The aws-serverless-express library enables you to build web services with Node.js and Express and run them as AWS Lambda functions delivered through the Amazon API Gateway. This talk will step through how to use this library to develop a simple API backed by DyamoDB, and how to deploy it to AWS via CloudFormation.

1. "Serverless"
Express
@AnnaGerber

2. Before
you
start
You’ll
need:
• An
AWS
account
• An
IAM
user
with
permissions
for
AWS
Lambda,
API
Gateway,
CloudFormation,
DynamoDB,
S3
and
CloudWatch
• Recent
version
AWS-­‐CLI
installed
https://aws.amazon.com/cli/

3. aws-­‐serverless-­‐express
Library
for
using
AWS
Lambda
and
Amazon
API
Gateway
with
Express
git clone
https://github.com/awslabs/aws-­‐serverless-­‐express
See
example directory
for
sample
app

4. AWS
Lambda

5. API
Gateway

6. Cloud
Formation

7. Example
app

8. AWS
SAM
• Serverless Application
Model
• JSON
or
YAML
• Defines
API
Gateway
APIs,
Lambda
functions,
DynamoDB tables

9. Configure
the
Sample
app

10. Setup
npm run
setup

11. Cloud
Formation
Stack

12. Stack
Outputs

13. Example
app

14. DynamoDB

15. Persisting
data
to
DynamoDB
To
persist
users
to
DynamoDB:
• Add
DynamoDB permissions
to
the
role
• Create
DynamoDB table
for
storing
users
• Modify
the
CRUD
routes
in
our
Express
app
to
use
DynamoDB instead
of
in-­‐memory
array

16. Update
role
permission

17. Create
Table
Users

18. Modify
the
routes
• Add
the
AWS
SDK
for
DynamoDB support
• npm install
-­‐-­‐save
aws-­‐sdk
var AWS
=
require("aws-­‐sdk")
var docClient =
new
AWS.DynamoDB.DocumentClient()

19. Create
a
User

20. List
Users

21. List
a
specific
User

22. Develop
your
API
• Continue
to
develop
as
for
regular
express
app
• Logs
for
the
app
can
be
accessed
via
CloudWatch
• Edit
package.json to
ensure
additional
resources
are
packaged
• To
re-­‐package
and
re-­‐deploy
the
app:
• npm run package-­‐deploy
• To
tear
down:
• npm run delete-­‐stack