Slides from intro workshop at JavaZone 2019 on building applications using Serverless Framework and AWS Lambda.

1. Building applications with
Serverless Framework
and AWS Lambda
Fredrik Vraalsen
JavaZone 2019
© Thomas Ekströmhttp://github.com/fredriv/serverless-lambda-workshop

2. http://github.com/fredriv/serverless-lambda-workshop
Clone Git repo and follow setup instructions in README:
Install npm, pip, Serverless Framework, Docker, awscli-local
Pre-fetch Docker images:
docker pull localstack/localstack:0.10.2
docker pull lambci/lambda:python3.7
2

3. Workshop agenda
Why serverless?
AWS Lambda
Serverless Framework
Configuration and
deployment
Backend API
3
Event processing
Orchestration
Performance
Packaging
Testing
http://github.com/fredriv/serverless-lambda-workshop

4. Who is Fredrik?
Oslo, Norway
Developer for 22+ years
Data Platform Architect at
Origo (City of Oslo)
Dad, cyclist, gamer,
sci-fi fan, photo geek
4

5. The Story of Tim
5
https://www.youtube.com/watch?v=xPciIWM3ztQ

6. 6
Analytics and insights
External data sources,
e.g. land registry,
weather, census data,
etc.
Sensors
Database extracts
Open
data
Share with
businesses
New services,
cross sector
Data catalog
Transform, clean
Simplify,
prepare,
publish
Professional
systems
Patient data,
school systems,
archives, etc
Government
registers
DATA
PLATFORM

7. Serverless / Lambda in our Data Platform
Microservices - REST APIs
Processing pipeline components
• Transformations
• Validation
Scheduled jobs
• Data integrations, backups, …
7http://github.com/fredriv/serverless-lambda-workshop

8. Why serverless?
No servers to manage
Quick deployment
Auto scaling
Pay-per-use
8http://github.com/fredriv/serverless-lambda-workshop

9. AWS Lambda
https://aws.amazon.com/lambda/
9http://github.com/fredriv/serverless-lambda-workshop

10. AWS Lambda
Function-as-a-Service (FaaS)
Serverless
Pay for compute time (+ memory)
10http://github.com/fredriv/serverless-lambda-workshop

11. 11
Simple Notification Service (SNS)
Simple Queue Service (SQS)
Simple Storage Service (S3)
Kinesis
API Gateway Step Functions
DynamoDB

12. Hello World
def hello(event, context):
name = event["queryStringParameters"]["name"]
return {
"statusCode": 200,
"body": f"Hello, {name}!",
"headers": {
"Content-Type": "text/plain"
}
}
12

13. Lambda demo
13

14. Manual configuration and deployment
14© Fredrik Vraalsen

15. Infrastructure as Code
15http://github.com/fredriv/serverless-lambda-workshop

16. Infrastructure as Code Configuration
16http://github.com/fredriv/serverless-lambda-workshop

17. 17
https://serverless.com/framework/

18. Serverless Framework
Configure and deploy serverless applications
Multi-cloud
18http://github.com/fredriv/serverless-lambda-workshop

19. Configuration and deployment
In git repo: 1_hello
19http://github.com/fredriv/serverless-lambda-workshop

20. Templates
sls create "--template aws-python3 "--name hello
20
https://serverless.com/framework/docs/providers/aws/cli-reference/create/

21. serverless.yml
service: hello
provider:
name: aws
region: eu-west-1
runtime: python3.7
functions:
hello:
handler: handler.hello
21

22. handler.py
def hello(event, context):
return "Hello, world!"
22

23. Deployment
23

24. Deployment
24

25. Deployment
25

26. Deployment
26

27. Invoking function
27

28. Undeploy
28

29. LocalStack
Run mock AWS services locally
Error injection
Run in Docker or locally
Integrations with test frameworks
29
https://localstack.cloud/

30. Exercise 1 - Hello!
Open directory 1_hello
Do exercises in README.md
30http://github.com/fredriv/serverless-lambda-workshop

31. Lambda use cases
Backend APIs
Web applications
Event processing
File processing
ETL
31http://github.com/fredriv/serverless-lambda-workshop

32. Lambda use cases
Backend APIs
Web applications
Event processing
File processing
ETL
32http://github.com/fredriv/serverless-lambda-workshop

33. Backend API
In git repo: 2_hello_http
https://serverless.com/framework/docs/providers/aws/events/apigateway/
33http://github.com/fredriv/serverless-lambda-workshop

34. Hello HTTP!
functions:
hello:
handler: handler.hello
events:
- http:
path: hello/{name}
method: get
34

35. Hello HTTP!
def hello(event, context):
name = event["pathParameters"]["name"]
35

36. Hello HTTP!
def hello(event, context):
name = event["pathParameters"]["name"]
response = { "message": f"Hello, {name}!" }
36

37. Hello HTTP!
import json
def hello(event, context):
name = event["pathParameters"]["name"]
response = { "message": f"Hello, {name}!" }
return {
"statusCode": 200,
"body": json.dumps(response)
}
37
https://docs.aws.amazon.com/apigateway/latest/developerguide/set-up-lambda-proxy-integrations.html#api-gateway-simple-proxy-for-lambda-input-format

