. area = length x width
What do you see here?

43. area = length x width
Procedural Programming
“This is a function!”

44. area = length x width
Procedural Programming
“This is a function!”
Reactive Programming
“This is data binding!”

45. To Leverage Even-Driven Architectures,
You May Need to Take a Different Point of View

46. A B
Event-Driven Design
For Services
”Service A triggers B"
or better
”Service B is caused by A"

47. A B
C
D
E
F
?
?
What is causing
services E and F?

48. A B
C
D
E
F
New services (E, F)
are triggered caused by C

49. A B
C
D
E
F
It can be cyclic
Think of
acknowledgements

50. Each service
has local visibility
A B
C
D
E
F

51. What I need to know
(input events)
1
A B
C
D
E
F

52. What I need to do
(internal logic)
2
A B
C
D
E
F

53. Who I need to notify
(output events)
3
A B
C
D
E
F

54. Who I need to notify
(output events)
What I need to know
(input events)
What I need to do
(internal logic)
1
2
3
B

55. A B
C
D
E
F
Distributed Data Flow
Vs
Centralised Workflow

56. A B
C
D
E
F
Choreography
Vs
Orchestration

57. Microservices
Distributed Systems

58. Monolith
Service
Service
μ
μ
μ
space (distribution, mobility)
time(concurrency,latency)
μ
μ
μ
μ
“Distributed
in Time and Space”
[Jonas Bonér]

59. “…a diagram of
two microservices
and their shared database”
Data should drive
the boundaries

60. A
C
I
D
tomic
onsistent
solated
urable

61. A
C
I
D
tomic
onsistent
solated
urable
A
C
I
D
ssociative
ommutative
dempotent
istributed
ACID 2.0

62. Prototype
Production

63. Responsive
ResilientElastic
Message Driven
The Reactive Manifesto

64. Asynchronous
communication
is not enforced
by serverless architectures
Responsive
ResilientElastic
Message Driven
The Reactive Manifesto

65. Lambda Everywhere

66. AWS Greengrass

67. AWS Snowball Edge

68. AWS Snowball Edge

69. AWS Snowmobile

70. Lambda@Edge

71. Build Apps With Services,
Not Servers

72. https://aws.amazon.com/lambda
https://github.com/awslabs/aws-serverless-auth-reference-app
https://github.com/awslabs/aws-serverless-express
https://github.com/awslabs/chalice
https://github.com/awslabs/aws-serverless-java-container
https://serverless.com
https://github.com/awslabs/serverless-application-model
https://states-language.net/spec.html
https://github.com/danilop/AWS_Lambda_in_Action
For Your Reference

73. Danilo Poccia
@danilop
Your feedback
is important to us!