38. Deploy
38

39. Invoking function
39

40. Invoking function
40

41. Invoking function
41https://httpie.org/

42. Exercise 2 - Hello HTTP!
Open directory 2_hello_http
Do exercises in README.md
42http://github.com/fredriv/serverless-lambda-workshop

43. Documentation
43

44. Documentation
Plugin: serverless-aws-documentation
Request content, parameters, responses, headers
Swagger / OpenAPI
In git repo: 3_hello_documentation
44http://github.com/fredriv/serverless-lambda-workshop

45. Documentation
functions:
hello:
handler: handler.hello
events:
- http:
path: hello/{name}
method: get
documentation:
description: "Generate a personalized greeting"
pathParams:
-
name: "name"
description: "Name of person to be greeted"
required: true
methodResponses:
-
statusCode: "200"
responseModels:
application/json: "HelloResponse"
45

46. Documentation
custom:
documentation:
models:
-
name: HelloResponse
description: "Greeting response"
contentType: "application/json"
schema: ${file(models/hello-response.yml)}
plugins:
- serverless-aws-documentation
46

47. Documentation
47

48. Triggering Lambda functions
API Gateway
Application load balancer
SNS topic
SQS queue
Kinesis
DynamoDB
S3
48
Step functions
Websocket
IoT
Alexa
CloudWatch
Cognito
Schedule
https://serverless.com/framework/docs/providers/aws/events/

49. Triggering Lambda functions
API Gateway
Application load balancer
SNS topic
SQS queue
Kinesis
DynamoDB
S3
49
Step functions
Websocket
IoT
Alexa
CloudWatch
Cognito
Schedule
https://serverless.com/framework/docs/providers/aws/events/

50. Event processing
In git repo: 4_event_processing
https://serverless.com/framework/docs/providers/aws/events/sns/
https://serverless.com/framework/docs/providers/aws/events/sqs/
https://serverless.com/framework/docs/providers/aws/events/streams/
50http://github.com/fredriv/serverless-lambda-workshop

51. serverless.yml
functions:
handle_event:
handler: handler.handle_event
events:
- sns: my-events
51

52. handler.py
def handle_event(event, context):
for record in event["Records"]:
msg = record["Sns"]["Message"]
print(f"Got event: {msg}")
52
https://docs.aws.amazon.com/lambda/latest/dg/with-sns.html

53. Publish event
53

54. Publish event
54

55. Exercise 4 - Event processing
Open directory 4_event_processing
Do exercises in README.md
55http://github.com/fredriv/serverless-lambda-workshop

56. Orchestration
56
© Fredrik Vraalsen

57. Orchestration
In git repo: 5_orchestration
https://serverless.com/plugins/serverless-step-functions/
57http://github.com/fredriv/serverless-lambda-workshop

58. serverless.yml
functions:
validateTemperature:
handler: handler.validate_temperature
enrichLocation:
handler: handler.enrich_location
stepFunctions:
stateMachines:
ProcessTemperatures:
name: ProcessTemperatures
events:
- http:
path: temperatures
method: post
58

59. serverless.yml
definition:
StartAt: ValidateTemperature
States:
ValidateTemperature:
Type: Task
Resource:
Fn"::GetAtt: [ValidateTemperatureLambdaFunction, Arn]
Next: EnrichLocation
EnrichLocation:
Type: Task
Resource:
Fn"::GetAtt: [EnrichLocationLambdaFunction, Arn]
End: True
59

60. handler.py
def validate_temperature(event, context):
temperature = int(event["temperature"])
if temperature < -20:
raise ValueError("Too cold!")
if temperature > 30:
raise ValueError("Too warm!")
return event
def enrich_location(event, context):
event["location"] = "Berlin"
return event
60

61. Running
61

62. 62

63. 63

64. 64

65. Exercise 5 - Orchestration
Open directory 5_orchestration
Do exercises in README.md
65http://github.com/fredriv/serverless-lambda-workshop

66. Performance
66© Fredrik Vraalsen

67. Cold start
67© Fredrik Vraalsen

68. Lambda lifecycle
68
https://blog.travelex.io/from-containers-to-aws-lambda-23f712f9e925

69. Lambda lifecycle
1 container = 1 execution
Spin up more on demand
Reuse: Freeze & Thaw
VPCs require ENIs ==> Slow cold start
69

70. Packaging
Deploy zip file
Bundle dependencies
Layers
Linux!
70
https://serverless.com/plugins/serverless-python-requirements/

71. Testing
separate business logic ==> unit tests, mocking
Python: moto library
sls invoke local -f function-name
kinesalite, dynalite, local dynamodb (docker)
LocalStack
71
https://serverless.com/framework/docs/providers/aws/guide/testing/

72. Putting it all together
72http://github.com/fredriv/serverless-lambda-workshop

73. Exercise 6 - All Together Now
Open directory 6_all_together
Do exercises in README.md
73http://github.com/fredriv/serverless-lambda-workshop

74. Wrap up
AWS Lambda
• FaaS, simple, pay-as-you-go, scalable
Serverless Framework
• Configuration, deployment, testing, plugins
• Easy = simpler, Hard = ?
• Continuously developed
74

75. More things
Infrastructure
Access control (IAM)
API Gateway integrations
• Lambda Proxy vs Lambda integration
Validation
Versioning
75

76. Questions? Feedback?
fredrik@vraalsen.no
@fredriv
76

77. Thanks for listening!
fredrik@vraalsen.no
@fredriv
77